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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 | ||
f7b27061 VK |
45 | /* Iterate over governors */ |
46 | static LIST_HEAD(cpufreq_governor_list); | |
47 | #define for_each_governor(__governor) \ | |
48 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
49 | ||
8412b456 QP |
50 | static char default_governor[CPUFREQ_NAME_LEN]; |
51 | ||
a9909c21 | 52 | /* |
cd878479 | 53 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
54 | * level driver of CPUFreq support, and its spinlock. This lock |
55 | * also protects the cpufreq_cpu_data array. | |
56 | */ | |
1c3d85dd | 57 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 58 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 59 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 60 | |
874f6353 IV |
61 | static DEFINE_STATIC_KEY_FALSE(cpufreq_freq_invariance); |
62 | bool cpufreq_supports_freq_invariance(void) | |
63 | { | |
64 | return static_branch_likely(&cpufreq_freq_invariance); | |
65 | } | |
66 | ||
2f0aea93 VK |
67 | /* Flag to suspend/resume CPUFreq governors */ |
68 | static bool cpufreq_suspended; | |
1da177e4 | 69 | |
9c0ebcf7 VK |
70 | static inline bool has_target(void) |
71 | { | |
72 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
73 | } | |
74 | ||
1da177e4 | 75 | /* internal prototypes */ |
d92d50a4 | 76 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
77 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
78 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
a92604b4 | 79 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); |
1e4f63ae RW |
80 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
81 | struct cpufreq_governor *new_gov, | |
82 | unsigned int new_pol); | |
45482c70 | 83 | |
a9909c21 | 84 | /* |
32ee8c3e DJ |
85 | * Two notifier lists: the "policy" list is involved in the |
86 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
87 | * "transition" list for kernel code that needs to handle |
88 | * changes to devices when the CPU clock speed changes. | |
89 | * The mutex locks both lists. | |
90 | */ | |
e041c683 | 91 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 92 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 93 | |
a7b422cd | 94 | static int off __read_mostly; |
da584455 | 95 | static int cpufreq_disabled(void) |
a7b422cd KRW |
96 | { |
97 | return off; | |
98 | } | |
99 | void disable_cpufreq(void) | |
100 | { | |
101 | off = 1; | |
102 | } | |
29464f28 | 103 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 104 | |
4d5dcc42 VK |
105 | bool have_governor_per_policy(void) |
106 | { | |
0b981e70 | 107 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 108 | } |
3f869d6d | 109 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 110 | |
183edb20 YL |
111 | static struct kobject *cpufreq_global_kobject; |
112 | ||
944e9a03 VK |
113 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
114 | { | |
115 | if (have_governor_per_policy()) | |
116 | return &policy->kobj; | |
117 | else | |
118 | return cpufreq_global_kobject; | |
119 | } | |
120 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
121 | ||
72a4ce34 VK |
122 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
123 | { | |
5720821b | 124 | struct kernel_cpustat kcpustat; |
72a4ce34 | 125 | u64 cur_wall_time; |
5720821b | 126 | u64 idle_time; |
72a4ce34 VK |
127 | u64 busy_time; |
128 | ||
7fb1327e | 129 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 | 130 | |
5720821b FW |
131 | kcpustat_cpu_fetch(&kcpustat, cpu); |
132 | ||
133 | busy_time = kcpustat.cpustat[CPUTIME_USER]; | |
134 | busy_time += kcpustat.cpustat[CPUTIME_SYSTEM]; | |
135 | busy_time += kcpustat.cpustat[CPUTIME_IRQ]; | |
136 | busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ]; | |
137 | busy_time += kcpustat.cpustat[CPUTIME_STEAL]; | |
138 | busy_time += kcpustat.cpustat[CPUTIME_NICE]; | |
72a4ce34 VK |
139 | |
140 | idle_time = cur_wall_time - busy_time; | |
141 | if (wall) | |
7fb1327e | 142 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 143 | |
7fb1327e | 144 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
145 | } |
146 | ||
147 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
148 | { | |
149 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
150 | ||
151 | if (idle_time == -1ULL) | |
152 | return get_cpu_idle_time_jiffy(cpu, wall); | |
153 | else if (!io_busy) | |
154 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
155 | ||
156 | return idle_time; | |
157 | } | |
158 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
159 | ||
70e9e778 VK |
160 | /* |
161 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
162 | * drivers of SMP systems. It will do following: | |
163 | * - validate & show freq table passed | |
164 | * - set policies transition latency | |
165 | * - policy->cpus with all possible CPUs | |
166 | */ | |
c4dcc8a1 | 167 | void cpufreq_generic_init(struct cpufreq_policy *policy, |
70e9e778 VK |
168 | struct cpufreq_frequency_table *table, |
169 | unsigned int transition_latency) | |
170 | { | |
92c99d15 | 171 | policy->freq_table = table; |
70e9e778 VK |
172 | policy->cpuinfo.transition_latency = transition_latency; |
173 | ||
174 | /* | |
58405af6 | 175 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
176 | * share the clock and voltage and clock. |
177 | */ | |
178 | cpumask_setall(policy->cpus); | |
70e9e778 VK |
179 | } |
180 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
181 | ||
1f0bd44e | 182 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
183 | { |
184 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
185 | ||
988bed09 VK |
186 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
187 | } | |
1f0bd44e | 188 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
189 | |
190 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
191 | { | |
192 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
193 | ||
652ed95d | 194 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
195 | pr_err("%s: No %s associated to cpu: %d\n", |
196 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
197 | return 0; |
198 | } | |
199 | ||
200 | return clk_get_rate(policy->clk) / 1000; | |
201 | } | |
202 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
203 | ||
50e9c852 | 204 | /** |
5d094fea RW |
205 | * cpufreq_cpu_get - Return policy for a CPU and mark it as busy. |
206 | * @cpu: CPU to find the policy for. | |
50e9c852 | 207 | * |
5d094fea RW |
208 | * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment |
209 | * the kobject reference counter of that policy. Return a valid policy on | |
210 | * success or NULL on failure. | |
50e9c852 | 211 | * |
5d094fea RW |
212 | * The policy returned by this function has to be released with the help of |
213 | * cpufreq_cpu_put() to balance its kobject reference counter properly. | |
50e9c852 | 214 | */ |
6eed9404 | 215 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 216 | { |
6eed9404 | 217 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
218 | unsigned long flags; |
219 | ||
1b947c90 | 220 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
221 | return NULL; |
222 | ||
1da177e4 | 223 | /* get the cpufreq driver */ |
1c3d85dd | 224 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 225 | |
6eed9404 VK |
226 | if (cpufreq_driver) { |
227 | /* get the CPU */ | |
988bed09 | 228 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
229 | if (policy) |
230 | kobject_get(&policy->kobj); | |
231 | } | |
1da177e4 | 232 | |
6eed9404 | 233 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 234 | |
3a3e9e06 | 235 | return policy; |
a9144436 | 236 | } |
1da177e4 LT |
237 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
238 | ||
50e9c852 | 239 | /** |
5d094fea RW |
240 | * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy. |
241 | * @policy: cpufreq policy returned by cpufreq_cpu_get(). | |
50e9c852 | 242 | */ |
3a3e9e06 | 243 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 244 | { |
6eed9404 | 245 | kobject_put(&policy->kobj); |
1da177e4 LT |
246 | } |
247 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
248 | ||
540a3758 RW |
249 | /** |
250 | * cpufreq_cpu_release - Unlock a policy and decrement its usage counter. | |
251 | * @policy: cpufreq policy returned by cpufreq_cpu_acquire(). | |
252 | */ | |
9083e498 | 253 | void cpufreq_cpu_release(struct cpufreq_policy *policy) |
540a3758 RW |
254 | { |
255 | if (WARN_ON(!policy)) | |
256 | return; | |
257 | ||
258 | lockdep_assert_held(&policy->rwsem); | |
259 | ||
260 | up_write(&policy->rwsem); | |
261 | ||
262 | cpufreq_cpu_put(policy); | |
263 | } | |
264 | ||
265 | /** | |
266 | * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it. | |
267 | * @cpu: CPU to find the policy for. | |
268 | * | |
269 | * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and | |
270 | * if the policy returned by it is not NULL, acquire its rwsem for writing. | |
271 | * Return the policy if it is active or release it and return NULL otherwise. | |
272 | * | |
273 | * The policy returned by this function has to be released with the help of | |
274 | * cpufreq_cpu_release() in order to release its rwsem and balance its usage | |
275 | * counter properly. | |
276 | */ | |
9083e498 | 277 | struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) |
540a3758 RW |
278 | { |
279 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
280 | ||
281 | if (!policy) | |
282 | return NULL; | |
283 | ||
284 | down_write(&policy->rwsem); | |
285 | ||
286 | if (policy_is_inactive(policy)) { | |
287 | cpufreq_cpu_release(policy); | |
288 | return NULL; | |
289 | } | |
290 | ||
291 | return policy; | |
292 | } | |
293 | ||
1da177e4 LT |
294 | /********************************************************************* |
295 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
296 | *********************************************************************/ | |
297 | ||
ec06e586 RW |
298 | /** |
299 | * adjust_jiffies - Adjust the system "loops_per_jiffy". | |
300 | * @val: CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
301 | * @ci: Frequency change information. | |
1da177e4 LT |
302 | * |
303 | * This function alters the system "loops_per_jiffy" for the clock | |
304 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 305 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
306 | * per-CPU loops_per_jiffy value wherever possible. |
307 | */ | |
858119e1 | 308 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 309 | { |
39c132ee VK |
310 | #ifndef CONFIG_SMP |
311 | static unsigned long l_p_j_ref; | |
312 | static unsigned int l_p_j_ref_freq; | |
313 | ||
1da177e4 LT |
314 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
315 | return; | |
316 | ||
317 | if (!l_p_j_ref_freq) { | |
318 | l_p_j_ref = loops_per_jiffy; | |
319 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
320 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
321 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 322 | } |
0b443ead | 323 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
324 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
325 | ci->new); | |
e837f9b5 JP |
326 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
327 | loops_per_jiffy, ci->new); | |
1da177e4 | 328 | } |
1da177e4 | 329 | #endif |
39c132ee | 330 | } |
1da177e4 | 331 | |
20b5324d | 332 | /** |
ec06e586 | 333 | * cpufreq_notify_transition - Notify frequency transition and adjust jiffies. |
20b5324d VK |
334 | * @policy: cpufreq policy to enable fast frequency switching for. |
335 | * @freqs: contain details of the frequency update. | |
336 | * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
337 | * | |
ec06e586 RW |
338 | * This function calls the transition notifiers and adjust_jiffies(). |
339 | * | |
340 | * It is called twice on all CPU frequency changes that have external effects. | |
20b5324d VK |
341 | */ |
342 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
343 | struct cpufreq_freqs *freqs, | |
344 | unsigned int state) | |
1da177e4 | 345 | { |
df24014a VK |
346 | int cpu; |
347 | ||
1da177e4 LT |
348 | BUG_ON(irqs_disabled()); |
349 | ||
d5aaffa9 DB |
350 | if (cpufreq_disabled()) |
351 | return; | |
352 | ||
df24014a | 353 | freqs->policy = policy; |
1c3d85dd | 354 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 355 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 356 | state, freqs->new); |
1da177e4 | 357 | |
1da177e4 LT |
358 | switch (state) { |
359 | case CPUFREQ_PRECHANGE: | |
20b5324d VK |
360 | /* |
361 | * Detect if the driver reported a value as "old frequency" | |
e4472cb3 DJ |
362 | * which is not equal to what the cpufreq core thinks is |
363 | * "old frequency". | |
1da177e4 | 364 | */ |
98015228 VK |
365 | if (policy->cur && policy->cur != freqs->old) { |
366 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", | |
367 | freqs->old, policy->cur); | |
368 | freqs->old = policy->cur; | |
1da177e4 | 369 | } |
20b5324d | 370 | |
df24014a VK |
371 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
372 | CPUFREQ_PRECHANGE, freqs); | |
20b5324d | 373 | |
1da177e4 LT |
374 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
375 | break; | |
e4472cb3 | 376 | |
1da177e4 LT |
377 | case CPUFREQ_POSTCHANGE: |
378 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
20b5324d VK |
379 | pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, |
380 | cpumask_pr_args(policy->cpus)); | |
381 | ||
df24014a VK |
382 | for_each_cpu(cpu, policy->cpus) |
383 | trace_cpu_frequency(freqs->new, cpu); | |
384 | ||
385 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, | |
386 | CPUFREQ_POSTCHANGE, freqs); | |
20b5324d | 387 | |
1aefc75b | 388 | cpufreq_stats_record_transition(policy, freqs->new); |
