Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
2f0aea93 | 29 | #include <linux/suspend.h> |
90de2a4a | 30 | #include <linux/syscore_ops.h> |
5ff0a268 | 31 | #include <linux/tick.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
b4f0676f | 34 | static LIST_HEAD(cpufreq_policy_list); |
f963735a VK |
35 | |
36 | static inline bool policy_is_inactive(struct cpufreq_policy *policy) | |
37 | { | |
38 | return cpumask_empty(policy->cpus); | |
39 | } | |
40 | ||
41 | static bool suitable_policy(struct cpufreq_policy *policy, bool active) | |
42 | { | |
43 | return active == !policy_is_inactive(policy); | |
44 | } | |
45 | ||
46 | /* Finds Next Acive/Inactive policy */ | |
47 | static struct cpufreq_policy *next_policy(struct cpufreq_policy *policy, | |
48 | bool active) | |
49 | { | |
50 | do { | |
51 | policy = list_next_entry(policy, policy_list); | |
52 | ||
53 | /* No more policies in the list */ | |
54 | if (&policy->policy_list == &cpufreq_policy_list) | |
55 | return NULL; | |
56 | } while (!suitable_policy(policy, active)); | |
57 | ||
58 | return policy; | |
59 | } | |
60 | ||
61 | static struct cpufreq_policy *first_policy(bool active) | |
62 | { | |
63 | struct cpufreq_policy *policy; | |
64 | ||
65 | /* No policies in the list */ | |
66 | if (list_empty(&cpufreq_policy_list)) | |
67 | return NULL; | |
68 | ||
69 | policy = list_first_entry(&cpufreq_policy_list, typeof(*policy), | |
70 | policy_list); | |
71 | ||
72 | if (!suitable_policy(policy, active)) | |
73 | policy = next_policy(policy, active); | |
74 | ||
75 | return policy; | |
76 | } | |
77 | ||
78 | /* Macros to iterate over CPU policies */ | |
79 | #define for_each_suitable_policy(__policy, __active) \ | |
80 | for (__policy = first_policy(__active); \ | |
81 | __policy; \ | |
82 | __policy = next_policy(__policy, __active)) | |
83 | ||
84 | #define for_each_active_policy(__policy) \ | |
85 | for_each_suitable_policy(__policy, true) | |
86 | #define for_each_inactive_policy(__policy) \ | |
87 | for_each_suitable_policy(__policy, false) | |
88 | ||
89 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
90 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
91 | ||
f7b27061 VK |
92 | /* Iterate over governors */ |
93 | static LIST_HEAD(cpufreq_governor_list); | |
94 | #define for_each_governor(__governor) \ | |
95 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
96 | ||
1da177e4 | 97 | /** |
cd878479 | 98 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
99 | * level driver of CPUFreq support, and its spinlock. This lock |
100 | * also protects the cpufreq_cpu_data array. | |
101 | */ | |
1c3d85dd | 102 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 103 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 104 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
6f1e4efd | 105 | DEFINE_MUTEX(cpufreq_governor_lock); |
bb176f7d | 106 | |
2f0aea93 VK |
107 | /* Flag to suspend/resume CPUFreq governors */ |
108 | static bool cpufreq_suspended; | |
1da177e4 | 109 | |
9c0ebcf7 VK |
110 | static inline bool has_target(void) |
111 | { | |
112 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
113 | } | |
114 | ||
1da177e4 | 115 | /* internal prototypes */ |
29464f28 DJ |
116 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
117 | unsigned int event); | |
d92d50a4 | 118 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
65f27f38 | 119 | static void handle_update(struct work_struct *work); |
1da177e4 LT |
120 | |
121 | /** | |
32ee8c3e DJ |
122 | * Two notifier lists: the "policy" list is involved in the |
123 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
124 | * "transition" list for kernel code that needs to handle |
125 | * changes to devices when the CPU clock speed changes. | |
126 | * The mutex locks both lists. | |
127 | */ | |
e041c683 | 128 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 129 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 130 | |
74212ca4 | 131 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
132 | static int __init init_cpufreq_transition_notifier_list(void) |
133 | { | |
134 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 135 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
136 | return 0; |
137 | } | |
b3438f82 | 138 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 139 | |
a7b422cd | 140 | static int off __read_mostly; |
da584455 | 141 | static int cpufreq_disabled(void) |
a7b422cd KRW |
142 | { |
143 | return off; | |
144 | } | |
145 | void disable_cpufreq(void) | |
146 | { | |
147 | off = 1; | |
148 | } | |
29464f28 | 149 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 150 | |
4d5dcc42 VK |
151 | bool have_governor_per_policy(void) |
152 | { | |
0b981e70 | 153 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 154 | } |
3f869d6d | 155 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 156 | |
944e9a03 VK |
157 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
158 | { | |
159 | if (have_governor_per_policy()) | |
160 | return &policy->kobj; | |
161 | else | |
162 | return cpufreq_global_kobject; | |
163 | } | |
164 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
165 | ||
5a31d594 VK |
166 | struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu) |
167 | { | |
168 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
169 | ||
170 | return policy && !policy_is_inactive(policy) ? | |
171 | policy->freq_table : NULL; | |
172 | } | |
173 | EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table); | |
174 | ||
72a4ce34 VK |
175 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
176 | { | |
177 | u64 idle_time; | |
178 | u64 cur_wall_time; | |
179 | u64 busy_time; | |
180 | ||
181 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
182 | ||
183 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
184 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
185 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
186 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
187 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
188 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
189 | ||
190 | idle_time = cur_wall_time - busy_time; | |
191 | if (wall) | |
192 | *wall = cputime_to_usecs(cur_wall_time); | |
193 | ||
194 | return cputime_to_usecs(idle_time); | |
195 | } | |
196 | ||
197 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
198 | { | |
199 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
200 | ||
201 | if (idle_time == -1ULL) | |
202 | return get_cpu_idle_time_jiffy(cpu, wall); | |
203 | else if (!io_busy) | |
204 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
205 | ||
206 | return idle_time; | |
207 | } | |
208 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
209 | ||
70e9e778 VK |
210 | /* |
211 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
212 | * drivers of SMP systems. It will do following: | |
213 | * - validate & show freq table passed | |
214 | * - set policies transition latency | |
215 | * - policy->cpus with all possible CPUs | |
216 | */ | |
217 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
218 | struct cpufreq_frequency_table *table, | |
219 | unsigned int transition_latency) | |
220 | { | |
221 | int ret; | |
222 | ||
223 | ret = cpufreq_table_validate_and_show(policy, table); | |
224 | if (ret) { | |
225 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
226 | return ret; | |
227 | } | |
228 | ||
229 | policy->cpuinfo.transition_latency = transition_latency; | |
230 | ||
231 | /* | |
58405af6 | 232 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
233 | * share the clock and voltage and clock. |
234 | */ | |
235 | cpumask_setall(policy->cpus); | |
236 | ||
237 | return 0; | |
238 | } | |
239 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
240 | ||
1f0bd44e | 241 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
242 | { |
243 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
244 | ||
988bed09 VK |
245 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
246 | } | |
1f0bd44e | 247 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
248 | |
249 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
250 | { | |
251 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
252 | ||
652ed95d | 253 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
254 | pr_err("%s: No %s associated to cpu: %d\n", |
255 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
256 | return 0; |
257 | } | |
258 | ||
259 | return clk_get_rate(policy->clk) / 1000; | |
260 | } | |
261 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
262 | ||
50e9c852 VK |
263 | /** |
264 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
265 | * | |
266 | * @cpu: cpu to find policy for. | |
267 | * | |
268 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
269 | * It also increments the kobject reference count to mark it busy and so would | |
270 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
271 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
272 | * freed as that depends on the kobj count. | |
273 | * | |
50e9c852 VK |
274 | * Return: A valid policy on success, otherwise NULL on failure. |
275 | */ | |
6eed9404 | 276 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 277 | { |
6eed9404 | 278 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
279 | unsigned long flags; |
280 | ||
1b947c90 | 281 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
282 | return NULL; |
283 | ||
1da177e4 | 284 | /* get the cpufreq driver */ |
1c3d85dd | 285 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 286 | |
6eed9404 VK |
287 | if (cpufreq_driver) { |
288 | /* get the CPU */ | |
988bed09 | 289 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
290 | if (policy) |
291 | kobject_get(&policy->kobj); | |
292 | } | |
1da177e4 | 293 | |
6eed9404 | 294 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 295 | |
3a3e9e06 | 296 | return policy; |
a9144436 | 297 | } |
1da177e4 LT |
298 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
299 | ||
50e9c852 VK |
300 | /** |
301 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
302 | * | |
303 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
304 | * | |
305 | * This decrements the kobject reference count incremented earlier by calling | |
306 | * cpufreq_cpu_get(). | |
50e9c852 | 307 | */ |
3a3e9e06 | 308 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 309 | { |
6eed9404 | 310 | kobject_put(&policy->kobj); |
1da177e4 LT |
311 | } |
312 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
313 | ||
1da177e4 LT |
314 | /********************************************************************* |
315 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
316 | *********************************************************************/ | |
317 | ||
318 | /** | |
319 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
320 | * | |
321 | * This function alters the system "loops_per_jiffy" for the clock | |
322 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 323 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
324 | * per-CPU loops_per_jiffy value wherever possible. |
325 | */ | |
858119e1 | 326 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 327 | { |
39c132ee VK |
328 | #ifndef CONFIG_SMP |
329 | static unsigned long l_p_j_ref; | |
330 | static unsigned int l_p_j_ref_freq; | |
331 | ||
1da177e4 LT |
332 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
333 | return; | |
334 | ||
335 | if (!l_p_j_ref_freq) { | |
336 | l_p_j_ref = loops_per_jiffy; | |
337 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
338 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
