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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
2f0aea93 | 29 | #include <linux/suspend.h> |
90de2a4a | 30 | #include <linux/syscore_ops.h> |
5ff0a268 | 31 | #include <linux/tick.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
b4f0676f | 34 | static LIST_HEAD(cpufreq_policy_list); |
f963735a VK |
35 | |
36 | static inline bool policy_is_inactive(struct cpufreq_policy *policy) | |
37 | { | |
38 | return cpumask_empty(policy->cpus); | |
39 | } | |
40 | ||
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); |
0a300767 | 79 | static int cpufreq_start_governor(struct cpufreq_policy *policy); |
1da177e4 LT |
80 | |
81 | /** | |
32ee8c3e DJ |
82 | * Two notifier lists: the "policy" list is involved in the |
83 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
84 | * "transition" list for kernel code that needs to handle |
85 | * changes to devices when the CPU clock speed changes. | |
86 | * The mutex locks both lists. | |
87 | */ | |
e041c683 | 88 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 89 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 90 | |
74212ca4 | 91 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
92 | static int __init init_cpufreq_transition_notifier_list(void) |
93 | { | |
94 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 95 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
96 | return 0; |
97 | } | |
b3438f82 | 98 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 99 | |
a7b422cd | 100 | static int off __read_mostly; |
da584455 | 101 | static int cpufreq_disabled(void) |
a7b422cd KRW |
102 | { |
103 | return off; | |
104 | } | |
105 | void disable_cpufreq(void) | |
106 | { | |
107 | off = 1; | |
108 | } | |
29464f28 | 109 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 110 | |
4d5dcc42 VK |
111 | bool have_governor_per_policy(void) |
112 | { | |
0b981e70 | 113 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 114 | } |
3f869d6d | 115 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 116 | |
944e9a03 VK |
117 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
118 | { | |
119 | if (have_governor_per_policy()) | |
120 | return &policy->kobj; | |
121 | else | |
122 | return cpufreq_global_kobject; | |
123 | } | |
124 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
125 | ||
5a31d594 VK |
126 | struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu) |
127 | { | |
128 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
129 | ||
130 | return policy && !policy_is_inactive(policy) ? | |
131 | policy->freq_table : NULL; | |
132 | } | |
133 | EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table); | |
134 | ||
72a4ce34 VK |
135 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
136 | { | |
137 | u64 idle_time; | |
138 | u64 cur_wall_time; | |
139 | u64 busy_time; | |
140 | ||
141 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
142 | ||
143 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
144 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
145 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
146 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
147 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
148 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
149 | ||
150 | idle_time = cur_wall_time - busy_time; | |
151 | if (wall) | |
152 | *wall = cputime_to_usecs(cur_wall_time); | |
153 | ||
154 | return cputime_to_usecs(idle_time); | |
155 | } | |
156 | ||
157 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
158 | { | |
159 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
160 | ||
161 | if (idle_time == -1ULL) | |
162 | return get_cpu_idle_time_jiffy(cpu, wall); | |
163 | else if (!io_busy) | |
164 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
165 | ||
166 | return idle_time; | |
167 | } | |
168 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
169 | ||
70e9e778 VK |
170 | /* |
171 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
172 | * drivers of SMP systems. It will do following: | |
173 | * - validate & show freq table passed | |
174 | * - set policies transition latency | |
175 | * - policy->cpus with all possible CPUs | |
176 | */ | |
177 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
178 | struct cpufreq_frequency_table *table, | |
179 | unsigned int transition_latency) | |
180 | { | |
181 | int ret; | |
182 | ||
183 | ret = cpufreq_table_validate_and_show(policy, table); | |
184 | if (ret) { | |
185 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
186 | return ret; | |
187 | } | |
188 | ||
189 | policy->cpuinfo.transition_latency = transition_latency; | |
190 | ||
191 | /* | |
58405af6 | 192 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
193 | * share the clock and voltage and clock. |
194 | */ | |
195 | cpumask_setall(policy->cpus); | |
196 | ||
197 | return 0; | |
198 | } | |
199 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
200 | ||
1f0bd44e | 201 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
202 | { |
203 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
204 | ||
988bed09 VK |
205 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
206 | } | |
1f0bd44e | 207 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
208 | |
209 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
210 | { | |
211 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
212 | ||
652ed95d | 213 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
214 | pr_err("%s: No %s associated to cpu: %d\n", |
215 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
216 | return 0; |
217 | } | |
218 | ||
219 | return clk_get_rate(policy->clk) / 1000; | |
220 | } | |
221 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
222 | ||
50e9c852 VK |
223 | /** |
224 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
225 | * | |
226 | * @cpu: cpu to find policy for. | |
227 | * | |
228 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
229 | * It also increments the kobject reference count to mark it busy and so would | |
230 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
231 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
232 | * freed as that depends on the kobj count. | |
233 | * | |
50e9c852 VK |
234 | * Return: A valid policy on success, otherwise NULL on failure. |
235 | */ | |
6eed9404 | 236 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 237 | { |
6eed9404 | 238 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
239 | unsigned long flags; |
240 | ||
1b947c90 | 241 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
242 | return NULL; |
243 | ||
1da177e4 | 244 | /* get the cpufreq driver */ |
1c3d85dd | 245 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 246 | |
6eed9404 VK |
247 | if (cpufreq_driver) { |
248 | /* get the CPU */ | |
988bed09 | 249 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
250 | if (policy) |
251 | kobject_get(&policy->kobj); | |
252 | } | |
1da177e4 | 253 | |
6eed9404 | 254 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 255 | |
3a3e9e06 | 256 | return policy; |
a9144436 | 257 | } |
1da177e4 LT |
258 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
259 | ||
50e9c852 VK |
260 | /** |
261 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
262 | * | |
263 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
264 | * | |
265 | * This decrements the kobject reference count incremented earlier by calling | |
266 | * cpufreq_cpu_get(). | |
50e9c852 | 267 | */ |
3a3e9e06 | 268 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 269 | { |
6eed9404 | 270 | kobject_put(&policy->kobj); |
1da177e4 LT |
271 | } |
272 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
273 | ||
1da177e4 LT |
274 | /********************************************************************* |
275 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
276 | *********************************************************************/ | |
277 | ||
278 | /** | |
279 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
280 | * | |
281 | * This function alters the system "loops_per_jiffy" for the clock | |
282 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 283 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
284 | * per-CPU loops_per_jiffy value wherever possible. |
285 | */ | |
858119e1 | 286 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 287 | { |
39c132ee VK |
288 | #ifndef CONFIG_SMP |
289 | static unsigned long l_p_j_ref; | |
290 | static unsigned int l_p_j_ref_freq; | |
291 | ||
1da177e4 LT |
292 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
293 | return; | |
294 | ||
295 | if (!l_p_j_ref_freq) { | |
296 | l_p_j_ref = loops_per_jiffy; | |
297 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
298 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
299 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 300 | } |
0b443ead | 301 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
302 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
303 | ci->new); | |
e837f9b5 JP |
304 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
305 | loops_per_jiffy, ci->new); | |
1da177e4 | 306 | } |
1da177e4 | 307 | #endif |
39c132ee | 308 | } |
1da177e4 | 309 | |
0956df9c | 310 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 311 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
312 | { |
313 | BUG_ON(irqs_disabled()); | |
314 | ||
d5aaffa9 DB |
315 | if (cpufreq_disabled()) |
316 | return; | |
317 | ||
1c3d85dd | 318 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 319 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 320 | state, freqs->new); |
1da177e4 | 321 | |
1da177e4 | 322 | switch (state) { |
e4472cb3 | 323 | |
1da177e4 | 324 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 325 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
326 | * which is not equal to what the cpufreq core thinks is |
327 | * "old frequency". | |
1da177e4 | 328 | */ |
1c3d85dd | 329 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
330 | if ((policy) && (policy->cpu == freqs->cpu) && |
331 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
332 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
333 | freqs->old, policy->cur); | |
e4472cb3 | 334 | freqs->old = policy->cur; |
1da177e4 LT |
335 | } |
336 | } | |
b4dfdbb3 | 337 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 338 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
339 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
340 | break; | |
e4472cb3 | 341 | |
1da177e4 LT |
342 | case CPUFREQ_POSTCHANGE: |
343 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
344 | pr_debug("FREQ: %lu - CPU: %lu\n", |
345 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 346 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 347 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 348 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
349 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
350 | policy->cur = freqs->new; | |
1da177e4 LT |
351 | break; |
352 | } | |
1da177e4 | 353 | } |
bb176f7d | 354 | |
b43a7ffb VK |