20b5324d | 389 | policy->cur = freqs->new; |
1da177e4 | 390 | } |
1da177e4 | 391 | } |
bb176f7d | 392 | |
f7ba3b41 | 393 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 394 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
395 | struct cpufreq_freqs *freqs, int transition_failed) |
396 | { | |
397 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
398 | if (!transition_failed) | |
399 | return; | |
400 | ||
401 | swap(freqs->old, freqs->new); | |
402 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
403 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
404 | } | |
f7ba3b41 | 405 | |
12478cf0 SB |
406 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
407 | struct cpufreq_freqs *freqs) | |
408 | { | |
ca654dc3 SB |
409 | |
410 | /* | |
411 | * Catch double invocations of _begin() which lead to self-deadlock. | |
412 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
413 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
414 | * double invocations are very low. Moreover, there are scenarios | |
415 | * where these checks can emit false-positive warnings in these | |
416 | * drivers; so we avoid that by skipping them altogether. | |
417 | */ | |
418 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
419 | && current == policy->transition_task); | |
420 | ||
12478cf0 SB |
421 | wait: |
422 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
423 | ||
424 | spin_lock(&policy->transition_lock); | |
425 | ||
426 | if (unlikely(policy->transition_ongoing)) { | |
427 | spin_unlock(&policy->transition_lock); | |
428 | goto wait; | |
429 | } | |
430 | ||
431 | policy->transition_ongoing = true; | |
ca654dc3 | 432 | policy->transition_task = current; |
12478cf0 SB |
433 | |
434 | spin_unlock(&policy->transition_lock); | |
435 | ||
436 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
437 | } | |
438 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
439 | ||
440 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
441 | struct cpufreq_freqs *freqs, int transition_failed) | |
442 | { | |
0e7ea2f3 | 443 | if (WARN_ON(!policy->transition_ongoing)) |
12478cf0 SB |
444 | return; |
445 | ||
446 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
447 | ||
1a0419b0 IV |
448 | arch_set_freq_scale(policy->related_cpus, |
449 | policy->cur, | |
450 | policy->cpuinfo.max_freq); | |
451 | ||
12478cf0 | 452 | policy->transition_ongoing = false; |
ca654dc3 | 453 | policy->transition_task = NULL; |
12478cf0 SB |
454 | |
455 | wake_up(&policy->transition_wait); | |
456 | } | |
457 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
458 | ||
b7898fda RW |
459 | /* |
460 | * Fast frequency switching status count. Positive means "enabled", negative | |
461 | * means "disabled" and 0 means "not decided yet". | |
462 | */ | |
463 | static int cpufreq_fast_switch_count; | |
464 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
465 | ||
466 | static void cpufreq_list_transition_notifiers(void) | |
467 | { | |
468 | struct notifier_block *nb; | |
469 | ||
470 | pr_info("Registered transition notifiers:\n"); | |
471 | ||
472 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
473 | ||
474 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
d75f773c | 475 | pr_info("%pS\n", nb->notifier_call); |
b7898fda RW |
476 | |
477 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
478 | } | |
479 | ||
480 | /** | |
481 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
482 | * @policy: cpufreq policy to enable fast frequency switching for. | |
483 | * | |
484 | * Try to enable fast frequency switching for @policy. | |
485 | * | |
486 | * The attempt will fail if there is at least one transition notifier registered | |
487 | * at this point, as fast frequency switching is quite fundamentally at odds | |
488 | * with transition notifiers. Thus if successful, it will make registration of | |
489 | * transition notifiers fail going forward. | |
490 | */ | |
491 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
492 | { | |
493 | lockdep_assert_held(&policy->rwsem); | |
494 | ||
495 | if (!policy->fast_switch_possible) | |
496 | return; | |
497 | ||
498 | mutex_lock(&cpufreq_fast_switch_lock); | |
499 | if (cpufreq_fast_switch_count >= 0) { | |
500 | cpufreq_fast_switch_count++; | |
501 | policy->fast_switch_enabled = true; | |
502 | } else { | |
503 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
504 | policy->cpu); | |
505 | cpufreq_list_transition_notifiers(); | |
506 | } | |
507 | mutex_unlock(&cpufreq_fast_switch_lock); | |
508 | } | |
509 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
510 | ||
6c9d9c81 RW |
511 | /** |
512 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
513 | * @policy: cpufreq policy to disable fast frequency switching for. | |
514 | */ | |
515 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
516 | { |
517 | mutex_lock(&cpufreq_fast_switch_lock); | |
518 | if (policy->fast_switch_enabled) { | |
519 | policy->fast_switch_enabled = false; | |
520 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
521 | cpufreq_fast_switch_count--; | |
522 | } | |
523 | mutex_unlock(&cpufreq_fast_switch_lock); | |
524 | } | |
6c9d9c81 | 525 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 526 | |
f9ccdec2 VK |
527 | static unsigned int __resolve_freq(struct cpufreq_policy *policy, |
528 | unsigned int target_freq, unsigned int relation) | |
e3c06236 | 529 | { |
b3beca76 | 530 | unsigned int idx; |
abe8bd02 | 531 | |
b3beca76 | 532 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
abe8bd02 | 533 | |
b3beca76 VK |
534 | if (!cpufreq_driver->target_index) |
535 | return target_freq; | |
abe8bd02 | 536 | |
b3beca76 VK |
537 | idx = cpufreq_frequency_table_target(policy, target_freq, relation); |
538 | policy->cached_resolved_idx = idx; | |
539 | policy->cached_target_freq = target_freq; | |
540 | return policy->freq_table[idx].frequency; | |
e3c06236 | 541 | } |
f9ccdec2 VK |
542 | |
543 | /** | |
544 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
545 | * one. | |
546 | * @policy: associated policy to interrogate | |
547 | * @target_freq: target frequency to resolve. | |
548 | * | |
549 | * The target to driver frequency mapping is cached in the policy. | |
550 | * | |
551 | * Return: Lowest driver-supported frequency greater than or equal to the | |
552 | * given target_freq, subject to policy (min/max) and driver limitations. | |
553 | */ | |
554 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
555 | unsigned int target_freq) | |
556 | { | |
557 | return __resolve_freq(policy, target_freq, CPUFREQ_RELATION_L); | |
558 | } | |
ae2c1ca6 | 559 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 560 | |
aa7519af VK |
561 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
562 | { | |
563 | unsigned int latency; | |
564 | ||
565 | if (policy->transition_delay_us) | |
566 | return policy->transition_delay_us; | |
567 | ||
568 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
569 | if (latency) { |
570 | /* | |
571 | * For platforms that can change the frequency very fast (< 10 | |
572 | * us), the above formula gives a decent transition delay. But | |
573 | * for platforms where transition_latency is in milliseconds, it | |
574 | * ends up giving unrealistic values. | |
575 | * | |
576 | * Cap the default transition delay to 10 ms, which seems to be | |
577 | * a reasonable amount of time after which we should reevaluate | |
578 | * the frequency. | |
579 | */ | |
580 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
581 | } | |
aa7519af VK |
582 | |
583 | return LATENCY_MULTIPLIER; | |
584 | } | |
585 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
586 | ||
1da177e4 LT |
587 | /********************************************************************* |
588 | * SYSFS INTERFACE * | |
589 | *********************************************************************/ | |
8a5c74a1 | 590 | static ssize_t show_boost(struct kobject *kobj, |
625c85a6 | 591 | struct kobj_attribute *attr, char *buf) |
6f19efc0 LM |
592 | { |
593 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
594 | } | |
595 | ||
625c85a6 VK |
596 | static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, |
597 | const char *buf, size_t count) | |
6f19efc0 LM |
598 | { |
599 | int ret, enable; | |
600 | ||
601 | ret = sscanf(buf, "%d", &enable); | |
602 | if (ret != 1 || enable < 0 || enable > 1) | |
603 | return -EINVAL; | |
604 | ||
605 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
606 | pr_err("%s: Cannot %s BOOST!\n", |
607 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
608 | return -EINVAL; |
609 | } | |
610 | ||
e837f9b5 JP |
611 | pr_debug("%s: cpufreq BOOST %s\n", |
612 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
613 | |
614 | return count; | |
615 | } | |
616 | define_one_global_rw(boost); | |
1da177e4 | 617 | |
42f91fa1 | 618 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
619 | { |
620 | struct cpufreq_governor *t; | |
621 | ||
f7b27061 | 622 | for_each_governor(t) |
7c4f4539 | 623 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
624 | return t; |
625 | ||
626 | return NULL; | |
627 | } | |
628 | ||
8cc46ae5 VK |
629 | static struct cpufreq_governor *get_governor(const char *str_governor) |
630 | { | |
631 | struct cpufreq_governor *t; | |
632 | ||
633 | mutex_lock(&cpufreq_governor_mutex); | |
634 | t = find_governor(str_governor); | |
635 | if (!t) | |
636 | goto unlock; | |
637 | ||
638 | if (!try_module_get(t->owner)) | |
639 | t = NULL; | |
640 | ||
641 | unlock: | |
642 | mutex_unlock(&cpufreq_governor_mutex); | |
643 | ||
644 | return t; | |
645 | } | |
646 | ||
1e4f63ae | 647 | static unsigned int cpufreq_parse_policy(char *str_governor) |
ab05d97a | 648 | { |
1e4f63ae RW |
649 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) |
650 | return CPUFREQ_POLICY_PERFORMANCE; | |
651 | ||
652 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) | |
653 | return CPUFREQ_POLICY_POWERSAVE; | |
654 | ||
655 | return CPUFREQ_POLICY_UNKNOWN; | |
ab05d97a YH |
656 | } |
657 | ||
1da177e4 | 658 | /** |
5ddc6d4e | 659 | * cpufreq_parse_governor - parse a governor string only for has_target() |
1e4f63ae | 660 | * @str_governor: Governor name. |
1da177e4 | 661 | */ |
1e4f63ae | 662 | static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor) |
1da177e4 | 663 | { |
ab05d97a | 664 | struct cpufreq_governor *t; |
045149e6 | 665 | |
8cc46ae5 VK |
666 | t = get_governor(str_governor); |
667 | if (t) | |
668 | return t; | |
ea714970 | 669 | |
8cc46ae5 VK |
670 | if (request_module("cpufreq_%s", str_governor)) |
671 | return NULL; | |
045149e6 | 672 | |
8cc46ae5 | 673 | return get_governor(str_governor); |
1da177e4 | 674 | } |
1da177e4 | 675 | |
a9909c21 | 676 | /* |
e08f5f5b GS |
677 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
678 | * print out cpufreq information | |
1da177e4 LT |
679 | * |
680 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
681 | * "unsigned int". | |
682 | */ | |
683 | ||
32ee8c3e DJ |
684 | #define show_one(file_name, object) \ |
685 | static ssize_t show_##file_name \ | |
905d77cd | 686 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 687 | { \ |
29464f28 | 688 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
689 | } |
690 | ||
691 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
692 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 693 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
694 | show_one(scaling_min_freq, min); |
695 | show_one(scaling_max_freq, max); | |
c034b02e | 696 | |
f8475cef LB |
697 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
698 | { | |
699 | return 0; | |
700 | } | |
701 | ||
09347b29 | 702 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
703 | { |
704 | ssize_t ret; | |
f8475cef | 705 | unsigned int freq; |
c034b02e | 706 | |
f8475cef LB |
707 | freq = arch_freq_get_on_cpu(policy->cpu); |
708 | if (freq) | |
709 | ret = sprintf(buf, "%u\n", freq); | |
681fe684 | 710 | else if (cpufreq_driver->setpolicy && cpufreq_driver->get) |
c034b02e DB |
711 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
712 | else | |
713 | ret = sprintf(buf, "%u\n", policy->cur); | |
714 | return ret; | |
715 | } | |
1da177e4 | 716 | |
a9909c21 | 717 | /* |
1da177e4 LT |
718 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access |
719 | */ | |
720 | #define store_one(file_name, object) \ | |
721 | static ssize_t store_##file_name \ | |
905d77cd | 722 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 723 | { \ |
18c49926 VK |
724 | unsigned long val; \ |
725 | int ret; \ | |
1da177e4 | 726 | \ |
18c49926 | 727 | ret = sscanf(buf, "%lu", &val); \ |
1da177e4 LT |
728 | if (ret != 1) \ |
729 | return -EINVAL; \ | |
730 | \ | |
3000ce3c | 731 | ret = freq_qos_update_request(policy->object##_freq_req, val);\ |
18c49926 | 732 | return ret >= 0 ? count : ret; \ |
1da177e4 LT |
733 | } |
734 | ||
29464f28 DJ |
735 | store_one(scaling_min_freq, min); |
736 | store_one(scaling_max_freq, max); | |
1da177e4 | 737 | |
a9909c21 | 738 | /* |
1da177e4 LT |
739 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware |
740 | */ | |
905d77cd DJ |
741 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
742 | char *buf) | |
1da177e4 | 743 | { |
d92d50a4 | 744 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
745 | |
746 | if (cur_freq) | |
747 | return sprintf(buf, "%u\n", cur_freq); | |
748 | ||
749 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
750 | } |
751 | ||
a9909c21 | 752 | /* |
1da177e4 LT |
753 | * show_scaling_governor - show the current policy for the specified CPU |
754 | */ | |
905d77cd | 755 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 756 | { |