339 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 340 | } |
0b443ead | 341 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
342 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
343 | ci->new); | |
e837f9b5 JP |
344 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
345 | loops_per_jiffy, ci->new); | |
1da177e4 | 346 | } |
1da177e4 | 347 | #endif |
39c132ee | 348 | } |
1da177e4 | 349 | |
0956df9c | 350 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 351 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
352 | { |
353 | BUG_ON(irqs_disabled()); | |
354 | ||
d5aaffa9 DB |
355 | if (cpufreq_disabled()) |
356 | return; | |
357 | ||
1c3d85dd | 358 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 359 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 360 | state, freqs->new); |
1da177e4 | 361 | |
1da177e4 | 362 | switch (state) { |
e4472cb3 | 363 | |
1da177e4 | 364 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 365 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
366 | * which is not equal to what the cpufreq core thinks is |
367 | * "old frequency". | |
1da177e4 | 368 | */ |
1c3d85dd | 369 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
370 | if ((policy) && (policy->cpu == freqs->cpu) && |
371 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
372 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
373 | freqs->old, policy->cur); | |
e4472cb3 | 374 | freqs->old = policy->cur; |
1da177e4 LT |
375 | } |
376 | } | |
b4dfdbb3 | 377 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 378 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
379 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
380 | break; | |
e4472cb3 | 381 | |
1da177e4 LT |
382 | case CPUFREQ_POSTCHANGE: |
383 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
384 | pr_debug("FREQ: %lu - CPU: %lu\n", |
385 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 386 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 387 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 388 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
389 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
390 | policy->cur = freqs->new; | |
1da177e4 LT |
391 | break; |
392 | } | |
1da177e4 | 393 | } |
bb176f7d | 394 | |
b43a7ffb VK |
395 | /** |
396 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
397 | * on frequency transition. | |
398 | * | |
399 | * This function calls the transition notifiers and the "adjust_jiffies" | |
400 | * function. It is called twice on all CPU frequency changes that have | |
401 | * external effects. | |
402 | */ | |
236a9800 | 403 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
404 | struct cpufreq_freqs *freqs, unsigned int state) |
405 | { | |
406 | for_each_cpu(freqs->cpu, policy->cpus) | |
407 | __cpufreq_notify_transition(policy, freqs, state); | |
408 | } | |
1da177e4 | 409 | |
f7ba3b41 | 410 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 411 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
412 | struct cpufreq_freqs *freqs, int transition_failed) |
413 | { | |
414 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
415 | if (!transition_failed) | |
416 | return; | |
417 | ||
418 | swap(freqs->old, freqs->new); | |
419 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
420 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
421 | } | |
f7ba3b41 | 422 | |
12478cf0 SB |
423 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
424 | struct cpufreq_freqs *freqs) | |
425 | { | |
ca654dc3 SB |
426 | |
427 | /* | |
428 | * Catch double invocations of _begin() which lead to self-deadlock. | |
429 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
430 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
431 | * double invocations are very low. Moreover, there are scenarios | |
432 | * where these checks can emit false-positive warnings in these | |
433 | * drivers; so we avoid that by skipping them altogether. | |
434 | */ | |
435 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
436 | && current == policy->transition_task); | |
437 | ||
12478cf0 SB |
438 | wait: |
439 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
440 | ||
441 | spin_lock(&policy->transition_lock); | |
442 | ||
443 | if (unlikely(policy->transition_ongoing)) { | |
444 | spin_unlock(&policy->transition_lock); | |
445 | goto wait; | |
446 | } | |
447 | ||
448 | policy->transition_ongoing = true; | |
ca654dc3 | 449 | policy->transition_task = current; |
12478cf0 SB |
450 | |
451 | spin_unlock(&policy->transition_lock); | |
452 | ||
453 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
454 | } | |
455 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
456 | ||
457 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
458 | struct cpufreq_freqs *freqs, int transition_failed) | |
459 | { | |
460 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
461 | return; | |
462 | ||
463 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
464 | ||
465 | policy->transition_ongoing = false; | |
ca654dc3 | 466 | policy->transition_task = NULL; |
12478cf0 SB |
467 | |
468 | wake_up(&policy->transition_wait); | |
469 | } | |
470 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
471 | ||
1da177e4 | 472 | |
1da177e4 LT |
473 | /********************************************************************* |
474 | * SYSFS INTERFACE * | |
475 | *********************************************************************/ | |
8a5c74a1 | 476 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
477 | struct attribute *attr, char *buf) |
478 | { | |
479 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
480 | } | |
481 | ||
482 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
483 | const char *buf, size_t count) | |
484 | { | |
485 | int ret, enable; | |
486 | ||
487 | ret = sscanf(buf, "%d", &enable); | |
488 | if (ret != 1 || enable < 0 || enable > 1) | |
489 | return -EINVAL; | |
490 | ||
491 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
492 | pr_err("%s: Cannot %s BOOST!\n", |
493 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
494 | return -EINVAL; |
495 | } | |
496 | ||
e837f9b5 JP |
497 | pr_debug("%s: cpufreq BOOST %s\n", |
498 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
499 | |
500 | return count; | |
501 | } | |
502 | define_one_global_rw(boost); | |
1da177e4 | 503 | |
42f91fa1 | 504 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
505 | { |
506 | struct cpufreq_governor *t; | |
507 | ||
f7b27061 | 508 | for_each_governor(t) |
7c4f4539 | 509 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
510 | return t; |
511 | ||
512 | return NULL; | |
513 | } | |
514 | ||
1da177e4 LT |
515 | /** |
516 | * cpufreq_parse_governor - parse a governor string | |
517 | */ | |
905d77cd | 518 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
519 | struct cpufreq_governor **governor) |
520 | { | |
3bcb09a3 | 521 | int err = -EINVAL; |
1c3d85dd | 522 | |
1c3d85dd | 523 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 524 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 525 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 526 | err = 0; |
7c4f4539 | 527 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 528 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 529 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 530 | err = 0; |
1da177e4 | 531 | } |
2e1cc3a5 | 532 | } else { |
1da177e4 | 533 | struct cpufreq_governor *t; |
3bcb09a3 | 534 | |
3fc54d37 | 535 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 536 | |
42f91fa1 | 537 | t = find_governor(str_governor); |
3bcb09a3 | 538 | |
ea714970 | 539 | if (t == NULL) { |
1a8e1463 | 540 | int ret; |
ea714970 | 541 | |
1a8e1463 KC |
542 | mutex_unlock(&cpufreq_governor_mutex); |
543 | ret = request_module("cpufreq_%s", str_governor); | |
544 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 545 | |
1a8e1463 | 546 | if (ret == 0) |
42f91fa1 | 547 | t = find_governor(str_governor); |
ea714970 JF |
548 | } |
549 | ||
3bcb09a3 JF |
550 | if (t != NULL) { |
551 | *governor = t; | |
552 | err = 0; | |
1da177e4 | 553 | } |
3bcb09a3 | 554 | |
3fc54d37 | 555 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 556 | } |
3bcb09a3 | 557 | return err; |
1da177e4 | 558 | } |
1da177e4 | 559 | |
1da177e4 | 560 | /** |
e08f5f5b GS |
561 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
562 | * print out cpufreq information | |
1da177e4 LT |
563 | * |
564 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
565 | * "unsigned int". | |
566 | */ | |
567 | ||
32ee8c3e DJ |
568 | #define show_one(file_name, object) \ |
569 | static ssize_t show_##file_name \ | |
905d77cd | 570 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 571 | { \ |
29464f28 | 572 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
573 | } |
574 | ||
575 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
576 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 577 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
578 | show_one(scaling_min_freq, min); |
579 | show_one(scaling_max_freq, max); | |
c034b02e | 580 | |
09347b29 | 581 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
582 | { |
583 | ssize_t ret; | |
584 | ||
585 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
586 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
587 | else | |
588 | ret = sprintf(buf, "%u\n", policy->cur); | |
589 | return ret; | |
590 | } | |
1da177e4 | 591 | |
037ce839 | 592 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 593 | struct cpufreq_policy *new_policy); |
7970e08b | 594 | |
1da177e4 LT |
595 | /** |
596 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
597 | */ | |
598 | #define store_one(file_name, object) \ | |
599 | static ssize_t store_##file_name \ | |
905d77cd | 600 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 601 | { \ |
619c144c | 602 | int ret, temp; \ |
1da177e4 LT |
603 | struct cpufreq_policy new_policy; \ |
604 | \ | |
8fa5b631 | 605 | memcpy(&new_policy, policy, sizeof(*policy)); \ |
1da177e4 | 606 | \ |
29464f28 | 607 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
608 | if (ret != 1) \ |
609 | return -EINVAL; \ | |
610 | \ | |
619c144c | 611 | temp = new_policy.object; \ |
037ce839 | 612 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
613 | if (!ret) \ |
614 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
615 | \ |
616 | return ret ? ret : count; \ | |
617 | } | |
618 | ||
29464f28 DJ |
619 | store_one(scaling_min_freq, min); |
620 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
621 | |
622 | /** | |
623 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
624 | */ | |
905d77cd DJ |
625 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
626 | char *buf) | |
1da177e4 | 627 | { |
d92d50a4 | 628 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
629 | if (!cur_freq) |
630 | return sprintf(buf, "<unknown>"); | |
631 | return sprintf(buf, "%u\n", cur_freq); | |
632 | } | |
633 | ||
1da177e4 LT |
634 | /** |
635 | * show_scaling_governor - show the current policy for the specified CPU | |
636 | */ | |
905d77cd | 637 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 638 | { |
29464f28 | 639 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
640 | return sprintf(buf, "powersave\n"); |
641 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
642 | return sprintf(buf, "performance\n"); | |
643 | else if (policy->governor) | |
4b972f0b | 644 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 645 | policy->governor->name); |
1da177e4 LT |
646 | return -EINVAL; |
647 | } | |
648 | ||
1da177e4 LT |
649 | /** |