355 | /** |
356 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
357 | * on frequency transition. | |
358 | * | |
359 | * This function calls the transition notifiers and the "adjust_jiffies" | |
360 | * function. It is called twice on all CPU frequency changes that have | |
361 | * external effects. | |
362 | */ | |
236a9800 | 363 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
364 | struct cpufreq_freqs *freqs, unsigned int state) |
365 | { | |
366 | for_each_cpu(freqs->cpu, policy->cpus) | |
367 | __cpufreq_notify_transition(policy, freqs, state); | |
368 | } | |
1da177e4 | 369 | |
f7ba3b41 | 370 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 371 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
372 | struct cpufreq_freqs *freqs, int transition_failed) |
373 | { | |
374 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
375 | if (!transition_failed) | |
376 | return; | |
377 | ||
378 | swap(freqs->old, freqs->new); | |
379 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
380 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
381 | } | |
f7ba3b41 | 382 | |
12478cf0 SB |
383 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
384 | struct cpufreq_freqs *freqs) | |
385 | { | |
ca654dc3 SB |
386 | |
387 | /* | |
388 | * Catch double invocations of _begin() which lead to self-deadlock. | |
389 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
390 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
391 | * double invocations are very low. Moreover, there are scenarios | |
392 | * where these checks can emit false-positive warnings in these | |
393 | * drivers; so we avoid that by skipping them altogether. | |
394 | */ | |
395 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
396 | && current == policy->transition_task); | |
397 | ||
12478cf0 SB |
398 | wait: |
399 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
400 | ||
401 | spin_lock(&policy->transition_lock); | |
402 | ||
403 | if (unlikely(policy->transition_ongoing)) { | |
404 | spin_unlock(&policy->transition_lock); | |
405 | goto wait; | |
406 | } | |
407 | ||
408 | policy->transition_ongoing = true; | |
ca654dc3 | 409 | policy->transition_task = current; |
12478cf0 SB |
410 | |
411 | spin_unlock(&policy->transition_lock); | |
412 | ||
413 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
414 | } | |
415 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
416 | ||
417 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
418 | struct cpufreq_freqs *freqs, int transition_failed) | |
419 | { | |
420 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
421 | return; | |
422 | ||
423 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
424 | ||
425 | policy->transition_ongoing = false; | |
ca654dc3 | 426 | policy->transition_task = NULL; |
12478cf0 SB |
427 | |
428 | wake_up(&policy->transition_wait); | |
429 | } | |
430 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
431 | ||
1da177e4 | 432 | |
1da177e4 LT |
433 | /********************************************************************* |
434 | * SYSFS INTERFACE * | |
435 | *********************************************************************/ | |
8a5c74a1 | 436 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
437 | struct attribute *attr, char *buf) |
438 | { | |
439 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
440 | } | |
441 | ||
442 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
443 | const char *buf, size_t count) | |
444 | { | |
445 | int ret, enable; | |
446 | ||
447 | ret = sscanf(buf, "%d", &enable); | |
448 | if (ret != 1 || enable < 0 || enable > 1) | |
449 | return -EINVAL; | |
450 | ||
451 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
452 | pr_err("%s: Cannot %s BOOST!\n", |
453 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
454 | return -EINVAL; |
455 | } | |
456 | ||
e837f9b5 JP |
457 | pr_debug("%s: cpufreq BOOST %s\n", |
458 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
459 | |
460 | return count; | |
461 | } | |
462 | define_one_global_rw(boost); | |
1da177e4 | 463 | |
42f91fa1 | 464 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
465 | { |
466 | struct cpufreq_governor *t; | |
467 | ||
f7b27061 | 468 | for_each_governor(t) |
7c4f4539 | 469 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
470 | return t; |
471 | ||
472 | return NULL; | |
473 | } | |
474 | ||
1da177e4 LT |
475 | /** |
476 | * cpufreq_parse_governor - parse a governor string | |
477 | */ | |
905d77cd | 478 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
479 | struct cpufreq_governor **governor) |
480 | { | |
3bcb09a3 | 481 | int err = -EINVAL; |
1c3d85dd | 482 | |
1c3d85dd | 483 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 484 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 485 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 486 | err = 0; |
7c4f4539 | 487 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 488 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 489 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 490 | err = 0; |
1da177e4 | 491 | } |
2e1cc3a5 | 492 | } else { |
1da177e4 | 493 | struct cpufreq_governor *t; |
3bcb09a3 | 494 | |
3fc54d37 | 495 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 496 | |
42f91fa1 | 497 | t = find_governor(str_governor); |
3bcb09a3 | 498 | |
ea714970 | 499 | if (t == NULL) { |
1a8e1463 | 500 | int ret; |
ea714970 | 501 | |
1a8e1463 KC |
502 | mutex_unlock(&cpufreq_governor_mutex); |
503 | ret = request_module("cpufreq_%s", str_governor); | |
504 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 505 | |
1a8e1463 | 506 | if (ret == 0) |
42f91fa1 | 507 | t = find_governor(str_governor); |
ea714970 JF |
508 | } |
509 | ||
3bcb09a3 JF |
510 | if (t != NULL) { |
511 | *governor = t; | |
512 | err = 0; | |
1da177e4 | 513 | } |
3bcb09a3 | 514 | |
3fc54d37 | 515 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 516 | } |
3bcb09a3 | 517 | return err; |
1da177e4 | 518 | } |
1da177e4 | 519 | |
1da177e4 | 520 | /** |
e08f5f5b GS |
521 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
522 | * print out cpufreq information | |
1da177e4 LT |
523 | * |
524 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
525 | * "unsigned int". | |
526 | */ | |
527 | ||
32ee8c3e DJ |
528 | #define show_one(file_name, object) \ |
529 | static ssize_t show_##file_name \ | |
905d77cd | 530 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 531 | { \ |
29464f28 | 532 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
533 | } |
534 | ||
535 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
536 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 537 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
538 | show_one(scaling_min_freq, min); |
539 | show_one(scaling_max_freq, max); | |
c034b02e | 540 | |
09347b29 | 541 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
542 | { |
543 | ssize_t ret; | |
544 | ||
545 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
546 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
547 | else | |
548 | ret = sprintf(buf, "%u\n", policy->cur); | |
549 | return ret; | |
550 | } | |
1da177e4 | 551 | |
037ce839 | 552 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 553 | struct cpufreq_policy *new_policy); |
7970e08b | 554 | |
1da177e4 LT |
555 | /** |
556 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
557 | */ | |
558 | #define store_one(file_name, object) \ | |
559 | static ssize_t store_##file_name \ | |
905d77cd | 560 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 561 | { \ |
619c144c | 562 | int ret, temp; \ |
1da177e4 LT |
563 | struct cpufreq_policy new_policy; \ |
564 | \ | |
8fa5b631 | 565 | memcpy(&new_policy, policy, sizeof(*policy)); \ |
1da177e4 | 566 | \ |
29464f28 | 567 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
568 | if (ret != 1) \ |
569 | return -EINVAL; \ | |
570 | \ | |
619c144c | 571 | temp = new_policy.object; \ |
037ce839 | 572 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
573 | if (!ret) \ |
574 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
575 | \ |
576 | return ret ? ret : count; \ | |
577 | } | |
578 | ||
29464f28 DJ |
579 | store_one(scaling_min_freq, min); |
580 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
581 | |
582 | /** | |
583 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
584 | */ | |
905d77cd DJ |
585 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
586 | char *buf) | |
1da177e4 | 587 | { |
d92d50a4 | 588 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
589 | if (!cur_freq) |
590 | return sprintf(buf, "<unknown>"); | |
591 | return sprintf(buf, "%u\n", cur_freq); | |
592 | } | |
593 | ||
1da177e4 LT |
594 | /** |
595 | * show_scaling_governor - show the current policy for the specified CPU | |
596 | */ | |
905d77cd | 597 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 598 | { |
29464f28 | 599 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
600 | return sprintf(buf, "powersave\n"); |
601 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
602 | return sprintf(buf, "performance\n"); | |
603 | else if (policy->governor) | |
4b972f0b | 604 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 605 | policy->governor->name); |
1da177e4 LT |
606 | return -EINVAL; |
607 | } | |
608 | ||
1da177e4 LT |
609 | /** |
610 | * store_scaling_governor - store policy for the specified CPU | |
611 | */ | |
905d77cd DJ |
612 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
613 | const char *buf, size_t count) | |
1da177e4 | 614 | { |
5136fa56 | 615 | int ret; |
1da177e4 LT |
616 | char str_governor[16]; |
617 | struct cpufreq_policy new_policy; | |
618 | ||
8fa5b631 | 619 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 620 | |
29464f28 | 621 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
622 | if (ret != 1) |
623 | return -EINVAL; | |
624 | ||
e08f5f5b GS |
625 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
626 | &new_policy.governor)) | |
1da177e4 LT |
627 | return -EINVAL; |
628 | ||
037ce839 | 629 | ret = cpufreq_set_policy(policy, &new_policy); |
88dc4384 | 630 | return ret ? ret : count; |
1da177e4 LT |
631 | } |
632 | ||
633 | /** | |
634 | * show_scaling_driver - show the cpufreq driver currently loaded | |
635 | */ | |
905d77cd | 636 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 637 | { |
1c3d85dd | 638 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
639 | } |
640 | ||
641 | /** | |
642 | * show_scaling_available_governors - show the available CPUfreq governors | |
643 | */ | |
905d77cd DJ |
644 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
645 | char *buf) | |
1da177e4 LT |
646 | { |
647 | ssize_t i = 0; | |
648 | struct cpufreq_governor *t; | |
649 | ||
9c0ebcf7 | 650 | if (!has_target()) { |
1da177e4 LT |
651 | i += sprintf(buf, "performance powersave"); |
652 | goto out; | |
653 | } | |
654 | ||
f7b27061 | 655 | for_each_governor(t) { |
29464f28 DJ |
656 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
657 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 658 | goto out; |