29464f28 | 757 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
758 | return sprintf(buf, "powersave\n"); |
759 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
760 | return sprintf(buf, "performance\n"); | |
761 | else if (policy->governor) | |
4b972f0b | 762 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 763 | policy->governor->name); |
1da177e4 LT |
764 | return -EINVAL; |
765 | } | |
766 | ||
a9909c21 | 767 | /* |
1da177e4 LT |
768 | * store_scaling_governor - store policy for the specified CPU |
769 | */ | |
905d77cd DJ |
770 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
771 | const char *buf, size_t count) | |
1da177e4 | 772 | { |
1e4f63ae | 773 | char str_governor[16]; |
5136fa56 | 774 | int ret; |
1da177e4 | 775 | |
29464f28 | 776 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
777 | if (ret != 1) |
778 | return -EINVAL; | |
779 | ||
ab05d97a | 780 | if (cpufreq_driver->setpolicy) { |
1e4f63ae RW |
781 | unsigned int new_pol; |
782 | ||
783 | new_pol = cpufreq_parse_policy(str_governor); | |
784 | if (!new_pol) | |
ab05d97a | 785 | return -EINVAL; |
1e4f63ae RW |
786 | |
787 | ret = cpufreq_set_policy(policy, NULL, new_pol); | |
ab05d97a | 788 | } else { |
1e4f63ae RW |
789 | struct cpufreq_governor *new_gov; |
790 | ||
791 | new_gov = cpufreq_parse_governor(str_governor); | |
792 | if (!new_gov) | |
ab05d97a | 793 | return -EINVAL; |
1da177e4 | 794 | |
1e4f63ae RW |
795 | ret = cpufreq_set_policy(policy, new_gov, |
796 | CPUFREQ_POLICY_UNKNOWN); | |
a8b149d3 | 797 | |
1e4f63ae RW |
798 | module_put(new_gov->owner); |
799 | } | |
a8b149d3 | 800 | |
88dc4384 | 801 | return ret ? ret : count; |
1da177e4 LT |
802 | } |
803 | ||
a9909c21 | 804 | /* |
1da177e4 LT |
805 | * show_scaling_driver - show the cpufreq driver currently loaded |
806 | */ | |
905d77cd | 807 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 808 | { |
1c3d85dd | 809 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
810 | } |
811 | ||
a9909c21 | 812 | /* |
1da177e4 LT |
813 | * show_scaling_available_governors - show the available CPUfreq governors |
814 | */ | |
905d77cd DJ |
815 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
816 | char *buf) | |
1da177e4 LT |
817 | { |
818 | ssize_t i = 0; | |
819 | struct cpufreq_governor *t; | |
820 | ||
9c0ebcf7 | 821 | if (!has_target()) { |
1da177e4 LT |
822 | i += sprintf(buf, "performance powersave"); |
823 | goto out; | |
824 | } | |
825 | ||
8cc46ae5 | 826 | mutex_lock(&cpufreq_governor_mutex); |
f7b27061 | 827 | for_each_governor(t) { |
29464f28 DJ |
828 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
829 | - (CPUFREQ_NAME_LEN + 2))) | |
8cc46ae5 | 830 | break; |
4b972f0b | 831 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 832 | } |
8cc46ae5 | 833 | mutex_unlock(&cpufreq_governor_mutex); |
7d5e350f | 834 | out: |
1da177e4 LT |
835 | i += sprintf(&buf[i], "\n"); |
836 | return i; | |
837 | } | |
e8628dd0 | 838 | |
f4fd3797 | 839 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
840 | { |
841 | ssize_t i = 0; | |
842 | unsigned int cpu; | |
843 | ||
835481d9 | 844 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
845 | if (i) |
846 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
847 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
848 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 849 | break; |
1da177e4 LT |
850 | } |
851 | i += sprintf(&buf[i], "\n"); | |
852 | return i; | |
853 | } | |
f4fd3797 | 854 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 855 | |
a9909c21 | 856 | /* |
e8628dd0 DW |
857 | * show_related_cpus - show the CPUs affected by each transition even if |
858 | * hw coordination is in use | |
859 | */ | |
860 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
861 | { | |
f4fd3797 | 862 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
863 | } |
864 | ||
a9909c21 | 865 | /* |
e8628dd0 DW |
866 | * show_affected_cpus - show the CPUs affected by each transition |
867 | */ | |
868 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
869 | { | |
f4fd3797 | 870 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
871 | } |
872 | ||
9e76988e | 873 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 874 | const char *buf, size_t count) |
9e76988e VP |
875 | { |
876 | unsigned int freq = 0; | |
877 | unsigned int ret; | |
878 | ||
879000f9 | 879 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
880 | return -EINVAL; |
881 | ||
882 | ret = sscanf(buf, "%u", &freq); | |
883 | if (ret != 1) | |
884 | return -EINVAL; | |
885 | ||
886 | policy->governor->store_setspeed(policy, freq); | |
887 | ||
888 | return count; | |
889 | } | |
890 | ||
891 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
892 | { | |
879000f9 | 893 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
894 | return sprintf(buf, "<unsupported>\n"); |
895 | ||
896 | return policy->governor->show_setspeed(policy, buf); | |
897 | } | |
1da177e4 | 898 | |
a9909c21 | 899 | /* |
8bf1ac72 | 900 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
901 | */ |
902 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
903 | { | |
904 | unsigned int limit; | |
905 | int ret; | |
b23aa311 YH |
906 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
907 | if (!ret) | |
908 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
909 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
910 | } | |
911 | ||
6dad2a29 BP |
912 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
913 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
914 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
915 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
916 | cpufreq_freq_attr_ro(scaling_available_governors); | |
917 | cpufreq_freq_attr_ro(scaling_driver); | |
918 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
919 | cpufreq_freq_attr_ro(bios_limit); | |
920 | cpufreq_freq_attr_ro(related_cpus); | |
921 | cpufreq_freq_attr_ro(affected_cpus); | |
922 | cpufreq_freq_attr_rw(scaling_min_freq); | |
923 | cpufreq_freq_attr_rw(scaling_max_freq); | |
924 | cpufreq_freq_attr_rw(scaling_governor); | |
925 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 926 | |
905d77cd | 927 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
928 | &cpuinfo_min_freq.attr, |
929 | &cpuinfo_max_freq.attr, | |
ed129784 | 930 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
931 | &scaling_min_freq.attr, |
932 | &scaling_max_freq.attr, | |
933 | &affected_cpus.attr, | |
e8628dd0 | 934 | &related_cpus.attr, |
1da177e4 LT |
935 | &scaling_governor.attr, |
936 | &scaling_driver.attr, | |
937 | &scaling_available_governors.attr, | |
9e76988e | 938 | &scaling_setspeed.attr, |
1da177e4 LT |
939 | NULL |
940 | }; | |
941 | ||
29464f28 DJ |
942 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
943 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 944 | |
29464f28 | 945 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 946 | { |
905d77cd DJ |
947 | struct cpufreq_policy *policy = to_policy(kobj); |
948 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 949 | ssize_t ret; |
6eed9404 | 950 | |
e6e8df07 KS |
951 | if (!fattr->show) |
952 | return -EIO; | |
953 | ||
ad7722da | 954 | down_read(&policy->rwsem); |
6541aef0 | 955 | ret = fattr->show(policy, buf); |
ad7722da | 956 | up_read(&policy->rwsem); |
1b750e3b | 957 | |
1da177e4 LT |
958 | return ret; |
959 | } | |
960 | ||
905d77cd DJ |
961 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
962 | const char *buf, size_t count) | |
1da177e4 | 963 | { |
905d77cd DJ |
964 | struct cpufreq_policy *policy = to_policy(kobj); |
965 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 966 | ssize_t ret = -EINVAL; |
6eed9404 | 967 | |
e6e8df07 KS |
968 | if (!fattr->store) |
969 | return -EIO; | |
970 | ||
9b3d9bb3 WL |
971 | /* |
972 | * cpus_read_trylock() is used here to work around a circular lock | |
973 | * dependency problem with respect to the cpufreq_register_driver(). | |
974 | */ | |
975 | if (!cpus_read_trylock()) | |
976 | return -EBUSY; | |
4f750c93 | 977 | |
6541aef0 RW |
978 | if (cpu_online(policy->cpu)) { |
979 | down_write(&policy->rwsem); | |
e08f5f5b | 980 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
981 | up_write(&policy->rwsem); |
982 | } | |
e08f5f5b | 983 | |
a92551e4 | 984 | cpus_read_unlock(); |
4f750c93 | 985 | |
1da177e4 LT |
986 | return ret; |
987 | } | |
988 | ||
905d77cd | 989 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 990 | { |
905d77cd | 991 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 992 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
993 | complete(&policy->kobj_unregister); |
994 | } | |
995 | ||
52cf25d0 | 996 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
997 | .show = show, |
998 | .store = store, | |
999 | }; | |
1000 | ||
1001 | static struct kobj_type ktype_cpufreq = { | |
1002 | .sysfs_ops = &sysfs_ops, | |
1003 | .default_attrs = default_attrs, | |
1004 | .release = cpufreq_sysfs_release, | |
1005 | }; | |
1006 | ||
2da3e586 XW |
1007 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu, |
1008 | struct device *dev) | |
87549141 | 1009 | { |
67d874c3 | 1010 | if (unlikely(!dev)) |
2f0ba790 RW |
1011 | return; |
1012 | ||
1013 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
1014 | return; | |
1015 | ||
26619804 | 1016 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
1017 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
1018 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
1019 | } |
1020 | ||
26619804 VK |
1021 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
1022 | struct device *dev) | |
87549141 | 1023 | { |
26619804 VK |
1024 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1025 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
1026 | } |
1027 | ||
d9612a49 | 1028 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
1029 | { |
1030 | struct freq_attr **drv_attr; | |
909a694e | 1031 | int ret = 0; |
909a694e | 1032 | |
909a694e | 1033 | /* set up files for this cpu device */ |
1c3d85dd | 1034 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1035 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1036 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1037 | if (ret) | |
6d4e81ed | 1038 | return ret; |
909a694e DJ |
1039 | drv_attr++; |
1040 | } | |
1c3d85dd | 1041 | if (cpufreq_driver->get) { |
909a694e DJ |
1042 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1043 | if (ret) | |
6d4e81ed | 1044 | return ret; |
909a694e | 1045 | } |
c034b02e DB |
1046 | |
1047 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1048 | if (ret) | |
6d4e81ed | 1049 | return ret; |
c034b02e | 1050 | |
1c3d85dd | 1051 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1052 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1053 | if (ret) | |
6d4e81ed | 1054 | return ret; |
e2f74f35 | 1055 | } |
909a694e | 1056 | |
26619804 | 1057 | return 0; |
e18f1682 SB |
1058 | } |
1059 | ||
7f0fa40f | 1060 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1061 | { |
1e4f63ae RW |
1062 | struct cpufreq_governor *gov = NULL; |
1063 | unsigned int pol = CPUFREQ_POLICY_UNKNOWN; | |
8cc46ae5 | 1064 | int ret; |
ab05d97a YH |
1065 | |
1066 | if (has_target()) { | |
1e4f63ae | 1067 | /* Update policy governor to the one used before hotplug. */ |
8cc46ae5 | 1068 | gov = get_governor(policy->last_governor); |
ab05d97a YH |
1069 | if (gov) { |
1070 | pr_debug("Restoring governor %s for cpu %d\n", | |
8412b456 | 1071 | gov->name, policy->cpu); |
1e4f63ae | 1072 | } else { |
8412b456 QP |
1073 | gov = get_governor(default_governor); |
1074 | } | |
1075 | ||
1076 | if (!gov) { | |
1077 | gov = cpufreq_default_governor(); | |
8412b456 | 1078 | __module_get(gov->owner); |
ab05d97a | 1079 | } |
8412b456 | 1080 | |
de1df26b | 1081 | } else { |
8412b456 | 1082 | |
ab05d97a YH |
1083 | /* Use the default policy if there is no last_policy. */ |
1084 | if (policy->last_policy) { | |
1e4f63ae | 1085 | pol = policy->last_policy; |
8412b456 QP |
1086 | } else { |
1087 | pol = cpufreq_parse_policy(default_governor); | |
f5739cb0 | 1088 | /* |
8412b456 | 1089 | * In case the default governor is neither "performance" |
f5739cb0 RW |
1090 | * nor "powersave", fall back to the initial policy |
1091 | * value set by the driver. | |
1092 | */ | |
1093 | if (pol == CPUFREQ_POLICY_UNKNOWN) | |
1094 | pol = policy->policy; | |
ab05d97a | 1095 | } |
f5739cb0 RW |
1096 | if (pol != CPUFREQ_POLICY_PERFORMANCE && |
1097 | pol != CPUFREQ_POLICY_POWERSAVE) | |
1098 | return -ENODATA; | |
69030dd1 | 1099 | } |
ab05d97a | 1100 | |
8cc46ae5 VK |
1101 | ret = cpufreq_set_policy(policy, gov, pol); |
1102 | if (gov) | |
1103 | module_put(gov->owner); | |
1104 | ||
1105 | return ret; | |
909a694e DJ |
1106 | } |
1107 | ||
d9612a49 | 1108 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1109 | { |
9c0ebcf7 | 1110 | int ret = 0; |
fcf80582 | 1111 | |
bb29ae15 VK |
1112 | /* Has this CPU been taken care of already? */ |
1113 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1114 | return 0; | |
1115 | ||
49f18560 | 1116 | down_write(&policy->rwsem); |
45482c70 RW |
1117 | if (has_target()) |
1118 | cpufreq_stop_governor(policy); | |
fcf80582 | 1119 | |
fcf80582 | 1120 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1121 | |
9c0ebcf7 | 1122 | if (has_target()) { |
0a300767 | 1123 | ret = cpufreq_start_governor(policy); |
49f18560 | 1124 | if (ret) |
3de9bdeb | 1125 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1126 | } |
49f18560 VK |
1127 | up_write(&policy->rwsem); |
1128 | return ret; | |
fcf80582 | 1129 | } |
1da177e4 | 1130 | |
c57b25bd | 1131 | void refresh_frequency_limits(struct cpufreq_policy *policy) |
70a59fde | 1132 | { |
67d874c3 | 1133 | if (!policy_is_inactive(policy)) { |