650 | * store_scaling_governor - store policy for the specified CPU | |
651 | */ | |
905d77cd DJ |
652 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
653 | const char *buf, size_t count) | |
1da177e4 | 654 | { |
5136fa56 | 655 | int ret; |
1da177e4 LT |
656 | char str_governor[16]; |
657 | struct cpufreq_policy new_policy; | |
658 | ||
8fa5b631 | 659 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 660 | |
29464f28 | 661 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
662 | if (ret != 1) |
663 | return -EINVAL; | |
664 | ||
e08f5f5b GS |
665 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
666 | &new_policy.governor)) | |
1da177e4 LT |
667 | return -EINVAL; |
668 | ||
037ce839 | 669 | ret = cpufreq_set_policy(policy, &new_policy); |
88dc4384 | 670 | return ret ? ret : count; |
1da177e4 LT |
671 | } |
672 | ||
673 | /** | |
674 | * show_scaling_driver - show the cpufreq driver currently loaded | |
675 | */ | |
905d77cd | 676 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 677 | { |
1c3d85dd | 678 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
679 | } |
680 | ||
681 | /** | |
682 | * show_scaling_available_governors - show the available CPUfreq governors | |
683 | */ | |
905d77cd DJ |
684 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
685 | char *buf) | |
1da177e4 LT |
686 | { |
687 | ssize_t i = 0; | |
688 | struct cpufreq_governor *t; | |
689 | ||
9c0ebcf7 | 690 | if (!has_target()) { |
1da177e4 LT |
691 | i += sprintf(buf, "performance powersave"); |
692 | goto out; | |
693 | } | |
694 | ||
f7b27061 | 695 | for_each_governor(t) { |
29464f28 DJ |
696 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
697 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 698 | goto out; |
4b972f0b | 699 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 700 | } |
7d5e350f | 701 | out: |
1da177e4 LT |
702 | i += sprintf(&buf[i], "\n"); |
703 | return i; | |
704 | } | |
e8628dd0 | 705 | |
f4fd3797 | 706 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
707 | { |
708 | ssize_t i = 0; | |
709 | unsigned int cpu; | |
710 | ||
835481d9 | 711 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
712 | if (i) |
713 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
714 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
715 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 716 | break; |
1da177e4 LT |
717 | } |
718 | i += sprintf(&buf[i], "\n"); | |
719 | return i; | |
720 | } | |
f4fd3797 | 721 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 722 | |
e8628dd0 DW |
723 | /** |
724 | * show_related_cpus - show the CPUs affected by each transition even if | |
725 | * hw coordination is in use | |
726 | */ | |
727 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
728 | { | |
f4fd3797 | 729 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
730 | } |
731 | ||
732 | /** | |
733 | * show_affected_cpus - show the CPUs affected by each transition | |
734 | */ | |
735 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
736 | { | |
f4fd3797 | 737 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
738 | } |
739 | ||
9e76988e | 740 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 741 | const char *buf, size_t count) |
9e76988e VP |
742 | { |
743 | unsigned int freq = 0; | |
744 | unsigned int ret; | |
745 | ||
879000f9 | 746 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
747 | return -EINVAL; |
748 | ||
749 | ret = sscanf(buf, "%u", &freq); | |
750 | if (ret != 1) | |
751 | return -EINVAL; | |
752 | ||
753 | policy->governor->store_setspeed(policy, freq); | |
754 | ||
755 | return count; | |
756 | } | |
757 | ||
758 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
759 | { | |
879000f9 | 760 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
761 | return sprintf(buf, "<unsupported>\n"); |
762 | ||
763 | return policy->governor->show_setspeed(policy, buf); | |
764 | } | |
1da177e4 | 765 | |
e2f74f35 | 766 | /** |
8bf1ac72 | 767 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
768 | */ |
769 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
770 | { | |
771 | unsigned int limit; | |
772 | int ret; | |
1c3d85dd RW |
773 | if (cpufreq_driver->bios_limit) { |
774 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
775 | if (!ret) |
776 | return sprintf(buf, "%u\n", limit); | |
777 | } | |
778 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
779 | } | |
780 | ||
6dad2a29 BP |
781 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
782 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
783 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
784 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
785 | cpufreq_freq_attr_ro(scaling_available_governors); | |
786 | cpufreq_freq_attr_ro(scaling_driver); | |
787 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
788 | cpufreq_freq_attr_ro(bios_limit); | |
789 | cpufreq_freq_attr_ro(related_cpus); | |
790 | cpufreq_freq_attr_ro(affected_cpus); | |
791 | cpufreq_freq_attr_rw(scaling_min_freq); | |
792 | cpufreq_freq_attr_rw(scaling_max_freq); | |
793 | cpufreq_freq_attr_rw(scaling_governor); | |
794 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 795 | |
905d77cd | 796 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
797 | &cpuinfo_min_freq.attr, |
798 | &cpuinfo_max_freq.attr, | |
ed129784 | 799 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
800 | &scaling_min_freq.attr, |
801 | &scaling_max_freq.attr, | |
802 | &affected_cpus.attr, | |
e8628dd0 | 803 | &related_cpus.attr, |
1da177e4 LT |
804 | &scaling_governor.attr, |
805 | &scaling_driver.attr, | |
806 | &scaling_available_governors.attr, | |
9e76988e | 807 | &scaling_setspeed.attr, |
1da177e4 LT |
808 | NULL |
809 | }; | |
810 | ||
29464f28 DJ |
811 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
812 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 813 | |
29464f28 | 814 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 815 | { |
905d77cd DJ |
816 | struct cpufreq_policy *policy = to_policy(kobj); |
817 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 818 | ssize_t ret; |
6eed9404 | 819 | |
ad7722da | 820 | down_read(&policy->rwsem); |
5a01f2e8 | 821 | |
e08f5f5b GS |
822 | if (fattr->show) |
823 | ret = fattr->show(policy, buf); | |
824 | else | |
825 | ret = -EIO; | |
826 | ||
ad7722da | 827 | up_read(&policy->rwsem); |
1b750e3b | 828 | |
1da177e4 LT |
829 | return ret; |
830 | } | |
831 | ||
905d77cd DJ |
832 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
833 | const char *buf, size_t count) | |
1da177e4 | 834 | { |
905d77cd DJ |
835 | struct cpufreq_policy *policy = to_policy(kobj); |
836 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 837 | ssize_t ret = -EINVAL; |
6eed9404 | 838 | |
4f750c93 SB |
839 | get_online_cpus(); |
840 | ||
841 | if (!cpu_online(policy->cpu)) | |
842 | goto unlock; | |
843 | ||
ad7722da | 844 | down_write(&policy->rwsem); |
5a01f2e8 | 845 | |
e08f5f5b GS |
846 | if (fattr->store) |
847 | ret = fattr->store(policy, buf, count); | |
848 | else | |
849 | ret = -EIO; | |
850 | ||
ad7722da | 851 | up_write(&policy->rwsem); |
4f750c93 SB |
852 | unlock: |
853 | put_online_cpus(); | |
854 | ||
1da177e4 LT |
855 | return ret; |
856 | } | |
857 | ||
905d77cd | 858 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 859 | { |
905d77cd | 860 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 861 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
862 | complete(&policy->kobj_unregister); |
863 | } | |
864 | ||
52cf25d0 | 865 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
866 | .show = show, |
867 | .store = store, | |
868 | }; | |
869 | ||
870 | static struct kobj_type ktype_cpufreq = { | |
871 | .sysfs_ops = &sysfs_ops, | |
872 | .default_attrs = default_attrs, | |
873 | .release = cpufreq_sysfs_release, | |
874 | }; | |
875 | ||
87549141 VK |
876 | static int add_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) |
877 | { | |
878 | struct device *cpu_dev; | |
879 | ||
880 | pr_debug("%s: Adding symlink for CPU: %u\n", __func__, cpu); | |
881 | ||
882 | if (!policy) | |
883 | return 0; | |
884 | ||
885 | cpu_dev = get_cpu_device(cpu); | |
886 | if (WARN_ON(!cpu_dev)) | |
887 | return 0; | |
888 | ||
889 | return sysfs_create_link(&cpu_dev->kobj, &policy->kobj, "cpufreq"); | |
890 | } | |
891 | ||
892 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) | |
893 | { | |
894 | struct device *cpu_dev; | |
895 | ||
896 | pr_debug("%s: Removing symlink for CPU: %u\n", __func__, cpu); | |
897 | ||
898 | cpu_dev = get_cpu_device(cpu); | |
899 | if (WARN_ON(!cpu_dev)) | |
900 | return; | |
901 | ||
902 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); | |
903 | } | |
904 | ||
905 | /* Add/remove symlinks for all related CPUs */ | |
308b60e7 | 906 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
907 | { |
908 | unsigned int j; | |
909 | int ret = 0; | |
910 | ||
87549141 | 911 | /* Some related CPUs might not be present (physically hotplugged) */ |
559ed407 | 912 | for_each_cpu(j, policy->real_cpus) { |
87549141 | 913 | ret = add_cpu_dev_symlink(policy, j); |
71c3461e RW |
914 | if (ret) |
915 | break; | |
19d6f7ec | 916 | } |
87549141 | 917 | |
19d6f7ec DJ |
918 | return ret; |
919 | } | |
920 | ||
87549141 VK |
921 | static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy) |
922 | { | |
923 | unsigned int j; | |
924 | ||
925 | /* Some related CPUs might not be present (physically hotplugged) */ | |
96bdda61 | 926 | for_each_cpu(j, policy->real_cpus) |
87549141 | 927 | remove_cpu_dev_symlink(policy, j); |
87549141 VK |
928 | } |
929 | ||
d9612a49 | 930 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
931 | { |
932 | struct freq_attr **drv_attr; | |
909a694e | 933 | int ret = 0; |
909a694e | 934 | |
909a694e | 935 | /* set up files for this cpu device */ |
1c3d85dd | 936 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 937 | while (drv_attr && *drv_attr) { |
909a694e DJ |
938 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
939 | if (ret) | |
6d4e81ed | 940 | return ret; |
909a694e DJ |
941 | drv_attr++; |
942 | } | |
1c3d85dd | 943 | if (cpufreq_driver->get) { |
909a694e DJ |
944 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
945 | if (ret) | |
6d4e81ed | 946 | return ret; |
909a694e | 947 | } |
c034b02e DB |
948 | |
949 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
950 | if (ret) | |
6d4e81ed | 951 | return ret; |
c034b02e | 952 | |
1c3d85dd | 953 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
954 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
955 | if (ret) | |
6d4e81ed | 956 | return ret; |
e2f74f35 | 957 | } |
909a694e | 958 | |
6d4e81ed | 959 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
960 | } |
961 | ||
7f0fa40f | 962 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 963 | { |
6e2c89d1 | 964 | struct cpufreq_governor *gov = NULL; |
e18f1682 | 965 | struct cpufreq_policy new_policy; |
e18f1682 | 966 | |
d5b73cd8 | 967 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 968 | |
6e2c89d1 | 969 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 970 | gov = find_governor(policy->last_governor); |
6e2c89d1 | 971 | if (gov) |
972 | pr_debug("Restoring governor %s for cpu %d\n", | |
973 | policy->governor->name, policy->cpu); | |
974 | else | |
975 | gov = CPUFREQ_DEFAULT_GOVERNOR; | |
976 | ||
977 | new_policy.governor = gov; | |
978 | ||
69030dd1 SP |
979 | /* Use the default policy if there is no last_policy. */ |
980 | if (cpufreq_driver->setpolicy) { | |
981 | if (policy->last_policy) | |
982 | new_policy.policy = policy->last_policy; | |