4b972f0b | 659 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 660 | } |
7d5e350f | 661 | out: |
1da177e4 LT |
662 | i += sprintf(&buf[i], "\n"); |
663 | return i; | |
664 | } | |
e8628dd0 | 665 | |
f4fd3797 | 666 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
667 | { |
668 | ssize_t i = 0; | |
669 | unsigned int cpu; | |
670 | ||
835481d9 | 671 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
672 | if (i) |
673 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
674 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
675 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 676 | break; |
1da177e4 LT |
677 | } |
678 | i += sprintf(&buf[i], "\n"); | |
679 | return i; | |
680 | } | |
f4fd3797 | 681 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 682 | |
e8628dd0 DW |
683 | /** |
684 | * show_related_cpus - show the CPUs affected by each transition even if | |
685 | * hw coordination is in use | |
686 | */ | |
687 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
688 | { | |
f4fd3797 | 689 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
690 | } |
691 | ||
692 | /** | |
693 | * show_affected_cpus - show the CPUs affected by each transition | |
694 | */ | |
695 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
696 | { | |
f4fd3797 | 697 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
698 | } |
699 | ||
9e76988e | 700 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 701 | const char *buf, size_t count) |
9e76988e VP |
702 | { |
703 | unsigned int freq = 0; | |
704 | unsigned int ret; | |
705 | ||
879000f9 | 706 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
707 | return -EINVAL; |
708 | ||
709 | ret = sscanf(buf, "%u", &freq); | |
710 | if (ret != 1) | |
711 | return -EINVAL; | |
712 | ||
713 | policy->governor->store_setspeed(policy, freq); | |
714 | ||
715 | return count; | |
716 | } | |
717 | ||
718 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
719 | { | |
879000f9 | 720 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
721 | return sprintf(buf, "<unsupported>\n"); |
722 | ||
723 | return policy->governor->show_setspeed(policy, buf); | |
724 | } | |
1da177e4 | 725 | |
e2f74f35 | 726 | /** |
8bf1ac72 | 727 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
728 | */ |
729 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
730 | { | |
731 | unsigned int limit; | |
732 | int ret; | |
1c3d85dd RW |
733 | if (cpufreq_driver->bios_limit) { |
734 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
735 | if (!ret) |
736 | return sprintf(buf, "%u\n", limit); | |
737 | } | |
738 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
739 | } | |
740 | ||
6dad2a29 BP |
741 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
742 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
743 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
744 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
745 | cpufreq_freq_attr_ro(scaling_available_governors); | |
746 | cpufreq_freq_attr_ro(scaling_driver); | |
747 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
748 | cpufreq_freq_attr_ro(bios_limit); | |
749 | cpufreq_freq_attr_ro(related_cpus); | |
750 | cpufreq_freq_attr_ro(affected_cpus); | |
751 | cpufreq_freq_attr_rw(scaling_min_freq); | |
752 | cpufreq_freq_attr_rw(scaling_max_freq); | |
753 | cpufreq_freq_attr_rw(scaling_governor); | |
754 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 755 | |
905d77cd | 756 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
757 | &cpuinfo_min_freq.attr, |
758 | &cpuinfo_max_freq.attr, | |
ed129784 | 759 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
760 | &scaling_min_freq.attr, |
761 | &scaling_max_freq.attr, | |
762 | &affected_cpus.attr, | |
e8628dd0 | 763 | &related_cpus.attr, |
1da177e4 LT |
764 | &scaling_governor.attr, |
765 | &scaling_driver.attr, | |
766 | &scaling_available_governors.attr, | |
9e76988e | 767 | &scaling_setspeed.attr, |
1da177e4 LT |
768 | NULL |
769 | }; | |
770 | ||
29464f28 DJ |
771 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
772 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 773 | |
29464f28 | 774 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 775 | { |
905d77cd DJ |
776 | struct cpufreq_policy *policy = to_policy(kobj); |
777 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 778 | ssize_t ret; |
6eed9404 | 779 | |
ad7722da | 780 | down_read(&policy->rwsem); |
6541aef0 | 781 | ret = fattr->show(policy, buf); |
ad7722da | 782 | up_read(&policy->rwsem); |
1b750e3b | 783 | |
1da177e4 LT |
784 | return ret; |
785 | } | |
786 | ||
905d77cd DJ |
787 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
788 | const char *buf, size_t count) | |
1da177e4 | 789 | { |
905d77cd DJ |
790 | struct cpufreq_policy *policy = to_policy(kobj); |
791 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 792 | ssize_t ret = -EINVAL; |
6eed9404 | 793 | |
4f750c93 SB |
794 | get_online_cpus(); |
795 | ||
6541aef0 RW |
796 | if (cpu_online(policy->cpu)) { |
797 | down_write(&policy->rwsem); | |
e08f5f5b | 798 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
799 | up_write(&policy->rwsem); |
800 | } | |
e08f5f5b | 801 | |
4f750c93 SB |
802 | put_online_cpus(); |
803 | ||
1da177e4 LT |
804 | return ret; |
805 | } | |
806 | ||
905d77cd | 807 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 808 | { |
905d77cd | 809 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 810 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
811 | complete(&policy->kobj_unregister); |
812 | } | |
813 | ||
52cf25d0 | 814 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
815 | .show = show, |
816 | .store = store, | |
817 | }; | |
818 | ||
819 | static struct kobj_type ktype_cpufreq = { | |
820 | .sysfs_ops = &sysfs_ops, | |
821 | .default_attrs = default_attrs, | |
822 | .release = cpufreq_sysfs_release, | |
823 | }; | |
824 | ||
87549141 VK |
825 | static int add_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) |
826 | { | |
827 | struct device *cpu_dev; | |
828 | ||
829 | pr_debug("%s: Adding symlink for CPU: %u\n", __func__, cpu); | |
830 | ||
831 | if (!policy) | |
832 | return 0; | |
833 | ||
834 | cpu_dev = get_cpu_device(cpu); | |
835 | if (WARN_ON(!cpu_dev)) | |
836 | return 0; | |
837 | ||
838 | return sysfs_create_link(&cpu_dev->kobj, &policy->kobj, "cpufreq"); | |
839 | } | |
840 | ||
841 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) | |
842 | { | |
843 | struct device *cpu_dev; | |
844 | ||
845 | pr_debug("%s: Removing symlink for CPU: %u\n", __func__, cpu); | |
846 | ||
847 | cpu_dev = get_cpu_device(cpu); | |
848 | if (WARN_ON(!cpu_dev)) | |
849 | return; | |
850 | ||
851 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); | |
852 | } | |
853 | ||
854 | /* Add/remove symlinks for all related CPUs */ | |
308b60e7 | 855 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
856 | { |
857 | unsigned int j; | |
858 | int ret = 0; | |
859 | ||
87549141 | 860 | /* Some related CPUs might not be present (physically hotplugged) */ |
559ed407 | 861 | for_each_cpu(j, policy->real_cpus) { |
87549141 | 862 | ret = add_cpu_dev_symlink(policy, j); |
71c3461e RW |
863 | if (ret) |
864 | break; | |
19d6f7ec | 865 | } |
87549141 | 866 | |
19d6f7ec DJ |
867 | return ret; |
868 | } | |
869 | ||
87549141 VK |
870 | static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy) |
871 | { | |
872 | unsigned int j; | |
873 | ||
874 | /* Some related CPUs might not be present (physically hotplugged) */ | |
96bdda61 | 875 | for_each_cpu(j, policy->real_cpus) |
87549141 | 876 | remove_cpu_dev_symlink(policy, j); |
87549141 VK |
877 | } |
878 | ||
d9612a49 | 879 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
880 | { |
881 | struct freq_attr **drv_attr; | |
909a694e | 882 | int ret = 0; |
909a694e | 883 | |
909a694e | 884 | /* set up files for this cpu device */ |
1c3d85dd | 885 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 886 | while (drv_attr && *drv_attr) { |
909a694e DJ |
887 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
888 | if (ret) | |
6d4e81ed | 889 | return ret; |
909a694e DJ |
890 | drv_attr++; |
891 | } | |
1c3d85dd | 892 | if (cpufreq_driver->get) { |
909a694e DJ |
893 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
894 | if (ret) | |
6d4e81ed | 895 | return ret; |
909a694e | 896 | } |
c034b02e DB |
897 | |
898 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
899 | if (ret) | |
6d4e81ed | 900 | return ret; |
c034b02e | 901 | |
1c3d85dd | 902 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
903 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
904 | if (ret) | |
6d4e81ed | 905 | return ret; |
e2f74f35 | 906 | } |
909a694e | 907 | |
6d4e81ed | 908 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
909 | } |
910 | ||
de1df26b RW |
911 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
912 | { | |
913 | return NULL; | |
914 | } | |
915 | ||
7f0fa40f | 916 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 917 | { |
6e2c89d1 | 918 | struct cpufreq_governor *gov = NULL; |
e18f1682 | 919 | struct cpufreq_policy new_policy; |
e18f1682 | 920 | |
d5b73cd8 | 921 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 922 | |
6e2c89d1 | 923 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 924 | gov = find_governor(policy->last_governor); |
de1df26b | 925 | if (gov) { |
6e2c89d1 | 926 | pr_debug("Restoring governor %s for cpu %d\n", |
927 | policy->governor->name, policy->cpu); | |
de1df26b RW |
928 | } else { |
929 | gov = cpufreq_default_governor(); | |
930 | if (!gov) | |
931 | return -ENODATA; | |
932 | } | |
6e2c89d1 | 933 | |
934 | new_policy.governor = gov; | |
935 | ||
69030dd1 SP |
936 | /* Use the default policy if there is no last_policy. */ |
937 | if (cpufreq_driver->setpolicy) { | |
938 | if (policy->last_policy) | |
939 | new_policy.policy = policy->last_policy; | |
940 | else | |
941 | cpufreq_parse_governor(gov->name, &new_policy.policy, | |
942 | NULL); | |
943 | } | |
ecf7e461 | 944 | /* set default policy */ |
7f0fa40f | 945 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
946 | } |
947 | ||
d9612a49 | 948 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 949 | { |
9c0ebcf7 | 950 | int ret = 0; |
fcf80582 | 951 | |
bb29ae15 VK |
952 | /* Has this CPU been taken care of already? */ |
953 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
954 | return 0; | |
955 | ||
49f18560 | 956 | down_write(&policy->rwsem); |
9c0ebcf7 | 957 | if (has_target()) { |
a1317e09 | 958 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
3de9bdeb VK |
959 | if (ret) { |
960 | pr_err("%s: Failed to stop governor\n", __func__); | |
49f18560 | 961 | goto unlock; |
3de9bdeb VK |
962 | } |
963 | } | |
fcf80582 | 964 | |
fcf80582 | 965 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 966 | |
9c0ebcf7 | 967 | if (has_target()) { |
0a300767 | 968 | ret = cpufreq_start_governor(policy); |
49f18560 | 969 | if (ret) |
3de9bdeb | 970 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 971 | } |
fcf80582 | 972 | |
49f18560 VK |
973 | unlock: |
974 | up_write(&policy->rwsem); | |