67d874c3 | 1134 | pr_debug("updating policy for CPU %u\n", policy->cpu); |
70a59fde | 1135 | |
1e4f63ae | 1136 | cpufreq_set_policy(policy, policy->governor, policy->policy); |
67d874c3 | 1137 | } |
70a59fde | 1138 | } |
c57b25bd | 1139 | EXPORT_SYMBOL(refresh_frequency_limits); |
70a59fde | 1140 | |
11eb69b9 VK |
1141 | static void handle_update(struct work_struct *work) |
1142 | { | |
1143 | struct cpufreq_policy *policy = | |
1144 | container_of(work, struct cpufreq_policy, update); | |
70a59fde VK |
1145 | |
1146 | pr_debug("handle_update for cpu %u called\n", policy->cpu); | |
67d874c3 | 1147 | down_write(&policy->rwsem); |
70a59fde | 1148 | refresh_frequency_limits(policy); |
67d874c3 VK |
1149 | up_write(&policy->rwsem); |
1150 | } | |
1151 | ||
1152 | static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq, | |
1153 | void *data) | |
1154 | { | |
1155 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min); | |
1156 | ||
1157 | schedule_work(&policy->update); | |
1158 | return 0; | |
1159 | } | |
1160 | ||
1161 | static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq, | |
1162 | void *data) | |
1163 | { | |
1164 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max); | |
1165 | ||
1166 | schedule_work(&policy->update); | |
1167 | return 0; | |
1168 | } | |
1169 | ||
1170 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) | |
1171 | { | |
1172 | struct kobject *kobj; | |
1173 | struct completion *cmp; | |
1174 | ||
1175 | down_write(&policy->rwsem); | |
1176 | cpufreq_stats_free_table(policy); | |
1177 | kobj = &policy->kobj; | |
1178 | cmp = &policy->kobj_unregister; | |
1179 | up_write(&policy->rwsem); | |
1180 | kobject_put(kobj); | |
1181 | ||
1182 | /* | |
1183 | * We need to make sure that the underlying kobj is | |
1184 | * actually not referenced anymore by anybody before we | |
1185 | * proceed with unloading. | |
1186 | */ | |
1187 | pr_debug("waiting for dropping of refcount\n"); | |
1188 | wait_for_completion(cmp); | |
1189 | pr_debug("wait complete\n"); | |
fcf80582 | 1190 | } |
1da177e4 | 1191 | |
a34e63b1 | 1192 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1193 | { |
1194 | struct cpufreq_policy *policy; | |
67d874c3 | 1195 | struct device *dev = get_cpu_device(cpu); |
edd4a893 | 1196 | int ret; |
e9698cc5 | 1197 | |
67d874c3 VK |
1198 | if (!dev) |
1199 | return NULL; | |
1200 | ||
e9698cc5 SB |
1201 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1202 | if (!policy) | |
1203 | return NULL; | |
1204 | ||
1205 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1206 | goto err_free_policy; | |
1207 | ||
1208 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1209 | goto err_free_cpumask; | |
1210 | ||
559ed407 RW |
1211 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1212 | goto err_free_rcpumask; | |
1213 | ||
edd4a893 VK |
1214 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1215 | cpufreq_global_kobject, "policy%u", cpu); | |
1216 | if (ret) { | |
67d874c3 | 1217 | dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret); |
2acb9bda RW |
1218 | /* |
1219 | * The entire policy object will be freed below, but the extra | |
1220 | * memory allocated for the kobject name needs to be freed by | |
1221 | * releasing the kobject. | |
1222 | */ | |
4ebe36c9 | 1223 | kobject_put(&policy->kobj); |
edd4a893 VK |
1224 | goto err_free_real_cpus; |
1225 | } | |
1226 | ||
3000ce3c RW |
1227 | freq_constraints_init(&policy->constraints); |
1228 | ||
67d874c3 VK |
1229 | policy->nb_min.notifier_call = cpufreq_notifier_min; |
1230 | policy->nb_max.notifier_call = cpufreq_notifier_max; | |
1231 | ||
3000ce3c RW |
1232 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MIN, |
1233 | &policy->nb_min); | |
67d874c3 VK |
1234 | if (ret) { |
1235 | dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n", | |
1236 | ret, cpumask_pr_args(policy->cpus)); | |
1237 | goto err_kobj_remove; | |
1238 | } | |
1239 | ||
3000ce3c RW |
1240 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MAX, |
1241 | &policy->nb_max); | |
67d874c3 VK |
1242 | if (ret) { |
1243 | dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n", | |
1244 | ret, cpumask_pr_args(policy->cpus)); | |
1245 | goto err_min_qos_notifier; | |
1246 | } | |
1247 | ||
c88a1f8b | 1248 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1249 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1250 | spin_lock_init(&policy->transition_lock); |
1251 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1252 | init_completion(&policy->kobj_unregister); |
1253 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1254 | |
a34e63b1 | 1255 | policy->cpu = cpu; |
e9698cc5 SB |
1256 | return policy; |
1257 | ||
67d874c3 | 1258 | err_min_qos_notifier: |
3000ce3c RW |
1259 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, |
1260 | &policy->nb_min); | |
67d874c3 VK |
1261 | err_kobj_remove: |
1262 | cpufreq_policy_put_kobj(policy); | |
edd4a893 VK |
1263 | err_free_real_cpus: |
1264 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1265 | err_free_rcpumask: |
1266 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1267 | err_free_cpumask: |
1268 | free_cpumask_var(policy->cpus); | |
1269 | err_free_policy: | |
1270 | kfree(policy); | |
1271 | ||
1272 | return NULL; | |
1273 | } | |
1274 | ||
f9f41e3e | 1275 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1276 | { |
988bed09 VK |
1277 | unsigned long flags; |
1278 | int cpu; | |
1279 | ||
1280 | /* Remove policy from list */ | |
1281 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1282 | list_del(&policy->policy_list); | |
1283 | ||
1284 | for_each_cpu(cpu, policy->related_cpus) | |
1285 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1286 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1287 | ||
3000ce3c RW |
1288 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MAX, |
1289 | &policy->nb_max); | |
1290 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, | |
1291 | &policy->nb_min); | |
6a149036 | 1292 | |
6941051d SH |
1293 | /* Cancel any pending policy->update work before freeing the policy. */ |
1294 | cancel_work_sync(&policy->update); | |
6a149036 VK |
1295 | |
1296 | if (policy->max_freq_req) { | |
1297 | /* | |
1298 | * CPUFREQ_CREATE_POLICY notification is sent only after | |
1299 | * successfully adding max_freq_req request. | |
1300 | */ | |
1301 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1302 | CPUFREQ_REMOVE_POLICY, policy); | |
3000ce3c | 1303 | freq_qos_remove_request(policy->max_freq_req); |
6a149036 VK |
1304 | } |
1305 | ||
3000ce3c | 1306 | freq_qos_remove_request(policy->min_freq_req); |
18c49926 | 1307 | kfree(policy->min_freq_req); |
67d874c3 | 1308 | |
f9f41e3e | 1309 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1310 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1311 | free_cpumask_var(policy->related_cpus); |
1312 | free_cpumask_var(policy->cpus); | |
1313 | kfree(policy); | |
1314 | } | |
1315 | ||
0b275352 | 1316 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1317 | { |
7f0c020a | 1318 | struct cpufreq_policy *policy; |
194d99c7 | 1319 | bool new_policy; |
1da177e4 | 1320 | unsigned long flags; |
0b275352 RW |
1321 | unsigned int j; |
1322 | int ret; | |
87549141 | 1323 | |
0b275352 | 1324 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1325 | |
bb29ae15 | 1326 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1327 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1328 | if (policy) { |
9104bb26 | 1329 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1330 | if (!policy_is_inactive(policy)) |
d9612a49 | 1331 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1332 | |
11ce707e | 1333 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1334 | new_policy = false; |
11ce707e RW |
1335 | down_write(&policy->rwsem); |
1336 | policy->cpu = cpu; | |
1337 | policy->governor = NULL; | |
1338 | up_write(&policy->rwsem); | |
1339 | } else { | |
194d99c7 | 1340 | new_policy = true; |
a34e63b1 | 1341 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1342 | if (!policy) |
d4d854d6 | 1343 | return -ENOMEM; |
72368d12 | 1344 | } |
0d66b91e | 1345 | |
91a12e91 VK |
1346 | if (!new_policy && cpufreq_driver->online) { |
1347 | ret = cpufreq_driver->online(policy); | |
1348 | if (ret) { | |
1349 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1350 | __LINE__); | |
1351 | goto out_exit_policy; | |
1352 | } | |
1da177e4 | 1353 | |
91a12e91 VK |
1354 | /* Recover policy->cpus using related_cpus */ |
1355 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1356 | } else { | |
1357 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1358 | |
91a12e91 VK |
1359 | /* |
1360 | * Call driver. From then on the cpufreq must be able | |
1361 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1362 | */ | |
1363 | ret = cpufreq_driver->init(policy); | |
1364 | if (ret) { | |
1365 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1366 | __LINE__); | |
1367 | goto out_free_policy; | |
1368 | } | |
d417e069 | 1369 | |
3b718057 RW |
1370 | /* |
1371 | * The initialization has succeeded and the policy is online. | |
1372 | * If there is a problem with its frequency table, take it | |
1373 | * offline and drop it. | |
1374 | */ | |
91a12e91 VK |
1375 | ret = cpufreq_table_validate_and_sort(policy); |
1376 | if (ret) | |
3b718057 | 1377 | goto out_offline_policy; |
6d4e81ed | 1378 | |
4d1f3a5b | 1379 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1380 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1381 | } |
559ed407 | 1382 | |
91a12e91 | 1383 | down_write(&policy->rwsem); |
5a7e56a5 VK |
1384 | /* |
1385 | * affected cpus must always be the one, which are online. We aren't | |
1386 | * managing offline cpus here. | |
1387 | */ | |
1388 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1389 | ||
194d99c7 | 1390 | if (new_policy) { |
2f0ba790 | 1391 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1392 | per_cpu(cpufreq_cpu_data, j) = policy; |
2da3e586 | 1393 | add_cpu_dev_symlink(policy, j, get_cpu_device(j)); |
2f0ba790 | 1394 | } |
18c49926 VK |
1395 | |
1396 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1397 | GFP_KERNEL); | |
b96f0384 WS |
1398 | if (!policy->min_freq_req) { |
1399 | ret = -ENOMEM; | |
18c49926 | 1400 | goto out_destroy_policy; |
b96f0384 | 1401 | } |
18c49926 | 1402 | |
3000ce3c RW |
1403 | ret = freq_qos_add_request(&policy->constraints, |
1404 | policy->min_freq_req, FREQ_QOS_MIN, | |
d74d6c2b | 1405 | FREQ_QOS_MIN_DEFAULT_VALUE); |
18c49926 VK |
1406 | if (ret < 0) { |
1407 | /* | |
3000ce3c | 1408 | * So we don't call freq_qos_remove_request() for an |
18c49926 VK |
1409 | * uninitialized request. |
1410 | */ | |
1411 | kfree(policy->min_freq_req); | |
1412 | policy->min_freq_req = NULL; | |
18c49926 VK |
1413 | goto out_destroy_policy; |
1414 | } | |
1415 | ||
1416 | /* | |
1417 | * This must be initialized right here to avoid calling | |
3000ce3c | 1418 | * freq_qos_remove_request() on uninitialized request in case |
18c49926 VK |
1419 | * of errors. |
1420 | */ | |
1421 | policy->max_freq_req = policy->min_freq_req + 1; | |
1422 | ||
3000ce3c RW |
1423 | ret = freq_qos_add_request(&policy->constraints, |
1424 | policy->max_freq_req, FREQ_QOS_MAX, | |
d74d6c2b | 1425 | FREQ_QOS_MAX_DEFAULT_VALUE); |
18c49926 VK |
1426 | if (ret < 0) { |
1427 | policy->max_freq_req = NULL; | |
18c49926 VK |
1428 | goto out_destroy_policy; |
1429 | } | |
6a149036 VK |
1430 | |
1431 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1432 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1433 | } |
652ed95d | 1434 | |
5ddc6d4e | 1435 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1436 | policy->cur = cpufreq_driver->get(policy->cpu); |
1437 | if (!policy->cur) { | |
b96f0384 | 1438 | ret = -EIO; |
da60ce9f | 1439 | pr_err("%s: ->get() failed\n", __func__); |
d417e069 | 1440 | goto out_destroy_policy; |
da60ce9f VK |
1441 | } |
1442 | } | |
1443 | ||
d3916691 VK |
1444 | /* |
1445 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1446 | * frequency table present with cpufreq core. In such cases CPU might be | |
1447 | * unstable if it has to run on that frequency for long duration of time | |
1448 | * and so its better to set it to a frequency which is specified in | |
1449 | * freq-table. This also makes cpufreq stats inconsistent as | |
1450 | * cpufreq-stats would fail to register because current frequency of CPU | |
1451 | * isn't found in freq-table. | |
1452 | * | |
1453 | * Because we don't want this change to effect boot process badly, we go | |
1454 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1455 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1456 | * is initialized to zero). | |
1457 | * | |
1458 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1459 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1460 | * equal to target-freq. | |
1461 | */ | |
1462 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1463 | && has_target()) { | |
97148d0a VK |
1464 | unsigned int old_freq = policy->cur; |
1465 | ||
d3916691 | 1466 | /* Are we running at unknown frequency ? */ |
97148d0a | 1467 | ret = cpufreq_frequency_table_get_index(policy, old_freq); |
d3916691 | 1468 | if (ret == -EINVAL) { |
97148d0a VK |
1469 | ret = __cpufreq_driver_target(policy, old_freq - 1, |
1470 | CPUFREQ_RELATION_L); | |
d3916691 VK |
1471 | |
1472 | /* | |
1473 | * Reaching here after boot in a few seconds may not | |
1474 | * mean that system will remain stable at "unknown" | |
1475 | * frequency for longer duration. Hence, a BUG_ON(). | |
1476 | */ | |
1477 | BUG_ON(ret); | |
97148d0a VK |
1478 | pr_info("%s: CPU%d: Running at unlisted initial frequency: %u KHz, changing to: %u KHz\n", |
