Commit | Line | Data |
---|---|---|
d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/drivers/cpufreq/cpufreq.c | |
4 | * | |
5 | * Copyright (C) 2001 Russell King | |
6 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 7 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 8 | * |
c32b6b8e | 9 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 10 | * Added handling for CPU hotplug |
8ff69732 DJ |
11 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
12 | * Fix handling for CPU hotplug -- affected CPUs | |
1da177e4 LT |
13 | */ |
14 | ||
db701151 VK |
15 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
16 | ||
5ff0a268 | 17 | #include <linux/cpu.h> |
1da177e4 | 18 | #include <linux/cpufreq.h> |
5c238a8b | 19 | #include <linux/cpu_cooling.h> |
1da177e4 | 20 | #include <linux/delay.h> |
1da177e4 | 21 | #include <linux/device.h> |
5ff0a268 VK |
22 | #include <linux/init.h> |
23 | #include <linux/kernel_stat.h> | |
24 | #include <linux/module.h> | |
3fc54d37 | 25 | #include <linux/mutex.h> |
67d874c3 | 26 | #include <linux/pm_qos.h> |
5ff0a268 | 27 | #include <linux/slab.h> |
2f0aea93 | 28 | #include <linux/suspend.h> |
90de2a4a | 29 | #include <linux/syscore_ops.h> |
5ff0a268 | 30 | #include <linux/tick.h> |
6f4f2723 TR |
31 | #include <trace/events/power.h> |
32 | ||
b4f0676f | 33 | static LIST_HEAD(cpufreq_policy_list); |
f963735a | 34 | |
f963735a | 35 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
36 | #define for_each_suitable_policy(__policy, __active) \ |
37 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
38 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
39 | |
40 | #define for_each_active_policy(__policy) \ | |
41 | for_each_suitable_policy(__policy, true) | |
42 | #define for_each_inactive_policy(__policy) \ | |
43 | for_each_suitable_policy(__policy, false) | |
44 | ||
45 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
46 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
47 | ||
f7b27061 VK |
48 | /* Iterate over governors */ |
49 | static LIST_HEAD(cpufreq_governor_list); | |
50 | #define for_each_governor(__governor) \ | |
51 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
52 | ||
1da177e4 | 53 | /** |
cd878479 | 54 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
55 | * level driver of CPUFreq support, and its spinlock. This lock |
56 | * also protects the cpufreq_cpu_data array. | |
57 | */ | |
1c3d85dd | 58 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 59 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 60 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 61 | |
2f0aea93 VK |
62 | /* Flag to suspend/resume CPUFreq governors */ |
63 | static bool cpufreq_suspended; | |
1da177e4 | 64 | |
9c0ebcf7 VK |
65 | static inline bool has_target(void) |
66 | { | |
67 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
68 | } | |
69 | ||
1da177e4 | 70 | /* internal prototypes */ |
d92d50a4 | 71 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
72 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
73 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
0a300767 | 74 | static int cpufreq_start_governor(struct cpufreq_policy *policy); |
a92604b4 RW |
75 | static void cpufreq_stop_governor(struct cpufreq_policy *policy); |
76 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); | |
45482c70 | 77 | |
1da177e4 | 78 | /** |
32ee8c3e DJ |
79 | * Two notifier lists: the "policy" list is involved in the |
80 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
81 | * "transition" list for kernel code that needs to handle |
82 | * changes to devices when the CPU clock speed changes. | |
83 | * The mutex locks both lists. | |
84 | */ | |
e041c683 | 85 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 86 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 87 | |
a7b422cd | 88 | static int off __read_mostly; |
da584455 | 89 | static int cpufreq_disabled(void) |
a7b422cd KRW |
90 | { |
91 | return off; | |
92 | } | |
93 | void disable_cpufreq(void) | |
94 | { | |
95 | off = 1; | |
96 | } | |
29464f28 | 97 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 98 | |
4d5dcc42 VK |
99 | bool have_governor_per_policy(void) |
100 | { | |
0b981e70 | 101 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 102 | } |
3f869d6d | 103 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 104 | |
944e9a03 VK |
105 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
106 | { | |
107 | if (have_governor_per_policy()) | |
108 | return &policy->kobj; | |
109 | else | |
110 | return cpufreq_global_kobject; | |
111 | } | |
112 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
113 | ||
72a4ce34 VK |
114 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
115 | { | |
116 | u64 idle_time; | |
117 | u64 cur_wall_time; | |
118 | u64 busy_time; | |
119 | ||
7fb1327e | 120 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 VK |
121 | |
122 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
123 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
124 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
125 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
126 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
127 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
128 | ||
129 | idle_time = cur_wall_time - busy_time; | |
130 | if (wall) | |
7fb1327e | 131 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 132 | |
7fb1327e | 133 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
134 | } |
135 | ||
136 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
137 | { | |
138 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
139 | ||
140 | if (idle_time == -1ULL) | |
141 | return get_cpu_idle_time_jiffy(cpu, wall); | |
142 | else if (!io_busy) | |
143 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
144 | ||
145 | return idle_time; | |
146 | } | |
147 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
148 | ||
e7d5459d DE |
149 | __weak void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, |
150 | unsigned long max_freq) | |
151 | { | |
152 | } | |
153 | EXPORT_SYMBOL_GPL(arch_set_freq_scale); | |
154 | ||
70e9e778 VK |
155 | /* |
156 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
157 | * drivers of SMP systems. It will do following: | |
158 | * - validate & show freq table passed | |
159 | * - set policies transition latency | |
160 | * - policy->cpus with all possible CPUs | |
161 | */ | |
c4dcc8a1 | 162 | void cpufreq_generic_init(struct cpufreq_policy *policy, |
70e9e778 VK |
163 | struct cpufreq_frequency_table *table, |
164 | unsigned int transition_latency) | |
165 | { | |
92c99d15 | 166 | policy->freq_table = table; |
70e9e778 VK |
167 | policy->cpuinfo.transition_latency = transition_latency; |
168 | ||
169 | /* | |
58405af6 | 170 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
171 | * share the clock and voltage and clock. |
172 | */ | |
173 | cpumask_setall(policy->cpus); | |
70e9e778 VK |
174 | } |
175 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
176 | ||
1f0bd44e | 177 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
178 | { |
179 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
180 | ||
988bed09 VK |
181 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
182 | } | |
1f0bd44e | 183 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
184 | |
185 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
186 | { | |
187 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
188 | ||
652ed95d | 189 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
190 | pr_err("%s: No %s associated to cpu: %d\n", |
191 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
192 | return 0; |
193 | } | |
194 | ||
195 | return clk_get_rate(policy->clk) / 1000; | |
196 | } | |
197 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
198 | ||
50e9c852 | 199 | /** |
5d094fea RW |
200 | * cpufreq_cpu_get - Return policy for a CPU and mark it as busy. |
201 | * @cpu: CPU to find the policy for. | |
50e9c852 | 202 | * |
5d094fea RW |
203 | * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment |
204 | * the kobject reference counter of that policy. Return a valid policy on | |
205 | * success or NULL on failure. | |
50e9c852 | 206 | * |
5d094fea RW |
207 | * The policy returned by this function has to be released with the help of |
208 | * cpufreq_cpu_put() to balance its kobject reference counter properly. | |
50e9c852 | 209 | */ |
6eed9404 | 210 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 211 | { |
6eed9404 | 212 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
213 | unsigned long flags; |
214 | ||
1b947c90 | 215 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
216 | return NULL; |
217 | ||
1da177e4 | 218 | /* get the cpufreq driver */ |
1c3d85dd | 219 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 220 | |
6eed9404 VK |
221 | if (cpufreq_driver) { |
222 | /* get the CPU */ | |
988bed09 | 223 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
224 | if (policy) |
225 | kobject_get(&policy->kobj); | |
226 | } | |
1da177e4 | 227 | |
6eed9404 | 228 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 229 | |
3a3e9e06 | 230 | return policy; |
a9144436 | 231 | } |
1da177e4 LT |
232 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
233 | ||
50e9c852 | 234 | /** |
5d094fea RW |
235 | * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy. |
236 | * @policy: cpufreq policy returned by cpufreq_cpu_get(). | |
50e9c852 | 237 | */ |
3a3e9e06 | 238 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 239 | { |
6eed9404 | 240 | kobject_put(&policy->kobj); |
1da177e4 LT |
241 | } |
242 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
243 | ||
540a3758 RW |
244 | /** |
245 | * cpufreq_cpu_release - Unlock a policy and decrement its usage counter. | |
246 | * @policy: cpufreq policy returned by cpufreq_cpu_acquire(). | |
247 | */ | |
9083e498 | 248 | void cpufreq_cpu_release(struct cpufreq_policy *policy) |
540a3758 RW |
249 | { |
250 | if (WARN_ON(!policy)) | |
251 | return; | |
252 | ||
253 | lockdep_assert_held(&policy->rwsem); | |
254 | ||
255 | up_write(&policy->rwsem); | |
256 | ||
257 | cpufreq_cpu_put(policy); | |
258 | } | |
259 | ||
260 | /** | |
261 | * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it. | |
262 | * @cpu: CPU to find the policy for. | |
263 | * | |
264 | * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and | |
265 | * if the policy returned by it is not NULL, acquire its rwsem for writing. | |
266 | * Return the policy if it is active or release it and return NULL otherwise. | |
267 | * | |
268 | * The policy returned by this function has to be released with the help of | |
269 | * cpufreq_cpu_release() in order to release its rwsem and balance its usage | |
270 | * counter properly. | |
271 | */ | |
9083e498 | 272 | struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) |
540a3758 RW |
273 | { |
274 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
275 | ||
276 | if (!policy) | |
277 | return NULL; | |
278 | ||
279 | down_write(&policy->rwsem); | |
280 | ||
281 | if (policy_is_inactive(policy)) { | |
282 | cpufreq_cpu_release(policy); | |
283 | return NULL; | |
284 | } | |
285 | ||
286 | return policy; | |
287 | } | |
288 | ||
1da177e4 LT |
289 | /********************************************************************* |
290 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
291 | *********************************************************************/ | |
292 | ||
293 | /** | |
294 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
295 | * | |
296 | * This function alters the system "loops_per_jiffy" for the clock | |
297 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 298 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
299 | * per-CPU loops_per_jiffy value wherever possible. |
300 | */ | |
858119e1 | 301 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 302 | { |
39c132ee VK |
303 | #ifndef CONFIG_SMP |
304 | static unsigned long l_p_j_ref; | |
305 | static unsigned int l_p_j_ref_freq; | |
306 | ||
1da177e4 LT |
307 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
308 | return; | |
309 | ||
310 | if (!l_p_j_ref_freq) { | |
311 | l_p_j_ref = loops_per_jiffy; | |
312 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
313 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
314 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 315 | } |
0b443ead | 316 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
317 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
318 | ci->new); | |
e837f9b5 JP |
319 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
320 | loops_per_jiffy, ci->new); | |
1da177e4 | 321 | } |
1da177e4 | 322 | #endif |
39c132ee | 323 | } |
1da177e4 | 324 | |
20b5324d VK |
325 | /** |
326 | * cpufreq_notify_transition - Notify frequency transition and adjust_jiffies. | |