975 | return ret; | |
fcf80582 | 976 | } |
1da177e4 | 977 | |
11eb69b9 VK |
978 | static void handle_update(struct work_struct *work) |
979 | { | |
980 | struct cpufreq_policy *policy = | |
981 | container_of(work, struct cpufreq_policy, update); | |
982 | unsigned int cpu = policy->cpu; | |
983 | pr_debug("handle_update for cpu %u called\n", cpu); | |
984 | cpufreq_update_policy(cpu); | |
fcf80582 | 985 | } |
1da177e4 | 986 | |
a34e63b1 | 987 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 | 988 | { |
a34e63b1 | 989 | struct device *dev = get_cpu_device(cpu); |
e9698cc5 | 990 | struct cpufreq_policy *policy; |
edd4a893 | 991 | int ret; |
e9698cc5 | 992 | |
a34e63b1 RW |
993 | if (WARN_ON(!dev)) |
994 | return NULL; | |
995 | ||
e9698cc5 SB |
996 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
997 | if (!policy) | |
998 | return NULL; | |
999 | ||
1000 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1001 | goto err_free_policy; | |
1002 | ||
1003 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1004 | goto err_free_cpumask; | |
1005 | ||
559ed407 RW |
1006 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1007 | goto err_free_rcpumask; | |
1008 | ||
edd4a893 VK |
1009 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1010 | cpufreq_global_kobject, "policy%u", cpu); | |
1011 | if (ret) { | |
1012 | pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); | |
1013 | goto err_free_real_cpus; | |
1014 | } | |
1015 | ||
c88a1f8b | 1016 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1017 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1018 | spin_lock_init(&policy->transition_lock); |
1019 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1020 | init_completion(&policy->kobj_unregister); |
1021 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1022 | |
a34e63b1 | 1023 | policy->cpu = cpu; |
e9698cc5 SB |
1024 | return policy; |
1025 | ||
edd4a893 VK |
1026 | err_free_real_cpus: |
1027 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1028 | err_free_rcpumask: |
1029 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1030 | err_free_cpumask: |
1031 | free_cpumask_var(policy->cpus); | |
1032 | err_free_policy: | |
1033 | kfree(policy); | |
1034 | ||
1035 | return NULL; | |
1036 | } | |
1037 | ||
2fc3384d | 1038 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify) |
42f921a6 VK |
1039 | { |
1040 | struct kobject *kobj; | |
1041 | struct completion *cmp; | |
1042 | ||
2fc3384d VK |
1043 | if (notify) |
1044 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1045 | CPUFREQ_REMOVE_POLICY, policy); | |
fcd7af91 | 1046 | |
87549141 VK |
1047 | down_write(&policy->rwsem); |
1048 | cpufreq_remove_dev_symlink(policy); | |
42f921a6 VK |
1049 | kobj = &policy->kobj; |
1050 | cmp = &policy->kobj_unregister; | |
87549141 | 1051 | up_write(&policy->rwsem); |
42f921a6 VK |
1052 | kobject_put(kobj); |
1053 | ||
1054 | /* | |
1055 | * We need to make sure that the underlying kobj is | |
1056 | * actually not referenced anymore by anybody before we | |
1057 | * proceed with unloading. | |
1058 | */ | |
1059 | pr_debug("waiting for dropping of refcount\n"); | |
1060 | wait_for_completion(cmp); | |
1061 | pr_debug("wait complete\n"); | |
1062 | } | |
1063 | ||
3654c5cc | 1064 | static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify) |
e9698cc5 | 1065 | { |
988bed09 VK |
1066 | unsigned long flags; |
1067 | int cpu; | |
1068 | ||
1069 | /* Remove policy from list */ | |
1070 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1071 | list_del(&policy->policy_list); | |
1072 | ||
1073 | for_each_cpu(cpu, policy->related_cpus) | |
1074 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1075 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1076 | ||
3654c5cc | 1077 | cpufreq_policy_put_kobj(policy, notify); |
559ed407 | 1078 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1079 | free_cpumask_var(policy->related_cpus); |
1080 | free_cpumask_var(policy->cpus); | |
1081 | kfree(policy); | |
1082 | } | |
1083 | ||
0b275352 | 1084 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1085 | { |
7f0c020a | 1086 | struct cpufreq_policy *policy; |
194d99c7 | 1087 | bool new_policy; |
1da177e4 | 1088 | unsigned long flags; |
0b275352 RW |
1089 | unsigned int j; |
1090 | int ret; | |
87549141 | 1091 | |
0b275352 | 1092 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1093 | |
bb29ae15 | 1094 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1095 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1096 | if (policy) { |
9104bb26 | 1097 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1098 | if (!policy_is_inactive(policy)) |
d9612a49 | 1099 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1100 | |
11ce707e | 1101 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1102 | new_policy = false; |
11ce707e RW |
1103 | down_write(&policy->rwsem); |
1104 | policy->cpu = cpu; | |
1105 | policy->governor = NULL; | |
1106 | up_write(&policy->rwsem); | |
1107 | } else { | |
194d99c7 | 1108 | new_policy = true; |
a34e63b1 | 1109 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1110 | if (!policy) |
d4d854d6 | 1111 | return -ENOMEM; |
72368d12 | 1112 | } |
0d66b91e | 1113 | |
835481d9 | 1114 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1115 | |
1da177e4 LT |
1116 | /* call driver. From then on the cpufreq must be able |
1117 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1118 | */ | |
1c3d85dd | 1119 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1120 | if (ret) { |
2d06d8c4 | 1121 | pr_debug("initialization failed\n"); |
8101f997 | 1122 | goto out_free_policy; |
1da177e4 | 1123 | } |
643ae6e8 | 1124 | |
6d4e81ed TV |
1125 | down_write(&policy->rwsem); |
1126 | ||
194d99c7 | 1127 | if (new_policy) { |
4d1f3a5b | 1128 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1129 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1130 | /* Remember CPUs present at the policy creation time. */ |
559ed407 | 1131 | cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask); |
4d1f3a5b | 1132 | } |
559ed407 | 1133 | |
5a7e56a5 VK |
1134 | /* |
1135 | * affected cpus must always be the one, which are online. We aren't | |
1136 | * managing offline cpus here. | |
1137 | */ | |
1138 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1139 | ||
194d99c7 | 1140 | if (new_policy) { |
5a7e56a5 VK |
1141 | policy->user_policy.min = policy->min; |
1142 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1143 | |
988bed09 VK |
1144 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1145 | for_each_cpu(j, policy->related_cpus) | |
1146 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1147 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1148 | } | |
652ed95d | 1149 | |
2ed99e39 | 1150 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1151 | policy->cur = cpufreq_driver->get(policy->cpu); |
1152 | if (!policy->cur) { | |
1153 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1154 | goto out_exit_policy; |
da60ce9f VK |
1155 | } |
1156 | } | |
1157 | ||
d3916691 VK |
1158 | /* |
1159 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1160 | * frequency table present with cpufreq core. In such cases CPU might be | |
1161 | * unstable if it has to run on that frequency for long duration of time | |
1162 | * and so its better to set it to a frequency which is specified in | |
1163 | * freq-table. This also makes cpufreq stats inconsistent as | |
1164 | * cpufreq-stats would fail to register because current frequency of CPU | |
1165 | * isn't found in freq-table. | |
1166 | * | |
1167 | * Because we don't want this change to effect boot process badly, we go | |
1168 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1169 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1170 | * is initialized to zero). | |
1171 | * | |
1172 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1173 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1174 | * equal to target-freq. | |
1175 | */ | |
1176 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1177 | && has_target()) { | |
1178 | /* Are we running at unknown frequency ? */ | |
1179 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1180 | if (ret == -EINVAL) { | |
1181 | /* Warn user and fix it */ | |
1182 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1183 | __func__, policy->cpu, policy->cur); | |
1184 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1185 | CPUFREQ_RELATION_L); | |
1186 | ||
1187 | /* | |
1188 | * Reaching here after boot in a few seconds may not | |
1189 | * mean that system will remain stable at "unknown" | |
1190 | * frequency for longer duration. Hence, a BUG_ON(). | |
1191 | */ | |
1192 | BUG_ON(ret); | |
1193 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1194 | __func__, policy->cpu, policy->cur); | |
1195 | } | |
1196 | } | |
1197 | ||
a1531acd TR |
1198 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1199 | CPUFREQ_START, policy); | |
1200 | ||
194d99c7 | 1201 | if (new_policy) { |
d9612a49 | 1202 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1203 | if (ret) |
8101f997 | 1204 | goto out_exit_policy; |
fcd7af91 VK |
1205 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1206 | CPUFREQ_CREATE_POLICY, policy); | |
8ff69732 | 1207 | |
988bed09 VK |
1208 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1209 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1210 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1211 | } | |
9515f4d6 | 1212 | |
7f0fa40f VK |
1213 | ret = cpufreq_init_policy(policy); |
1214 | if (ret) { | |
1215 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1216 | __func__, cpu, ret); | |
194d99c7 RW |
1217 | /* cpufreq_policy_free() will notify based on this */ |
1218 | new_policy = false; | |
1219 | goto out_exit_policy; | |
08fd8c1c | 1220 | } |
e18f1682 | 1221 | |
4e97b631 | 1222 | up_write(&policy->rwsem); |
08fd8c1c | 1223 | |
038c5b3e | 1224 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1225 | |
7c45cf31 VK |
1226 | /* Callback for handling stuff after policy is ready */ |
1227 | if (cpufreq_driver->ready) | |
1228 | cpufreq_driver->ready(policy); | |
1229 | ||
2d06d8c4 | 1230 | pr_debug("initialization complete\n"); |
87c32271 | 1231 | |
1da177e4 LT |
1232 | return 0; |
1233 | ||
8101f997 | 1234 | out_exit_policy: |
7106e02b PB |
1235 | up_write(&policy->rwsem); |
1236 | ||
da60ce9f VK |
1237 | if (cpufreq_driver->exit) |
1238 | cpufreq_driver->exit(policy); | |
8101f997 | 1239 | out_free_policy: |
194d99c7 | 1240 | cpufreq_policy_free(policy, !new_policy); |
1da177e4 LT |
1241 | return ret; |
1242 | } | |
1243 | ||
0b275352 RW |
1244 | /** |
1245 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1246 | * @dev: CPU device. | |
1247 | * @sif: Subsystem interface structure pointer (not used) | |
1248 | */ | |
1249 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1250 | { | |
1251 | unsigned cpu = dev->id; | |
1252 | int ret; | |
1253 | ||
1254 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1255 | ||
1256 | if (cpu_online(cpu)) { | |