1479 | __func__, policy->cpu, old_freq, policy->cur); | |
d3916691 VK |
1480 | } |
1481 | } | |
1482 | ||
194d99c7 | 1483 | if (new_policy) { |
d9612a49 | 1484 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1485 | if (ret) |
d417e069 | 1486 | goto out_destroy_policy; |
1aefc75b RW |
1487 | |
1488 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1489 | |
988bed09 VK |
1490 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1491 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1492 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
c17495b0 VK |
1493 | |
1494 | /* | |
1495 | * Register with the energy model before | |
1496 | * sched_cpufreq_governor_change() is called, which will result | |
1497 | * in rebuilding of the sched domains, which should only be done | |
1498 | * once the energy model is properly initialized for the policy | |
1499 | * first. | |
1500 | * | |
1501 | * Also, this should be called before the policy is registered | |
1502 | * with cooling framework. | |
1503 | */ | |
1504 | if (cpufreq_driver->register_em) | |
1505 | cpufreq_driver->register_em(policy); | |
988bed09 | 1506 | } |
9515f4d6 | 1507 | |
7f0fa40f VK |
1508 | ret = cpufreq_init_policy(policy); |
1509 | if (ret) { | |
1510 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1511 | __func__, cpu, ret); | |
d417e069 | 1512 | goto out_destroy_policy; |
08fd8c1c | 1513 | } |
e18f1682 | 1514 | |
4e97b631 | 1515 | up_write(&policy->rwsem); |
08fd8c1c | 1516 | |
038c5b3e | 1517 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1518 | |
bcc61569 | 1519 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1520 | policy->cdev = of_cpufreq_cooling_register(policy); |
1521 | ||
2d06d8c4 | 1522 | pr_debug("initialization complete\n"); |
87c32271 | 1523 | |
1da177e4 LT |
1524 | return 0; |
1525 | ||
d417e069 | 1526 | out_destroy_policy: |
b24b6478 VK |
1527 | for_each_cpu(j, policy->real_cpus) |
1528 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1529 | ||
7106e02b PB |
1530 | up_write(&policy->rwsem); |
1531 | ||
3b718057 RW |
1532 | out_offline_policy: |
1533 | if (cpufreq_driver->offline) | |
1534 | cpufreq_driver->offline(policy); | |
1535 | ||
d417e069 | 1536 | out_exit_policy: |
da60ce9f VK |
1537 | if (cpufreq_driver->exit) |
1538 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1539 | |
8101f997 | 1540 | out_free_policy: |
f9f41e3e | 1541 | cpufreq_policy_free(policy); |
1da177e4 LT |
1542 | return ret; |
1543 | } | |
1544 | ||
0b275352 RW |
1545 | /** |
1546 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1547 | * @dev: CPU device. | |
1548 | * @sif: Subsystem interface structure pointer (not used) | |
1549 | */ | |
1550 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1551 | { | |
a794d613 | 1552 | struct cpufreq_policy *policy; |
0b275352 | 1553 | unsigned cpu = dev->id; |
26619804 | 1554 | int ret; |
0b275352 RW |
1555 | |
1556 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1557 | ||
26619804 VK |
1558 | if (cpu_online(cpu)) { |
1559 | ret = cpufreq_online(cpu); | |
1560 | if (ret) | |
1561 | return ret; | |
1562 | } | |
0b275352 | 1563 | |
26619804 | 1564 | /* Create sysfs link on CPU registration */ |
a794d613 | 1565 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 | 1566 | if (policy) |
2da3e586 | 1567 | add_cpu_dev_symlink(policy, cpu, dev); |
26619804 | 1568 | |
2f0ba790 | 1569 | return 0; |
1da177e4 LT |
1570 | } |
1571 | ||
27622b06 | 1572 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1573 | { |
3a3e9e06 | 1574 | struct cpufreq_policy *policy; |
69cee714 | 1575 | int ret; |
1da177e4 | 1576 | |
b8eed8af | 1577 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1578 | |
988bed09 | 1579 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1580 | if (!policy) { |
b8eed8af | 1581 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1582 | return 0; |
1da177e4 | 1583 | } |
1da177e4 | 1584 | |
49f18560 | 1585 | down_write(&policy->rwsem); |
45482c70 RW |
1586 | if (has_target()) |
1587 | cpufreq_stop_governor(policy); | |
1da177e4 | 1588 | |
9591becb | 1589 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1590 | |
9591becb VK |
1591 | if (policy_is_inactive(policy)) { |
1592 | if (has_target()) | |
1593 | strncpy(policy->last_governor, policy->governor->name, | |
1594 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1595 | else |
1596 | policy->last_policy = policy->policy; | |
9591becb VK |
1597 | } else if (cpu == policy->cpu) { |
1598 | /* Nominate new CPU */ | |
1599 | policy->cpu = cpumask_any(policy->cpus); | |
1600 | } | |
084f3493 | 1601 | |
9591becb VK |
1602 | /* Start governor again for active policy */ |
1603 | if (!policy_is_inactive(policy)) { | |
1604 | if (has_target()) { | |
0a300767 | 1605 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1606 | if (ret) |
1607 | pr_err("%s: Failed to start governor\n", __func__); | |
1608 | } | |
cedb70af | 1609 | |
49f18560 | 1610 | goto unlock; |
cedb70af SB |
1611 | } |
1612 | ||
bcc61569 | 1613 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1614 | cpufreq_cooling_unregister(policy->cdev); |
1615 | policy->cdev = NULL; | |
1616 | } | |
1617 | ||
36be3418 RW |
1618 | if (has_target()) |
1619 | cpufreq_exit_governor(policy); | |
1da177e4 | 1620 | |
87549141 | 1621 | /* |
91a12e91 VK |
1622 | * Perform the ->offline() during light-weight tear-down, as |
1623 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1624 | */ |
91a12e91 VK |
1625 | if (cpufreq_driver->offline) { |
1626 | cpufreq_driver->offline(policy); | |
1627 | } else if (cpufreq_driver->exit) { | |
87549141 | 1628 | cpufreq_driver->exit(policy); |
55582bcc SP |
1629 | policy->freq_table = NULL; |
1630 | } | |
49f18560 VK |
1631 | |
1632 | unlock: | |
1633 | up_write(&policy->rwsem); | |
27622b06 | 1634 | return 0; |
1da177e4 LT |
1635 | } |
1636 | ||
a9909c21 | 1637 | /* |
27a862e9 | 1638 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1639 | * |
1640 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1641 | */ |
71db87ba | 1642 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1643 | { |
8a25a2fd | 1644 | unsigned int cpu = dev->id; |
559ed407 | 1645 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1646 | |
559ed407 | 1647 | if (!policy) |
1af115d6 | 1648 | return; |
87549141 | 1649 | |
69cee714 VK |
1650 | if (cpu_online(cpu)) |
1651 | cpufreq_offline(cpu); | |
87549141 | 1652 | |
559ed407 | 1653 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1654 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1655 | |
91a12e91 VK |
1656 | if (cpumask_empty(policy->real_cpus)) { |
1657 | /* We did light-weight exit earlier, do full tear down now */ | |
1658 | if (cpufreq_driver->offline) | |
1659 | cpufreq_driver->exit(policy); | |
1660 | ||
f9f41e3e | 1661 | cpufreq_policy_free(policy); |
91a12e91 | 1662 | } |
5a01f2e8 VP |
1663 | } |
1664 | ||
1da177e4 | 1665 | /** |
ec06e586 RW |
1666 | * cpufreq_out_of_sync - Fix up actual and saved CPU frequency difference. |
1667 | * @policy: Policy managing CPUs. | |
1668 | * @new_freq: New CPU frequency. | |
1da177e4 | 1669 | * |
ec06e586 RW |
1670 | * Adjust to the current frequency first and clean up later by either calling |
1671 | * cpufreq_update_policy(), or scheduling handle_update(). | |
1da177e4 | 1672 | */ |
a1e1dc41 | 1673 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1674 | unsigned int new_freq) |
1da177e4 LT |
1675 | { |
1676 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1677 | |
e837f9b5 | 1678 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1679 | policy->cur, new_freq); |
1da177e4 | 1680 | |
a1e1dc41 | 1681 | freqs.old = policy->cur; |
1da177e4 | 1682 | freqs.new = new_freq; |
b43a7ffb | 1683 | |
8fec051e VK |
1684 | cpufreq_freq_transition_begin(policy, &freqs); |
1685 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1686 | } |
1687 | ||
5980752e VK |
1688 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1689 | { | |
1690 | unsigned int new_freq; | |
1691 | ||
1692 | new_freq = cpufreq_driver->get(policy->cpu); | |
1693 | if (!new_freq) | |
1694 | return 0; | |
1695 | ||
1696 | /* | |
1697 | * If fast frequency switching is used with the given policy, the check | |
1698 | * against policy->cur is pointless, so skip it in that case. | |
1699 | */ | |
1700 | if (policy->fast_switch_enabled || !has_target()) | |
1701 | return new_freq; | |
1702 | ||
1703 | if (policy->cur != new_freq) { | |
1704 | cpufreq_out_of_sync(policy, new_freq); | |
1705 | if (update) | |
1706 | schedule_work(&policy->update); | |
1707 | } | |
1708 | ||
1709 | return new_freq; | |
1710 | } | |
1711 | ||
32ee8c3e | 1712 | /** |
4ab70df4 | 1713 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1714 | * @cpu: CPU number |
1715 | * | |
1716 | * This is the last known freq, without actually getting it from the driver. | |
1717 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1718 | */ | |
1719 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1720 | { | |
9e21ba8b | 1721 | struct cpufreq_policy *policy; |
e08f5f5b | 1722 | unsigned int ret_freq = 0; |
c75361c0 | 1723 | unsigned long flags; |
95235ca2 | 1724 | |
c75361c0 RC |
1725 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1726 | ||
1727 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1728 | ret_freq = cpufreq_driver->get(cpu); | |
1729 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1730 | return ret_freq; | |
1731 | } | |
1732 | ||
1733 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1734 | |
1735 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1736 | if (policy) { |
e08f5f5b | 1737 | ret_freq = policy->cur; |
95235ca2 VP |
1738 | cpufreq_cpu_put(policy); |
1739 | } | |
1740 | ||
4d34a67d | 1741 | return ret_freq; |
95235ca2 VP |
1742 | } |
1743 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1744 | ||
3d737108 JB |
1745 | /** |
1746 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1747 | * @cpu: CPU number | |
1748 | * | |
1749 | * Just return the max possible frequency for a given CPU. | |
1750 | */ | |
1751 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1752 | { | |
1753 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1754 | unsigned int ret_freq = 0; | |
1755 | ||
1756 | if (policy) { | |
1757 | ret_freq = policy->max; | |
1758 | cpufreq_cpu_put(policy); | |
1759 | } | |
1760 | ||
1761 | return ret_freq; | |
1762 | } | |
1763 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1764 | ||
bbce8eaa IV |
1765 | /** |
1766 | * cpufreq_get_hw_max_freq - get the max hardware frequency of the CPU | |
1767 | * @cpu: CPU number | |
1768 | * | |
1769 | * The default return value is the max_freq field of cpuinfo. | |
1770 | */ | |
1771 | __weak unsigned int cpufreq_get_hw_max_freq(unsigned int cpu) | |
1772 | { | |
1773 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1774 | unsigned int ret_freq = 0; | |
1775 | ||
1776 | if (policy) { | |
1777 | ret_freq = policy->cpuinfo.max_freq; | |
1778 | cpufreq_cpu_put(policy); | |
1779 | } | |
1780 | ||
1781 | return ret_freq; | |
1782 | } | |
1783 | EXPORT_SYMBOL(cpufreq_get_hw_max_freq); | |
1784 | ||
d92d50a4 | 1785 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1786 | { |
4db7c34c | 1787 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1788 | return 0; |
1da177e4 | 1789 | |
5980752e | 1790 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1791 | } |
1da177e4 | 1792 | |
5a01f2e8 VP |
1793 | /** |
1794 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1795 | * @cpu: CPU number | |
1796 | * | |
1797 | * Get the CPU current (static) CPU frequency | |
1798 | */ | |
1799 | unsigned int cpufreq_get(unsigned int cpu) | |
1800 | { | |
999976e0 | 1801 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1802 | unsigned int ret_freq = 0; |
5a01f2e8 | 1803 | |
999976e0 AP |
1804 | if (policy) { |
1805 | down_read(&policy->rwsem); | |
4db7c34c YH |
1806 | if (cpufreq_driver->get) |
1807 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1808 | up_read(&policy->rwsem); |
5a01f2e8 | 1809 | |
999976e0 AP |
1810 | cpufreq_cpu_put(policy); |
1811 | } | |
6eed9404 | 1812 | |
4d34a67d | 1813 | return ret_freq; |
1da177e4 LT |
1814 | } |
1815 | EXPORT_SYMBOL(cpufreq_get); | |
1816 | ||
8a25a2fd KS |
1817 | static struct subsys_interface cpufreq_interface = { |
1818 | .name = "cpufreq", | |
1819 | .subsys = &cpu_subsys, | |
1820 | .add_dev = cpufreq_add_dev, | |
1821 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1822 | }; |
1823 | ||
e28867ea VK |
1824 | /* |
1825 | * In case platform wants some specific frequency to be configured | |
1826 | * during suspend.. | |
1827 | */ | |
1828 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1829 | { | |
1830 | int ret; | |
1831 | ||
1832 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1833 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1834 | return 0; | |
e28867ea VK |
1835 | } |
1836 | ||
1837 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1838 | policy->suspend_freq); | |
1839 | ||
1840 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1841 | CPUFREQ_RELATION_H); | |
1842 | if (ret) | |
1843 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1844 | __func__, policy->suspend_freq, ret); | |
1845 | ||
1846 | return ret; | |
1847 | } | |
1848 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1849 | ||
42d4dc3f | 1850 | /** |
ec06e586 | 1851 | * cpufreq_suspend() - Suspend CPUFreq governors. |
e00e56df | 1852 | * |
2f0aea93 VK |
1853 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1854 | * as some platforms can't change frequency after this point in suspend cycle. | |
1855 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1856 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1857 | */ |