327 | * @policy: cpufreq policy to enable fast frequency switching for. | |
328 | * @freqs: contain details of the frequency update. | |
329 | * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
330 | * | |
331 | * This function calls the transition notifiers and the "adjust_jiffies" | |
332 | * function. It is called twice on all CPU frequency changes that have | |
333 | * external effects. | |
334 | */ | |
335 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
336 | struct cpufreq_freqs *freqs, | |
337 | unsigned int state) | |
1da177e4 | 338 | { |
df24014a VK |
339 | int cpu; |
340 | ||
1da177e4 LT |
341 | BUG_ON(irqs_disabled()); |
342 | ||
d5aaffa9 DB |
343 | if (cpufreq_disabled()) |
344 | return; | |
345 | ||
df24014a | 346 | freqs->policy = policy; |
1c3d85dd | 347 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 348 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 349 | state, freqs->new); |
1da177e4 | 350 | |
1da177e4 LT |
351 | switch (state) { |
352 | case CPUFREQ_PRECHANGE: | |
20b5324d VK |
353 | /* |
354 | * Detect if the driver reported a value as "old frequency" | |
e4472cb3 DJ |
355 | * which is not equal to what the cpufreq core thinks is |
356 | * "old frequency". | |
1da177e4 | 357 | */ |
98015228 VK |
358 | if (policy->cur && policy->cur != freqs->old) { |
359 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", | |
360 | freqs->old, policy->cur); | |
361 | freqs->old = policy->cur; | |
1da177e4 | 362 | } |
20b5324d | 363 | |
df24014a VK |
364 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
365 | CPUFREQ_PRECHANGE, freqs); | |
20b5324d | 366 | |
1da177e4 LT |
367 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
368 | break; | |
e4472cb3 | 369 | |
1da177e4 LT |
370 | case CPUFREQ_POSTCHANGE: |
371 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
20b5324d VK |
372 | pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, |
373 | cpumask_pr_args(policy->cpus)); | |
374 | ||
df24014a VK |
375 | for_each_cpu(cpu, policy->cpus) |
376 | trace_cpu_frequency(freqs->new, cpu); | |
377 | ||
378 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, | |
379 | CPUFREQ_POSTCHANGE, freqs); | |
20b5324d | 380 | |
1aefc75b | 381 | cpufreq_stats_record_transition(policy, freqs->new); |
20b5324d | 382 | policy->cur = freqs->new; |
1da177e4 | 383 | } |
1da177e4 | 384 | } |
bb176f7d | 385 | |
f7ba3b41 | 386 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 387 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
388 | struct cpufreq_freqs *freqs, int transition_failed) |
389 | { | |
390 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
391 | if (!transition_failed) | |
392 | return; | |
393 | ||
394 | swap(freqs->old, freqs->new); | |
395 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
396 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
397 | } | |
f7ba3b41 | 398 | |
12478cf0 SB |
399 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
400 | struct cpufreq_freqs *freqs) | |
401 | { | |
ca654dc3 SB |
402 | |
403 | /* | |
404 | * Catch double invocations of _begin() which lead to self-deadlock. | |
405 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
406 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
407 | * double invocations are very low. Moreover, there are scenarios | |
408 | * where these checks can emit false-positive warnings in these | |
409 | * drivers; so we avoid that by skipping them altogether. | |
410 | */ | |
411 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
412 | && current == policy->transition_task); | |
413 | ||
12478cf0 SB |
414 | wait: |
415 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
416 | ||
417 | spin_lock(&policy->transition_lock); | |
418 | ||
419 | if (unlikely(policy->transition_ongoing)) { | |
420 | spin_unlock(&policy->transition_lock); | |
421 | goto wait; | |
422 | } | |
423 | ||
424 | policy->transition_ongoing = true; | |
ca654dc3 | 425 | policy->transition_task = current; |
12478cf0 SB |
426 | |
427 | spin_unlock(&policy->transition_lock); | |
428 | ||
429 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
430 | } | |
431 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
432 | ||
433 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
434 | struct cpufreq_freqs *freqs, int transition_failed) | |
435 | { | |
0e7ea2f3 | 436 | if (WARN_ON(!policy->transition_ongoing)) |
12478cf0 SB |
437 | return; |
438 | ||
439 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
440 | ||
441 | policy->transition_ongoing = false; | |
ca654dc3 | 442 | policy->transition_task = NULL; |
12478cf0 SB |
443 | |
444 | wake_up(&policy->transition_wait); | |
445 | } | |
446 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
447 | ||
b7898fda RW |
448 | /* |
449 | * Fast frequency switching status count. Positive means "enabled", negative | |
450 | * means "disabled" and 0 means "not decided yet". | |
451 | */ | |
452 | static int cpufreq_fast_switch_count; | |
453 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
454 | ||
455 | static void cpufreq_list_transition_notifiers(void) | |
456 | { | |
457 | struct notifier_block *nb; | |
458 | ||
459 | pr_info("Registered transition notifiers:\n"); | |
460 | ||
461 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
462 | ||
463 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
d75f773c | 464 | pr_info("%pS\n", nb->notifier_call); |
b7898fda RW |
465 | |
466 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
467 | } | |
468 | ||
469 | /** | |
470 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
471 | * @policy: cpufreq policy to enable fast frequency switching for. | |
472 | * | |
473 | * Try to enable fast frequency switching for @policy. | |
474 | * | |
475 | * The attempt will fail if there is at least one transition notifier registered | |
476 | * at this point, as fast frequency switching is quite fundamentally at odds | |
477 | * with transition notifiers. Thus if successful, it will make registration of | |
478 | * transition notifiers fail going forward. | |
479 | */ | |
480 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
481 | { | |
482 | lockdep_assert_held(&policy->rwsem); | |
483 | ||
484 | if (!policy->fast_switch_possible) | |
485 | return; | |
486 | ||
487 | mutex_lock(&cpufreq_fast_switch_lock); | |
488 | if (cpufreq_fast_switch_count >= 0) { | |
489 | cpufreq_fast_switch_count++; | |
490 | policy->fast_switch_enabled = true; | |
491 | } else { | |
492 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
493 | policy->cpu); | |
494 | cpufreq_list_transition_notifiers(); | |
495 | } | |
496 | mutex_unlock(&cpufreq_fast_switch_lock); | |
497 | } | |
498 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
499 | ||
6c9d9c81 RW |
500 | /** |
501 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
502 | * @policy: cpufreq policy to disable fast frequency switching for. | |
503 | */ | |
504 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
505 | { |
506 | mutex_lock(&cpufreq_fast_switch_lock); | |
507 | if (policy->fast_switch_enabled) { | |
508 | policy->fast_switch_enabled = false; | |
509 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
510 | cpufreq_fast_switch_count--; | |
511 | } | |
512 | mutex_unlock(&cpufreq_fast_switch_lock); | |
513 | } | |
6c9d9c81 | 514 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 515 | |
e3c06236 SM |
516 | /** |
517 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
518 | * one. | |
519 | * @target_freq: target frequency to resolve. | |
520 | * | |
521 | * The target to driver frequency mapping is cached in the policy. | |
522 | * | |
523 | * Return: Lowest driver-supported frequency greater than or equal to the | |
524 | * given target_freq, subject to policy (min/max) and driver limitations. | |
525 | */ | |
526 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
527 | unsigned int target_freq) | |
528 | { | |
529 | target_freq = clamp_val(target_freq, policy->min, policy->max); | |
530 | policy->cached_target_freq = target_freq; | |
abe8bd02 VK |
531 | |
532 | if (cpufreq_driver->target_index) { | |
533 | int idx; | |
534 | ||
535 | idx = cpufreq_frequency_table_target(policy, target_freq, | |
536 | CPUFREQ_RELATION_L); | |
537 | policy->cached_resolved_idx = idx; | |
538 | return policy->freq_table[idx].frequency; | |
539 | } | |
540 | ||
e3c06236 SM |
541 | if (cpufreq_driver->resolve_freq) |
542 | return cpufreq_driver->resolve_freq(policy, target_freq); | |
abe8bd02 VK |
543 | |
544 | return target_freq; | |
e3c06236 | 545 | } |
ae2c1ca6 | 546 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 547 | |
aa7519af VK |
548 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
549 | { | |
550 | unsigned int latency; | |
551 | ||
552 | if (policy->transition_delay_us) | |
553 | return policy->transition_delay_us; | |
554 | ||
555 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
556 | if (latency) { |
557 | /* | |
558 | * For platforms that can change the frequency very fast (< 10 | |
559 | * us), the above formula gives a decent transition delay. But | |
560 | * for platforms where transition_latency is in milliseconds, it | |
561 | * ends up giving unrealistic values. | |
562 | * | |
563 | * Cap the default transition delay to 10 ms, which seems to be | |
564 | * a reasonable amount of time after which we should reevaluate | |
565 | * the frequency. | |
566 | */ | |
567 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
568 | } | |
aa7519af VK |
569 | |
570 | return LATENCY_MULTIPLIER; | |
571 | } | |
572 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
573 | ||
1da177e4 LT |
574 | /********************************************************************* |
575 | * SYSFS INTERFACE * | |
576 | *********************************************************************/ | |
8a5c74a1 | 577 | static ssize_t show_boost(struct kobject *kobj, |
625c85a6 | 578 | struct kobj_attribute *attr, char *buf) |
6f19efc0 LM |
579 | { |
580 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
581 | } | |
582 | ||
625c85a6 VK |
583 | static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, |
584 | const char *buf, size_t count) | |
6f19efc0 LM |
585 | { |
586 | int ret, enable; | |
587 | ||
588 | ret = sscanf(buf, "%d", &enable); | |
589 | if (ret != 1 || enable < 0 || enable > 1) | |
590 | return -EINVAL; | |
591 | ||
592 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
593 | pr_err("%s: Cannot %s BOOST!\n", |
594 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
595 | return -EINVAL; |
596 | } | |
597 | ||
e837f9b5 JP |
598 | pr_debug("%s: cpufreq BOOST %s\n", |
599 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
600 | |
601 | return count; | |
602 | } | |
603 | define_one_global_rw(boost); | |
1da177e4 | 604 | |
42f91fa1 | 605 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
606 | { |
607 | struct cpufreq_governor *t; | |
608 | ||
f7b27061 | 609 | for_each_governor(t) |
7c4f4539 | 610 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
611 | return t; |
612 | ||
613 | return NULL; | |
614 | } | |
615 | ||
ab05d97a YH |
616 | static int cpufreq_parse_policy(char *str_governor, |
617 | struct cpufreq_policy *policy) | |
618 | { | |
619 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { | |
620 | policy->policy = CPUFREQ_POLICY_PERFORMANCE; | |
621 | return 0; | |
622 | } | |
623 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) { | |
624 | policy->policy = CPUFREQ_POLICY_POWERSAVE; | |
625 | return 0; | |
626 | } | |
627 | return -EINVAL; | |
628 | } | |
629 | ||
1da177e4 | 630 | /** |
5ddc6d4e | 631 | * cpufreq_parse_governor - parse a governor string only for has_target() |
1da177e4 | 632 | */ |
ae0ff89f RW |
633 | static int cpufreq_parse_governor(char *str_governor, |
634 | struct cpufreq_policy *policy) | |
1da177e4 | 635 | { |
ab05d97a | 636 | struct cpufreq_governor *t; |
045149e6 | 637 | |
ab05d97a | 638 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 639 | |
ab05d97a YH |
640 | t = find_governor(str_governor); |
641 | if (!t) { | |
642 | int ret; | |
3bcb09a3 | 643 | |
ab05d97a | 644 | mutex_unlock(&cpufreq_governor_mutex); |
045149e6 | 645 | |
ab05d97a YH |
646 | ret = request_module("cpufreq_%s", str_governor); |
647 | if (ret) | |
648 | return -EINVAL; | |
045149e6 | 649 | |
ab05d97a | 650 | mutex_lock(&cpufreq_governor_mutex); |
ea714970 | 651 | |
ab05d97a YH |
652 | t = find_governor(str_governor); |
653 | } | |
654 | if (t && !try_module_get(t->owner)) | |
655 | t = NULL; | |
ea714970 | 656 | |
ab05d97a | 657 | mutex_unlock(&cpufreq_governor_mutex); |
045149e6 | 658 | |
ab05d97a YH |
659 | if (t) { |
660 | policy->governor = t; | |
661 | return 0; | |
1da177e4 | 662 | } |
045149e6 RW |
663 | |
664 | return -EINVAL; | |
1da177e4 | 665 | } |
1da177e4 | 666 | |
1da177e4 | 667 | /** |
e08f5f5b GS |
668 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