1257 | ret = cpufreq_online(cpu); | |
1258 | } else { | |
1259 | /* | |
1260 | * A hotplug notifier will follow and we will handle it as CPU | |
1261 | * online then. For now, just create the sysfs link, unless | |
1262 | * there is no policy or the link is already present. | |
1263 | */ | |
1264 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
1265 | ||
1266 | ret = policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus) | |
1267 | ? add_cpu_dev_symlink(policy, cpu) : 0; | |
1268 | } | |
6eed9404 | 1269 | |
1da177e4 LT |
1270 | return ret; |
1271 | } | |
1272 | ||
69cee714 | 1273 | static void cpufreq_offline(unsigned int cpu) |
1da177e4 | 1274 | { |
3a3e9e06 | 1275 | struct cpufreq_policy *policy; |
69cee714 | 1276 | int ret; |
1da177e4 | 1277 | |
b8eed8af | 1278 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1279 | |
988bed09 | 1280 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1281 | if (!policy) { |
b8eed8af | 1282 | pr_debug("%s: No cpu_data found\n", __func__); |
15c0b4d2 | 1283 | return; |
1da177e4 | 1284 | } |
1da177e4 | 1285 | |
49f18560 | 1286 | down_write(&policy->rwsem); |
9c0ebcf7 | 1287 | if (has_target()) { |
a1317e09 | 1288 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
559ed407 | 1289 | if (ret) |
3de9bdeb | 1290 | pr_err("%s: Failed to stop governor\n", __func__); |
db5f2995 | 1291 | } |
1da177e4 | 1292 | |
9591becb | 1293 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1294 | |
9591becb VK |
1295 | if (policy_is_inactive(policy)) { |
1296 | if (has_target()) | |
1297 | strncpy(policy->last_governor, policy->governor->name, | |
1298 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1299 | else |
1300 | policy->last_policy = policy->policy; | |
9591becb VK |
1301 | } else if (cpu == policy->cpu) { |
1302 | /* Nominate new CPU */ | |
1303 | policy->cpu = cpumask_any(policy->cpus); | |
1304 | } | |
084f3493 | 1305 | |
9591becb VK |
1306 | /* Start governor again for active policy */ |
1307 | if (!policy_is_inactive(policy)) { | |
1308 | if (has_target()) { | |
0a300767 | 1309 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1310 | if (ret) |
1311 | pr_err("%s: Failed to start governor\n", __func__); | |
1312 | } | |
cedb70af | 1313 | |
49f18560 | 1314 | goto unlock; |
cedb70af SB |
1315 | } |
1316 | ||
69cee714 VK |
1317 | if (cpufreq_driver->stop_cpu) |
1318 | cpufreq_driver->stop_cpu(policy); | |
87549141 VK |
1319 | |
1320 | /* If cpu is last user of policy, free policy */ | |
1321 | if (has_target()) { | |
a1317e09 | 1322 | ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
559ed407 | 1323 | if (ret) |
87549141 | 1324 | pr_err("%s: Failed to exit governor\n", __func__); |
27ecddc2 | 1325 | } |
1da177e4 | 1326 | |
87549141 VK |
1327 | /* |
1328 | * Perform the ->exit() even during light-weight tear-down, | |
1329 | * since this is a core component, and is essential for the | |
1330 | * subsequent light-weight ->init() to succeed. | |
1331 | */ | |
55582bcc | 1332 | if (cpufreq_driver->exit) { |
87549141 | 1333 | cpufreq_driver->exit(policy); |
55582bcc SP |
1334 | policy->freq_table = NULL; |
1335 | } | |
49f18560 VK |
1336 | |
1337 | unlock: | |
1338 | up_write(&policy->rwsem); | |
1da177e4 LT |
1339 | } |
1340 | ||
cedb70af | 1341 | /** |
27a862e9 | 1342 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1343 | * |
1344 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1345 | */ |
71db87ba | 1346 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1347 | { |
8a25a2fd | 1348 | unsigned int cpu = dev->id; |
559ed407 | 1349 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1350 | |
559ed407 | 1351 | if (!policy) |
1af115d6 | 1352 | return; |
87549141 | 1353 | |
69cee714 VK |
1354 | if (cpu_online(cpu)) |
1355 | cpufreq_offline(cpu); | |
87549141 | 1356 | |
559ed407 | 1357 | cpumask_clear_cpu(cpu, policy->real_cpus); |
f344dae0 | 1358 | remove_cpu_dev_symlink(policy, cpu); |
87549141 | 1359 | |
f344dae0 | 1360 | if (cpumask_empty(policy->real_cpus)) |
3654c5cc | 1361 | cpufreq_policy_free(policy, true); |
5a01f2e8 VP |
1362 | } |
1363 | ||
1da177e4 | 1364 | /** |
bb176f7d VK |
1365 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1366 | * in deep trouble. | |
a1e1dc41 | 1367 | * @policy: policy managing CPUs |
1da177e4 LT |
1368 | * @new_freq: CPU frequency the CPU actually runs at |
1369 | * | |
29464f28 DJ |
1370 | * We adjust to current frequency first, and need to clean up later. |
1371 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1372 | */ |
a1e1dc41 | 1373 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1374 | unsigned int new_freq) |
1da177e4 LT |
1375 | { |
1376 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1377 | |
e837f9b5 | 1378 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1379 | policy->cur, new_freq); |
1da177e4 | 1380 | |
a1e1dc41 | 1381 | freqs.old = policy->cur; |
1da177e4 | 1382 | freqs.new = new_freq; |
b43a7ffb | 1383 | |
8fec051e VK |
1384 | cpufreq_freq_transition_begin(policy, &freqs); |
1385 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1386 | } |
1387 | ||
32ee8c3e | 1388 | /** |
4ab70df4 | 1389 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1390 | * @cpu: CPU number |
1391 | * | |
1392 | * This is the last known freq, without actually getting it from the driver. | |
1393 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1394 | */ | |
1395 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1396 | { | |
9e21ba8b | 1397 | struct cpufreq_policy *policy; |
e08f5f5b | 1398 | unsigned int ret_freq = 0; |
c75361c0 | 1399 | unsigned long flags; |
95235ca2 | 1400 | |
c75361c0 RC |
1401 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1402 | ||
1403 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1404 | ret_freq = cpufreq_driver->get(cpu); | |
1405 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1406 | return ret_freq; | |
1407 | } | |
1408 | ||
1409 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1410 | |
1411 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1412 | if (policy) { |
e08f5f5b | 1413 | ret_freq = policy->cur; |
95235ca2 VP |
1414 | cpufreq_cpu_put(policy); |
1415 | } | |
1416 | ||
4d34a67d | 1417 | return ret_freq; |
95235ca2 VP |
1418 | } |
1419 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1420 | ||
3d737108 JB |
1421 | /** |
1422 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1423 | * @cpu: CPU number | |
1424 | * | |
1425 | * Just return the max possible frequency for a given CPU. | |
1426 | */ | |
1427 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1428 | { | |
1429 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1430 | unsigned int ret_freq = 0; | |
1431 | ||
1432 | if (policy) { | |
1433 | ret_freq = policy->max; | |
1434 | cpufreq_cpu_put(policy); | |
1435 | } | |
1436 | ||
1437 | return ret_freq; | |
1438 | } | |
1439 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1440 | ||
d92d50a4 | 1441 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1442 | { |
e08f5f5b | 1443 | unsigned int ret_freq = 0; |
5800043b | 1444 | |
1c3d85dd | 1445 | if (!cpufreq_driver->get) |
4d34a67d | 1446 | return ret_freq; |
1da177e4 | 1447 | |
d92d50a4 | 1448 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1449 | |
11e584cf VK |
1450 | /* Updating inactive policies is invalid, so avoid doing that. */ |
1451 | if (unlikely(policy_is_inactive(policy))) | |
1452 | return ret_freq; | |
1453 | ||
e08f5f5b | 1454 | if (ret_freq && policy->cur && |
1c3d85dd | 1455 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1456 | /* verify no discrepancy between actual and |
1457 | saved value exists */ | |
1458 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1459 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1460 | schedule_work(&policy->update); |
1461 | } | |
1462 | } | |
1463 | ||
4d34a67d | 1464 | return ret_freq; |
5a01f2e8 | 1465 | } |
1da177e4 | 1466 | |
5a01f2e8 VP |
1467 | /** |
1468 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1469 | * @cpu: CPU number | |
1470 | * | |
1471 | * Get the CPU current (static) CPU frequency | |
1472 | */ | |
1473 | unsigned int cpufreq_get(unsigned int cpu) | |
1474 | { | |
999976e0 | 1475 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1476 | unsigned int ret_freq = 0; |
5a01f2e8 | 1477 | |
999976e0 AP |
1478 | if (policy) { |
1479 | down_read(&policy->rwsem); | |
d92d50a4 | 1480 | ret_freq = __cpufreq_get(policy); |
999976e0 | 1481 | up_read(&policy->rwsem); |
5a01f2e8 | 1482 | |
999976e0 AP |
1483 | cpufreq_cpu_put(policy); |
1484 | } | |
6eed9404 | 1485 | |
4d34a67d | 1486 | return ret_freq; |
1da177e4 LT |
1487 | } |
1488 | EXPORT_SYMBOL(cpufreq_get); | |
1489 | ||
999f5729 RW |
1490 | static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy) |
1491 | { | |
1492 | unsigned int new_freq; | |
1493 | ||
c9d9c929 RW |
1494 | if (cpufreq_suspended) |
1495 | return 0; | |
1496 | ||
999f5729 RW |
1497 | new_freq = cpufreq_driver->get(policy->cpu); |
1498 | if (!new_freq) | |
1499 | return 0; | |
1500 | ||
1501 | if (!policy->cur) { | |
1502 | pr_debug("cpufreq: Driver did not initialize current freq\n"); | |
1503 | policy->cur = new_freq; | |
1504 | } else if (policy->cur != new_freq && has_target()) { | |
1505 | cpufreq_out_of_sync(policy, new_freq); | |
1506 | } | |
1507 | ||
1508 | return new_freq; | |
1509 | } | |
1510 | ||
8a25a2fd KS |
1511 | static struct subsys_interface cpufreq_interface = { |
1512 | .name = "cpufreq", | |
1513 | .subsys = &cpu_subsys, | |
1514 | .add_dev = cpufreq_add_dev, | |
1515 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1516 | }; |
1517 | ||
e28867ea VK |
1518 | /* |
1519 | * In case platform wants some specific frequency to be configured | |
1520 | * during suspend.. | |
1521 | */ | |
1522 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1523 | { | |
1524 | int ret; | |
1525 | ||
1526 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1527 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1528 | return 0; | |
e28867ea VK |
1529 | } |
1530 | ||
1531 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1532 | policy->suspend_freq); | |
1533 | ||
1534 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1535 | CPUFREQ_RELATION_H); | |
1536 | if (ret) | |
1537 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1538 | __func__, policy->suspend_freq, ret); | |
1539 | ||
1540 | return ret; | |
1541 | } | |
1542 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1543 | ||
42d4dc3f | 1544 | /** |
2f0aea93 | 1545 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1546 | * |
2f0aea93 VK |
1547 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1548 | * as some platforms can't change frequency after this point in suspend cycle. | |
1549 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1550 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1551 | */ |
2f0aea93 | 1552 | void cpufreq_suspend(void) |
42d4dc3f | 1553 | { |
3a3e9e06 | 1554 | struct cpufreq_policy *policy; |
49f18560 | 1555 | int ret; |
42d4dc3f | 1556 | |
2f0aea93 VK |
1557 | if (!cpufreq_driver) |
1558 | return; | |