983 | else | |
984 | cpufreq_parse_governor(gov->name, &new_policy.policy, | |
985 | NULL); | |
986 | } | |
ecf7e461 | 987 | /* set default policy */ |
7f0fa40f | 988 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
989 | } |
990 | ||
d9612a49 | 991 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 992 | { |
9c0ebcf7 | 993 | int ret = 0; |
fcf80582 | 994 | |
bb29ae15 VK |
995 | /* Has this CPU been taken care of already? */ |
996 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
997 | return 0; | |
998 | ||
9c0ebcf7 | 999 | if (has_target()) { |
3de9bdeb VK |
1000 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1001 | if (ret) { | |
1002 | pr_err("%s: Failed to stop governor\n", __func__); | |
1003 | return ret; | |
1004 | } | |
1005 | } | |
fcf80582 | 1006 | |
ad7722da | 1007 | down_write(&policy->rwsem); |
fcf80582 | 1008 | cpumask_set_cpu(cpu, policy->cpus); |
ad7722da | 1009 | up_write(&policy->rwsem); |
2eaa3e2d | 1010 | |
9c0ebcf7 | 1011 | if (has_target()) { |
e5c87b76 SK |
1012 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); |
1013 | if (!ret) | |
1014 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1015 | ||
1016 | if (ret) { | |
3de9bdeb VK |
1017 | pr_err("%s: Failed to start governor\n", __func__); |
1018 | return ret; | |
1019 | } | |
820c6ca2 | 1020 | } |
fcf80582 | 1021 | |
87549141 | 1022 | return 0; |
fcf80582 | 1023 | } |
1da177e4 | 1024 | |
a34e63b1 | 1025 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 | 1026 | { |
a34e63b1 | 1027 | struct device *dev = get_cpu_device(cpu); |
e9698cc5 SB |
1028 | struct cpufreq_policy *policy; |
1029 | ||
a34e63b1 RW |
1030 | if (WARN_ON(!dev)) |
1031 | return NULL; | |
1032 | ||
e9698cc5 SB |
1033 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1034 | if (!policy) | |
1035 | return NULL; | |
1036 | ||
1037 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1038 | goto err_free_policy; | |
1039 | ||
1040 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1041 | goto err_free_cpumask; | |
1042 | ||
559ed407 RW |
1043 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1044 | goto err_free_rcpumask; | |
1045 | ||
3510fac4 | 1046 | kobject_init(&policy->kobj, &ktype_cpufreq); |
c88a1f8b | 1047 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1048 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1049 | spin_lock_init(&policy->transition_lock); |
1050 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1051 | init_completion(&policy->kobj_unregister); |
1052 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1053 | |
a34e63b1 | 1054 | policy->cpu = cpu; |
e9698cc5 SB |
1055 | return policy; |
1056 | ||
2fc3384d VK |
1057 | err_free_rcpumask: |
1058 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1059 | err_free_cpumask: |
1060 | free_cpumask_var(policy->cpus); | |
1061 | err_free_policy: | |
1062 | kfree(policy); | |
1063 | ||
1064 | return NULL; | |
1065 | } | |
1066 | ||
2fc3384d | 1067 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify) |
42f921a6 VK |
1068 | { |
1069 | struct kobject *kobj; | |
1070 | struct completion *cmp; | |
1071 | ||
2fc3384d VK |
1072 | if (notify) |
1073 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1074 | CPUFREQ_REMOVE_POLICY, policy); | |
fcd7af91 | 1075 | |
87549141 VK |
1076 | down_write(&policy->rwsem); |
1077 | cpufreq_remove_dev_symlink(policy); | |
42f921a6 VK |
1078 | kobj = &policy->kobj; |
1079 | cmp = &policy->kobj_unregister; | |
87549141 | 1080 | up_write(&policy->rwsem); |
42f921a6 VK |
1081 | kobject_put(kobj); |
1082 | ||
1083 | /* | |
1084 | * We need to make sure that the underlying kobj is | |
1085 | * actually not referenced anymore by anybody before we | |
1086 | * proceed with unloading. | |
1087 | */ | |
1088 | pr_debug("waiting for dropping of refcount\n"); | |
1089 | wait_for_completion(cmp); | |
1090 | pr_debug("wait complete\n"); | |
1091 | } | |
1092 | ||
3654c5cc | 1093 | static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify) |
e9698cc5 | 1094 | { |
988bed09 VK |
1095 | unsigned long flags; |
1096 | int cpu; | |
1097 | ||
1098 | /* Remove policy from list */ | |
1099 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1100 | list_del(&policy->policy_list); | |
1101 | ||
1102 | for_each_cpu(cpu, policy->related_cpus) | |
1103 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1104 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1105 | ||
3654c5cc | 1106 | cpufreq_policy_put_kobj(policy, notify); |
559ed407 | 1107 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1108 | free_cpumask_var(policy->related_cpus); |
1109 | free_cpumask_var(policy->cpus); | |
1110 | kfree(policy); | |
1111 | } | |
1112 | ||
0b275352 | 1113 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1114 | { |
7f0c020a | 1115 | struct cpufreq_policy *policy; |
194d99c7 | 1116 | bool new_policy; |
1da177e4 | 1117 | unsigned long flags; |
0b275352 RW |
1118 | unsigned int j; |
1119 | int ret; | |
87549141 | 1120 | |
0b275352 | 1121 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1122 | |
bb29ae15 | 1123 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1124 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1125 | if (policy) { |
9104bb26 | 1126 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1127 | if (!policy_is_inactive(policy)) |
d9612a49 | 1128 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1129 | |
11ce707e | 1130 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1131 | new_policy = false; |
11ce707e RW |
1132 | down_write(&policy->rwsem); |
1133 | policy->cpu = cpu; | |
1134 | policy->governor = NULL; | |
1135 | up_write(&policy->rwsem); | |
1136 | } else { | |
194d99c7 | 1137 | new_policy = true; |
a34e63b1 | 1138 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1139 | if (!policy) |
d4d854d6 | 1140 | return -ENOMEM; |
72368d12 | 1141 | } |
0d66b91e | 1142 | |
835481d9 | 1143 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1144 | |
1da177e4 LT |
1145 | /* call driver. From then on the cpufreq must be able |
1146 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1147 | */ | |
1c3d85dd | 1148 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1149 | if (ret) { |
2d06d8c4 | 1150 | pr_debug("initialization failed\n"); |
8101f997 | 1151 | goto out_free_policy; |
1da177e4 | 1152 | } |
643ae6e8 | 1153 | |
6d4e81ed TV |
1154 | down_write(&policy->rwsem); |
1155 | ||
194d99c7 | 1156 | if (new_policy) { |
4d1f3a5b | 1157 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1158 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1159 | /* Remember CPUs present at the policy creation time. */ |
559ed407 | 1160 | cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask); |
3510fac4 VK |
1161 | |
1162 | /* Name and add the kobject */ | |
1163 | ret = kobject_add(&policy->kobj, cpufreq_global_kobject, | |
1164 | "policy%u", | |
1165 | cpumask_first(policy->related_cpus)); | |
1166 | if (ret) { | |
1167 | pr_err("%s: failed to add policy->kobj: %d\n", __func__, | |
1168 | ret); | |
1169 | goto out_exit_policy; | |
1170 | } | |
4d1f3a5b | 1171 | } |
559ed407 | 1172 | |
5a7e56a5 VK |
1173 | /* |
1174 | * affected cpus must always be the one, which are online. We aren't | |
1175 | * managing offline cpus here. | |
1176 | */ | |
1177 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1178 | ||
194d99c7 | 1179 | if (new_policy) { |
5a7e56a5 VK |
1180 | policy->user_policy.min = policy->min; |
1181 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1182 | |
988bed09 VK |
1183 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1184 | for_each_cpu(j, policy->related_cpus) | |
1185 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1186 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1187 | } | |
652ed95d | 1188 | |
2ed99e39 | 1189 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1190 | policy->cur = cpufreq_driver->get(policy->cpu); |
1191 | if (!policy->cur) { | |
1192 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1193 | goto out_exit_policy; |
da60ce9f VK |
1194 | } |
1195 | } | |
1196 | ||
d3916691 VK |
1197 | /* |
1198 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1199 | * frequency table present with cpufreq core. In such cases CPU might be | |
1200 | * unstable if it has to run on that frequency for long duration of time | |
1201 | * and so its better to set it to a frequency which is specified in | |
1202 | * freq-table. This also makes cpufreq stats inconsistent as | |
1203 | * cpufreq-stats would fail to register because current frequency of CPU | |
1204 | * isn't found in freq-table. | |
1205 | * | |
1206 | * Because we don't want this change to effect boot process badly, we go | |
1207 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1208 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1209 | * is initialized to zero). | |
1210 | * | |
1211 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1212 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1213 | * equal to target-freq. | |
1214 | */ | |
1215 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1216 | && has_target()) { | |
1217 | /* Are we running at unknown frequency ? */ | |
1218 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1219 | if (ret == -EINVAL) { | |
1220 | /* Warn user and fix it */ | |
1221 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1222 | __func__, policy->cpu, policy->cur); | |
1223 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1224 | CPUFREQ_RELATION_L); | |
1225 | ||
1226 | /* | |
1227 | * Reaching here after boot in a few seconds may not | |
1228 | * mean that system will remain stable at "unknown" | |
1229 | * frequency for longer duration. Hence, a BUG_ON(). | |
1230 | */ | |
1231 | BUG_ON(ret); | |
1232 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1233 | __func__, policy->cpu, policy->cur); | |
1234 | } | |
1235 | } | |
1236 | ||
a1531acd TR |
1237 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1238 | CPUFREQ_START, policy); | |
1239 | ||
194d99c7 | 1240 | if (new_policy) { |
d9612a49 | 1241 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1242 | if (ret) |
8101f997 | 1243 | goto out_exit_policy; |
fcd7af91 VK |
1244 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1245 | CPUFREQ_CREATE_POLICY, policy); | |
8ff69732 | 1246 | |
988bed09 VK |
1247 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1248 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1249 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1250 | } | |
9515f4d6 | 1251 | |
7f0fa40f VK |
1252 | ret = cpufreq_init_policy(policy); |
1253 | if (ret) { | |
1254 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1255 | __func__, cpu, ret); | |
194d99c7 RW |
1256 | /* cpufreq_policy_free() will notify based on this */ |
1257 | new_policy = false; | |
1258 | goto out_exit_policy; | |
08fd8c1c | 1259 | } |
e18f1682 | 1260 | |
4e97b631 | 1261 | up_write(&policy->rwsem); |
08fd8c1c | 1262 | |
038c5b3e | 1263 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1264 | |
7c45cf31 VK |
1265 | /* Callback for handling stuff after policy is ready */ |
1266 | if (cpufreq_driver->ready) | |
1267 | cpufreq_driver->ready(policy); | |
1268 | ||
2d06d8c4 | 1269 | pr_debug("initialization complete\n"); |
87c32271 | 1270 | |
1da177e4 LT |
1271 | return 0; |
1272 | ||
8101f997 | 1273 | out_exit_policy: |
7106e02b PB |
1274 | up_write(&policy->rwsem); |
1275 | ||
da60ce9f VK |
1276 | if (cpufreq_driver->exit) |
1277 | cpufreq_driver->exit(policy); | |
8101f997 | 1278 | out_free_policy: |
194d99c7 | 1279 | cpufreq_policy_free(policy, !new_policy); |
1da177e4 LT |