2f0aea93 | 1858 | void cpufreq_suspend(void) |
42d4dc3f | 1859 | { |
3a3e9e06 | 1860 | struct cpufreq_policy *policy; |
42d4dc3f | 1861 | |
2f0aea93 VK |
1862 | if (!cpufreq_driver) |
1863 | return; | |
42d4dc3f | 1864 | |
ba41e1bc | 1865 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1866 | goto suspend; |
42d4dc3f | 1867 | |
2f0aea93 VK |
1868 | pr_debug("%s: Suspending Governors\n", __func__); |
1869 | ||
f963735a | 1870 | for_each_active_policy(policy) { |
ba41e1bc RW |
1871 | if (has_target()) { |
1872 | down_write(&policy->rwsem); | |
45482c70 | 1873 | cpufreq_stop_governor(policy); |
ba41e1bc | 1874 | up_write(&policy->rwsem); |
ba41e1bc RW |
1875 | } |
1876 | ||
1877 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1878 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1879 | cpufreq_driver->name); | |
42d4dc3f | 1880 | } |
b1b12bab VK |
1881 | |
1882 | suspend: | |
1883 | cpufreq_suspended = true; | |
42d4dc3f BH |
1884 | } |
1885 | ||
1da177e4 | 1886 | /** |
ec06e586 | 1887 | * cpufreq_resume() - Resume CPUFreq governors. |
1da177e4 | 1888 | * |
2f0aea93 VK |
1889 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1890 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1891 | */ |
2f0aea93 | 1892 | void cpufreq_resume(void) |
1da177e4 | 1893 | { |
3a3e9e06 | 1894 | struct cpufreq_policy *policy; |
49f18560 | 1895 | int ret; |
1da177e4 | 1896 | |
2f0aea93 | 1897 | if (!cpufreq_driver) |
703cbaa6 BY |
1898 | return; |
1899 | ||
1900 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1901 | return; |
1da177e4 | 1902 | |
8e30444e LT |
1903 | cpufreq_suspended = false; |
1904 | ||
ba41e1bc | 1905 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1906 | return; |
1da177e4 | 1907 | |
2f0aea93 | 1908 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1909 | |
f963735a | 1910 | for_each_active_policy(policy) { |
49f18560 | 1911 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1912 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1913 | policy); | |
ba41e1bc | 1914 | } else if (has_target()) { |
49f18560 | 1915 | down_write(&policy->rwsem); |
0a300767 | 1916 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1917 | up_write(&policy->rwsem); |
1918 | ||
1919 | if (ret) | |
1920 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1921 | __func__, policy); | |
1922 | } | |
2f0aea93 VK |
1923 | } |
1924 | } | |
1da177e4 | 1925 | |
a62f68f5 RW |
1926 | /** |
1927 | * cpufreq_driver_test_flags - Test cpufreq driver's flags against given ones. | |
1928 | * @flags: Flags to test against the current cpufreq driver's flags. | |
1929 | * | |
1930 | * Assumes that the driver is there, so callers must ensure that this is the | |
1931 | * case. | |
1932 | */ | |
1933 | bool cpufreq_driver_test_flags(u16 flags) | |
1934 | { | |
1935 | return !!(cpufreq_driver->flags & flags); | |
1936 | } | |
1937 | ||
9d95046e | 1938 | /** |
ec06e586 | 1939 | * cpufreq_get_current_driver - Return the current driver's name. |
9d95046e | 1940 | * |
ec06e586 RW |
1941 | * Return the name string of the currently registered cpufreq driver or NULL if |
1942 | * none. | |
9d95046e BP |
1943 | */ |
1944 | const char *cpufreq_get_current_driver(void) | |
1945 | { | |
1c3d85dd RW |
1946 | if (cpufreq_driver) |
1947 | return cpufreq_driver->name; | |
1948 | ||
1949 | return NULL; | |
9d95046e BP |
1950 | } |
1951 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1952 | |
51315cdf | 1953 | /** |
ec06e586 | 1954 | * cpufreq_get_driver_data - Return current driver data. |
51315cdf | 1955 | * |
ec06e586 RW |
1956 | * Return the private data of the currently registered cpufreq driver, or NULL |
1957 | * if no cpufreq driver has been registered. | |
51315cdf TP |
1958 | */ |
1959 | void *cpufreq_get_driver_data(void) | |
1960 | { | |
1961 | if (cpufreq_driver) | |
1962 | return cpufreq_driver->driver_data; | |
1963 | ||
1964 | return NULL; | |
1965 | } | |
1966 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1967 | ||
1da177e4 LT |
1968 | /********************************************************************* |
1969 | * NOTIFIER LISTS INTERFACE * | |
1970 | *********************************************************************/ | |
1971 | ||
1972 | /** | |
ec06e586 RW |
1973 | * cpufreq_register_notifier - Register a notifier with cpufreq. |
1974 | * @nb: notifier function to register. | |
1975 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 1976 | * |
ec06e586 RW |
1977 | * Add a notifier to one of two lists: either a list of notifiers that run on |
1978 | * clock rate changes (once before and once after every transition), or a list | |
1979 | * of notifiers that ron on cpufreq policy changes. | |
1da177e4 | 1980 | * |
ec06e586 RW |
1981 | * This function may sleep and it has the same return values as |
1982 | * blocking_notifier_chain_register(). | |
1da177e4 LT |
1983 | */ |
1984 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1985 | { | |
1986 | int ret; | |
1987 | ||
d5aaffa9 DB |
1988 | if (cpufreq_disabled()) |
1989 | return -EINVAL; | |
1990 | ||
1da177e4 LT |
1991 | switch (list) { |
1992 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1993 | mutex_lock(&cpufreq_fast_switch_lock); |
1994 | ||
1995 | if (cpufreq_fast_switch_count > 0) { | |
1996 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1997 | return -EBUSY; | |
1998 | } | |
b4dfdbb3 | 1999 | ret = srcu_notifier_chain_register( |
e041c683 | 2000 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2001 | if (!ret) |
2002 | cpufreq_fast_switch_count--; | |
2003 | ||
2004 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2005 | break; |
2006 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2007 | ret = blocking_notifier_chain_register( |
2008 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2009 | break; |
2010 | default: | |
2011 | ret = -EINVAL; | |
2012 | } | |
1da177e4 LT |
2013 | |
2014 | return ret; | |
2015 | } | |
2016 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
2017 | ||
1da177e4 | 2018 | /** |
ec06e586 RW |
2019 | * cpufreq_unregister_notifier - Unregister a notifier from cpufreq. |
2020 | * @nb: notifier block to be unregistered. | |
2021 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 2022 | * |
ec06e586 | 2023 | * Remove a notifier from one of the cpufreq notifier lists. |
1da177e4 | 2024 | * |
ec06e586 RW |
2025 | * This function may sleep and it has the same return values as |
2026 | * blocking_notifier_chain_unregister(). | |
1da177e4 LT |
2027 | */ |
2028 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
2029 | { | |
2030 | int ret; | |
2031 | ||
d5aaffa9 DB |
2032 | if (cpufreq_disabled()) |
2033 | return -EINVAL; | |
2034 | ||
1da177e4 LT |
2035 | switch (list) { |
2036 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
2037 | mutex_lock(&cpufreq_fast_switch_lock); |
2038 | ||
b4dfdbb3 | 2039 | ret = srcu_notifier_chain_unregister( |
e041c683 | 2040 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2041 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
2042 | cpufreq_fast_switch_count++; | |
2043 | ||
2044 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2045 | break; |
2046 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2047 | ret = blocking_notifier_chain_unregister( |
2048 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2049 | break; |
2050 | default: | |
2051 | ret = -EINVAL; | |
2052 | } | |
1da177e4 LT |
2053 | |
2054 | return ret; | |
2055 | } | |
2056 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
2057 | ||
2058 | ||
2059 | /********************************************************************* | |
2060 | * GOVERNORS * | |
2061 | *********************************************************************/ | |
2062 | ||
b7898fda RW |
2063 | /** |
2064 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
2065 | * @policy: cpufreq policy to switch the frequency for. | |
2066 | * @target_freq: New frequency to set (may be approximate). | |
2067 | * | |
2068 | * Carry out a fast frequency switch without sleeping. | |
2069 | * | |
2070 | * The driver's ->fast_switch() callback invoked by this function must be | |
2071 | * suitable for being called from within RCU-sched read-side critical sections | |
2072 | * and it is expected to select the minimum available frequency greater than or | |
2073 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2074 | * | |
2075 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2076 | * | |
2077 | * Governors calling this function must guarantee that it will never be invoked | |
2078 | * twice in parallel for the same policy and that it will never be called in | |
2079 | * parallel with either ->target() or ->target_index() for the same policy. | |
2080 | * | |
209887e6 VK |
2081 | * Returns the actual frequency set for the CPU. |
2082 | * | |
2083 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2084 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2085 | */ |
2086 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2087 | unsigned int target_freq) | |
2088 | { | |
1a0419b0 | 2089 | unsigned int freq; |
08d8c65e | 2090 | int cpu; |
1a0419b0 | 2091 | |
b9af6948 | 2092 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
1a0419b0 IV |
2093 | freq = cpufreq_driver->fast_switch(policy, target_freq); |
2094 | ||
96f60cdd VK |
2095 | if (!freq) |
2096 | return 0; | |
2097 | ||
08d8c65e | 2098 | policy->cur = freq; |
1a0419b0 IV |
2099 | arch_set_freq_scale(policy->related_cpus, freq, |
2100 | policy->cpuinfo.max_freq); | |
96f60cdd | 2101 | cpufreq_stats_record_transition(policy, freq); |
b7898fda | 2102 | |
08d8c65e VK |
2103 | if (trace_cpu_frequency_enabled()) { |
2104 | for_each_cpu(cpu, policy->cpus) | |
2105 | trace_cpu_frequency(freq, cpu); | |
2106 | } | |
2107 | ||
1a0419b0 | 2108 | return freq; |
b7898fda RW |
2109 | } |
2110 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2111 | ||
ee2cc427 RW |
2112 | /** |
2113 | * cpufreq_driver_adjust_perf - Adjust CPU performance level in one go. | |
2114 | * @cpu: Target CPU. | |
2115 | * @min_perf: Minimum (required) performance level (units of @capacity). | |
4e6df217 | 2116 | * @target_perf: Target (desired) performance level (units of @capacity). |
ee2cc427 RW |
2117 | * @capacity: Capacity of the target CPU. |
2118 | * | |
2119 | * Carry out a fast performance level switch of @cpu without sleeping. | |
2120 | * | |
2121 | * The driver's ->adjust_perf() callback invoked by this function must be | |
2122 | * suitable for being called from within RCU-sched read-side critical sections | |
2123 | * and it is expected to select a suitable performance level equal to or above | |
2124 | * @min_perf and preferably equal to or below @target_perf. | |
2125 | * | |
2126 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2127 | * | |
2128 | * Governors calling this function must guarantee that it will never be invoked | |
2129 | * twice in parallel for the same CPU and that it will never be called in | |
2130 | * parallel with either ->target() or ->target_index() or ->fast_switch() for | |
2131 | * the same CPU. | |
2132 | */ | |
2133 | void cpufreq_driver_adjust_perf(unsigned int cpu, | |
2134 | unsigned long min_perf, | |
2135 | unsigned long target_perf, | |
2136 | unsigned long capacity) | |
2137 | { | |
2138 | cpufreq_driver->adjust_perf(cpu, min_perf, target_perf, capacity); | |
2139 | } | |
2140 | ||
2141 | /** | |
2142 | * cpufreq_driver_has_adjust_perf - Check "direct fast switch" callback. | |
2143 | * | |
2144 | * Return 'true' if the ->adjust_perf callback is present for the | |
2145 | * current driver or 'false' otherwise. | |
2146 | */ | |
2147 | bool cpufreq_driver_has_adjust_perf(void) | |
2148 | { | |
2149 | return !!cpufreq_driver->adjust_perf; | |
2150 | } | |
2151 | ||
1c03a2d0 VK |
2152 | /* Must set freqs->new to intermediate frequency */ |
2153 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2154 | struct cpufreq_freqs *freqs, int index) | |
2155 | { | |
2156 | int ret; | |
2157 | ||
2158 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2159 | ||
2160 | /* We don't need to switch to intermediate freq */ | |
2161 | if (!freqs->new) | |
2162 | return 0; | |
2163 | ||
2164 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2165 | __func__, policy->cpu, freqs->old, freqs->new); | |
2166 | ||
2167 | cpufreq_freq_transition_begin(policy, freqs); | |
2168 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2169 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2170 | ||
2171 | if (ret) | |
2172 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2173 | __func__, ret); | |
2174 | ||
2175 | return ret; | |
2176 | } | |
2177 | ||
23727845 | 2178 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2179 | { |
1c03a2d0 | 2180 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
56a7ff75 | 2181 | unsigned int restore_freq, intermediate_freq = 0; |
23727845 | 2182 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2183 | int retval = -EINVAL; |
2184 | bool notify; | |
2185 | ||
23727845 VK |
2186 | if (newfreq == policy->cur) |
2187 | return 0; | |
2188 | ||
56a7ff75 RW |
2189 | /* Save last value to restore later on errors */ |
2190 | restore_freq = policy->cur; | |
2191 | ||
8d65775d | 2192 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2193 | if (notify) { |
1c03a2d0 VK |
2194 | /* Handle switching to intermediate frequency */ |
2195 | if (cpufreq_driver->get_intermediate) { | |
2196 | retval = __target_intermediate(policy, &freqs, index); | |
2197 | if (retval) | |
2198 | return retval; | |
2199 | ||
2200 | intermediate_freq = freqs.new; | |
2201 | /* Set old freq to intermediate */ | |
2202 | if (intermediate_freq) | |
2203 | freqs.old = freqs.new; | |