42d4dc3f | 1559 | |
2f0aea93 | 1560 | if (!has_target()) |
b1b12bab | 1561 | goto suspend; |
42d4dc3f | 1562 | |
2f0aea93 VK |
1563 | pr_debug("%s: Suspending Governors\n", __func__); |
1564 | ||
f963735a | 1565 | for_each_active_policy(policy) { |
49f18560 | 1566 | down_write(&policy->rwsem); |
a1317e09 | 1567 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
49f18560 VK |
1568 | up_write(&policy->rwsem); |
1569 | ||
1570 | if (ret) | |
2f0aea93 VK |
1571 | pr_err("%s: Failed to stop governor for policy: %p\n", |
1572 | __func__, policy); | |
1573 | else if (cpufreq_driver->suspend | |
1574 | && cpufreq_driver->suspend(policy)) | |
1575 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1576 | policy); | |
42d4dc3f | 1577 | } |
b1b12bab VK |
1578 | |
1579 | suspend: | |
1580 | cpufreq_suspended = true; | |
42d4dc3f BH |
1581 | } |
1582 | ||
1da177e4 | 1583 | /** |
2f0aea93 | 1584 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1585 | * |
2f0aea93 VK |
1586 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1587 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1588 | */ |
2f0aea93 | 1589 | void cpufreq_resume(void) |
1da177e4 | 1590 | { |
3a3e9e06 | 1591 | struct cpufreq_policy *policy; |
49f18560 | 1592 | int ret; |
1da177e4 | 1593 | |
2f0aea93 VK |
1594 | if (!cpufreq_driver) |
1595 | return; | |
1da177e4 | 1596 | |
8e30444e LT |
1597 | cpufreq_suspended = false; |
1598 | ||
2f0aea93 | 1599 | if (!has_target()) |
e00e56df | 1600 | return; |
1da177e4 | 1601 | |
2f0aea93 | 1602 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1603 | |
f963735a | 1604 | for_each_active_policy(policy) { |
49f18560 | 1605 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1606 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1607 | policy); | |
49f18560 VK |
1608 | } else { |
1609 | down_write(&policy->rwsem); | |
0a300767 | 1610 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1611 | up_write(&policy->rwsem); |
1612 | ||
1613 | if (ret) | |
1614 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1615 | __func__, policy); | |
1616 | } | |
2f0aea93 VK |
1617 | } |
1618 | } | |
1da177e4 | 1619 | |
9d95046e BP |
1620 | /** |
1621 | * cpufreq_get_current_driver - return current driver's name | |
1622 | * | |
1623 | * Return the name string of the currently loaded cpufreq driver | |
1624 | * or NULL, if none. | |
1625 | */ | |
1626 | const char *cpufreq_get_current_driver(void) | |
1627 | { | |
1c3d85dd RW |
1628 | if (cpufreq_driver) |
1629 | return cpufreq_driver->name; | |
1630 | ||
1631 | return NULL; | |
9d95046e BP |
1632 | } |
1633 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1634 | |
51315cdf TP |
1635 | /** |
1636 | * cpufreq_get_driver_data - return current driver data | |
1637 | * | |
1638 | * Return the private data of the currently loaded cpufreq | |
1639 | * driver, or NULL if no cpufreq driver is loaded. | |
1640 | */ | |
1641 | void *cpufreq_get_driver_data(void) | |
1642 | { | |
1643 | if (cpufreq_driver) | |
1644 | return cpufreq_driver->driver_data; | |
1645 | ||
1646 | return NULL; | |
1647 | } | |
1648 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1649 | ||
1da177e4 LT |
1650 | /********************************************************************* |
1651 | * NOTIFIER LISTS INTERFACE * | |
1652 | *********************************************************************/ | |
1653 | ||
1654 | /** | |
1655 | * cpufreq_register_notifier - register a driver with cpufreq | |
1656 | * @nb: notifier function to register | |
1657 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1658 | * | |
32ee8c3e | 1659 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1660 | * are notified about clock rate changes (once before and once after |
1661 | * the transition), or a list of drivers that are notified about | |
1662 | * changes in cpufreq policy. | |
1663 | * | |
1664 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1665 | * blocking_notifier_chain_register. |
1da177e4 LT |
1666 | */ |
1667 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1668 | { | |
1669 | int ret; | |
1670 | ||
d5aaffa9 DB |
1671 | if (cpufreq_disabled()) |
1672 | return -EINVAL; | |
1673 | ||
74212ca4 CEB |
1674 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1675 | ||
1da177e4 LT |
1676 | switch (list) { |
1677 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1678 | ret = srcu_notifier_chain_register( |
e041c683 | 1679 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1680 | break; |
1681 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1682 | ret = blocking_notifier_chain_register( |
1683 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1684 | break; |
1685 | default: | |
1686 | ret = -EINVAL; | |
1687 | } | |
1da177e4 LT |
1688 | |
1689 | return ret; | |
1690 | } | |
1691 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1692 | ||
1da177e4 LT |
1693 | /** |
1694 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1695 | * @nb: notifier block to be unregistered | |
bb176f7d | 1696 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1697 | * |
1698 | * Remove a driver from the CPU frequency notifier list. | |
1699 | * | |
1700 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1701 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1702 | */ |
1703 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1704 | { | |
1705 | int ret; | |
1706 | ||
d5aaffa9 DB |
1707 | if (cpufreq_disabled()) |
1708 | return -EINVAL; | |
1709 | ||
1da177e4 LT |
1710 | switch (list) { |
1711 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1712 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1713 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1714 | break; |
1715 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1716 | ret = blocking_notifier_chain_unregister( |
1717 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1718 | break; |
1719 | default: | |
1720 | ret = -EINVAL; | |
1721 | } | |
1da177e4 LT |
1722 | |
1723 | return ret; | |
1724 | } | |
1725 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1726 | ||
1727 | ||
1728 | /********************************************************************* | |
1729 | * GOVERNORS * | |
1730 | *********************************************************************/ | |
1731 | ||
1c03a2d0 VK |
1732 | /* Must set freqs->new to intermediate frequency */ |
1733 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1734 | struct cpufreq_freqs *freqs, int index) | |
1735 | { | |
1736 | int ret; | |
1737 | ||
1738 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1739 | ||
1740 | /* We don't need to switch to intermediate freq */ | |
1741 | if (!freqs->new) | |
1742 | return 0; | |
1743 | ||
1744 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1745 | __func__, policy->cpu, freqs->old, freqs->new); | |
1746 | ||
1747 | cpufreq_freq_transition_begin(policy, freqs); | |
1748 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1749 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1750 | ||
1751 | if (ret) | |
1752 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1753 | __func__, ret); | |
1754 | ||
1755 | return ret; | |
1756 | } | |
1757 | ||
8d65775d VK |
1758 | static int __target_index(struct cpufreq_policy *policy, |
1759 | struct cpufreq_frequency_table *freq_table, int index) | |
1760 | { | |
1c03a2d0 VK |
1761 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1762 | unsigned int intermediate_freq = 0; | |
8d65775d VK |
1763 | int retval = -EINVAL; |
1764 | bool notify; | |
1765 | ||
1766 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
8d65775d | 1767 | if (notify) { |
1c03a2d0 VK |
1768 | /* Handle switching to intermediate frequency */ |
1769 | if (cpufreq_driver->get_intermediate) { | |
1770 | retval = __target_intermediate(policy, &freqs, index); | |
1771 | if (retval) | |
1772 | return retval; | |
1773 | ||
1774 | intermediate_freq = freqs.new; | |
1775 | /* Set old freq to intermediate */ | |
1776 | if (intermediate_freq) | |
1777 | freqs.old = freqs.new; | |
1778 | } | |
8d65775d | 1779 | |
1c03a2d0 | 1780 | freqs.new = freq_table[index].frequency; |
8d65775d VK |
1781 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1782 | __func__, policy->cpu, freqs.old, freqs.new); | |
1783 | ||
1784 | cpufreq_freq_transition_begin(policy, &freqs); | |
1785 | } | |
1786 | ||
1787 | retval = cpufreq_driver->target_index(policy, index); | |
1788 | if (retval) | |
1789 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1790 | retval); | |
1791 | ||
1c03a2d0 | 1792 | if (notify) { |
8d65775d VK |
1793 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1794 | ||
1c03a2d0 VK |
1795 | /* |
1796 | * Failed after setting to intermediate freq? Driver should have | |
1797 | * reverted back to initial frequency and so should we. Check | |
1798 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1799 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1800 | */ |
1801 | if (unlikely(retval && intermediate_freq)) { | |
1802 | freqs.old = intermediate_freq; | |
1803 | freqs.new = policy->restore_freq; | |
1804 | cpufreq_freq_transition_begin(policy, &freqs); | |
1805 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1806 | } | |
1807 | } | |
1808 | ||
8d65775d VK |
1809 | return retval; |
1810 | } | |
1811 | ||
1da177e4 LT |
1812 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1813 | unsigned int target_freq, | |
1814 | unsigned int relation) | |
1815 | { | |
7249924e | 1816 | unsigned int old_target_freq = target_freq; |
6019d23a RW |
1817 | struct cpufreq_frequency_table *freq_table; |
1818 | int index, retval; | |
c32b6b8e | 1819 | |
a7b422cd KRW |
1820 | if (cpufreq_disabled()) |
1821 | return -ENODEV; | |
1822 | ||
7249924e VK |
1823 | /* Make sure that target_freq is within supported range */ |
1824 | if (target_freq > policy->max) | |
1825 | target_freq = policy->max; | |
1826 | if (target_freq < policy->min) | |
1827 | target_freq = policy->min; | |
1828 | ||
1829 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1830 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1831 | |
9c0ebcf7 VK |
1832 | /* |
1833 | * This might look like a redundant call as we are checking it again | |
1834 | * after finding index. But it is left intentionally for cases where | |
1835 | * exactly same freq is called again and so we can save on few function | |
1836 | * calls. | |
1837 | */ | |
5a1c0228 VK |
1838 | if (target_freq == policy->cur) |
1839 | return 0; | |
1840 | ||
1c03a2d0 VK |
1841 | /* Save last value to restore later on errors */ |
1842 | policy->restore_freq = policy->cur; | |
1843 | ||
1c3d85dd | 1844 | if (cpufreq_driver->target) |
6019d23a | 1845 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 1846 | |
6019d23a RW |
1847 | if (!cpufreq_driver->target_index) |
1848 | return -EINVAL; | |
9c0ebcf7 | 1849 | |
6019d23a RW |
1850 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
1851 | if (unlikely(!freq_table)) { | |
1852 | pr_err("%s: Unable to find freq_table\n", __func__); | |
1853 | return -EINVAL; | |
1854 | } | |
d4019f0a | 1855 | |
6019d23a RW |