1280 | return ret; |
1281 | } | |
1282 | ||
0b275352 RW |
1283 | /** |
1284 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1285 | * @dev: CPU device. | |
1286 | * @sif: Subsystem interface structure pointer (not used) | |
1287 | */ | |
1288 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1289 | { | |
1290 | unsigned cpu = dev->id; | |
1291 | int ret; | |
1292 | ||
1293 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1294 | ||
1295 | if (cpu_online(cpu)) { | |
1296 | ret = cpufreq_online(cpu); | |
1297 | } else { | |
1298 | /* | |
1299 | * A hotplug notifier will follow and we will handle it as CPU | |
1300 | * online then. For now, just create the sysfs link, unless | |
1301 | * there is no policy or the link is already present. | |
1302 | */ | |
1303 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
1304 | ||
1305 | ret = policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus) | |
1306 | ? add_cpu_dev_symlink(policy, cpu) : 0; | |
1307 | } | |
6eed9404 | 1308 | |
1da177e4 LT |
1309 | return ret; |
1310 | } | |
1311 | ||
15c0b4d2 | 1312 | static void cpufreq_offline_prepare(unsigned int cpu) |
1da177e4 | 1313 | { |
3a3e9e06 | 1314 | struct cpufreq_policy *policy; |
1da177e4 | 1315 | |
b8eed8af | 1316 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1317 | |
988bed09 | 1318 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1319 | if (!policy) { |
b8eed8af | 1320 | pr_debug("%s: No cpu_data found\n", __func__); |
15c0b4d2 | 1321 | return; |
1da177e4 | 1322 | } |
1da177e4 | 1323 | |
9c0ebcf7 | 1324 | if (has_target()) { |
15c0b4d2 | 1325 | int ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
559ed407 | 1326 | if (ret) |
3de9bdeb | 1327 | pr_err("%s: Failed to stop governor\n", __func__); |
db5f2995 | 1328 | } |
1da177e4 | 1329 | |
4573237b | 1330 | down_write(&policy->rwsem); |
9591becb | 1331 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1332 | |
9591becb VK |
1333 | if (policy_is_inactive(policy)) { |
1334 | if (has_target()) | |
1335 | strncpy(policy->last_governor, policy->governor->name, | |
1336 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1337 | else |
1338 | policy->last_policy = policy->policy; | |
9591becb VK |
1339 | } else if (cpu == policy->cpu) { |
1340 | /* Nominate new CPU */ | |
1341 | policy->cpu = cpumask_any(policy->cpus); | |
1342 | } | |
4573237b | 1343 | up_write(&policy->rwsem); |
084f3493 | 1344 | |
9591becb VK |
1345 | /* Start governor again for active policy */ |
1346 | if (!policy_is_inactive(policy)) { | |
1347 | if (has_target()) { | |
15c0b4d2 | 1348 | int ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); |
9591becb VK |
1349 | if (!ret) |
1350 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1bfb425b | 1351 | |
9591becb VK |
1352 | if (ret) |
1353 | pr_err("%s: Failed to start governor\n", __func__); | |
1354 | } | |
1355 | } else if (cpufreq_driver->stop_cpu) { | |
367dc4aa | 1356 | cpufreq_driver->stop_cpu(policy); |
9591becb | 1357 | } |
cedb70af SB |
1358 | } |
1359 | ||
15c0b4d2 | 1360 | static void cpufreq_offline_finish(unsigned int cpu) |
cedb70af | 1361 | { |
9591becb | 1362 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
cedb70af SB |
1363 | |
1364 | if (!policy) { | |
1365 | pr_debug("%s: No cpu_data found\n", __func__); | |
15c0b4d2 | 1366 | return; |
cedb70af SB |
1367 | } |
1368 | ||
9591becb VK |
1369 | /* Only proceed for inactive policies */ |
1370 | if (!policy_is_inactive(policy)) | |
15c0b4d2 | 1371 | return; |
87549141 VK |
1372 | |
1373 | /* If cpu is last user of policy, free policy */ | |
1374 | if (has_target()) { | |
15c0b4d2 | 1375 | int ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
559ed407 | 1376 | if (ret) |
87549141 | 1377 | pr_err("%s: Failed to exit governor\n", __func__); |
27ecddc2 | 1378 | } |
1da177e4 | 1379 | |
87549141 VK |
1380 | /* |
1381 | * Perform the ->exit() even during light-weight tear-down, | |
1382 | * since this is a core component, and is essential for the | |
1383 | * subsequent light-weight ->init() to succeed. | |
1384 | */ | |
55582bcc | 1385 | if (cpufreq_driver->exit) { |
87549141 | 1386 | cpufreq_driver->exit(policy); |
55582bcc SP |
1387 | policy->freq_table = NULL; |
1388 | } | |
1da177e4 LT |
1389 | } |
1390 | ||
cedb70af | 1391 | /** |
27a862e9 | 1392 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1393 | * |
1394 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1395 | */ |
71db87ba | 1396 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1397 | { |
8a25a2fd | 1398 | unsigned int cpu = dev->id; |
559ed407 | 1399 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1400 | |
559ed407 | 1401 | if (!policy) |
1af115d6 | 1402 | return; |
87549141 | 1403 | |
559ed407 | 1404 | if (cpu_online(cpu)) { |
15c0b4d2 RW |
1405 | cpufreq_offline_prepare(cpu); |
1406 | cpufreq_offline_finish(cpu); | |
559ed407 | 1407 | } |
87549141 | 1408 | |
559ed407 | 1409 | cpumask_clear_cpu(cpu, policy->real_cpus); |
f344dae0 | 1410 | remove_cpu_dev_symlink(policy, cpu); |
87549141 | 1411 | |
f344dae0 | 1412 | if (cpumask_empty(policy->real_cpus)) |
3654c5cc | 1413 | cpufreq_policy_free(policy, true); |
5a01f2e8 VP |
1414 | } |
1415 | ||
65f27f38 | 1416 | static void handle_update(struct work_struct *work) |
1da177e4 | 1417 | { |
65f27f38 DH |
1418 | struct cpufreq_policy *policy = |
1419 | container_of(work, struct cpufreq_policy, update); | |
1420 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1421 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1422 | cpufreq_update_policy(cpu); |
1423 | } | |
1424 | ||
1425 | /** | |
bb176f7d VK |
1426 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1427 | * in deep trouble. | |
a1e1dc41 | 1428 | * @policy: policy managing CPUs |
1da177e4 LT |
1429 | * @new_freq: CPU frequency the CPU actually runs at |
1430 | * | |
29464f28 DJ |
1431 | * We adjust to current frequency first, and need to clean up later. |
1432 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1433 | */ |
a1e1dc41 | 1434 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1435 | unsigned int new_freq) |
1da177e4 LT |
1436 | { |
1437 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1438 | |
e837f9b5 | 1439 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1440 | policy->cur, new_freq); |
1da177e4 | 1441 | |
a1e1dc41 | 1442 | freqs.old = policy->cur; |
1da177e4 | 1443 | freqs.new = new_freq; |
b43a7ffb | 1444 | |
8fec051e VK |
1445 | cpufreq_freq_transition_begin(policy, &freqs); |
1446 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1447 | } |
1448 | ||
32ee8c3e | 1449 | /** |
4ab70df4 | 1450 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1451 | * @cpu: CPU number |
1452 | * | |
1453 | * This is the last known freq, without actually getting it from the driver. | |
1454 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1455 | */ | |
1456 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1457 | { | |
9e21ba8b | 1458 | struct cpufreq_policy *policy; |
e08f5f5b | 1459 | unsigned int ret_freq = 0; |
95235ca2 | 1460 | |
1c3d85dd RW |
1461 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1462 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1463 | |
1464 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1465 | if (policy) { |
e08f5f5b | 1466 | ret_freq = policy->cur; |
95235ca2 VP |
1467 | cpufreq_cpu_put(policy); |
1468 | } | |
1469 | ||
4d34a67d | 1470 | return ret_freq; |
95235ca2 VP |
1471 | } |
1472 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1473 | ||
3d737108 JB |
1474 | /** |
1475 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1476 | * @cpu: CPU number | |
1477 | * | |
1478 | * Just return the max possible frequency for a given CPU. | |
1479 | */ | |
1480 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1481 | { | |
1482 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1483 | unsigned int ret_freq = 0; | |
1484 | ||
1485 | if (policy) { | |
1486 | ret_freq = policy->max; | |
1487 | cpufreq_cpu_put(policy); | |
1488 | } | |
1489 | ||
1490 | return ret_freq; | |
1491 | } | |
1492 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1493 | ||
d92d50a4 | 1494 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1495 | { |
e08f5f5b | 1496 | unsigned int ret_freq = 0; |
5800043b | 1497 | |
1c3d85dd | 1498 | if (!cpufreq_driver->get) |
4d34a67d | 1499 | return ret_freq; |
1da177e4 | 1500 | |
d92d50a4 | 1501 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1502 | |
11e584cf VK |
1503 | /* Updating inactive policies is invalid, so avoid doing that. */ |
1504 | if (unlikely(policy_is_inactive(policy))) | |
1505 | return ret_freq; | |
1506 | ||
e08f5f5b | 1507 | if (ret_freq && policy->cur && |
1c3d85dd | 1508 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1509 | /* verify no discrepancy between actual and |
1510 | saved value exists */ | |
1511 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1512 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1513 | schedule_work(&policy->update); |
1514 | } | |
1515 | } | |
1516 | ||
4d34a67d | 1517 | return ret_freq; |
5a01f2e8 | 1518 | } |
1da177e4 | 1519 | |
5a01f2e8 VP |
1520 | /** |
1521 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1522 | * @cpu: CPU number | |
1523 | * | |
1524 | * Get the CPU current (static) CPU frequency | |
1525 | */ | |
1526 | unsigned int cpufreq_get(unsigned int cpu) | |
1527 | { | |
999976e0 | 1528 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1529 | unsigned int ret_freq = 0; |
5a01f2e8 | 1530 | |
999976e0 AP |
1531 | if (policy) { |
1532 | down_read(&policy->rwsem); | |
d92d50a4 | 1533 | ret_freq = __cpufreq_get(policy); |
999976e0 | 1534 | up_read(&policy->rwsem); |
5a01f2e8 | 1535 | |
999976e0 AP |
1536 | cpufreq_cpu_put(policy); |
1537 | } | |
6eed9404 | 1538 | |
4d34a67d | 1539 | return ret_freq; |
1da177e4 LT |
1540 | } |
1541 | EXPORT_SYMBOL(cpufreq_get); | |
1542 | ||
8a25a2fd KS |
1543 | static struct subsys_interface cpufreq_interface = { |
1544 | .name = "cpufreq", | |
1545 | .subsys = &cpu_subsys, | |
1546 | .add_dev = cpufreq_add_dev, | |
1547 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1548 | }; |
1549 | ||
e28867ea VK |
1550 | /* |
1551 | * In case platform wants some specific frequency to be configured | |
1552 | * during suspend.. | |
1553 | */ | |
1554 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1555 | { | |
1556 | int ret; | |
1557 | ||
1558 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1559 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1560 | return 0; | |
e28867ea VK |
1561 | } |
1562 | ||
1563 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1564 | policy->suspend_freq); | |
1565 | ||
1566 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1567 | CPUFREQ_RELATION_H); | |
1568 | if (ret) | |
1569 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1570 | __func__, policy->suspend_freq, ret); | |
1571 | ||
1572 | return ret; | |
1573 | } | |
1574 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1575 | ||
42d4dc3f | 1576 | /** |
2f0aea93 | 1577 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1578 | * |
2f0aea93 VK |
1579 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1580 | * as some platforms can't change frequency after this point in suspend cycle. | |
1581 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1582 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1583 | */ |
2f0aea93 | 1584 | void cpufreq_suspend(void) |
42d4dc3f | 1585 | { |
3a3e9e06 | 1586 | struct cpufreq_policy *policy; |
42d4dc3f | 1587 | |
2f0aea93 VK |
1588 | if (!cpufreq_driver) |
1589 | return; | |