669 | * print out cpufreq information | |
1da177e4 LT |
670 | * |
671 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
672 | * "unsigned int". | |
673 | */ | |
674 | ||
32ee8c3e DJ |
675 | #define show_one(file_name, object) \ |
676 | static ssize_t show_##file_name \ | |
905d77cd | 677 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 678 | { \ |
29464f28 | 679 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
680 | } |
681 | ||
682 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
683 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 684 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
685 | show_one(scaling_min_freq, min); |
686 | show_one(scaling_max_freq, max); | |
c034b02e | 687 | |
f8475cef LB |
688 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
689 | { | |
690 | return 0; | |
691 | } | |
692 | ||
09347b29 | 693 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
694 | { |
695 | ssize_t ret; | |
f8475cef | 696 | unsigned int freq; |
c034b02e | 697 | |
f8475cef LB |
698 | freq = arch_freq_get_on_cpu(policy->cpu); |
699 | if (freq) | |
700 | ret = sprintf(buf, "%u\n", freq); | |
701 | else if (cpufreq_driver && cpufreq_driver->setpolicy && | |
702 | cpufreq_driver->get) | |
c034b02e DB |
703 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
704 | else | |
705 | ret = sprintf(buf, "%u\n", policy->cur); | |
706 | return ret; | |
707 | } | |
1da177e4 LT |
708 | |
709 | /** | |
710 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
711 | */ | |
712 | #define store_one(file_name, object) \ | |
713 | static ssize_t store_##file_name \ | |
905d77cd | 714 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 715 | { \ |
18c49926 VK |
716 | unsigned long val; \ |
717 | int ret; \ | |
1da177e4 | 718 | \ |
18c49926 | 719 | ret = sscanf(buf, "%lu", &val); \ |
1da177e4 LT |
720 | if (ret != 1) \ |
721 | return -EINVAL; \ | |
722 | \ | |
18c49926 VK |
723 | ret = dev_pm_qos_update_request(policy->object##_freq_req, val);\ |
724 | return ret >= 0 ? count : ret; \ | |
1da177e4 LT |
725 | } |
726 | ||
29464f28 DJ |
727 | store_one(scaling_min_freq, min); |
728 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
729 | |
730 | /** | |
731 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
732 | */ | |
905d77cd DJ |
733 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
734 | char *buf) | |
1da177e4 | 735 | { |
d92d50a4 | 736 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
737 | |
738 | if (cur_freq) | |
739 | return sprintf(buf, "%u\n", cur_freq); | |
740 | ||
741 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
742 | } |
743 | ||
1da177e4 LT |
744 | /** |
745 | * show_scaling_governor - show the current policy for the specified CPU | |
746 | */ | |
905d77cd | 747 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 748 | { |
29464f28 | 749 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
750 | return sprintf(buf, "powersave\n"); |
751 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
752 | return sprintf(buf, "performance\n"); | |
753 | else if (policy->governor) | |
4b972f0b | 754 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 755 | policy->governor->name); |
1da177e4 LT |
756 | return -EINVAL; |
757 | } | |
758 | ||
1da177e4 LT |
759 | /** |
760 | * store_scaling_governor - store policy for the specified CPU | |
761 | */ | |
905d77cd DJ |
762 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
763 | const char *buf, size_t count) | |
1da177e4 | 764 | { |
5136fa56 | 765 | int ret; |
1da177e4 LT |
766 | char str_governor[16]; |
767 | struct cpufreq_policy new_policy; | |
768 | ||
8fa5b631 | 769 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 770 | |
29464f28 | 771 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
772 | if (ret != 1) |
773 | return -EINVAL; | |
774 | ||
ab05d97a YH |
775 | if (cpufreq_driver->setpolicy) { |
776 | if (cpufreq_parse_policy(str_governor, &new_policy)) | |
777 | return -EINVAL; | |
778 | } else { | |
779 | if (cpufreq_parse_governor(str_governor, &new_policy)) | |
780 | return -EINVAL; | |
781 | } | |
1da177e4 | 782 | |
037ce839 | 783 | ret = cpufreq_set_policy(policy, &new_policy); |
a8b149d3 RW |
784 | |
785 | if (new_policy.governor) | |
786 | module_put(new_policy.governor->owner); | |
787 | ||
88dc4384 | 788 | return ret ? ret : count; |
1da177e4 LT |
789 | } |
790 | ||
791 | /** | |
792 | * show_scaling_driver - show the cpufreq driver currently loaded | |
793 | */ | |
905d77cd | 794 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 795 | { |
1c3d85dd | 796 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
797 | } |
798 | ||
799 | /** | |
800 | * show_scaling_available_governors - show the available CPUfreq governors | |
801 | */ | |
905d77cd DJ |
802 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
803 | char *buf) | |
1da177e4 LT |
804 | { |
805 | ssize_t i = 0; | |
806 | struct cpufreq_governor *t; | |
807 | ||
9c0ebcf7 | 808 | if (!has_target()) { |
1da177e4 LT |
809 | i += sprintf(buf, "performance powersave"); |
810 | goto out; | |
811 | } | |
812 | ||
f7b27061 | 813 | for_each_governor(t) { |
29464f28 DJ |
814 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
815 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 816 | goto out; |
4b972f0b | 817 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 818 | } |
7d5e350f | 819 | out: |
1da177e4 LT |
820 | i += sprintf(&buf[i], "\n"); |
821 | return i; | |
822 | } | |
e8628dd0 | 823 | |
f4fd3797 | 824 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
825 | { |
826 | ssize_t i = 0; | |
827 | unsigned int cpu; | |
828 | ||
835481d9 | 829 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
830 | if (i) |
831 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
832 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
833 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 834 | break; |
1da177e4 LT |
835 | } |
836 | i += sprintf(&buf[i], "\n"); | |
837 | return i; | |
838 | } | |
f4fd3797 | 839 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 840 | |
e8628dd0 DW |
841 | /** |
842 | * show_related_cpus - show the CPUs affected by each transition even if | |
843 | * hw coordination is in use | |
844 | */ | |
845 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
846 | { | |
f4fd3797 | 847 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
848 | } |
849 | ||
850 | /** | |
851 | * show_affected_cpus - show the CPUs affected by each transition | |
852 | */ | |
853 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
854 | { | |
f4fd3797 | 855 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
856 | } |
857 | ||
9e76988e | 858 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 859 | const char *buf, size_t count) |
9e76988e VP |
860 | { |
861 | unsigned int freq = 0; | |
862 | unsigned int ret; | |
863 | ||
879000f9 | 864 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
865 | return -EINVAL; |
866 | ||
867 | ret = sscanf(buf, "%u", &freq); | |
868 | if (ret != 1) | |
869 | return -EINVAL; | |
870 | ||
871 | policy->governor->store_setspeed(policy, freq); | |
872 | ||
873 | return count; | |
874 | } | |
875 | ||
876 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
877 | { | |
879000f9 | 878 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
879 | return sprintf(buf, "<unsupported>\n"); |
880 | ||
881 | return policy->governor->show_setspeed(policy, buf); | |
882 | } | |
1da177e4 | 883 | |
e2f74f35 | 884 | /** |
8bf1ac72 | 885 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
886 | */ |
887 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
888 | { | |
889 | unsigned int limit; | |
890 | int ret; | |
b23aa311 YH |
891 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
892 | if (!ret) | |
893 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
894 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
895 | } | |
896 | ||
6dad2a29 BP |
897 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
898 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
899 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
900 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
901 | cpufreq_freq_attr_ro(scaling_available_governors); | |
902 | cpufreq_freq_attr_ro(scaling_driver); | |
903 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
904 | cpufreq_freq_attr_ro(bios_limit); | |
905 | cpufreq_freq_attr_ro(related_cpus); | |
906 | cpufreq_freq_attr_ro(affected_cpus); | |
907 | cpufreq_freq_attr_rw(scaling_min_freq); | |
908 | cpufreq_freq_attr_rw(scaling_max_freq); | |
909 | cpufreq_freq_attr_rw(scaling_governor); | |
910 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 911 | |
905d77cd | 912 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
913 | &cpuinfo_min_freq.attr, |
914 | &cpuinfo_max_freq.attr, | |
ed129784 | 915 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
916 | &scaling_min_freq.attr, |
917 | &scaling_max_freq.attr, | |
918 | &affected_cpus.attr, | |
e8628dd0 | 919 | &related_cpus.attr, |
1da177e4 LT |
920 | &scaling_governor.attr, |
921 | &scaling_driver.attr, | |
922 | &scaling_available_governors.attr, | |
9e76988e | 923 | &scaling_setspeed.attr, |
1da177e4 LT |
924 | NULL |
925 | }; | |
926 | ||
29464f28 DJ |
927 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
928 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 929 | |
29464f28 | 930 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 931 | { |
905d77cd DJ |
932 | struct cpufreq_policy *policy = to_policy(kobj); |
933 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 934 | ssize_t ret; |
6eed9404 | 935 | |
ad7722da | 936 | down_read(&policy->rwsem); |
6541aef0 | 937 | ret = fattr->show(policy, buf); |
ad7722da | 938 | up_read(&policy->rwsem); |
1b750e3b | 939 | |
1da177e4 LT |
940 | return ret; |
941 | } | |
942 | ||
905d77cd DJ |
943 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
944 | const char *buf, size_t count) | |
1da177e4 | 945 | { |
905d77cd DJ |
946 | struct cpufreq_policy *policy = to_policy(kobj); |
947 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 948 | ssize_t ret = -EINVAL; |
6eed9404 | 949 | |
9b3d9bb3 WL |
950 | /* |
951 | * cpus_read_trylock() is used here to work around a circular lock | |
952 | * dependency problem with respect to the cpufreq_register_driver(). | |
953 | */ | |
954 | if (!cpus_read_trylock()) | |
955 | return -EBUSY; | |
4f750c93 | 956 | |
6541aef0 RW |
957 | if (cpu_online(policy->cpu)) { |
958 | down_write(&policy->rwsem); | |
e08f5f5b | 959 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
960 | up_write(&policy->rwsem); |
961 | } | |
e08f5f5b | 962 | |
a92551e4 | 963 | cpus_read_unlock(); |
4f750c93 | 964 | |
1da177e4 LT |
965 | return ret; |
966 | } | |
967 | ||
905d77cd | 968 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 969 | { |
905d77cd | 970 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 971 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
972 | complete(&policy->kobj_unregister); |
973 | } | |
974 | ||
52cf25d0 | 975 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
976 | .show = show, |
977 | .store = store, | |
978 | }; | |
979 | ||
980 | static struct kobj_type ktype_cpufreq = { | |
981 | .sysfs_ops = &sysfs_ops, | |
982 | .default_attrs = default_attrs, | |
983 | .release = cpufreq_sysfs_release, | |
984 | }; | |
985 | ||
2f0ba790 | 986 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) |
87549141 | 987 | { |
2f0ba790 RW |
988 | struct device *dev = get_cpu_device(cpu); |
989 | ||
67d874c3 | 990 | if (unlikely(!dev)) |
2f0ba790 RW |
991 | return; |
992 | ||
993 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
994 | return; | |
995 | ||
26619804 | 996 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
997 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
998 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
999 | } |
1000 | ||
26619804 VK |
1001 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
1002 | struct device *dev) | |
87549141 | 1003 | { |
26619804 VK |
1004 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1005 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
1006 | } |
1007 | ||
d9612a49 | 1008 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
1009 | { |
1010 | struct freq_attr **drv_attr; | |
909a694e | 1011 | int ret = 0; |
909a694e | 1012 | |
909a694e | 1013 | /* set up files for this cpu device */ |
1c3d85dd | 1014 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1015 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1016 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1017 | if (ret) | |
6d4e81ed | 1018 | return ret; |
909a694e DJ |
1019 | drv_attr++; |
1020 | } | |
1c3d85dd | 1021 | if (cpufreq_driver->get) { |
909a694e DJ |
1022 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1023 | if (ret) | |
6d4e81ed | 1024 | return ret; |