1856 | retval = cpufreq_frequency_table_target(policy, freq_table, target_freq, |
1857 | relation, &index); | |
1858 | if (unlikely(retval)) { | |
1859 | pr_err("%s: Unable to find matching freq\n", __func__); | |
1860 | return retval; | |
9c0ebcf7 VK |
1861 | } |
1862 | ||
6019d23a RW |
1863 | if (freq_table[index].frequency == policy->cur) |
1864 | return 0; | |
1865 | ||
1866 | return __target_index(policy, freq_table, index); | |
1da177e4 LT |
1867 | } |
1868 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1869 | ||
1da177e4 LT |
1870 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1871 | unsigned int target_freq, | |
1872 | unsigned int relation) | |
1873 | { | |
f1829e4a | 1874 | int ret = -EINVAL; |
1da177e4 | 1875 | |
ad7722da | 1876 | down_write(&policy->rwsem); |
1da177e4 LT |
1877 | |
1878 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1879 | ||
ad7722da | 1880 | up_write(&policy->rwsem); |
1da177e4 | 1881 | |
1da177e4 LT |
1882 | return ret; |
1883 | } | |
1884 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1885 | ||
de1df26b RW |
1886 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
1887 | { | |
1888 | return NULL; | |
1889 | } | |
1890 | ||
a1317e09 | 1891 | static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event) |
1da177e4 | 1892 | { |
cc993cab | 1893 | int ret; |
6afde10c | 1894 | |
2f0aea93 VK |
1895 | /* Don't start any governor operations if we are entering suspend */ |
1896 | if (cpufreq_suspended) | |
1897 | return 0; | |
cb57720b EZ |
1898 | /* |
1899 | * Governor might not be initiated here if ACPI _PPC changed | |
1900 | * notification happened, so check it. | |
1901 | */ | |
1902 | if (!policy->governor) | |
1903 | return -EINVAL; | |
2f0aea93 | 1904 | |
1c256245 TR |
1905 | if (policy->governor->max_transition_latency && |
1906 | policy->cpuinfo.transition_latency > | |
1907 | policy->governor->max_transition_latency) { | |
de1df26b RW |
1908 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
1909 | ||
1910 | if (gov) { | |
e837f9b5 JP |
1911 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
1912 | policy->governor->name, gov->name); | |
6afde10c | 1913 | policy->governor = gov; |
de1df26b RW |
1914 | } else { |
1915 | return -EINVAL; | |
6afde10c | 1916 | } |
1c256245 | 1917 | } |
1da177e4 | 1918 | |
fe492f3f VK |
1919 | if (event == CPUFREQ_GOV_POLICY_INIT) |
1920 | if (!try_module_get(policy->governor->owner)) | |
1921 | return -EINVAL; | |
1da177e4 | 1922 | |
63431f78 | 1923 | pr_debug("%s: for CPU %u, event %u\n", __func__, policy->cpu, event); |
95731ebb | 1924 | |
1da177e4 LT |
1925 | ret = policy->governor->governor(policy, event); |
1926 | ||
4d5dcc42 VK |
1927 | if (!ret) { |
1928 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
1929 | policy->governor->initialized++; | |
1930 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
1931 | policy->governor->initialized--; | |
1932 | } | |
b394058f | 1933 | |
fe492f3f VK |
1934 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
1935 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
1936 | module_put(policy->governor->owner); |
1937 | ||
1938 | return ret; | |
1939 | } | |
1940 | ||
0a300767 RW |
1941 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
1942 | { | |
1943 | int ret; | |
1944 | ||
3bbf8fe3 RW |
1945 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) |
1946 | cpufreq_update_current_freq(policy); | |
1947 | ||
0a300767 RW |
1948 | ret = cpufreq_governor(policy, CPUFREQ_GOV_START); |
1949 | return ret ? ret : cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1950 | } | |
1951 | ||
1da177e4 LT |
1952 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
1953 | { | |
3bcb09a3 | 1954 | int err; |
1da177e4 LT |
1955 | |
1956 | if (!governor) | |
1957 | return -EINVAL; | |
1958 | ||
a7b422cd KRW |
1959 | if (cpufreq_disabled()) |
1960 | return -ENODEV; | |
1961 | ||
3fc54d37 | 1962 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 1963 | |
b394058f | 1964 | governor->initialized = 0; |
3bcb09a3 | 1965 | err = -EBUSY; |
42f91fa1 | 1966 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
1967 | err = 0; |
1968 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 1969 | } |
1da177e4 | 1970 | |
32ee8c3e | 1971 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 1972 | return err; |
1da177e4 LT |
1973 | } |
1974 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
1975 | ||
1da177e4 LT |
1976 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
1977 | { | |
4573237b VK |
1978 | struct cpufreq_policy *policy; |
1979 | unsigned long flags; | |
90e41bac | 1980 | |
1da177e4 LT |
1981 | if (!governor) |
1982 | return; | |
1983 | ||
a7b422cd KRW |
1984 | if (cpufreq_disabled()) |
1985 | return; | |
1986 | ||
4573237b VK |
1987 | /* clear last_governor for all inactive policies */ |
1988 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1989 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
1990 | if (!strcmp(policy->last_governor, governor->name)) { |
1991 | policy->governor = NULL; | |
4573237b | 1992 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 1993 | } |
90e41bac | 1994 | } |
4573237b | 1995 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 1996 | |
3fc54d37 | 1997 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 1998 | list_del(&governor->governor_list); |
3fc54d37 | 1999 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2000 | return; |
2001 | } | |
2002 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2003 | ||
2004 | ||
1da177e4 LT |
2005 | /********************************************************************* |
2006 | * POLICY INTERFACE * | |
2007 | *********************************************************************/ | |
2008 | ||
2009 | /** | |
2010 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2011 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2012 | * is written | |
1da177e4 LT |
2013 | * |
2014 | * Reads the current cpufreq policy. | |
2015 | */ | |
2016 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2017 | { | |
2018 | struct cpufreq_policy *cpu_policy; | |
2019 | if (!policy) | |
2020 | return -EINVAL; | |
2021 | ||
2022 | cpu_policy = cpufreq_cpu_get(cpu); | |
2023 | if (!cpu_policy) | |
2024 | return -EINVAL; | |
2025 | ||
d5b73cd8 | 2026 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2027 | |
2028 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2029 | return 0; |
2030 | } | |
2031 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2032 | ||
153d7f3f | 2033 | /* |
037ce839 VK |
2034 | * policy : current policy. |
2035 | * new_policy: policy to be set. | |
153d7f3f | 2036 | */ |
037ce839 | 2037 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2038 | struct cpufreq_policy *new_policy) |
1da177e4 | 2039 | { |
d9a789c7 RW |
2040 | struct cpufreq_governor *old_gov; |
2041 | int ret; | |
1da177e4 | 2042 | |
e837f9b5 JP |
2043 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2044 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2045 | |
d5b73cd8 | 2046 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2047 | |
fba9573b PX |
2048 | /* |
2049 | * This check works well when we store new min/max freq attributes, | |
2050 | * because new_policy is a copy of policy with one field updated. | |
2051 | */ | |
2052 | if (new_policy->min > new_policy->max) | |
d9a789c7 | 2053 | return -EINVAL; |
9c9a43ed | 2054 | |
1da177e4 | 2055 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2056 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2057 | if (ret) |
d9a789c7 | 2058 | return ret; |
1da177e4 | 2059 | |
1da177e4 | 2060 | /* adjust if necessary - all reasons */ |
e041c683 | 2061 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2062 | CPUFREQ_ADJUST, new_policy); |
1da177e4 | 2063 | |
bb176f7d VK |
2064 | /* |
2065 | * verify the cpu speed can be set within this limit, which might be | |
2066 | * different to the first one | |
2067 | */ | |
3a3e9e06 | 2068 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2069 | if (ret) |
d9a789c7 | 2070 | return ret; |
1da177e4 LT |
2071 | |
2072 | /* notification of the new policy */ | |
e041c683 | 2073 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2074 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2075 | |
3a3e9e06 VK |
2076 | policy->min = new_policy->min; |
2077 | policy->max = new_policy->max; | |
1da177e4 | 2078 | |
2d06d8c4 | 2079 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2080 | policy->min, policy->max); |
1da177e4 | 2081 | |
1c3d85dd | 2082 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2083 | policy->policy = new_policy->policy; |
2d06d8c4 | 2084 | pr_debug("setting range\n"); |
d9a789c7 RW |
2085 | return cpufreq_driver->setpolicy(new_policy); |
2086 | } | |
1da177e4 | 2087 | |
0a300767 RW |
2088 | if (new_policy->governor == policy->governor) { |
2089 | pr_debug("cpufreq: governor limits update\n"); | |
2090 | return cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2091 | } | |
7bd353a9 | 2092 | |
d9a789c7 RW |
2093 | pr_debug("governor switch\n"); |
2094 | ||
2095 | /* save old, working values */ | |
2096 | old_gov = policy->governor; | |
2097 | /* end old governor */ | |
2098 | if (old_gov) { | |
a1317e09 | 2099 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
4bc384ae VK |
2100 | if (ret) { |
2101 | /* This can happen due to race with other operations */ | |
2102 | pr_debug("%s: Failed to Stop Governor: %s (%d)\n", | |
2103 | __func__, old_gov->name, ret); | |
2104 | return ret; | |
2105 | } | |
2106 | ||
a1317e09 | 2107 | ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
4bc384ae VK |
2108 | if (ret) { |
2109 | pr_err("%s: Failed to Exit Governor: %s (%d)\n", | |
2110 | __func__, old_gov->name, ret); | |
2111 | return ret; | |
2112 | } | |
1da177e4 LT |
2113 | } |
2114 | ||
d9a789c7 RW |
2115 | /* start new governor */ |
2116 | policy->governor = new_policy->governor; | |
a1317e09 | 2117 | ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); |
4bc384ae | 2118 | if (!ret) { |
0a300767 RW |
2119 | ret = cpufreq_start_governor(policy); |
2120 | if (!ret) { | |
2121 | pr_debug("cpufreq: governor change\n"); | |
2122 | return 0; | |
2123 | } | |
a1317e09 | 2124 | cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
d9a789c7 RW |
2125 | } |
2126 | ||
2127 | /* new governor failed, so re-start old one */ | |
2128 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2129 | if (old_gov) { | |
2130 | policy->governor = old_gov; | |
a1317e09 | 2131 | if (cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) |
4bc384ae VK |
2132 | policy->governor = NULL; |
2133 | else | |
0a300767 | 2134 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2135 | } |
2136 | ||
4bc384ae | 2137 | return ret; |
1da177e4 LT |
2138 | } |
2139 | ||
1da177e4 LT |
2140 | /** |
2141 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2142 | * @cpu: CPU which shall be re-evaluated | |
2143 | * | |
25985edc | 2144 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2145 | * at different times. |
2146 | */ | |
2147 | int cpufreq_update_policy(unsigned int cpu) | |
2148 | { | |