42d4dc3f | 1590 | |
2f0aea93 | 1591 | if (!has_target()) |
b1b12bab | 1592 | goto suspend; |
42d4dc3f | 1593 | |
2f0aea93 VK |
1594 | pr_debug("%s: Suspending Governors\n", __func__); |
1595 | ||
f963735a | 1596 | for_each_active_policy(policy) { |
2f0aea93 VK |
1597 | if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP)) |
1598 | pr_err("%s: Failed to stop governor for policy: %p\n", | |
1599 | __func__, policy); | |
1600 | else if (cpufreq_driver->suspend | |
1601 | && cpufreq_driver->suspend(policy)) | |
1602 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1603 | policy); | |
42d4dc3f | 1604 | } |
b1b12bab VK |
1605 | |
1606 | suspend: | |
1607 | cpufreq_suspended = true; | |
42d4dc3f BH |
1608 | } |
1609 | ||
1da177e4 | 1610 | /** |
2f0aea93 | 1611 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1612 | * |
2f0aea93 VK |
1613 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1614 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1615 | */ |
2f0aea93 | 1616 | void cpufreq_resume(void) |
1da177e4 | 1617 | { |
3a3e9e06 | 1618 | struct cpufreq_policy *policy; |
1da177e4 | 1619 | |
2f0aea93 VK |
1620 | if (!cpufreq_driver) |
1621 | return; | |
1da177e4 | 1622 | |
8e30444e LT |
1623 | cpufreq_suspended = false; |
1624 | ||
2f0aea93 | 1625 | if (!has_target()) |
e00e56df | 1626 | return; |
1da177e4 | 1627 | |
2f0aea93 | 1628 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1629 | |
f963735a | 1630 | for_each_active_policy(policy) { |
0c5aa405 VK |
1631 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) |
1632 | pr_err("%s: Failed to resume driver: %p\n", __func__, | |
1633 | policy); | |
1634 | else if (__cpufreq_governor(policy, CPUFREQ_GOV_START) | |
2f0aea93 VK |
1635 | || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS)) |
1636 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1637 | __func__, policy); | |
2f0aea93 | 1638 | } |
c75de0ac VK |
1639 | |
1640 | /* | |
1641 | * schedule call cpufreq_update_policy() for first-online CPU, as that | |
1642 | * wouldn't be hotplugged-out on suspend. It will verify that the | |
1643 | * current freq is in sync with what we believe it to be. | |
1644 | */ | |
1645 | policy = cpufreq_cpu_get_raw(cpumask_first(cpu_online_mask)); | |
1646 | if (WARN_ON(!policy)) | |
1647 | return; | |
1648 | ||
1649 | schedule_work(&policy->update); | |
2f0aea93 | 1650 | } |
1da177e4 | 1651 | |
9d95046e BP |
1652 | /** |
1653 | * cpufreq_get_current_driver - return current driver's name | |
1654 | * | |
1655 | * Return the name string of the currently loaded cpufreq driver | |
1656 | * or NULL, if none. | |
1657 | */ | |
1658 | const char *cpufreq_get_current_driver(void) | |
1659 | { | |
1c3d85dd RW |
1660 | if (cpufreq_driver) |
1661 | return cpufreq_driver->name; | |
1662 | ||
1663 | return NULL; | |
9d95046e BP |
1664 | } |
1665 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1666 | |
51315cdf TP |
1667 | /** |
1668 | * cpufreq_get_driver_data - return current driver data | |
1669 | * | |
1670 | * Return the private data of the currently loaded cpufreq | |
1671 | * driver, or NULL if no cpufreq driver is loaded. | |
1672 | */ | |
1673 | void *cpufreq_get_driver_data(void) | |
1674 | { | |
1675 | if (cpufreq_driver) | |
1676 | return cpufreq_driver->driver_data; | |
1677 | ||
1678 | return NULL; | |
1679 | } | |
1680 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1681 | ||
1da177e4 LT |
1682 | /********************************************************************* |
1683 | * NOTIFIER LISTS INTERFACE * | |
1684 | *********************************************************************/ | |
1685 | ||
1686 | /** | |
1687 | * cpufreq_register_notifier - register a driver with cpufreq | |
1688 | * @nb: notifier function to register | |
1689 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1690 | * | |
32ee8c3e | 1691 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1692 | * are notified about clock rate changes (once before and once after |
1693 | * the transition), or a list of drivers that are notified about | |
1694 | * changes in cpufreq policy. | |
1695 | * | |
1696 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1697 | * blocking_notifier_chain_register. |
1da177e4 LT |
1698 | */ |
1699 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1700 | { | |
1701 | int ret; | |
1702 | ||
d5aaffa9 DB |
1703 | if (cpufreq_disabled()) |
1704 | return -EINVAL; | |
1705 | ||
74212ca4 CEB |
1706 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1707 | ||
1da177e4 LT |
1708 | switch (list) { |
1709 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1710 | ret = srcu_notifier_chain_register( |
e041c683 | 1711 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1712 | break; |
1713 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1714 | ret = blocking_notifier_chain_register( |
1715 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1716 | break; |
1717 | default: | |
1718 | ret = -EINVAL; | |
1719 | } | |
1da177e4 LT |
1720 | |
1721 | return ret; | |
1722 | } | |
1723 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1724 | ||
1da177e4 LT |
1725 | /** |
1726 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1727 | * @nb: notifier block to be unregistered | |
bb176f7d | 1728 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1729 | * |
1730 | * Remove a driver from the CPU frequency notifier list. | |
1731 | * | |
1732 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1733 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1734 | */ |
1735 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1736 | { | |
1737 | int ret; | |
1738 | ||
d5aaffa9 DB |
1739 | if (cpufreq_disabled()) |
1740 | return -EINVAL; | |
1741 | ||
1da177e4 LT |
1742 | switch (list) { |
1743 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1744 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1745 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1746 | break; |
1747 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1748 | ret = blocking_notifier_chain_unregister( |
1749 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1750 | break; |
1751 | default: | |
1752 | ret = -EINVAL; | |
1753 | } | |
1da177e4 LT |
1754 | |
1755 | return ret; | |
1756 | } | |
1757 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1758 | ||
1759 | ||
1760 | /********************************************************************* | |
1761 | * GOVERNORS * | |
1762 | *********************************************************************/ | |
1763 | ||
1c03a2d0 VK |
1764 | /* Must set freqs->new to intermediate frequency */ |
1765 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1766 | struct cpufreq_freqs *freqs, int index) | |
1767 | { | |
1768 | int ret; | |
1769 | ||
1770 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1771 | ||
1772 | /* We don't need to switch to intermediate freq */ | |
1773 | if (!freqs->new) | |
1774 | return 0; | |
1775 | ||
1776 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1777 | __func__, policy->cpu, freqs->old, freqs->new); | |
1778 | ||
1779 | cpufreq_freq_transition_begin(policy, freqs); | |
1780 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1781 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1782 | ||
1783 | if (ret) | |
1784 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1785 | __func__, ret); | |
1786 | ||
1787 | return ret; | |
1788 | } | |
1789 | ||
8d65775d VK |
1790 | static int __target_index(struct cpufreq_policy *policy, |
1791 | struct cpufreq_frequency_table *freq_table, int index) | |
1792 | { | |
1c03a2d0 VK |
1793 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1794 | unsigned int intermediate_freq = 0; | |
8d65775d VK |
1795 | int retval = -EINVAL; |
1796 | bool notify; | |
1797 | ||
1798 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
8d65775d | 1799 | if (notify) { |
1c03a2d0 VK |
1800 | /* Handle switching to intermediate frequency */ |
1801 | if (cpufreq_driver->get_intermediate) { | |
1802 | retval = __target_intermediate(policy, &freqs, index); | |
1803 | if (retval) | |
1804 | return retval; | |
1805 | ||
1806 | intermediate_freq = freqs.new; | |
1807 | /* Set old freq to intermediate */ | |
1808 | if (intermediate_freq) | |
1809 | freqs.old = freqs.new; | |
1810 | } | |
8d65775d | 1811 | |
1c03a2d0 | 1812 | freqs.new = freq_table[index].frequency; |
8d65775d VK |
1813 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1814 | __func__, policy->cpu, freqs.old, freqs.new); | |
1815 | ||
1816 | cpufreq_freq_transition_begin(policy, &freqs); | |
1817 | } | |
1818 | ||
1819 | retval = cpufreq_driver->target_index(policy, index); | |
1820 | if (retval) | |
1821 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1822 | retval); | |
1823 | ||
1c03a2d0 | 1824 | if (notify) { |
8d65775d VK |
1825 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1826 | ||
1c03a2d0 VK |
1827 | /* |
1828 | * Failed after setting to intermediate freq? Driver should have | |
1829 | * reverted back to initial frequency and so should we. Check | |
1830 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1831 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1832 | */ |
1833 | if (unlikely(retval && intermediate_freq)) { | |
1834 | freqs.old = intermediate_freq; | |
1835 | freqs.new = policy->restore_freq; | |
1836 | cpufreq_freq_transition_begin(policy, &freqs); | |
1837 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1838 | } | |
1839 | } | |
1840 | ||
8d65775d VK |
1841 | return retval; |
1842 | } | |
1843 | ||
1da177e4 LT |
1844 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1845 | unsigned int target_freq, | |
1846 | unsigned int relation) | |
1847 | { | |
7249924e | 1848 | unsigned int old_target_freq = target_freq; |
8d65775d | 1849 | int retval = -EINVAL; |
c32b6b8e | 1850 | |
a7b422cd KRW |
1851 | if (cpufreq_disabled()) |
1852 | return -ENODEV; | |
1853 | ||
7249924e VK |
1854 | /* Make sure that target_freq is within supported range */ |
1855 | if (target_freq > policy->max) | |
1856 | target_freq = policy->max; | |
1857 | if (target_freq < policy->min) | |
1858 | target_freq = policy->min; | |
1859 | ||
1860 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1861 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1862 | |
9c0ebcf7 VK |
1863 | /* |
1864 | * This might look like a redundant call as we are checking it again | |
1865 | * after finding index. But it is left intentionally for cases where | |
1866 | * exactly same freq is called again and so we can save on few function | |
1867 | * calls. | |
1868 | */ | |
5a1c0228 VK |
1869 | if (target_freq == policy->cur) |
1870 | return 0; | |
1871 | ||
1c03a2d0 VK |
1872 | /* Save last value to restore later on errors */ |
1873 | policy->restore_freq = policy->cur; | |
1874 | ||
1c3d85dd RW |
1875 | if (cpufreq_driver->target) |
1876 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
9c0ebcf7 VK |
1877 | else if (cpufreq_driver->target_index) { |
1878 | struct cpufreq_frequency_table *freq_table; | |
1879 | int index; | |
90d45d17 | 1880 | |
9c0ebcf7 VK |
1881 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
1882 | if (unlikely(!freq_table)) { | |
1883 | pr_err("%s: Unable to find freq_table\n", __func__); | |
1884 | goto out; | |
1885 | } | |
1886 | ||
1887 | retval = cpufreq_frequency_table_target(policy, freq_table, | |
1888 | target_freq, relation, &index); | |
1889 | if (unlikely(retval)) { | |
1890 | pr_err("%s: Unable to find matching freq\n", __func__); | |
1891 | goto out; | |
1892 | } | |
1893 | ||
d4019f0a | 1894 | if (freq_table[index].frequency == policy->cur) { |