2204 | } | |
8d65775d | 2205 | |
23727845 | 2206 | freqs.new = newfreq; |
8d65775d VK |
2207 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2208 | __func__, policy->cpu, freqs.old, freqs.new); | |
2209 | ||
2210 | cpufreq_freq_transition_begin(policy, &freqs); | |
2211 | } | |
2212 | ||
2213 | retval = cpufreq_driver->target_index(policy, index); | |
2214 | if (retval) | |
2215 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2216 | retval); | |
2217 | ||
1c03a2d0 | 2218 | if (notify) { |
8d65775d VK |
2219 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2220 | ||
1c03a2d0 VK |
2221 | /* |
2222 | * Failed after setting to intermediate freq? Driver should have | |
2223 | * reverted back to initial frequency and so should we. Check | |
2224 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2225 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2226 | */ |
2227 | if (unlikely(retval && intermediate_freq)) { | |
2228 | freqs.old = intermediate_freq; | |
56a7ff75 | 2229 | freqs.new = restore_freq; |
1c03a2d0 VK |
2230 | cpufreq_freq_transition_begin(policy, &freqs); |
2231 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2232 | } | |
2233 | } | |
2234 | ||
8d65775d VK |
2235 | return retval; |
2236 | } | |
2237 | ||
1da177e4 LT |
2238 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2239 | unsigned int target_freq, | |
2240 | unsigned int relation) | |
2241 | { | |
7249924e | 2242 | unsigned int old_target_freq = target_freq; |
c32b6b8e | 2243 | |
a7b422cd KRW |
2244 | if (cpufreq_disabled()) |
2245 | return -ENODEV; | |
2246 | ||
f9ccdec2 | 2247 | target_freq = __resolve_freq(policy, target_freq, relation); |
7249924e VK |
2248 | |
2249 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2250 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2251 | |
9c0ebcf7 VK |
2252 | /* |
2253 | * This might look like a redundant call as we are checking it again | |
2254 | * after finding index. But it is left intentionally for cases where | |
2255 | * exactly same freq is called again and so we can save on few function | |
2256 | * calls. | |
2257 | */ | |
1c534352 RW |
2258 | if (target_freq == policy->cur && |
2259 | !(cpufreq_driver->flags & CPUFREQ_NEED_UPDATE_LIMITS)) | |
5a1c0228 VK |
2260 | return 0; |
2261 | ||
1c3d85dd | 2262 | if (cpufreq_driver->target) |
6019d23a | 2263 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 2264 | |
6019d23a RW |
2265 | if (!cpufreq_driver->target_index) |
2266 | return -EINVAL; | |
9c0ebcf7 | 2267 | |
f9ccdec2 | 2268 | return __target_index(policy, policy->cached_resolved_idx); |
1da177e4 LT |
2269 | } |
2270 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2271 | ||
1da177e4 LT |
2272 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2273 | unsigned int target_freq, | |
2274 | unsigned int relation) | |
2275 | { | |
62c23a89 | 2276 | int ret; |
1da177e4 | 2277 | |
ad7722da | 2278 | down_write(&policy->rwsem); |
1da177e4 LT |
2279 | |
2280 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2281 | ||
ad7722da | 2282 | up_write(&policy->rwsem); |
1da177e4 | 2283 | |
1da177e4 LT |
2284 | return ret; |
2285 | } | |
2286 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2287 | ||
de1df26b RW |
2288 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2289 | { | |
2290 | return NULL; | |
2291 | } | |
2292 | ||
a92604b4 | 2293 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2294 | { |
cc993cab | 2295 | int ret; |
6afde10c | 2296 | |
2f0aea93 VK |
2297 | /* Don't start any governor operations if we are entering suspend */ |
2298 | if (cpufreq_suspended) | |
2299 | return 0; | |
cb57720b EZ |
2300 | /* |
2301 | * Governor might not be initiated here if ACPI _PPC changed | |
2302 | * notification happened, so check it. | |
2303 | */ | |
2304 | if (!policy->governor) | |
2305 | return -EINVAL; | |
2f0aea93 | 2306 | |
ed4676e2 | 2307 | /* Platform doesn't want dynamic frequency switching ? */ |
9a2a9ebc | 2308 | if (policy->governor->flags & CPUFREQ_GOV_DYNAMIC_SWITCHING && |
fc4c709f | 2309 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2310 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2311 | ||
2312 | if (gov) { | |
fe829ed8 | 2313 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2314 | policy->governor->name, gov->name); |
6afde10c | 2315 | policy->governor = gov; |
de1df26b RW |
2316 | } else { |
2317 | return -EINVAL; | |
6afde10c | 2318 | } |
1c256245 | 2319 | } |
1da177e4 | 2320 | |
a92604b4 RW |
2321 | if (!try_module_get(policy->governor->owner)) |
2322 | return -EINVAL; | |
95731ebb | 2323 | |
a92604b4 | 2324 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2325 | |
e788892b RW |
2326 | if (policy->governor->init) { |
2327 | ret = policy->governor->init(policy); | |
2328 | if (ret) { | |
36be3418 | 2329 | module_put(policy->governor->owner); |
e788892b RW |
2330 | return ret; |
2331 | } | |
36be3418 | 2332 | } |
1da177e4 | 2333 | |
ea9364bb RW |
2334 | policy->strict_target = !!(policy->governor->flags & CPUFREQ_GOV_STRICT_TARGET); |
2335 | ||
a92604b4 RW |
2336 | return 0; |
2337 | } | |
2338 | ||
2339 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2340 | { | |
2341 | if (cpufreq_suspended || !policy->governor) | |
2342 | return; | |
2343 | ||
2344 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2345 | ||
e788892b RW |
2346 | if (policy->governor->exit) |
2347 | policy->governor->exit(policy); | |
a92604b4 | 2348 | |
a92604b4 | 2349 | module_put(policy->governor->owner); |
1da177e4 LT |
2350 | } |
2351 | ||
f6ebbcf0 | 2352 | int cpufreq_start_governor(struct cpufreq_policy *policy) |
0a300767 RW |
2353 | { |
2354 | int ret; | |
2355 | ||
a92604b4 RW |
2356 | if (cpufreq_suspended) |
2357 | return 0; | |
2358 | ||
2359 | if (!policy->governor) | |
2360 | return -EINVAL; | |
2361 | ||
2362 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2363 | ||
407d0fff | 2364 | if (cpufreq_driver->get) |
5980752e | 2365 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2366 | |
e788892b RW |
2367 | if (policy->governor->start) { |
2368 | ret = policy->governor->start(policy); | |
2369 | if (ret) | |
2370 | return ret; | |
2371 | } | |
2372 | ||
2373 | if (policy->governor->limits) | |
2374 | policy->governor->limits(policy); | |
d6ff44d6 | 2375 | |
d6ff44d6 | 2376 | return 0; |
0a300767 RW |
2377 | } |
2378 | ||
f6ebbcf0 | 2379 | void cpufreq_stop_governor(struct cpufreq_policy *policy) |
a92604b4 RW |
2380 | { |
2381 | if (cpufreq_suspended || !policy->governor) | |
2382 | return; | |
2383 | ||
2384 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2385 | ||
e788892b RW |
2386 | if (policy->governor->stop) |
2387 | policy->governor->stop(policy); | |
a92604b4 RW |
2388 | } |
2389 | ||
2390 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2391 | { | |
2392 | if (cpufreq_suspended || !policy->governor) | |
2393 | return; | |
2394 | ||
2395 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2396 | ||
e788892b RW |
2397 | if (policy->governor->limits) |
2398 | policy->governor->limits(policy); | |
0a300767 RW |
2399 | } |
2400 | ||
1da177e4 LT |
2401 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2402 | { | |
3bcb09a3 | 2403 | int err; |
1da177e4 LT |
2404 | |
2405 | if (!governor) | |
2406 | return -EINVAL; | |
2407 | ||
a7b422cd KRW |
2408 | if (cpufreq_disabled()) |
2409 | return -ENODEV; | |
2410 | ||
3fc54d37 | 2411 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2412 | |
3bcb09a3 | 2413 | err = -EBUSY; |
42f91fa1 | 2414 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2415 | err = 0; |
2416 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2417 | } |
1da177e4 | 2418 | |
32ee8c3e | 2419 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2420 | return err; |
1da177e4 LT |
2421 | } |
2422 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2423 | ||
1da177e4 LT |
2424 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2425 | { | |
4573237b VK |
2426 | struct cpufreq_policy *policy; |
2427 | unsigned long flags; | |
90e41bac | 2428 | |
1da177e4 LT |
2429 | if (!governor) |
2430 | return; | |
2431 | ||
a7b422cd KRW |
2432 | if (cpufreq_disabled()) |
2433 | return; | |
2434 | ||
4573237b VK |
2435 | /* clear last_governor for all inactive policies */ |
2436 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2437 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2438 | if (!strcmp(policy->last_governor, governor->name)) { |
2439 | policy->governor = NULL; | |
4573237b | 2440 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2441 | } |
90e41bac | 2442 | } |
4573237b | 2443 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2444 | |
3fc54d37 | 2445 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2446 | list_del(&governor->governor_list); |
3fc54d37 | 2447 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2448 | } |
2449 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2450 | ||
2451 | ||
1da177e4 LT |
2452 | /********************************************************************* |
2453 | * POLICY INTERFACE * | |
2454 | *********************************************************************/ | |
2455 | ||
2456 | /** | |
2457 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2458 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2459 | * is written | |
a9909c21 | 2460 | * @cpu: CPU to find the policy for |
1da177e4 LT |
2461 | * |
2462 | * Reads the current cpufreq policy. | |
2463 | */ | |
2464 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2465 | { | |
2466 | struct cpufreq_policy *cpu_policy; | |
2467 | if (!policy) | |
2468 | return -EINVAL; | |
2469 | ||
2470 | cpu_policy = cpufreq_cpu_get(cpu); | |
2471 | if (!cpu_policy) | |
2472 | return -EINVAL; | |
2473 | ||
d5b73cd8 | 2474 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2475 | |
2476 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2477 | return 0; |
2478 | } | |
2479 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2480 | ||
a0dbb819 RW |
2481 | /** |
2482 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2483 | * @policy: Policy object to modify. | |
1e4f63ae RW |
2484 | * @new_gov: Policy governor pointer. |
2485 | * @new_pol: Policy value (for drivers with built-in governors). | |
a0dbb819 | 2486 | * |
1e4f63ae RW |
2487 | * Invoke the cpufreq driver's ->verify() callback to sanity-check the frequency |
2488 | * limits to be set for the policy, update @policy with the verified limits | |
2489 | * values and either invoke the driver's ->setpolicy() callback (if present) or | |
2490 | * carry out a governor update for @policy. That is, run the current governor's | |
2491 | * ->limits() callback (if @new_gov points to the same object as the one in | |
2492 | * @policy) or replace the governor for @policy with @new_gov. | |
a0dbb819 RW |
2493 | * |
2494 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2495 | */ |
1e4f63ae RW |
2496 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
2497 | struct cpufreq_governor *new_gov, | |
2498 | unsigned int new_pol) | |
1da177e4 | 2499 | { |
1e4f63ae | 2500 | struct cpufreq_policy_data new_data; |
d9a789c7 RW |
2501 | struct cpufreq_governor *old_gov; |
2502 | int ret; | |
1da177e4 | 2503 | |
1e4f63ae RW |
2504 | memcpy(&new_data.cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
2505 | new_data.freq_table = policy->freq_table; | |
2506 | new_data.cpu = policy->cpu; | |
fba9573b | 2507 | /* |
67d874c3 VK |
2508 | * PM QoS framework collects all the requests from users and provide us |
2509 | * the final aggregated value here. | |
2510 | */ | |
1e4f63ae RW |
2511 | new_data.min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); |
2512 | new_data.max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); | |
2513 | ||
2514 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", | |
2515 | new_data.cpu, new_data.min, new_data.max); | |
9c9a43ed | 2516 | |
737ffb27 VK |
2517 | /* |
2518 | * Verify that the CPU speed can be set within these limits and make sure | |
2519 | * that min <= max. | |
2520 | */ | |
1e4f63ae | 2521 | ret = cpufreq_driver->verify(&new_data); |
1da177e4 | 2522 | if (ret) |
d9a789c7 | 2523 | return ret; |
1da177e4 | 2524 | |
7e4837c0 VD |
2525 | /* |
2526 | * Resolve policy min/max to available frequencies. It ensures | |
2527 | * no frequency resolution will neither overshoot the requested maximum | |
2528 | * nor undershoot the requested minimum. | |
2529 | */ | |
1e4f63ae RW |
2530 | policy->min = new_data.min; |
2531 | policy->max = new_data.max; | |
7e4837c0 VD |
2532 | policy->min = __resolve_freq(policy, policy->min, CPUFREQ_RELATION_L); |
2533 | policy->max = __resolve_freq(policy, policy->max, CPUFREQ_RELATION_H); | |
601b2185 | 2534 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2535 | |
e3c06236 SM |
2536 | policy->cached_target_freq = UINT_MAX; |
2537 | ||
2d06d8c4 | 2538 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2539 | policy->min, policy->max); |
1da177e4 | 2540 | |
1c3d85dd | 2541 | if (cpufreq_driver->setpolicy) { |
1e4f63ae | 2542 | policy->policy = new_pol; |
2d06d8c4 | 2543 | pr_debug("setting range\n"); |
167a38dc | 2544 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2545 | } |
1da177e4 | 2546 | |
1e4f63ae | 2547 | if (new_gov == policy->governor) { |
2bb4059e | 2548 | pr_debug("governor limits update\n"); |
a92604b4 | 2549 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2550 | return 0; |
0a300767 | 2551 | } |
7bd353a9 | 2552 | |
d9a789c7 RW |
2553 | pr_debug("governor switch\n"); |
2554 | ||
2555 | /* save old, working values */ | |
2556 | old_gov = policy->governor; | |
2557 | /* end old governor */ | |
2558 | if (old_gov) { | |
45482c70 | 2559 | cpufreq_stop_governor(policy); |