909a694e | 1025 | } |
c034b02e DB |
1026 | |
1027 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1028 | if (ret) | |
6d4e81ed | 1029 | return ret; |
c034b02e | 1030 | |
1c3d85dd | 1031 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1032 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1033 | if (ret) | |
6d4e81ed | 1034 | return ret; |
e2f74f35 | 1035 | } |
909a694e | 1036 | |
26619804 | 1037 | return 0; |
e18f1682 SB |
1038 | } |
1039 | ||
de1df26b RW |
1040 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
1041 | { | |
1042 | return NULL; | |
1043 | } | |
1044 | ||
7f0fa40f | 1045 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1046 | { |
ab05d97a | 1047 | struct cpufreq_governor *gov = NULL, *def_gov = NULL; |
e18f1682 | 1048 | struct cpufreq_policy new_policy; |
e18f1682 | 1049 | |
d5b73cd8 | 1050 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 1051 | |
ab05d97a YH |
1052 | def_gov = cpufreq_default_governor(); |
1053 | ||
1054 | if (has_target()) { | |
1055 | /* | |
1056 | * Update governor of new_policy to the governor used before | |
1057 | * hotplug | |
1058 | */ | |
1059 | gov = find_governor(policy->last_governor); | |
1060 | if (gov) { | |
1061 | pr_debug("Restoring governor %s for cpu %d\n", | |
6e2c89d1 | 1062 | policy->governor->name, policy->cpu); |
ab05d97a YH |
1063 | } else { |
1064 | if (!def_gov) | |
1065 | return -ENODATA; | |
1066 | gov = def_gov; | |
1067 | } | |
1068 | new_policy.governor = gov; | |
de1df26b | 1069 | } else { |
ab05d97a YH |
1070 | /* Use the default policy if there is no last_policy. */ |
1071 | if (policy->last_policy) { | |
69030dd1 | 1072 | new_policy.policy = policy->last_policy; |
ab05d97a YH |
1073 | } else { |
1074 | if (!def_gov) | |
1075 | return -ENODATA; | |
1076 | cpufreq_parse_policy(def_gov->name, &new_policy); | |
1077 | } | |
69030dd1 | 1078 | } |
ab05d97a | 1079 | |
7f0fa40f | 1080 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
1081 | } |
1082 | ||
d9612a49 | 1083 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1084 | { |
9c0ebcf7 | 1085 | int ret = 0; |
fcf80582 | 1086 | |
bb29ae15 VK |
1087 | /* Has this CPU been taken care of already? */ |
1088 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1089 | return 0; | |
1090 | ||
49f18560 | 1091 | down_write(&policy->rwsem); |
45482c70 RW |
1092 | if (has_target()) |
1093 | cpufreq_stop_governor(policy); | |
fcf80582 | 1094 | |
fcf80582 | 1095 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1096 | |
9c0ebcf7 | 1097 | if (has_target()) { |
0a300767 | 1098 | ret = cpufreq_start_governor(policy); |
49f18560 | 1099 | if (ret) |
3de9bdeb | 1100 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1101 | } |
49f18560 VK |
1102 | up_write(&policy->rwsem); |
1103 | return ret; | |
fcf80582 | 1104 | } |
1da177e4 | 1105 | |
c57b25bd | 1106 | void refresh_frequency_limits(struct cpufreq_policy *policy) |
70a59fde | 1107 | { |
67d874c3 | 1108 | struct cpufreq_policy new_policy; |
70a59fde | 1109 | |
67d874c3 VK |
1110 | if (!policy_is_inactive(policy)) { |
1111 | new_policy = *policy; | |
1112 | pr_debug("updating policy for CPU %u\n", policy->cpu); | |
70a59fde | 1113 | |
67d874c3 VK |
1114 | cpufreq_set_policy(policy, &new_policy); |
1115 | } | |
70a59fde | 1116 | } |
c57b25bd | 1117 | EXPORT_SYMBOL(refresh_frequency_limits); |
70a59fde | 1118 | |
11eb69b9 VK |
1119 | static void handle_update(struct work_struct *work) |
1120 | { | |
1121 | struct cpufreq_policy *policy = | |
1122 | container_of(work, struct cpufreq_policy, update); | |
70a59fde VK |
1123 | |
1124 | pr_debug("handle_update for cpu %u called\n", policy->cpu); | |
67d874c3 | 1125 | down_write(&policy->rwsem); |
70a59fde | 1126 | refresh_frequency_limits(policy); |
67d874c3 VK |
1127 | up_write(&policy->rwsem); |
1128 | } | |
1129 | ||
1130 | static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq, | |
1131 | void *data) | |
1132 | { | |
1133 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min); | |
1134 | ||
1135 | schedule_work(&policy->update); | |
1136 | return 0; | |
1137 | } | |
1138 | ||
1139 | static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq, | |
1140 | void *data) | |
1141 | { | |
1142 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max); | |
1143 | ||
1144 | schedule_work(&policy->update); | |
1145 | return 0; | |
1146 | } | |
1147 | ||
1148 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) | |
1149 | { | |
1150 | struct kobject *kobj; | |
1151 | struct completion *cmp; | |
1152 | ||
1153 | down_write(&policy->rwsem); | |
1154 | cpufreq_stats_free_table(policy); | |
1155 | kobj = &policy->kobj; | |
1156 | cmp = &policy->kobj_unregister; | |
1157 | up_write(&policy->rwsem); | |
1158 | kobject_put(kobj); | |
1159 | ||
1160 | /* | |
1161 | * We need to make sure that the underlying kobj is | |
1162 | * actually not referenced anymore by anybody before we | |
1163 | * proceed with unloading. | |
1164 | */ | |
1165 | pr_debug("waiting for dropping of refcount\n"); | |
1166 | wait_for_completion(cmp); | |
1167 | pr_debug("wait complete\n"); | |
fcf80582 | 1168 | } |
1da177e4 | 1169 | |
a34e63b1 | 1170 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1171 | { |
1172 | struct cpufreq_policy *policy; | |
67d874c3 | 1173 | struct device *dev = get_cpu_device(cpu); |
edd4a893 | 1174 | int ret; |
e9698cc5 | 1175 | |
67d874c3 VK |
1176 | if (!dev) |
1177 | return NULL; | |
1178 | ||
e9698cc5 SB |
1179 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1180 | if (!policy) | |
1181 | return NULL; | |
1182 | ||
1183 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1184 | goto err_free_policy; | |
1185 | ||
1186 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1187 | goto err_free_cpumask; | |
1188 | ||
559ed407 RW |
1189 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1190 | goto err_free_rcpumask; | |
1191 | ||
edd4a893 VK |
1192 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1193 | cpufreq_global_kobject, "policy%u", cpu); | |
1194 | if (ret) { | |
67d874c3 | 1195 | dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret); |
2acb9bda RW |
1196 | /* |
1197 | * The entire policy object will be freed below, but the extra | |
1198 | * memory allocated for the kobject name needs to be freed by | |
1199 | * releasing the kobject. | |
1200 | */ | |
4ebe36c9 | 1201 | kobject_put(&policy->kobj); |
edd4a893 VK |
1202 | goto err_free_real_cpus; |
1203 | } | |
1204 | ||
67d874c3 VK |
1205 | policy->nb_min.notifier_call = cpufreq_notifier_min; |
1206 | policy->nb_max.notifier_call = cpufreq_notifier_max; | |
1207 | ||
1208 | ret = dev_pm_qos_add_notifier(dev, &policy->nb_min, | |
1209 | DEV_PM_QOS_MIN_FREQUENCY); | |
1210 | if (ret) { | |
1211 | dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n", | |
1212 | ret, cpumask_pr_args(policy->cpus)); | |
1213 | goto err_kobj_remove; | |
1214 | } | |
1215 | ||
1216 | ret = dev_pm_qos_add_notifier(dev, &policy->nb_max, | |
1217 | DEV_PM_QOS_MAX_FREQUENCY); | |
1218 | if (ret) { | |
1219 | dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n", | |
1220 | ret, cpumask_pr_args(policy->cpus)); | |
1221 | goto err_min_qos_notifier; | |
1222 | } | |
1223 | ||
c88a1f8b | 1224 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1225 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1226 | spin_lock_init(&policy->transition_lock); |
1227 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1228 | init_completion(&policy->kobj_unregister); |
1229 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1230 | |
a34e63b1 | 1231 | policy->cpu = cpu; |
e9698cc5 SB |
1232 | return policy; |
1233 | ||
67d874c3 VK |
1234 | err_min_qos_notifier: |
1235 | dev_pm_qos_remove_notifier(dev, &policy->nb_min, | |
1236 | DEV_PM_QOS_MIN_FREQUENCY); | |
1237 | err_kobj_remove: | |
1238 | cpufreq_policy_put_kobj(policy); | |
edd4a893 VK |
1239 | err_free_real_cpus: |
1240 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1241 | err_free_rcpumask: |
1242 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1243 | err_free_cpumask: |
1244 | free_cpumask_var(policy->cpus); | |
1245 | err_free_policy: | |
1246 | kfree(policy); | |
1247 | ||
1248 | return NULL; | |
1249 | } | |
1250 | ||
f9f41e3e | 1251 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1252 | { |
67d874c3 | 1253 | struct device *dev = get_cpu_device(policy->cpu); |
988bed09 VK |
1254 | unsigned long flags; |
1255 | int cpu; | |
1256 | ||
1257 | /* Remove policy from list */ | |
1258 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1259 | list_del(&policy->policy_list); | |
1260 | ||
1261 | for_each_cpu(cpu, policy->related_cpus) | |
1262 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1263 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1264 | ||
67d874c3 VK |
1265 | dev_pm_qos_remove_notifier(dev, &policy->nb_max, |
1266 | DEV_PM_QOS_MAX_FREQUENCY); | |
1267 | dev_pm_qos_remove_notifier(dev, &policy->nb_min, | |
1268 | DEV_PM_QOS_MIN_FREQUENCY); | |
6a149036 VK |
1269 | |
1270 | if (policy->max_freq_req) { | |
1271 | /* | |
1272 | * CPUFREQ_CREATE_POLICY notification is sent only after | |
1273 | * successfully adding max_freq_req request. | |
1274 | */ | |
1275 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1276 | CPUFREQ_REMOVE_POLICY, policy); | |
1277 | dev_pm_qos_remove_request(policy->max_freq_req); | |
1278 | } | |
1279 | ||
18c49926 VK |
1280 | dev_pm_qos_remove_request(policy->min_freq_req); |
1281 | kfree(policy->min_freq_req); | |
67d874c3 | 1282 | |
f9f41e3e | 1283 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1284 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1285 | free_cpumask_var(policy->related_cpus); |
1286 | free_cpumask_var(policy->cpus); | |
1287 | kfree(policy); | |
1288 | } | |
1289 | ||
0b275352 | 1290 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1291 | { |
7f0c020a | 1292 | struct cpufreq_policy *policy; |
194d99c7 | 1293 | bool new_policy; |
1da177e4 | 1294 | unsigned long flags; |
0b275352 RW |
1295 | unsigned int j; |
1296 | int ret; | |
87549141 | 1297 | |
0b275352 | 1298 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1299 | |
bb29ae15 | 1300 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1301 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1302 | if (policy) { |
9104bb26 | 1303 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1304 | if (!policy_is_inactive(policy)) |
d9612a49 | 1305 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1306 | |
11ce707e | 1307 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1308 | new_policy = false; |
11ce707e RW |
1309 | down_write(&policy->rwsem); |
1310 | policy->cpu = cpu; | |
1311 | policy->governor = NULL; | |
1312 | up_write(&policy->rwsem); | |
1313 | } else { | |
194d99c7 | 1314 | new_policy = true; |
a34e63b1 | 1315 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1316 | if (!policy) |
d4d854d6 | 1317 | return -ENOMEM; |
72368d12 | 1318 | } |
0d66b91e | 1319 | |
91a12e91 VK |
1320 | if (!new_policy && cpufreq_driver->online) { |
1321 | ret = cpufreq_driver->online(policy); | |
1322 | if (ret) { | |
1323 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1324 | __LINE__); | |
1325 | goto out_exit_policy; | |
1326 | } | |
1da177e4 | 1327 | |
91a12e91 VK |
1328 | /* Recover policy->cpus using related_cpus */ |
1329 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1330 | } else { | |
1331 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1332 | |
91a12e91 VK |
1333 | /* |
1334 | * Call driver. From then on the cpufreq must be able | |
1335 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1336 | */ | |
1337 | ret = cpufreq_driver->init(policy); | |
1338 | if (ret) { | |
1339 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1340 | __LINE__); | |
1341 | goto out_free_policy; | |
1342 | } | |
d417e069 | 1343 | |
91a12e91 VK |
1344 | ret = cpufreq_table_validate_and_sort(policy); |
1345 | if (ret) | |
1346 | goto out_exit_policy; | |
6d4e81ed | 1347 | |
4d1f3a5b | 1348 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1349 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1350 | } |
559ed407 | 1351 | |
91a12e91 | 1352 | down_write(&policy->rwsem); |
5a7e56a5 VK |
1353 | /* |
1354 | * affected cpus must always be the one, which are online. We aren't | |
1355 | * managing offline cpus here. | |
1356 | */ | |
1357 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1358 | ||
194d99c7 | 1359 | if (new_policy) { |
18c49926 | 1360 | struct device *dev = get_cpu_device(cpu); |
6d4e81ed | 1361 | |
2f0ba790 | 1362 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1363 | per_cpu(cpufreq_cpu_data, j) = policy; |
2f0ba790 RW |
1364 | add_cpu_dev_symlink(policy, j); |
1365 | } | |
18c49926 VK |
1366 | |
1367 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1368 | GFP_KERNEL); | |
1369 | if (!policy->min_freq_req) | |