9c0ebcf7 | 1895 | retval = 0; |
d4019f0a VK |
1896 | goto out; |
1897 | } | |
1898 | ||
8d65775d | 1899 | retval = __target_index(policy, freq_table, index); |
9c0ebcf7 VK |
1900 | } |
1901 | ||
1902 | out: | |
1da177e4 LT |
1903 | return retval; |
1904 | } | |
1905 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1906 | ||
1da177e4 LT |
1907 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1908 | unsigned int target_freq, | |
1909 | unsigned int relation) | |
1910 | { | |
f1829e4a | 1911 | int ret = -EINVAL; |
1da177e4 | 1912 | |
ad7722da | 1913 | down_write(&policy->rwsem); |
1da177e4 LT |
1914 | |
1915 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1916 | ||
ad7722da | 1917 | up_write(&policy->rwsem); |
1da177e4 | 1918 | |
1da177e4 LT |
1919 | return ret; |
1920 | } | |
1921 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1922 | ||
e08f5f5b GS |
1923 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
1924 | unsigned int event) | |
1da177e4 | 1925 | { |
cc993cab | 1926 | int ret; |
6afde10c TR |
1927 | |
1928 | /* Only must be defined when default governor is known to have latency | |
1929 | restrictions, like e.g. conservative or ondemand. | |
1930 | That this is the case is already ensured in Kconfig | |
1931 | */ | |
1932 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
1933 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
1934 | #else | |
1935 | struct cpufreq_governor *gov = NULL; | |
1936 | #endif | |
1c256245 | 1937 | |
2f0aea93 VK |
1938 | /* Don't start any governor operations if we are entering suspend */ |
1939 | if (cpufreq_suspended) | |
1940 | return 0; | |
cb57720b EZ |
1941 | /* |
1942 | * Governor might not be initiated here if ACPI _PPC changed | |
1943 | * notification happened, so check it. | |
1944 | */ | |
1945 | if (!policy->governor) | |
1946 | return -EINVAL; | |
2f0aea93 | 1947 | |
1c256245 TR |
1948 | if (policy->governor->max_transition_latency && |
1949 | policy->cpuinfo.transition_latency > | |
1950 | policy->governor->max_transition_latency) { | |
6afde10c TR |
1951 | if (!gov) |
1952 | return -EINVAL; | |
1953 | else { | |
e837f9b5 JP |
1954 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
1955 | policy->governor->name, gov->name); | |
6afde10c TR |
1956 | policy->governor = gov; |
1957 | } | |
1c256245 | 1958 | } |
1da177e4 | 1959 | |
fe492f3f VK |
1960 | if (event == CPUFREQ_GOV_POLICY_INIT) |
1961 | if (!try_module_get(policy->governor->owner)) | |
1962 | return -EINVAL; | |
1da177e4 | 1963 | |
63431f78 | 1964 | pr_debug("%s: for CPU %u, event %u\n", __func__, policy->cpu, event); |
95731ebb XC |
1965 | |
1966 | mutex_lock(&cpufreq_governor_lock); | |
56d07db2 | 1967 | if ((policy->governor_enabled && event == CPUFREQ_GOV_START) |
f73d3933 VK |
1968 | || (!policy->governor_enabled |
1969 | && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) { | |
95731ebb XC |
1970 | mutex_unlock(&cpufreq_governor_lock); |
1971 | return -EBUSY; | |
1972 | } | |
1973 | ||
1974 | if (event == CPUFREQ_GOV_STOP) | |
1975 | policy->governor_enabled = false; | |
1976 | else if (event == CPUFREQ_GOV_START) | |
1977 | policy->governor_enabled = true; | |
1978 | ||
1979 | mutex_unlock(&cpufreq_governor_lock); | |
1980 | ||
1da177e4 LT |
1981 | ret = policy->governor->governor(policy, event); |
1982 | ||
4d5dcc42 VK |
1983 | if (!ret) { |
1984 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
1985 | policy->governor->initialized++; | |
1986 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
1987 | policy->governor->initialized--; | |
95731ebb XC |
1988 | } else { |
1989 | /* Restore original values */ | |
1990 | mutex_lock(&cpufreq_governor_lock); | |
1991 | if (event == CPUFREQ_GOV_STOP) | |
1992 | policy->governor_enabled = true; | |
1993 | else if (event == CPUFREQ_GOV_START) | |
1994 | policy->governor_enabled = false; | |
1995 | mutex_unlock(&cpufreq_governor_lock); | |
4d5dcc42 | 1996 | } |
b394058f | 1997 | |
fe492f3f VK |
1998 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
1999 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
2000 | module_put(policy->governor->owner); |
2001 | ||
2002 | return ret; | |
2003 | } | |
2004 | ||
1da177e4 LT |
2005 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2006 | { | |
3bcb09a3 | 2007 | int err; |
1da177e4 LT |
2008 | |
2009 | if (!governor) | |
2010 | return -EINVAL; | |
2011 | ||
a7b422cd KRW |
2012 | if (cpufreq_disabled()) |
2013 | return -ENODEV; | |
2014 | ||
3fc54d37 | 2015 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2016 | |
b394058f | 2017 | governor->initialized = 0; |
3bcb09a3 | 2018 | err = -EBUSY; |
42f91fa1 | 2019 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2020 | err = 0; |
2021 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2022 | } |
1da177e4 | 2023 | |
32ee8c3e | 2024 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2025 | return err; |
1da177e4 LT |
2026 | } |
2027 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2028 | ||
1da177e4 LT |
2029 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2030 | { | |
4573237b VK |
2031 | struct cpufreq_policy *policy; |
2032 | unsigned long flags; | |
90e41bac | 2033 | |
1da177e4 LT |
2034 | if (!governor) |
2035 | return; | |
2036 | ||
a7b422cd KRW |
2037 | if (cpufreq_disabled()) |
2038 | return; | |
2039 | ||
4573237b VK |
2040 | /* clear last_governor for all inactive policies */ |
2041 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2042 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2043 | if (!strcmp(policy->last_governor, governor->name)) { |
2044 | policy->governor = NULL; | |
4573237b | 2045 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2046 | } |
90e41bac | 2047 | } |
4573237b | 2048 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2049 | |
3fc54d37 | 2050 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2051 | list_del(&governor->governor_list); |
3fc54d37 | 2052 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2053 | return; |
2054 | } | |
2055 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2056 | ||
2057 | ||
1da177e4 LT |
2058 | /********************************************************************* |
2059 | * POLICY INTERFACE * | |
2060 | *********************************************************************/ | |
2061 | ||
2062 | /** | |
2063 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2064 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2065 | * is written | |
1da177e4 LT |
2066 | * |
2067 | * Reads the current cpufreq policy. | |
2068 | */ | |
2069 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2070 | { | |
2071 | struct cpufreq_policy *cpu_policy; | |
2072 | if (!policy) | |
2073 | return -EINVAL; | |
2074 | ||
2075 | cpu_policy = cpufreq_cpu_get(cpu); | |
2076 | if (!cpu_policy) | |
2077 | return -EINVAL; | |
2078 | ||
d5b73cd8 | 2079 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2080 | |
2081 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2082 | return 0; |
2083 | } | |
2084 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2085 | ||
153d7f3f | 2086 | /* |
037ce839 VK |
2087 | * policy : current policy. |
2088 | * new_policy: policy to be set. | |
153d7f3f | 2089 | */ |
037ce839 | 2090 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2091 | struct cpufreq_policy *new_policy) |
1da177e4 | 2092 | { |
d9a789c7 RW |
2093 | struct cpufreq_governor *old_gov; |
2094 | int ret; | |
1da177e4 | 2095 | |
e837f9b5 JP |
2096 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2097 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2098 | |
d5b73cd8 | 2099 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2100 | |
fba9573b PX |
2101 | /* |
2102 | * This check works well when we store new min/max freq attributes, | |
2103 | * because new_policy is a copy of policy with one field updated. | |
2104 | */ | |
2105 | if (new_policy->min > new_policy->max) | |
d9a789c7 | 2106 | return -EINVAL; |
9c9a43ed | 2107 | |
1da177e4 | 2108 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2109 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2110 | if (ret) |
d9a789c7 | 2111 | return ret; |
1da177e4 | 2112 | |
1da177e4 | 2113 | /* adjust if necessary - all reasons */ |
e041c683 | 2114 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2115 | CPUFREQ_ADJUST, new_policy); |
1da177e4 | 2116 | |
bb176f7d VK |
2117 | /* |
2118 | * verify the cpu speed can be set within this limit, which might be | |
2119 | * different to the first one | |
2120 | */ | |
3a3e9e06 | 2121 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2122 | if (ret) |
d9a789c7 | 2123 | return ret; |
1da177e4 LT |
2124 | |
2125 | /* notification of the new policy */ | |
e041c683 | 2126 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2127 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2128 | |
3a3e9e06 VK |
2129 | policy->min = new_policy->min; |
2130 | policy->max = new_policy->max; | |
1da177e4 | 2131 | |
2d06d8c4 | 2132 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2133 | policy->min, policy->max); |
1da177e4 | 2134 | |
1c3d85dd | 2135 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2136 | policy->policy = new_policy->policy; |
2d06d8c4 | 2137 | pr_debug("setting range\n"); |
d9a789c7 RW |
2138 | return cpufreq_driver->setpolicy(new_policy); |
2139 | } | |
1da177e4 | 2140 | |
d9a789c7 RW |
2141 | if (new_policy->governor == policy->governor) |
2142 | goto out; | |
7bd353a9 | 2143 | |
d9a789c7 RW |
2144 | pr_debug("governor switch\n"); |
2145 | ||
2146 | /* save old, working values */ | |
2147 | old_gov = policy->governor; | |
2148 | /* end old governor */ | |
2149 | if (old_gov) { | |
4bc384ae VK |
2150 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
2151 | if (ret) { | |
2152 | /* This can happen due to race with other operations */ | |
2153 | pr_debug("%s: Failed to Stop Governor: %s (%d)\n", | |
2154 | __func__, old_gov->name, ret); | |
2155 | return ret; | |
2156 | } | |
2157 | ||
d9a789c7 | 2158 | up_write(&policy->rwsem); |
4bc384ae | 2159 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
d9a789c7 | 2160 | down_write(&policy->rwsem); |
4bc384ae VK |
2161 | |
2162 | if (ret) { | |
2163 | pr_err("%s: Failed to Exit Governor: %s (%d)\n", | |
2164 | __func__, old_gov->name, ret); | |
2165 | return ret; | |
2166 | } | |
1da177e4 LT |
2167 | } |
2168 | ||
d9a789c7 RW |
2169 | /* start new governor */ |
2170 | policy->governor = new_policy->governor; | |
4bc384ae VK |
2171 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); |
2172 | if (!ret) { | |
2173 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
2174 | if (!ret) | |
d9a789c7 RW |
2175 | goto out; |
2176 | ||
2177 | up_write(&policy->rwsem); | |
2178 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
2179 | down_write(&policy->rwsem); | |
2180 | } | |
2181 | ||
2182 | /* new governor failed, so re-start old one */ | |
2183 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2184 | if (old_gov) { | |
2185 | policy->governor = old_gov; | |
4bc384ae VK |
2186 | if (__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) |
2187 | policy->governor = NULL; | |
2188 | else | |
2189 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
d9a789c7 RW |
2190 | } |
2191 | ||
4bc384ae | 2192 | return ret; |
d9a789c7 RW |
2193 | |
2194 | out: | |
2195 | pr_debug("governor: change or update limits\n"); | |
2196 | return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1da177e4 LT |
2197 | } |
2198 | ||
1da177e4 LT |
2199 | /** |
2200 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2201 | * @cpu: CPU which shall be re-evaluated | |