3a3e9e06 VK |
2149 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2150 | struct cpufreq_policy new_policy; | |
f1829e4a | 2151 | int ret; |
1da177e4 | 2152 | |
fefa8ff8 AP |
2153 | if (!policy) |
2154 | return -ENODEV; | |
1da177e4 | 2155 | |
ad7722da | 2156 | down_write(&policy->rwsem); |
1da177e4 | 2157 | |
2d06d8c4 | 2158 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2159 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2160 | new_policy.min = policy->user_policy.min; |
2161 | new_policy.max = policy->user_policy.max; | |
1da177e4 | 2162 | |
bb176f7d VK |
2163 | /* |
2164 | * BIOS might change freq behind our back | |
2165 | * -> ask driver for current freq and notify governors about a change | |
2166 | */ | |
2ed99e39 | 2167 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
999f5729 | 2168 | new_policy.cur = cpufreq_update_current_freq(policy); |
bd0fa9bb VK |
2169 | if (WARN_ON(!new_policy.cur)) { |
2170 | ret = -EIO; | |
fefa8ff8 | 2171 | goto unlock; |
bd0fa9bb | 2172 | } |
0961dd0d TR |
2173 | } |
2174 | ||
037ce839 | 2175 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2176 | |
fefa8ff8 | 2177 | unlock: |
ad7722da | 2178 | up_write(&policy->rwsem); |
5a01f2e8 | 2179 | |
3a3e9e06 | 2180 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2181 | return ret; |
2182 | } | |
2183 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2184 | ||
2760984f | 2185 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2186 | unsigned long action, void *hcpu) |
2187 | { | |
2188 | unsigned int cpu = (unsigned long)hcpu; | |
c32b6b8e | 2189 | |
0b275352 RW |
2190 | switch (action & ~CPU_TASKS_FROZEN) { |
2191 | case CPU_ONLINE: | |
2192 | cpufreq_online(cpu); | |
2193 | break; | |
5302c3fb | 2194 | |
0b275352 | 2195 | case CPU_DOWN_PREPARE: |
69cee714 | 2196 | cpufreq_offline(cpu); |
0b275352 | 2197 | break; |
5302c3fb | 2198 | |
0b275352 RW |
2199 | case CPU_DOWN_FAILED: |
2200 | cpufreq_online(cpu); | |
2201 | break; | |
c32b6b8e AR |
2202 | } |
2203 | return NOTIFY_OK; | |
2204 | } | |
2205 | ||
9c36f746 | 2206 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2207 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2208 | }; |
1da177e4 | 2209 | |
6f19efc0 LM |
2210 | /********************************************************************* |
2211 | * BOOST * | |
2212 | *********************************************************************/ | |
2213 | static int cpufreq_boost_set_sw(int state) | |
2214 | { | |
2215 | struct cpufreq_frequency_table *freq_table; | |
2216 | struct cpufreq_policy *policy; | |
2217 | int ret = -EINVAL; | |
2218 | ||
f963735a | 2219 | for_each_active_policy(policy) { |
6f19efc0 LM |
2220 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2221 | if (freq_table) { | |
2222 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2223 | freq_table); | |
2224 | if (ret) { | |
2225 | pr_err("%s: Policy frequency update failed\n", | |
2226 | __func__); | |
2227 | break; | |
2228 | } | |
49f18560 VK |
2229 | |
2230 | down_write(&policy->rwsem); | |
6f19efc0 | 2231 | policy->user_policy.max = policy->max; |
a1317e09 | 2232 | cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
49f18560 | 2233 | up_write(&policy->rwsem); |
6f19efc0 LM |
2234 | } |
2235 | } | |
2236 | ||
2237 | return ret; | |
2238 | } | |
2239 | ||
2240 | int cpufreq_boost_trigger_state(int state) | |
2241 | { | |
2242 | unsigned long flags; | |
2243 | int ret = 0; | |
2244 | ||
2245 | if (cpufreq_driver->boost_enabled == state) | |
2246 | return 0; | |
2247 | ||
2248 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2249 | cpufreq_driver->boost_enabled = state; | |
2250 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2251 | ||
2252 | ret = cpufreq_driver->set_boost(state); | |
2253 | if (ret) { | |
2254 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2255 | cpufreq_driver->boost_enabled = !state; | |
2256 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2257 | ||
e837f9b5 JP |
2258 | pr_err("%s: Cannot %s BOOST\n", |
2259 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2260 | } |
2261 | ||
2262 | return ret; | |
2263 | } | |
2264 | ||
41669da0 | 2265 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2266 | { |
7a6c79f2 | 2267 | return likely(cpufreq_driver) && cpufreq_driver->set_boost; |
6f19efc0 | 2268 | } |
6f19efc0 | 2269 | |
44139ed4 VK |
2270 | static int create_boost_sysfs_file(void) |
2271 | { | |
2272 | int ret; | |
2273 | ||
c82bd444 | 2274 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2275 | if (ret) |
2276 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2277 | __func__); | |
2278 | ||
2279 | return ret; | |
2280 | } | |
2281 | ||
2282 | static void remove_boost_sysfs_file(void) | |
2283 | { | |
2284 | if (cpufreq_boost_supported()) | |
c82bd444 | 2285 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2286 | } |
2287 | ||
2288 | int cpufreq_enable_boost_support(void) | |
2289 | { | |
2290 | if (!cpufreq_driver) | |
2291 | return -EINVAL; | |
2292 | ||
2293 | if (cpufreq_boost_supported()) | |
2294 | return 0; | |
2295 | ||
7a6c79f2 | 2296 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2297 | |
2298 | /* This will get removed on driver unregister */ | |
2299 | return create_boost_sysfs_file(); | |
2300 | } | |
2301 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2302 | ||
6f19efc0 LM |
2303 | int cpufreq_boost_enabled(void) |
2304 | { | |
2305 | return cpufreq_driver->boost_enabled; | |
2306 | } | |
2307 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2308 | ||
1da177e4 LT |
2309 | /********************************************************************* |
2310 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2311 | *********************************************************************/ | |
2312 | ||
2313 | /** | |
2314 | * cpufreq_register_driver - register a CPU Frequency driver | |
2315 | * @driver_data: A struct cpufreq_driver containing the values# | |
2316 | * submitted by the CPU Frequency driver. | |
2317 | * | |
bb176f7d | 2318 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2319 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2320 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2321 | * |
2322 | */ | |
221dee28 | 2323 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2324 | { |
2325 | unsigned long flags; | |
2326 | int ret; | |
2327 | ||
a7b422cd KRW |
2328 | if (cpufreq_disabled()) |
2329 | return -ENODEV; | |
2330 | ||
1da177e4 | 2331 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2332 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2333 | driver_data->target) || |
2334 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2335 | driver_data->target)) || |
2336 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2337 | return -EINVAL; |
2338 | ||
2d06d8c4 | 2339 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2340 | |
fdd320da RW |
2341 | /* Protect against concurrent CPU online/offline. */ |
2342 | get_online_cpus(); | |
2343 | ||
0d1857a1 | 2344 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2345 | if (cpufreq_driver) { |
0d1857a1 | 2346 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2347 | ret = -EEXIST; |
2348 | goto out; | |
1da177e4 | 2349 | } |
1c3d85dd | 2350 | cpufreq_driver = driver_data; |
0d1857a1 | 2351 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2352 | |
bc68b7df VK |
2353 | if (driver_data->setpolicy) |
2354 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2355 | ||
7a6c79f2 RW |
2356 | if (cpufreq_boost_supported()) { |
2357 | ret = create_boost_sysfs_file(); | |
2358 | if (ret) | |
2359 | goto err_null_driver; | |
2360 | } | |
6f19efc0 | 2361 | |
8a25a2fd | 2362 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2363 | if (ret) |
6f19efc0 | 2364 | goto err_boost_unreg; |
1da177e4 | 2365 | |
ce1bcfe9 VK |
2366 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2367 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2368 | /* if all ->init() calls failed, unregister */ |
ce1bcfe9 VK |
2369 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2370 | driver_data->name); | |
2371 | goto err_if_unreg; | |
1da177e4 LT |
2372 | } |
2373 | ||
8f5bc2ab | 2374 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2375 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2376 | |
fdd320da RW |
2377 | out: |
2378 | put_online_cpus(); | |
2379 | return ret; | |
2380 | ||
8a25a2fd KS |
2381 | err_if_unreg: |
2382 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2383 | err_boost_unreg: |
44139ed4 | 2384 | remove_boost_sysfs_file(); |
8f5bc2ab | 2385 | err_null_driver: |
0d1857a1 | 2386 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2387 | cpufreq_driver = NULL; |
0d1857a1 | 2388 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da | 2389 | goto out; |
1da177e4 LT |
2390 | } |
2391 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2392 | ||
1da177e4 LT |
2393 | /** |
2394 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2395 | * | |
bb176f7d | 2396 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2397 | * the right to do so, i.e. if you have succeeded in initialising before! |
2398 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2399 | * currently not initialised. | |
2400 | */ | |
221dee28 | 2401 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2402 | { |
2403 | unsigned long flags; | |
2404 | ||
1c3d85dd | 2405 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2406 | return -EINVAL; |
1da177e4 | 2407 | |
2d06d8c4 | 2408 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2409 | |
454d3a25 SAS |
2410 | /* Protect against concurrent cpu hotplug */ |
2411 | get_online_cpus(); | |
8a25a2fd | 2412 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2413 | remove_boost_sysfs_file(); |
65edc68c | 2414 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2415 | |
0d1857a1 | 2416 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2417 | |
1c3d85dd | 2418 | cpufreq_driver = NULL; |
6eed9404 | 2419 | |
0d1857a1 | 2420 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
454d3a25 | 2421 | put_online_cpus(); |
1da177e4 LT |
2422 | |
2423 | return 0; | |
2424 | } | |
2425 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2426 | |
90de2a4a DA |
2427 | /* |
2428 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2429 | * or mutexes when secondary CPUs are halted. | |
2430 | */ | |
2431 | static struct syscore_ops cpufreq_syscore_ops = { | |
2432 | .shutdown = cpufreq_suspend, | |
2433 | }; | |
2434 | ||
c82bd444 VK |
2435 | struct kobject *cpufreq_global_kobject; |
2436 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2437 | ||
5a01f2e8 VP |
2438 | static int __init cpufreq_core_init(void) |
2439 | { | |
a7b422cd KRW |
2440 | if (cpufreq_disabled()) |
2441 | return -ENODEV; | |
2442 | ||
8eec1020 | 2443 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2444 | BUG_ON(!cpufreq_global_kobject); |
2445 | ||
90de2a4a DA |
2446 | register_syscore_ops(&cpufreq_syscore_ops); |
2447 | ||
5a01f2e8 VP |
2448 | return 0; |
2449 | } | |
5a01f2e8 | 2450 | core_initcall(cpufreq_core_init); |