1370 | goto out_destroy_policy; | |
1371 | ||
1372 | ret = dev_pm_qos_add_request(dev, policy->min_freq_req, | |
1373 | DEV_PM_QOS_MIN_FREQUENCY, | |
1374 | policy->min); | |
1375 | if (ret < 0) { | |
1376 | /* | |
1377 | * So we don't call dev_pm_qos_remove_request() for an | |
1378 | * uninitialized request. | |
1379 | */ | |
1380 | kfree(policy->min_freq_req); | |
1381 | policy->min_freq_req = NULL; | |
1382 | ||
1383 | dev_err(dev, "Failed to add min-freq constraint (%d)\n", | |
1384 | ret); | |
1385 | goto out_destroy_policy; | |
1386 | } | |
1387 | ||
1388 | /* | |
1389 | * This must be initialized right here to avoid calling | |
1390 | * dev_pm_qos_remove_request() on uninitialized request in case | |
1391 | * of errors. | |
1392 | */ | |
1393 | policy->max_freq_req = policy->min_freq_req + 1; | |
1394 | ||
1395 | ret = dev_pm_qos_add_request(dev, policy->max_freq_req, | |
1396 | DEV_PM_QOS_MAX_FREQUENCY, | |
1397 | policy->max); | |
1398 | if (ret < 0) { | |
1399 | policy->max_freq_req = NULL; | |
1400 | dev_err(dev, "Failed to add max-freq constraint (%d)\n", | |
1401 | ret); | |
1402 | goto out_destroy_policy; | |
1403 | } | |
6a149036 VK |
1404 | |
1405 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1406 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1407 | } |
652ed95d | 1408 | |
5ddc6d4e | 1409 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1410 | policy->cur = cpufreq_driver->get(policy->cpu); |
1411 | if (!policy->cur) { | |
1412 | pr_err("%s: ->get() failed\n", __func__); | |
d417e069 | 1413 | goto out_destroy_policy; |
da60ce9f VK |
1414 | } |
1415 | } | |
1416 | ||
d3916691 VK |
1417 | /* |
1418 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1419 | * frequency table present with cpufreq core. In such cases CPU might be | |
1420 | * unstable if it has to run on that frequency for long duration of time | |
1421 | * and so its better to set it to a frequency which is specified in | |
1422 | * freq-table. This also makes cpufreq stats inconsistent as | |
1423 | * cpufreq-stats would fail to register because current frequency of CPU | |
1424 | * isn't found in freq-table. | |
1425 | * | |
1426 | * Because we don't want this change to effect boot process badly, we go | |
1427 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1428 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1429 | * is initialized to zero). | |
1430 | * | |
1431 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1432 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1433 | * equal to target-freq. | |
1434 | */ | |
1435 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1436 | && has_target()) { | |
1437 | /* Are we running at unknown frequency ? */ | |
1438 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1439 | if (ret == -EINVAL) { | |
1440 | /* Warn user and fix it */ | |
1441 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1442 | __func__, policy->cpu, policy->cur); | |
1443 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1444 | CPUFREQ_RELATION_L); | |
1445 | ||
1446 | /* | |
1447 | * Reaching here after boot in a few seconds may not | |
1448 | * mean that system will remain stable at "unknown" | |
1449 | * frequency for longer duration. Hence, a BUG_ON(). | |
1450 | */ | |
1451 | BUG_ON(ret); | |
1452 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1453 | __func__, policy->cpu, policy->cur); | |
1454 | } | |
1455 | } | |
1456 | ||
194d99c7 | 1457 | if (new_policy) { |
d9612a49 | 1458 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1459 | if (ret) |
d417e069 | 1460 | goto out_destroy_policy; |
1aefc75b RW |
1461 | |
1462 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1463 | |
988bed09 VK |
1464 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1465 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1466 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1467 | } | |
9515f4d6 | 1468 | |
7f0fa40f VK |
1469 | ret = cpufreq_init_policy(policy); |
1470 | if (ret) { | |
1471 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1472 | __func__, cpu, ret); | |
d417e069 | 1473 | goto out_destroy_policy; |
08fd8c1c | 1474 | } |
e18f1682 | 1475 | |
4e97b631 | 1476 | up_write(&policy->rwsem); |
08fd8c1c | 1477 | |
038c5b3e | 1478 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1479 | |
7c45cf31 VK |
1480 | /* Callback for handling stuff after policy is ready */ |
1481 | if (cpufreq_driver->ready) | |
1482 | cpufreq_driver->ready(policy); | |
1483 | ||
bcc61569 | 1484 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1485 | policy->cdev = of_cpufreq_cooling_register(policy); |
1486 | ||
2d06d8c4 | 1487 | pr_debug("initialization complete\n"); |
87c32271 | 1488 | |
1da177e4 LT |
1489 | return 0; |
1490 | ||
d417e069 | 1491 | out_destroy_policy: |
b24b6478 VK |
1492 | for_each_cpu(j, policy->real_cpus) |
1493 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1494 | ||
7106e02b PB |
1495 | up_write(&policy->rwsem); |
1496 | ||
d417e069 | 1497 | out_exit_policy: |
da60ce9f VK |
1498 | if (cpufreq_driver->exit) |
1499 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1500 | |
8101f997 | 1501 | out_free_policy: |
f9f41e3e | 1502 | cpufreq_policy_free(policy); |
1da177e4 LT |
1503 | return ret; |
1504 | } | |
1505 | ||
0b275352 RW |
1506 | /** |
1507 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1508 | * @dev: CPU device. | |
1509 | * @sif: Subsystem interface structure pointer (not used) | |
1510 | */ | |
1511 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1512 | { | |
a794d613 | 1513 | struct cpufreq_policy *policy; |
0b275352 | 1514 | unsigned cpu = dev->id; |
26619804 | 1515 | int ret; |
0b275352 RW |
1516 | |
1517 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1518 | ||
26619804 VK |
1519 | if (cpu_online(cpu)) { |
1520 | ret = cpufreq_online(cpu); | |
1521 | if (ret) | |
1522 | return ret; | |
1523 | } | |
0b275352 | 1524 | |
26619804 | 1525 | /* Create sysfs link on CPU registration */ |
a794d613 | 1526 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 RW |
1527 | if (policy) |
1528 | add_cpu_dev_symlink(policy, cpu); | |
26619804 | 1529 | |
2f0ba790 | 1530 | return 0; |
1da177e4 LT |
1531 | } |
1532 | ||
27622b06 | 1533 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1534 | { |
3a3e9e06 | 1535 | struct cpufreq_policy *policy; |
69cee714 | 1536 | int ret; |
1da177e4 | 1537 | |
b8eed8af | 1538 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1539 | |
988bed09 | 1540 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1541 | if (!policy) { |
b8eed8af | 1542 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1543 | return 0; |
1da177e4 | 1544 | } |
1da177e4 | 1545 | |
49f18560 | 1546 | down_write(&policy->rwsem); |
45482c70 RW |
1547 | if (has_target()) |
1548 | cpufreq_stop_governor(policy); | |
1da177e4 | 1549 | |
9591becb | 1550 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1551 | |
9591becb VK |
1552 | if (policy_is_inactive(policy)) { |
1553 | if (has_target()) | |
1554 | strncpy(policy->last_governor, policy->governor->name, | |
1555 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1556 | else |
1557 | policy->last_policy = policy->policy; | |
9591becb VK |
1558 | } else if (cpu == policy->cpu) { |
1559 | /* Nominate new CPU */ | |
1560 | policy->cpu = cpumask_any(policy->cpus); | |
1561 | } | |
084f3493 | 1562 | |
9591becb VK |
1563 | /* Start governor again for active policy */ |
1564 | if (!policy_is_inactive(policy)) { | |
1565 | if (has_target()) { | |
0a300767 | 1566 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1567 | if (ret) |
1568 | pr_err("%s: Failed to start governor\n", __func__); | |
1569 | } | |
cedb70af | 1570 | |
49f18560 | 1571 | goto unlock; |
cedb70af SB |
1572 | } |
1573 | ||
bcc61569 | 1574 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1575 | cpufreq_cooling_unregister(policy->cdev); |
1576 | policy->cdev = NULL; | |
1577 | } | |
1578 | ||
69cee714 VK |
1579 | if (cpufreq_driver->stop_cpu) |
1580 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1581 | |
36be3418 RW |
1582 | if (has_target()) |
1583 | cpufreq_exit_governor(policy); | |
1da177e4 | 1584 | |
87549141 | 1585 | /* |
91a12e91 VK |
1586 | * Perform the ->offline() during light-weight tear-down, as |
1587 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1588 | */ |
91a12e91 VK |
1589 | if (cpufreq_driver->offline) { |
1590 | cpufreq_driver->offline(policy); | |
1591 | } else if (cpufreq_driver->exit) { | |
87549141 | 1592 | cpufreq_driver->exit(policy); |
55582bcc SP |
1593 | policy->freq_table = NULL; |
1594 | } | |
49f18560 VK |
1595 | |
1596 | unlock: | |
1597 | up_write(&policy->rwsem); | |
27622b06 | 1598 | return 0; |
1da177e4 LT |
1599 | } |
1600 | ||
cedb70af | 1601 | /** |
27a862e9 | 1602 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1603 | * |
1604 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1605 | */ |
71db87ba | 1606 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1607 | { |
8a25a2fd | 1608 | unsigned int cpu = dev->id; |
559ed407 | 1609 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1610 | |
559ed407 | 1611 | if (!policy) |
1af115d6 | 1612 | return; |
87549141 | 1613 | |
69cee714 VK |
1614 | if (cpu_online(cpu)) |
1615 | cpufreq_offline(cpu); | |
87549141 | 1616 | |
559ed407 | 1617 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1618 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1619 | |
91a12e91 VK |
1620 | if (cpumask_empty(policy->real_cpus)) { |
1621 | /* We did light-weight exit earlier, do full tear down now */ | |
1622 | if (cpufreq_driver->offline) | |
1623 | cpufreq_driver->exit(policy); | |
1624 | ||
f9f41e3e | 1625 | cpufreq_policy_free(policy); |
91a12e91 | 1626 | } |
5a01f2e8 VP |
1627 | } |
1628 | ||
1da177e4 | 1629 | /** |
bb176f7d VK |
1630 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1631 | * in deep trouble. | |
a1e1dc41 | 1632 | * @policy: policy managing CPUs |
1da177e4 LT |
1633 | * @new_freq: CPU frequency the CPU actually runs at |
1634 | * | |
29464f28 DJ |
1635 | * We adjust to current frequency first, and need to clean up later. |
1636 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1637 | */ |
a1e1dc41 | 1638 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1639 | unsigned int new_freq) |
1da177e4 LT |
1640 | { |
1641 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1642 | |
e837f9b5 | 1643 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1644 | policy->cur, new_freq); |
1da177e4 | 1645 | |
a1e1dc41 | 1646 | freqs.old = policy->cur; |
1da177e4 | 1647 | freqs.new = new_freq; |
b43a7ffb | 1648 | |
8fec051e VK |
1649 | cpufreq_freq_transition_begin(policy, &freqs); |
1650 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1651 | } |
1652 | ||
5980752e VK |
1653 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1654 | { | |
1655 | unsigned int new_freq; | |
1656 | ||
1657 | new_freq = cpufreq_driver->get(policy->cpu); | |
1658 | if (!new_freq) | |
1659 | return 0; | |
1660 | ||
1661 | /* | |
1662 | * If fast frequency switching is used with the given policy, the check | |
1663 | * against policy->cur is pointless, so skip it in that case. | |
1664 | */ | |
1665 | if (policy->fast_switch_enabled || !has_target()) | |
1666 | return new_freq; | |
1667 | ||
1668 | if (policy->cur != new_freq) { | |
1669 | cpufreq_out_of_sync(policy, new_freq); | |
1670 | if (update) | |
1671 | schedule_work(&policy->update); | |
1672 | } | |
1673 | ||
1674 | return new_freq; | |
1675 | } | |
1676 | ||
32ee8c3e | 1677 | /** |
4ab70df4 | 1678 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1679 | * @cpu: CPU number |
1680 | * | |
1681 | * This is the last known freq, without actually getting it from the driver. | |
1682 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1683 | */ | |
1684 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1685 | { | |
9e21ba8b | 1686 | struct cpufreq_policy *policy; |
e08f5f5b | 1687 | unsigned int ret_freq = 0; |
c75361c0 | 1688 | unsigned long flags; |
95235ca2 | 1689 | |
c75361c0 RC |
1690 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1691 | ||
1692 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1693 | ret_freq = cpufreq_driver->get(cpu); | |
1694 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1695 | return ret_freq; | |
1696 | } | |
1697 | ||
1698 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1699 | |
1700 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1701 | if (policy) { |
e08f5f5b | 1702 | ret_freq = policy->cur; |
95235ca2 VP |
1703 | cpufreq_cpu_put(policy); |
1704 | } | |
1705 | ||
4d34a67d | 1706 | return ret_freq; |
95235ca2 VP |
1707 | } |
1708 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1709 | ||
3d737108 JB |
1710 | /** |
1711 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1712 | * @cpu: CPU number | |
1713 | * | |