2202 | * | |
25985edc | 2203 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2204 | * at different times. |
2205 | */ | |
2206 | int cpufreq_update_policy(unsigned int cpu) | |
2207 | { | |
3a3e9e06 VK |
2208 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2209 | struct cpufreq_policy new_policy; | |
f1829e4a | 2210 | int ret; |
1da177e4 | 2211 | |
fefa8ff8 AP |
2212 | if (!policy) |
2213 | return -ENODEV; | |
1da177e4 | 2214 | |
ad7722da | 2215 | down_write(&policy->rwsem); |
1da177e4 | 2216 | |
2d06d8c4 | 2217 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2218 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2219 | new_policy.min = policy->user_policy.min; |
2220 | new_policy.max = policy->user_policy.max; | |
1da177e4 | 2221 | |
bb176f7d VK |
2222 | /* |
2223 | * BIOS might change freq behind our back | |
2224 | * -> ask driver for current freq and notify governors about a change | |
2225 | */ | |
2ed99e39 | 2226 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
3a3e9e06 | 2227 | new_policy.cur = cpufreq_driver->get(cpu); |
bd0fa9bb VK |
2228 | if (WARN_ON(!new_policy.cur)) { |
2229 | ret = -EIO; | |
fefa8ff8 | 2230 | goto unlock; |
bd0fa9bb VK |
2231 | } |
2232 | ||
3a3e9e06 | 2233 | if (!policy->cur) { |
e837f9b5 | 2234 | pr_debug("Driver did not initialize current freq\n"); |
3a3e9e06 | 2235 | policy->cur = new_policy.cur; |
a85f7bd3 | 2236 | } else { |
9c0ebcf7 | 2237 | if (policy->cur != new_policy.cur && has_target()) |
a1e1dc41 | 2238 | cpufreq_out_of_sync(policy, new_policy.cur); |
a85f7bd3 | 2239 | } |
0961dd0d TR |
2240 | } |
2241 | ||
037ce839 | 2242 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2243 | |
fefa8ff8 | 2244 | unlock: |
ad7722da | 2245 | up_write(&policy->rwsem); |
5a01f2e8 | 2246 | |
3a3e9e06 | 2247 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2248 | return ret; |
2249 | } | |
2250 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2251 | ||
2760984f | 2252 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2253 | unsigned long action, void *hcpu) |
2254 | { | |
2255 | unsigned int cpu = (unsigned long)hcpu; | |
c32b6b8e | 2256 | |
0b275352 RW |
2257 | switch (action & ~CPU_TASKS_FROZEN) { |
2258 | case CPU_ONLINE: | |
2259 | cpufreq_online(cpu); | |
2260 | break; | |
5302c3fb | 2261 | |
0b275352 RW |
2262 | case CPU_DOWN_PREPARE: |
2263 | cpufreq_offline_prepare(cpu); | |
2264 | break; | |
1aee40ac | 2265 | |
0b275352 RW |
2266 | case CPU_POST_DEAD: |
2267 | cpufreq_offline_finish(cpu); | |
2268 | break; | |
5302c3fb | 2269 | |
0b275352 RW |
2270 | case CPU_DOWN_FAILED: |
2271 | cpufreq_online(cpu); | |
2272 | break; | |
c32b6b8e AR |
2273 | } |
2274 | return NOTIFY_OK; | |
2275 | } | |
2276 | ||
9c36f746 | 2277 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2278 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2279 | }; |
1da177e4 | 2280 | |
6f19efc0 LM |
2281 | /********************************************************************* |
2282 | * BOOST * | |
2283 | *********************************************************************/ | |
2284 | static int cpufreq_boost_set_sw(int state) | |
2285 | { | |
2286 | struct cpufreq_frequency_table *freq_table; | |
2287 | struct cpufreq_policy *policy; | |
2288 | int ret = -EINVAL; | |
2289 | ||
f963735a | 2290 | for_each_active_policy(policy) { |
6f19efc0 LM |
2291 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2292 | if (freq_table) { | |
2293 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2294 | freq_table); | |
2295 | if (ret) { | |
2296 | pr_err("%s: Policy frequency update failed\n", | |
2297 | __func__); | |
2298 | break; | |
2299 | } | |
2300 | policy->user_policy.max = policy->max; | |
2301 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2302 | } | |
2303 | } | |
2304 | ||
2305 | return ret; | |
2306 | } | |
2307 | ||
2308 | int cpufreq_boost_trigger_state(int state) | |
2309 | { | |
2310 | unsigned long flags; | |
2311 | int ret = 0; | |
2312 | ||
2313 | if (cpufreq_driver->boost_enabled == state) | |
2314 | return 0; | |
2315 | ||
2316 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2317 | cpufreq_driver->boost_enabled = state; | |
2318 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2319 | ||
2320 | ret = cpufreq_driver->set_boost(state); | |
2321 | if (ret) { | |
2322 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2323 | cpufreq_driver->boost_enabled = !state; | |
2324 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2325 | ||
e837f9b5 JP |
2326 | pr_err("%s: Cannot %s BOOST\n", |
2327 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2328 | } |
2329 | ||
2330 | return ret; | |
2331 | } | |
2332 | ||
41669da0 | 2333 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2334 | { |
7a6c79f2 | 2335 | return likely(cpufreq_driver) && cpufreq_driver->set_boost; |
6f19efc0 | 2336 | } |
6f19efc0 | 2337 | |
44139ed4 VK |
2338 | static int create_boost_sysfs_file(void) |
2339 | { | |
2340 | int ret; | |
2341 | ||
c82bd444 | 2342 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2343 | if (ret) |
2344 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2345 | __func__); | |
2346 | ||
2347 | return ret; | |
2348 | } | |
2349 | ||
2350 | static void remove_boost_sysfs_file(void) | |
2351 | { | |
2352 | if (cpufreq_boost_supported()) | |
c82bd444 | 2353 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2354 | } |
2355 | ||
2356 | int cpufreq_enable_boost_support(void) | |
2357 | { | |
2358 | if (!cpufreq_driver) | |
2359 | return -EINVAL; | |
2360 | ||
2361 | if (cpufreq_boost_supported()) | |
2362 | return 0; | |
2363 | ||
7a6c79f2 | 2364 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2365 | |
2366 | /* This will get removed on driver unregister */ | |
2367 | return create_boost_sysfs_file(); | |
2368 | } | |
2369 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2370 | ||
6f19efc0 LM |
2371 | int cpufreq_boost_enabled(void) |
2372 | { | |
2373 | return cpufreq_driver->boost_enabled; | |
2374 | } | |
2375 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2376 | ||
1da177e4 LT |
2377 | /********************************************************************* |
2378 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2379 | *********************************************************************/ | |
2380 | ||
2381 | /** | |
2382 | * cpufreq_register_driver - register a CPU Frequency driver | |
2383 | * @driver_data: A struct cpufreq_driver containing the values# | |
2384 | * submitted by the CPU Frequency driver. | |
2385 | * | |
bb176f7d | 2386 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 2387 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 2388 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2389 | * |
2390 | */ | |
221dee28 | 2391 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2392 | { |
2393 | unsigned long flags; | |
2394 | int ret; | |
2395 | ||
a7b422cd KRW |
2396 | if (cpufreq_disabled()) |
2397 | return -ENODEV; | |
2398 | ||
1da177e4 | 2399 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2400 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2401 | driver_data->target) || |
2402 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2403 | driver_data->target)) || |
2404 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2405 | return -EINVAL; |
2406 | ||
2d06d8c4 | 2407 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2408 | |
fdd320da RW |
2409 | /* Protect against concurrent CPU online/offline. */ |
2410 | get_online_cpus(); | |
2411 | ||
0d1857a1 | 2412 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2413 | if (cpufreq_driver) { |
0d1857a1 | 2414 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2415 | ret = -EEXIST; |
2416 | goto out; | |
1da177e4 | 2417 | } |
1c3d85dd | 2418 | cpufreq_driver = driver_data; |
0d1857a1 | 2419 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2420 | |
bc68b7df VK |
2421 | if (driver_data->setpolicy) |
2422 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2423 | ||
7a6c79f2 RW |
2424 | if (cpufreq_boost_supported()) { |
2425 | ret = create_boost_sysfs_file(); | |
2426 | if (ret) | |
2427 | goto err_null_driver; | |
2428 | } | |
6f19efc0 | 2429 | |
8a25a2fd | 2430 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2431 | if (ret) |
6f19efc0 | 2432 | goto err_boost_unreg; |
1da177e4 | 2433 | |
ce1bcfe9 VK |
2434 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2435 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2436 | /* if all ->init() calls failed, unregister */ |
ce1bcfe9 VK |
2437 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2438 | driver_data->name); | |
2439 | goto err_if_unreg; | |
1da177e4 LT |
2440 | } |
2441 | ||
8f5bc2ab | 2442 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2443 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2444 | |
fdd320da RW |
2445 | out: |
2446 | put_online_cpus(); | |
2447 | return ret; | |
2448 | ||
8a25a2fd KS |
2449 | err_if_unreg: |
2450 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2451 | err_boost_unreg: |
44139ed4 | 2452 | remove_boost_sysfs_file(); |
8f5bc2ab | 2453 | err_null_driver: |
0d1857a1 | 2454 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2455 | cpufreq_driver = NULL; |
0d1857a1 | 2456 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da | 2457 | goto out; |
1da177e4 LT |
2458 | } |
2459 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2460 | ||
1da177e4 LT |
2461 | /** |
2462 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2463 | * | |
bb176f7d | 2464 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2465 | * the right to do so, i.e. if you have succeeded in initialising before! |
2466 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2467 | * currently not initialised. | |
2468 | */ | |
221dee28 | 2469 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2470 | { |
2471 | unsigned long flags; | |
2472 | ||
1c3d85dd | 2473 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2474 | return -EINVAL; |
1da177e4 | 2475 | |
2d06d8c4 | 2476 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2477 | |
454d3a25 SAS |
2478 | /* Protect against concurrent cpu hotplug */ |
2479 | get_online_cpus(); | |
8a25a2fd | 2480 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2481 | remove_boost_sysfs_file(); |
65edc68c | 2482 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2483 | |
0d1857a1 | 2484 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2485 | |
1c3d85dd | 2486 | cpufreq_driver = NULL; |
6eed9404 | 2487 | |
0d1857a1 | 2488 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
454d3a25 | 2489 | put_online_cpus(); |
1da177e4 LT |
2490 | |
2491 | return 0; | |
2492 | } | |
2493 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2494 | |
90de2a4a DA |
2495 | /* |
2496 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2497 | * or mutexes when secondary CPUs are halted. | |
2498 | */ | |
2499 | static struct syscore_ops cpufreq_syscore_ops = { | |
2500 | .shutdown = cpufreq_suspend, | |
2501 | }; | |
2502 | ||
c82bd444 VK |
2503 | struct kobject *cpufreq_global_kobject; |
2504 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2505 | ||
5a01f2e8 VP |
2506 | static int __init cpufreq_core_init(void) |
2507 | { | |
a7b422cd KRW |
2508 | if (cpufreq_disabled()) |
2509 | return -ENODEV; | |
2510 | ||
8eec1020 | 2511 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2512 | BUG_ON(!cpufreq_global_kobject); |
2513 | ||
90de2a4a DA |
2514 | register_syscore_ops(&cpufreq_syscore_ops); |
2515 | ||
5a01f2e8 VP |
2516 | return 0; |
2517 | } | |
5a01f2e8 | 2518 | core_initcall(cpufreq_core_init); |