1714 | * Just return the max possible frequency for a given CPU. | |
1715 | */ | |
1716 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1717 | { | |
1718 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1719 | unsigned int ret_freq = 0; | |
1720 | ||
1721 | if (policy) { | |
1722 | ret_freq = policy->max; | |
1723 | cpufreq_cpu_put(policy); | |
1724 | } | |
1725 | ||
1726 | return ret_freq; | |
1727 | } | |
1728 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1729 | ||
d92d50a4 | 1730 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1731 | { |
4db7c34c | 1732 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1733 | return 0; |
1da177e4 | 1734 | |
5980752e | 1735 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1736 | } |
1da177e4 | 1737 | |
5a01f2e8 VP |
1738 | /** |
1739 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1740 | * @cpu: CPU number | |
1741 | * | |
1742 | * Get the CPU current (static) CPU frequency | |
1743 | */ | |
1744 | unsigned int cpufreq_get(unsigned int cpu) | |
1745 | { | |
999976e0 | 1746 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1747 | unsigned int ret_freq = 0; |
5a01f2e8 | 1748 | |
999976e0 AP |
1749 | if (policy) { |
1750 | down_read(&policy->rwsem); | |
4db7c34c YH |
1751 | if (cpufreq_driver->get) |
1752 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1753 | up_read(&policy->rwsem); |
5a01f2e8 | 1754 | |
999976e0 AP |
1755 | cpufreq_cpu_put(policy); |
1756 | } | |
6eed9404 | 1757 | |
4d34a67d | 1758 | return ret_freq; |
1da177e4 LT |
1759 | } |
1760 | EXPORT_SYMBOL(cpufreq_get); | |
1761 | ||
8a25a2fd KS |
1762 | static struct subsys_interface cpufreq_interface = { |
1763 | .name = "cpufreq", | |
1764 | .subsys = &cpu_subsys, | |
1765 | .add_dev = cpufreq_add_dev, | |
1766 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1767 | }; |
1768 | ||
e28867ea VK |
1769 | /* |
1770 | * In case platform wants some specific frequency to be configured | |
1771 | * during suspend.. | |
1772 | */ | |
1773 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1774 | { | |
1775 | int ret; | |
1776 | ||
1777 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1778 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1779 | return 0; | |
e28867ea VK |
1780 | } |
1781 | ||
1782 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1783 | policy->suspend_freq); | |
1784 | ||
1785 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1786 | CPUFREQ_RELATION_H); | |
1787 | if (ret) | |
1788 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1789 | __func__, policy->suspend_freq, ret); | |
1790 | ||
1791 | return ret; | |
1792 | } | |
1793 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1794 | ||
42d4dc3f | 1795 | /** |
2f0aea93 | 1796 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1797 | * |
2f0aea93 VK |
1798 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1799 | * as some platforms can't change frequency after this point in suspend cycle. | |
1800 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1801 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1802 | */ |
2f0aea93 | 1803 | void cpufreq_suspend(void) |
42d4dc3f | 1804 | { |
3a3e9e06 | 1805 | struct cpufreq_policy *policy; |
42d4dc3f | 1806 | |
2f0aea93 VK |
1807 | if (!cpufreq_driver) |
1808 | return; | |
42d4dc3f | 1809 | |
ba41e1bc | 1810 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1811 | goto suspend; |
42d4dc3f | 1812 | |
2f0aea93 VK |
1813 | pr_debug("%s: Suspending Governors\n", __func__); |
1814 | ||
f963735a | 1815 | for_each_active_policy(policy) { |
ba41e1bc RW |
1816 | if (has_target()) { |
1817 | down_write(&policy->rwsem); | |
45482c70 | 1818 | cpufreq_stop_governor(policy); |
ba41e1bc | 1819 | up_write(&policy->rwsem); |
ba41e1bc RW |
1820 | } |
1821 | ||
1822 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1823 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1824 | cpufreq_driver->name); | |
42d4dc3f | 1825 | } |
b1b12bab VK |
1826 | |
1827 | suspend: | |
1828 | cpufreq_suspended = true; | |
42d4dc3f BH |
1829 | } |
1830 | ||
1da177e4 | 1831 | /** |
2f0aea93 | 1832 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1833 | * |
2f0aea93 VK |
1834 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1835 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1836 | */ |
2f0aea93 | 1837 | void cpufreq_resume(void) |
1da177e4 | 1838 | { |
3a3e9e06 | 1839 | struct cpufreq_policy *policy; |
49f18560 | 1840 | int ret; |
1da177e4 | 1841 | |
2f0aea93 | 1842 | if (!cpufreq_driver) |
703cbaa6 BY |
1843 | return; |
1844 | ||
1845 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1846 | return; |
1da177e4 | 1847 | |
8e30444e LT |
1848 | cpufreq_suspended = false; |
1849 | ||
ba41e1bc | 1850 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1851 | return; |
1da177e4 | 1852 | |
2f0aea93 | 1853 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1854 | |
f963735a | 1855 | for_each_active_policy(policy) { |
49f18560 | 1856 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1857 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1858 | policy); | |
ba41e1bc | 1859 | } else if (has_target()) { |
49f18560 | 1860 | down_write(&policy->rwsem); |
0a300767 | 1861 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1862 | up_write(&policy->rwsem); |
1863 | ||
1864 | if (ret) | |
1865 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1866 | __func__, policy); | |
1867 | } | |
2f0aea93 VK |
1868 | } |
1869 | } | |
1da177e4 | 1870 | |
9d95046e BP |
1871 | /** |
1872 | * cpufreq_get_current_driver - return current driver's name | |
1873 | * | |
1874 | * Return the name string of the currently loaded cpufreq driver | |
1875 | * or NULL, if none. | |
1876 | */ | |
1877 | const char *cpufreq_get_current_driver(void) | |
1878 | { | |
1c3d85dd RW |
1879 | if (cpufreq_driver) |
1880 | return cpufreq_driver->name; | |
1881 | ||
1882 | return NULL; | |
9d95046e BP |
1883 | } |
1884 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1885 | |
51315cdf TP |
1886 | /** |
1887 | * cpufreq_get_driver_data - return current driver data | |
1888 | * | |
1889 | * Return the private data of the currently loaded cpufreq | |
1890 | * driver, or NULL if no cpufreq driver is loaded. | |
1891 | */ | |
1892 | void *cpufreq_get_driver_data(void) | |
1893 | { | |
1894 | if (cpufreq_driver) | |
1895 | return cpufreq_driver->driver_data; | |
1896 | ||
1897 | return NULL; | |
1898 | } | |
1899 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1900 | ||
1da177e4 LT |
1901 | /********************************************************************* |
1902 | * NOTIFIER LISTS INTERFACE * | |
1903 | *********************************************************************/ | |
1904 | ||
1905 | /** | |
1906 | * cpufreq_register_notifier - register a driver with cpufreq | |
1907 | * @nb: notifier function to register | |
1908 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1909 | * | |
32ee8c3e | 1910 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1911 | * are notified about clock rate changes (once before and once after |
1912 | * the transition), or a list of drivers that are notified about | |
1913 | * changes in cpufreq policy. | |
1914 | * | |
1915 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1916 | * blocking_notifier_chain_register. |
1da177e4 LT |
1917 | */ |
1918 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1919 | { | |
1920 | int ret; | |
1921 | ||
d5aaffa9 DB |
1922 | if (cpufreq_disabled()) |
1923 | return -EINVAL; | |
1924 | ||
1da177e4 LT |
1925 | switch (list) { |
1926 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1927 | mutex_lock(&cpufreq_fast_switch_lock); |
1928 | ||
1929 | if (cpufreq_fast_switch_count > 0) { | |
1930 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1931 | return -EBUSY; | |
1932 | } | |
b4dfdbb3 | 1933 | ret = srcu_notifier_chain_register( |
e041c683 | 1934 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1935 | if (!ret) |
1936 | cpufreq_fast_switch_count--; | |
1937 | ||
1938 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1939 | break; |
1940 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1941 | ret = blocking_notifier_chain_register( |
1942 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1943 | break; |
1944 | default: | |
1945 | ret = -EINVAL; | |
1946 | } | |
1da177e4 LT |
1947 | |
1948 | return ret; | |
1949 | } | |
1950 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1951 | ||
1da177e4 LT |
1952 | /** |
1953 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1954 | * @nb: notifier block to be unregistered | |
bb176f7d | 1955 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1956 | * |
1957 | * Remove a driver from the CPU frequency notifier list. | |
1958 | * | |
1959 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1960 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1961 | */ |
1962 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1963 | { | |
1964 | int ret; | |
1965 | ||
d5aaffa9 DB |
1966 | if (cpufreq_disabled()) |
1967 | return -EINVAL; | |
1968 | ||
1da177e4 LT |
1969 | switch (list) { |
1970 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1971 | mutex_lock(&cpufreq_fast_switch_lock); |
1972 | ||
b4dfdbb3 | 1973 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1974 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1975 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
1976 | cpufreq_fast_switch_count++; | |
1977 | ||
1978 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1979 | break; |
1980 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1981 | ret = blocking_notifier_chain_unregister( |
1982 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1983 | break; |
1984 | default: | |
1985 | ret = -EINVAL; | |
1986 | } | |
1da177e4 LT |
1987 | |
1988 | return ret; | |
1989 | } | |
1990 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1991 | ||
1992 | ||
1993 | /********************************************************************* | |
1994 | * GOVERNORS * | |
1995 | *********************************************************************/ | |
1996 | ||
b7898fda RW |
1997 | /** |
1998 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
1999 | * @policy: cpufreq policy to switch the frequency for. | |
2000 | * @target_freq: New frequency to set (may be approximate). | |
2001 | * | |
2002 | * Carry out a fast frequency switch without sleeping. | |
2003 | * | |
2004 | * The driver's ->fast_switch() callback invoked by this function must be | |
2005 | * suitable for being called from within RCU-sched read-side critical sections | |
2006 | * and it is expected to select the minimum available frequency greater than or | |
2007 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2008 | * | |
2009 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2010 | * | |
2011 | * Governors calling this function must guarantee that it will never be invoked | |
2012 | * twice in parallel for the same policy and that it will never be called in | |
2013 | * parallel with either ->target() or ->target_index() for the same policy. | |
2014 | * | |
209887e6 VK |
2015 | * Returns the actual frequency set for the CPU. |
2016 | * | |
2017 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2018 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2019 | */ |
2020 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2021 | unsigned int target_freq) | |
2022 | { | |
b9af6948 | 2023 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
b7898fda RW |
2024 | |
2025 | return cpufreq_driver->fast_switch(policy, target_freq); | |
2026 | } | |
2027 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2028 | ||
1c03a2d0 VK |
2029 | /* Must set freqs->new to intermediate frequency */ |
2030 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2031 | struct cpufreq_freqs *freqs, int index) | |
2032 | { | |
2033 | int ret; | |
2034 | ||
2035 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2036 | ||
2037 | /* We don't need to switch to intermediate freq */ | |
2038 | if (!freqs->new) | |
2039 | return 0; | |
2040 | ||
2041 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2042 | __func__, policy->cpu, freqs->old, freqs->new); | |
2043 | ||
2044 | cpufreq_freq_transition_begin(policy, freqs); | |
2045 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2046 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2047 | ||
2048 | if (ret) | |
2049 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2050 | __func__, ret); | |
2051 | ||
2052 | return ret; | |
2053 | } | |
2054 | ||
23727845 | 2055 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2056 | { |
1c03a2d0 VK |
2057 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
2058 | unsigned int intermediate_freq = 0; | |
23727845 | 2059 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2060 | int retval = -EINVAL; |
2061 | bool notify; | |
2062 | ||
23727845 VK |
2063 | if (newfreq == policy->cur) |
2064 | return 0; | |
2065 | ||
8d65775d | 2066 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2067 | if (notify) { |
1c03a2d0 VK |
2068 | /* Handle switching to intermediate frequency */ |
2069 | if (cpufreq_driver->get_intermediate) { | |
2070 | retval = __target_intermediate(policy, &freqs, index); | |
2071 | if (retval) | |
2072 | return retval; | |
2073 | ||
2074 | intermediate_freq = freqs.new; | |
2075 | /* Set old freq to intermediate */ | |
2076 | if (intermediate_freq) | |
2077 | freqs.old = freqs.new; | |
2078 | } | |
8d65775d | 2079 | |
23727845 | 2080 | freqs.new = newfreq; |
8d65775d VK |
2081 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2082 | __func__, policy->cpu, freqs.old, freqs.new); | |
2083 | ||
2084 | cpufreq_freq_transition_begin(policy, &freqs); | |
2085 | } | |
2086 | ||
2087 | retval = cpufreq_driver->target_index(policy, index); | |
2088 | if (retval) | |
2089 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2090 | retval); | |
2091 | ||
1c03a2d0 | 2092 | if (notify) { |
8d65775d VK |
2093 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2094 | ||
1c03a2d0 VK |
2095 | /* |
2096 | * Failed after setting to intermediate freq? Driver should have | |
2097 | * reverted back to initial frequency and so should we. Check | |
2098 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2099 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2100 | */ |
2101 | if (unlikely(retval && intermediate_freq)) { | |
2102 | freqs.old = intermediate_freq; | |
2103 | freqs.new = policy->restore_freq; | |
2104 | cpufreq_freq_transition_begin(policy, &freqs); | |
2105 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2106 | } | |
2107 | } | |
2108 | ||
8d65775d VK |
2109 | return retval; |
2110 | } | |
2111 | ||
1da177e4 LT |
2112 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2113 | unsigned int target_freq, | |
2114 | unsigned int relation) | |
2115 | { | |
7249924e | 2116 | unsigned int old_target_freq = target_freq; |
d218ed77 | 2117 | int index; |
c32b6b8e | 2118 | |
a7b422cd KRW |
2119 | if (cpufreq_disabled()) |
2120 | return -ENODEV; | |
2121 | ||
7249924e | 2122 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 2123 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
2124 | |
2125 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2126 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2127 | |
9c0ebcf7 VK |
2128 | /* |
2129 | * This might look like a redundant call as we are checking it again | |
2130 | * after finding index. But it is left intentionally for cases where | |
2131 | * exactly same freq is called again and so we can save on few function | |
2132 | * calls. | |
2133 | */ | |
5a1c0228 VK |
2134 | if (target_freq == policy->cur) |
2135 | return 0; | |
2136 | ||
1c03a2d0 VK |
2137 | /* Save last value to restore later on errors */ |
2138 | policy->restore_freq = policy->cur; | |
2139 | ||
1c3d85dd | 2140 | if (cpufreq_driver->target) |
6019d23a | 2141 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 2142 | |
6019d23a RW |
2143 | if (!cpufreq_driver->target_index) |
2144 | return -EINVAL; | |
9c0ebcf7 | 2145 | |
d218ed77 | 2146 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 2147 | |
23727845 | 2148 | return __target_index(policy, index); |
1da177e4 LT |
2149 | } |
2150 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2151 | ||
1da177e4 LT |
2152 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2153 | unsigned int target_freq, | |
2154 | unsigned int relation) | |
2155 | { | |
62c23a89 | 2156 | int ret; |
1da177e4 | 2157 | |
ad7722da | 2158 | down_write(&policy->rwsem); |
1da177e4 LT |
2159 | |
2160 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2161 | ||
ad7722da | 2162 | up_write(&policy->rwsem); |
1da177e4 | 2163 | |
1da177e4 LT |
2164 | return ret; |
2165 | } | |
2166 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2167 | ||
de1df26b RW |
2168 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2169 | { | |
2170 | return NULL; | |
2171 | } | |
2172 | ||
a92604b4 | 2173 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2174 | { |
cc993cab | 2175 | int ret; |
6afde10c | 2176 | |
2f0aea93 VK |
2177 | /* Don't start any governor operations if we are entering suspend */ |
2178 | if (cpufreq_suspended) | |
2179 | return 0; | |
cb57720b EZ |
2180 | /* |
2181 | * Governor might not be initiated here if ACPI _PPC changed | |
2182 | * notification happened, so check it. | |
2183 | */ | |
2184 | if (!policy->governor) | |
2185 | return -EINVAL; | |
2f0aea93 | 2186 | |
ed4676e2 VK |
2187 | /* Platform doesn't want dynamic frequency switching ? */ |
2188 | if (policy->governor->dynamic_switching && | |
fc4c709f | 2189 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2190 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2191 | ||
2192 | if (gov) { | |
fe829ed8 | 2193 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2194 | policy->governor->name, gov->name); |
6afde10c | 2195 | policy->governor = gov; |
de1df26b RW |
2196 | } else { |
2197 | return -EINVAL; | |
6afde10c | 2198 | } |
1c256245 | 2199 | } |
1da177e4 | 2200 | |
a92604b4 RW |
2201 | if (!try_module_get(policy->governor->owner)) |
2202 | return -EINVAL; | |
95731ebb | 2203 | |
a92604b4 | 2204 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2205 | |
e788892b RW |
2206 | if (policy->governor->init) { |
2207 | ret = policy->governor->init(policy); | |
2208 | if (ret) { | |
36be3418 | 2209 | module_put(policy->governor->owner); |
e788892b RW |
2210 | return ret; |
2211 | } | |
36be3418 | 2212 | } |
1da177e4 | 2213 | |
a92604b4 RW |
2214 | return 0; |
2215 | } | |
2216 | ||
2217 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2218 | { | |
2219 | if (cpufreq_suspended || !policy->governor) | |
2220 | return; | |
2221 | ||
2222 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2223 | ||
e788892b RW |
2224 | if (policy->governor->exit) |
2225 | policy->governor->exit(policy); | |
a92604b4 | 2226 | |
a92604b4 | 2227 | module_put(policy->governor->owner); |
1da177e4 LT |
2228 | } |
2229 | ||
0a300767 RW |
2230 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
2231 | { | |
2232 | int ret; | |
2233 | ||
a92604b4 RW |
2234 | if (cpufreq_suspended) |
2235 | return 0; | |
2236 | ||
2237 | if (!policy->governor) | |
2238 | return -EINVAL; | |
2239 | ||
2240 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2241 | ||
407d0fff | 2242 | if (cpufreq_driver->get) |
5980752e | 2243 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2244 | |
e788892b RW |
2245 | if (policy->governor->start) { |
2246 | ret = policy->governor->start(policy); | |
2247 | if (ret) | |
2248 | return ret; | |
2249 | } | |
2250 | ||
2251 | if (policy->governor->limits) | |
2252 | policy->governor->limits(policy); | |
d6ff44d6 | 2253 | |
d6ff44d6 | 2254 | return 0; |
0a300767 RW |
2255 | } |
2256 | ||
a92604b4 RW |
2257 | static void cpufreq_stop_governor(struct cpufreq_policy *policy) |
2258 | { | |
2259 | if (cpufreq_suspended || !policy->governor) | |
2260 | return; | |
2261 | ||
2262 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2263 | ||
e788892b RW |
2264 | if (policy->governor->stop) |
2265 | policy->governor->stop(policy); | |
a92604b4 RW |
2266 | } |
2267 | ||
2268 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2269 | { | |
2270 | if (cpufreq_suspended || !policy->governor) | |
2271 | return; | |
2272 | ||
2273 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2274 | ||
e788892b RW |
2275 | if (policy->governor->limits) |
2276 | policy->governor->limits(policy); | |
0a300767 RW |
2277 | } |
2278 | ||
1da177e4 LT |
2279 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2280 | { | |
3bcb09a3 | 2281 | int err; |
1da177e4 LT |
2282 | |
2283 | if (!governor) | |
2284 | return -EINVAL; | |
2285 | ||
a7b422cd KRW |
2286 | if (cpufreq_disabled()) |
2287 | return -ENODEV; | |
2288 | ||
3fc54d37 | 2289 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2290 | |
3bcb09a3 | 2291 | err = -EBUSY; |
42f91fa1 | 2292 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2293 | err = 0; |
2294 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2295 | } |
1da177e4 | 2296 | |
32ee8c3e | 2297 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2298 | return err; |
1da177e4 LT |
2299 | } |
2300 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2301 | ||
1da177e4 LT |
2302 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2303 | { | |
4573237b VK |
2304 | struct cpufreq_policy *policy; |
2305 | unsigned long flags; | |
90e41bac | 2306 | |
1da177e4 LT |
2307 | if (!governor) |
2308 | return; | |
2309 | ||
a7b422cd KRW |
2310 | if (cpufreq_disabled()) |
2311 | return; | |
2312 | ||
4573237b VK |
2313 | /* clear last_governor for all inactive policies */ |
2314 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2315 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2316 | if (!strcmp(policy->last_governor, governor->name)) { |
2317 | policy->governor = NULL; | |
4573237b | 2318 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2319 | } |
90e41bac | 2320 | } |
4573237b | 2321 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2322 | |
3fc54d37 | 2323 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2324 | list_del(&governor->governor_list); |
3fc54d37 | 2325 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2326 | } |
2327 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2328 | ||
2329 | ||
1da177e4 LT |
2330 | /********************************************************************* |
2331 | * POLICY INTERFACE * | |
2332 | *********************************************************************/ | |
2333 | ||
2334 | /** | |
2335 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2336 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2337 | * is written | |
1da177e4 LT |
2338 | * |
2339 | * Reads the current cpufreq policy. | |
2340 | */ | |
2341 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2342 | { | |
2343 | struct cpufreq_policy *cpu_policy; | |
2344 | if (!policy) | |
2345 | return -EINVAL; | |
2346 | ||
2347 | cpu_policy = cpufreq_cpu_get(cpu); | |
2348 | if (!cpu_policy) | |
2349 | return -EINVAL; | |
2350 | ||
d5b73cd8 | 2351 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2352 | |
2353 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2354 | return 0; |
2355 | } | |
2356 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2357 | ||
a0dbb819 RW |
2358 | /** |
2359 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2360 | * @policy: Policy object to modify. | |
2361 | * @new_policy: New policy data. | |
2362 | * | |
df0eea44 VK |
2363 | * Pass @new_policy to the cpufreq driver's ->verify() callback. Next, copy the |
2364 | * min and max parameters of @new_policy to @policy and either invoke the | |
2365 | * driver's ->setpolicy() callback (if present) or carry out a governor update | |
2366 | * for @policy. That is, run the current governor's ->limits() callback (if the | |
2367 | * governor field in @new_policy points to the same object as the one in | |
2368 | * @policy) or replace the governor for @policy with the new one stored in | |
2369 | * @new_policy. | |
a0dbb819 RW |
2370 | * |
2371 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2372 | */ |
9083e498 RW |
2373 | int cpufreq_set_policy(struct cpufreq_policy *policy, |
2374 | struct cpufreq_policy *new_policy) | |
1da177e4 | 2375 | { |
d9a789c7 | 2376 | struct cpufreq_governor *old_gov; |
67d874c3 | 2377 | struct device *cpu_dev = get_cpu_device(policy->cpu); |
d9a789c7 | 2378 | int ret; |
1da177e4 | 2379 | |
e837f9b5 JP |
2380 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2381 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2382 | |
d5b73cd8 | 2383 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2384 | |
fba9573b | 2385 | /* |
67d874c3 VK |
2386 | * PM QoS framework collects all the requests from users and provide us |
2387 | * the final aggregated value here. | |
2388 | */ | |
18c49926 VK |
2389 | new_policy->min = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MIN_FREQUENCY); |
2390 | new_policy->max = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MAX_FREQUENCY); | |
9c9a43ed | 2391 | |
1da177e4 | 2392 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2393 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2394 | if (ret) |
d9a789c7 | 2395 | return ret; |
1da177e4 | 2396 | |
3a3e9e06 VK |
2397 | policy->min = new_policy->min; |
2398 | policy->max = new_policy->max; | |
601b2185 | 2399 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2400 | |
e3c06236 SM |
2401 | policy->cached_target_freq = UINT_MAX; |
2402 | ||
2d06d8c4 | 2403 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2404 | policy->min, policy->max); |
1da177e4 | 2405 | |
1c3d85dd | 2406 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2407 | policy->policy = new_policy->policy; |
2d06d8c4 | 2408 | pr_debug("setting range\n"); |
167a38dc | 2409 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2410 | } |
1da177e4 | 2411 | |
0a300767 | 2412 | if (new_policy->governor == policy->governor) { |
2bb4059e | 2413 | pr_debug("governor limits update\n"); |
a92604b4 | 2414 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2415 | return 0; |
0a300767 | 2416 | } |
7bd353a9 | 2417 | |
d9a789c7 RW |
2418 | pr_debug("governor switch\n"); |
2419 | ||
2420 | /* save old, working values */ | |
2421 | old_gov = policy->governor; | |
2422 | /* end old governor */ | |
2423 | if (old_gov) { | |
45482c70 | 2424 | cpufreq_stop_governor(policy); |
36be3418 | 2425 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2426 | } |
2427 | ||
d9a789c7 RW |
2428 | /* start new governor */ |
2429 | policy->governor = new_policy->governor; | |
a92604b4 | 2430 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2431 | if (!ret) { |
0a300767 RW |
2432 | ret = cpufreq_start_governor(policy); |
2433 | if (!ret) { | |
2bb4059e | 2434 | pr_debug("governor change\n"); |
531b5c9f | 2435 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2436 | return 0; |
2437 | } | |
b7898fda | 2438 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2439 | } |
2440 | ||
2441 | /* new governor failed, so re-start old one */ | |
2442 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2443 | if (old_gov) { | |
2444 | policy->governor = old_gov; | |
a92604b4 | 2445 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2446 | policy->governor = NULL; |
2447 | else | |
0a300767 | 2448 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2449 | } |
2450 | ||
4bc384ae | 2451 | return ret; |
1da177e4 LT |
2452 | } |
2453 | ||
1da177e4 | 2454 | /** |
a0dbb819 RW |
2455 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2456 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2457 | * |
a0dbb819 | 2458 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2459 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2460 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2461 | * for the policy in question, among other things. | |
1da177e4 | 2462 | */ |
30248fef | 2463 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2464 | { |
540a3758 | 2465 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2466 | |
fefa8ff8 | 2467 | if (!policy) |
30248fef | 2468 | return; |
1da177e4 | 2469 | |
bb176f7d VK |
2470 | /* |
2471 | * BIOS might change freq behind our back | |
2472 | * -> ask driver for current freq and notify governors about a change | |
2473 | */ | |
5ddc6d4e | 2474 | if (cpufreq_driver->get && has_target() && |
5980752e | 2475 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2476 | goto unlock; |
30248fef | 2477 | |
70a59fde | 2478 | refresh_frequency_limits(policy); |
1da177e4 | 2479 | |
fefa8ff8 | 2480 | unlock: |
540a3758 | 2481 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2482 | } |
2483 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2484 | ||
5a25e3f7 RW |
2485 | /** |
2486 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2487 | * @cpu: CPU to update the policy limits for. | |
2488 | * | |
2489 | * Invoke the driver's ->update_limits callback if present or call | |
2490 | * cpufreq_update_policy() for @cpu. | |
2491 | */ | |
2492 | void cpufreq_update_limits(unsigned int cpu) | |
2493 | { | |
2494 | if (cpufreq_driver->update_limits) | |
2495 | cpufreq_driver->update_limits(cpu); | |
2496 | else | |
2497 | cpufreq_update_policy(cpu); | |
2498 | } | |
2499 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2500 | ||
6f19efc0 LM |
2501 | /********************************************************************* |
2502 | * BOOST * | |
2503 | *********************************************************************/ | |
2504 | static int cpufreq_boost_set_sw(int state) | |
2505 | { | |
6f19efc0 LM |
2506 | struct cpufreq_policy *policy; |
2507 | int ret = -EINVAL; | |
2508 | ||
f963735a | 2509 | for_each_active_policy(policy) { |
f8bfc116 VK |
2510 | if (!policy->freq_table) |
2511 | continue; | |
49f18560 | 2512 | |
f8bfc116 VK |
2513 | ret = cpufreq_frequency_table_cpuinfo(policy, |
2514 | policy->freq_table); | |
2515 | if (ret) { | |
2516 | pr_err("%s: Policy frequency update failed\n", | |
2517 | __func__); | |
2518 | break; | |
6f19efc0 | 2519 | } |
f8bfc116 | 2520 | |
18c49926 | 2521 | ret = dev_pm_qos_update_request(policy->max_freq_req, policy->max); |
e61a4125 | 2522 | if (ret < 0) |
18c49926 | 2523 | break; |
6f19efc0 LM |
2524 | } |
2525 | ||
2526 | return ret; | |
2527 | } | |
2528 | ||
2529 | int cpufreq_boost_trigger_state(int state) | |
2530 | { | |
2531 | unsigned long flags; | |
2532 | int ret = 0; | |
2533 | ||
2534 | if (cpufreq_driver->boost_enabled == state) | |
2535 | return 0; | |
2536 | ||
2537 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2538 | cpufreq_driver->boost_enabled = state; | |
2539 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2540 | ||
2541 | ret = cpufreq_driver->set_boost(state); | |
2542 | if (ret) { | |
2543 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2544 | cpufreq_driver->boost_enabled = !state; | |
2545 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2546 | ||
e837f9b5 JP |
2547 | pr_err("%s: Cannot %s BOOST\n", |
2548 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2549 | } |
2550 | ||
2551 | return ret; | |
2552 | } | |
2553 | ||
41669da0 | 2554 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2555 | { |
89f98d7e | 2556 | return cpufreq_driver->set_boost; |
6f19efc0 | 2557 | } |
6f19efc0 | 2558 | |
44139ed4 VK |
2559 | static int create_boost_sysfs_file(void) |
2560 | { | |
2561 | int ret; | |
2562 | ||
c82bd444 | 2563 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2564 | if (ret) |
2565 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2566 | __func__); | |
2567 | ||
2568 | return ret; | |
2569 | } | |
2570 | ||
2571 | static void remove_boost_sysfs_file(void) | |
2572 | { | |
2573 | if (cpufreq_boost_supported()) | |
c82bd444 | 2574 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2575 | } |
2576 | ||
2577 | int cpufreq_enable_boost_support(void) | |
2578 | { | |
2579 | if (!cpufreq_driver) | |
2580 | return -EINVAL; | |
2581 | ||
2582 | if (cpufreq_boost_supported()) | |
2583 | return 0; | |
2584 | ||
7a6c79f2 | 2585 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2586 | |
2587 | /* This will get removed on driver unregister */ | |
2588 | return create_boost_sysfs_file(); | |
2589 | } | |
2590 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2591 | ||
6f19efc0 LM |
2592 | int cpufreq_boost_enabled(void) |
2593 | { | |
2594 | return cpufreq_driver->boost_enabled; | |
2595 | } | |
2596 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2597 | ||
1da177e4 LT |
2598 | /********************************************************************* |
2599 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2600 | *********************************************************************/ | |
27622b06 | 2601 | static enum cpuhp_state hp_online; |
1da177e4 | 2602 | |
c4a3fa26 CY |
2603 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2604 | { | |
2605 | cpufreq_online(cpu); | |
2606 | ||
2607 | return 0; | |
2608 | } | |
2609 | ||
2610 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2611 | { | |
2612 | cpufreq_offline(cpu); | |
2613 | ||
2614 | return 0; | |
2615 | } | |
2616 | ||
1da177e4 LT |
2617 | /** |
2618 | * cpufreq_register_driver - register a CPU Frequency driver | |
2619 | * @driver_data: A struct cpufreq_driver containing the values# | |
2620 | * submitted by the CPU Frequency driver. | |
2621 | * | |
bb176f7d | 2622 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2623 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2624 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2625 | * |
2626 | */ | |
221dee28 | 2627 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2628 | { |
2629 | unsigned long flags; | |
2630 | int ret; | |
2631 | ||
a7b422cd KRW |
2632 | if (cpufreq_disabled()) |
2633 | return -ENODEV; | |
2634 | ||
1da177e4 | 2635 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2636 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2637 | driver_data->target) || |
2638 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2639 | driver_data->target)) || |
a9a22b57 | 2640 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2641 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2642 | return -EINVAL; |
2643 | ||
2d06d8c4 | 2644 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2645 | |
fdd320da | 2646 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2647 | cpus_read_lock(); |
fdd320da | 2648 | |
0d1857a1 | 2649 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2650 | if (cpufreq_driver) { |
0d1857a1 | 2651 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2652 | ret = -EEXIST; |
2653 | goto out; | |
1da177e4 | 2654 | } |
1c3d85dd | 2655 | cpufreq_driver = driver_data; |
0d1857a1 | 2656 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2657 | |
bc68b7df VK |
2658 | if (driver_data->setpolicy) |
2659 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2660 | ||
7a6c79f2 RW |
2661 | if (cpufreq_boost_supported()) { |
2662 | ret = create_boost_sysfs_file(); | |
2663 | if (ret) | |
2664 | goto err_null_driver; | |
2665 | } | |
6f19efc0 | 2666 | |
8a25a2fd | 2667 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2668 | if (ret) |
6f19efc0 | 2669 | goto err_boost_unreg; |
1da177e4 | 2670 | |
ce1bcfe9 VK |
2671 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2672 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2673 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2674 | ret = -ENODEV; |
ce1bcfe9 VK |
2675 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2676 | driver_data->name); | |
2677 | goto err_if_unreg; | |
1da177e4 LT |
2678 | } |
2679 | ||
a92551e4 SAS |
2680 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2681 | "cpufreq:online", | |
2682 | cpuhp_cpufreq_online, | |
2683 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2684 | if (ret < 0) |
2685 | goto err_if_unreg; | |
2686 | hp_online = ret; | |
5372e054 | 2687 | ret = 0; |
27622b06 | 2688 | |
2d06d8c4 | 2689 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2690 | goto out; |
fdd320da | 2691 | |
8a25a2fd KS |
2692 | err_if_unreg: |
2693 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2694 | err_boost_unreg: |
44139ed4 | 2695 | remove_boost_sysfs_file(); |
8f5bc2ab | 2696 | err_null_driver: |
0d1857a1 | 2697 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2698 | cpufreq_driver = NULL; |
0d1857a1 | 2699 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2700 | out: |
a92551e4 | 2701 | cpus_read_unlock(); |
3834abb4 | 2702 | return ret; |
1da177e4 LT |
2703 | } |
2704 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2705 | ||
1da177e4 LT |
2706 | /** |
2707 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2708 | * | |
bb176f7d | 2709 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2710 | * the right to do so, i.e. if you have succeeded in initialising before! |
2711 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2712 | * currently not initialised. | |
2713 | */ | |
221dee28 | 2714 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2715 | { |
2716 | unsigned long flags; | |
2717 | ||
1c3d85dd | 2718 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2719 | return -EINVAL; |
1da177e4 | 2720 | |
2d06d8c4 | 2721 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2722 | |
454d3a25 | 2723 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2724 | cpus_read_lock(); |
8a25a2fd | 2725 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2726 | remove_boost_sysfs_file(); |
a92551e4 | 2727 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2728 | |
0d1857a1 | 2729 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2730 | |
1c3d85dd | 2731 | cpufreq_driver = NULL; |
6eed9404 | 2732 | |
0d1857a1 | 2733 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2734 | cpus_read_unlock(); |
1da177e4 LT |
2735 | |
2736 | return 0; | |
2737 | } | |
2738 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2739 | |
c82bd444 VK |
2740 | struct kobject *cpufreq_global_kobject; |
2741 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2742 | ||
5a01f2e8 VP |
2743 | static int __init cpufreq_core_init(void) |
2744 | { | |
a7b422cd KRW |
2745 | if (cpufreq_disabled()) |
2746 | return -ENODEV; | |
2747 | ||
8eec1020 | 2748 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2749 | BUG_ON(!cpufreq_global_kobject); |
2750 | ||
5a01f2e8 VP |
2751 | return 0; |
2752 | } | |
d82f2692 | 2753 | module_param(off, int, 0444); |
5a01f2e8 | 2754 | core_initcall(cpufreq_core_init); |