36be3418 | 2560 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2561 | } |
2562 | ||
d9a789c7 | 2563 | /* start new governor */ |
1e4f63ae | 2564 | policy->governor = new_gov; |
a92604b4 | 2565 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2566 | if (!ret) { |
0a300767 RW |
2567 | ret = cpufreq_start_governor(policy); |
2568 | if (!ret) { | |
2bb4059e | 2569 | pr_debug("governor change\n"); |
531b5c9f | 2570 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2571 | return 0; |
2572 | } | |
b7898fda | 2573 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2574 | } |
2575 | ||
2576 | /* new governor failed, so re-start old one */ | |
2577 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2578 | if (old_gov) { | |
2579 | policy->governor = old_gov; | |
a92604b4 | 2580 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2581 | policy->governor = NULL; |
2582 | else | |
0a300767 | 2583 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2584 | } |
2585 | ||
4bc384ae | 2586 | return ret; |
1da177e4 LT |
2587 | } |
2588 | ||
1da177e4 | 2589 | /** |
a0dbb819 RW |
2590 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2591 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2592 | * |
a0dbb819 | 2593 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2594 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2595 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2596 | * for the policy in question, among other things. | |
1da177e4 | 2597 | */ |
30248fef | 2598 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2599 | { |
540a3758 | 2600 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2601 | |
fefa8ff8 | 2602 | if (!policy) |
30248fef | 2603 | return; |
1da177e4 | 2604 | |
bb176f7d VK |
2605 | /* |
2606 | * BIOS might change freq behind our back | |
2607 | * -> ask driver for current freq and notify governors about a change | |
2608 | */ | |
5ddc6d4e | 2609 | if (cpufreq_driver->get && has_target() && |
5980752e | 2610 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2611 | goto unlock; |
30248fef | 2612 | |
70a59fde | 2613 | refresh_frequency_limits(policy); |
1da177e4 | 2614 | |
fefa8ff8 | 2615 | unlock: |
540a3758 | 2616 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2617 | } |
2618 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2619 | ||
5a25e3f7 RW |
2620 | /** |
2621 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2622 | * @cpu: CPU to update the policy limits for. | |
2623 | * | |
2624 | * Invoke the driver's ->update_limits callback if present or call | |
2625 | * cpufreq_update_policy() for @cpu. | |
2626 | */ | |
2627 | void cpufreq_update_limits(unsigned int cpu) | |
2628 | { | |
2629 | if (cpufreq_driver->update_limits) | |
2630 | cpufreq_driver->update_limits(cpu); | |
2631 | else | |
2632 | cpufreq_update_policy(cpu); | |
2633 | } | |
2634 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2635 | ||
6f19efc0 LM |
2636 | /********************************************************************* |
2637 | * BOOST * | |
2638 | *********************************************************************/ | |
cf6fada7 | 2639 | static int cpufreq_boost_set_sw(struct cpufreq_policy *policy, int state) |
6f19efc0 | 2640 | { |
cf6fada7 | 2641 | int ret; |
49f18560 | 2642 | |
cf6fada7 XW |
2643 | if (!policy->freq_table) |
2644 | return -ENXIO; | |
f8bfc116 | 2645 | |
cf6fada7 XW |
2646 | ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table); |
2647 | if (ret) { | |
2648 | pr_err("%s: Policy frequency update failed\n", __func__); | |
2649 | return ret; | |
6f19efc0 LM |
2650 | } |
2651 | ||
cf6fada7 XW |
2652 | ret = freq_qos_update_request(policy->max_freq_req, policy->max); |
2653 | if (ret < 0) | |
2654 | return ret; | |
2655 | ||
552abb88 | 2656 | return 0; |
6f19efc0 LM |
2657 | } |
2658 | ||
2659 | int cpufreq_boost_trigger_state(int state) | |
2660 | { | |
cf6fada7 | 2661 | struct cpufreq_policy *policy; |
6f19efc0 LM |
2662 | unsigned long flags; |
2663 | int ret = 0; | |
2664 | ||
2665 | if (cpufreq_driver->boost_enabled == state) | |
2666 | return 0; | |
2667 | ||
2668 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2669 | cpufreq_driver->boost_enabled = state; | |
2670 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2671 | ||
09681a07 | 2672 | cpus_read_lock(); |
cf6fada7 XW |
2673 | for_each_active_policy(policy) { |
2674 | ret = cpufreq_driver->set_boost(policy, state); | |
2675 | if (ret) | |
2676 | goto err_reset_state; | |
6f19efc0 | 2677 | } |
09681a07 | 2678 | cpus_read_unlock(); |
cf6fada7 XW |
2679 | |
2680 | return 0; | |
2681 | ||
2682 | err_reset_state: | |
09681a07 | 2683 | cpus_read_unlock(); |
cf6fada7 XW |
2684 | |
2685 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2686 | cpufreq_driver->boost_enabled = !state; | |
2687 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2688 | ||
2689 | pr_err("%s: Cannot %s BOOST\n", | |
2690 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2691 | |
2692 | return ret; | |
2693 | } | |
2694 | ||
41669da0 | 2695 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2696 | { |
89f98d7e | 2697 | return cpufreq_driver->set_boost; |
6f19efc0 | 2698 | } |
6f19efc0 | 2699 | |
44139ed4 VK |
2700 | static int create_boost_sysfs_file(void) |
2701 | { | |
2702 | int ret; | |
2703 | ||
c82bd444 | 2704 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2705 | if (ret) |
2706 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2707 | __func__); | |
2708 | ||
2709 | return ret; | |
2710 | } | |
2711 | ||
2712 | static void remove_boost_sysfs_file(void) | |
2713 | { | |
2714 | if (cpufreq_boost_supported()) | |
c82bd444 | 2715 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2716 | } |
2717 | ||
2718 | int cpufreq_enable_boost_support(void) | |
2719 | { | |
2720 | if (!cpufreq_driver) | |
2721 | return -EINVAL; | |
2722 | ||
2723 | if (cpufreq_boost_supported()) | |
2724 | return 0; | |
2725 | ||
7a6c79f2 | 2726 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2727 | |
2728 | /* This will get removed on driver unregister */ | |
2729 | return create_boost_sysfs_file(); | |
2730 | } | |
2731 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2732 | ||
6f19efc0 LM |
2733 | int cpufreq_boost_enabled(void) |
2734 | { | |
2735 | return cpufreq_driver->boost_enabled; | |
2736 | } | |
2737 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2738 | ||
1da177e4 LT |
2739 | /********************************************************************* |
2740 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2741 | *********************************************************************/ | |
27622b06 | 2742 | static enum cpuhp_state hp_online; |
1da177e4 | 2743 | |
c4a3fa26 CY |
2744 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2745 | { | |
2746 | cpufreq_online(cpu); | |
2747 | ||
2748 | return 0; | |
2749 | } | |
2750 | ||
2751 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2752 | { | |
2753 | cpufreq_offline(cpu); | |
2754 | ||
2755 | return 0; | |
2756 | } | |
2757 | ||
3e226946 TG |
2758 | static char cpufreq_driver_name[CPUFREQ_NAME_LEN]; |
2759 | ||
2760 | static int __init cpufreq_driver_setup(char *str) | |
2761 | { | |
2762 | strlcpy(cpufreq_driver_name, str, CPUFREQ_NAME_LEN); | |
2763 | return 1; | |
2764 | } | |
2765 | ||
2766 | /* | |
2767 | * Set this name to only allow one specific cpu freq driver, e.g., | |
2768 | * cpufreq_driver=powernow-k8 | |
2769 | */ | |
2770 | __setup("cpufreq_driver=", cpufreq_driver_setup); | |
2771 | ||
1da177e4 LT |
2772 | /** |
2773 | * cpufreq_register_driver - register a CPU Frequency driver | |
2774 | * @driver_data: A struct cpufreq_driver containing the values# | |
2775 | * submitted by the CPU Frequency driver. | |
2776 | * | |
bb176f7d | 2777 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2778 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2779 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2780 | * |
2781 | */ | |
221dee28 | 2782 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2783 | { |
2784 | unsigned long flags; | |
2785 | int ret; | |
2786 | ||
a7b422cd KRW |
2787 | if (cpufreq_disabled()) |
2788 | return -ENODEV; | |
2789 | ||
46770be0 VK |
2790 | /* |
2791 | * The cpufreq core depends heavily on the availability of device | |
2792 | * structure, make sure they are available before proceeding further. | |
2793 | */ | |
2794 | if (!get_cpu_device(0)) | |
2795 | return -EPROBE_DEFER; | |
2796 | ||
1da177e4 | 2797 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2798 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2799 | driver_data->target) || |
2800 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2801 | driver_data->target)) || |
a9a22b57 | 2802 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2803 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2804 | return -EINVAL; |
2805 | ||
3e226946 TG |
2806 | pr_debug("trying to register driver %s, cpufreq_driver=%s\n", |
2807 | driver_data->name, cpufreq_driver_name); | |
2808 | ||
2809 | if (cpufreq_driver_name[0]) | |
2810 | if (!driver_data->name || | |
2811 | strcmp(cpufreq_driver_name, driver_data->name)) | |
2812 | return -EINVAL; | |
1da177e4 | 2813 | |
fdd320da | 2814 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2815 | cpus_read_lock(); |
fdd320da | 2816 | |
0d1857a1 | 2817 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2818 | if (cpufreq_driver) { |
0d1857a1 | 2819 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2820 | ret = -EEXIST; |
2821 | goto out; | |
1da177e4 | 2822 | } |
1c3d85dd | 2823 | cpufreq_driver = driver_data; |
0d1857a1 | 2824 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2825 | |
874f6353 IV |
2826 | /* |
2827 | * Mark support for the scheduler's frequency invariance engine for | |
2828 | * drivers that implement target(), target_index() or fast_switch(). | |
2829 | */ | |
2830 | if (!cpufreq_driver->setpolicy) { | |
2831 | static_branch_enable_cpuslocked(&cpufreq_freq_invariance); | |
2832 | pr_debug("supports frequency invariance"); | |
2833 | } | |
2834 | ||
bc68b7df VK |
2835 | if (driver_data->setpolicy) |
2836 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2837 | ||
7a6c79f2 RW |
2838 | if (cpufreq_boost_supported()) { |
2839 | ret = create_boost_sysfs_file(); | |
2840 | if (ret) | |
2841 | goto err_null_driver; | |
2842 | } | |
6f19efc0 | 2843 | |
8a25a2fd | 2844 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2845 | if (ret) |
6f19efc0 | 2846 | goto err_boost_unreg; |
1da177e4 | 2847 | |
5ae4a4b4 | 2848 | if (unlikely(list_empty(&cpufreq_policy_list))) { |
1da177e4 | 2849 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2850 | ret = -ENODEV; |
ce1bcfe9 VK |
2851 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2852 | driver_data->name); | |
2853 | goto err_if_unreg; | |
1da177e4 LT |
2854 | } |
2855 | ||
a92551e4 SAS |
2856 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2857 | "cpufreq:online", | |
2858 | cpuhp_cpufreq_online, | |
2859 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2860 | if (ret < 0) |
2861 | goto err_if_unreg; | |
2862 | hp_online = ret; | |
5372e054 | 2863 | ret = 0; |
27622b06 | 2864 | |
2d06d8c4 | 2865 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2866 | goto out; |
fdd320da | 2867 | |
8a25a2fd KS |
2868 | err_if_unreg: |
2869 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2870 | err_boost_unreg: |
44139ed4 | 2871 | remove_boost_sysfs_file(); |
8f5bc2ab | 2872 | err_null_driver: |
0d1857a1 | 2873 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2874 | cpufreq_driver = NULL; |
0d1857a1 | 2875 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2876 | out: |
a92551e4 | 2877 | cpus_read_unlock(); |
3834abb4 | 2878 | return ret; |
1da177e4 LT |
2879 | } |
2880 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2881 | ||
a9909c21 | 2882 | /* |
1da177e4 LT |
2883 | * cpufreq_unregister_driver - unregister the current CPUFreq driver |
2884 | * | |
bb176f7d | 2885 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2886 | * the right to do so, i.e. if you have succeeded in initialising before! |
2887 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2888 | * currently not initialised. | |
2889 | */ | |
221dee28 | 2890 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2891 | { |
2892 | unsigned long flags; | |
2893 | ||
1c3d85dd | 2894 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2895 | return -EINVAL; |
1da177e4 | 2896 | |
2d06d8c4 | 2897 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2898 | |
454d3a25 | 2899 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2900 | cpus_read_lock(); |
8a25a2fd | 2901 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2902 | remove_boost_sysfs_file(); |
874f6353 | 2903 | static_branch_disable_cpuslocked(&cpufreq_freq_invariance); |
a92551e4 | 2904 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2905 | |
0d1857a1 | 2906 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2907 | |
1c3d85dd | 2908 | cpufreq_driver = NULL; |
6eed9404 | 2909 | |
0d1857a1 | 2910 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2911 | cpus_read_unlock(); |
1da177e4 LT |
2912 | |
2913 | return 0; | |
2914 | } | |
2915 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2916 | |
2917 | static int __init cpufreq_core_init(void) | |
2918 | { | |
8412b456 QP |
2919 | struct cpufreq_governor *gov = cpufreq_default_governor(); |
2920 | ||
a7b422cd KRW |
2921 | if (cpufreq_disabled()) |
2922 | return -ENODEV; | |
2923 | ||
8eec1020 | 2924 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2925 | BUG_ON(!cpufreq_global_kobject); |
2926 | ||
8412b456 QP |
2927 | if (!strlen(default_governor)) |
2928 | strncpy(default_governor, gov->name, CPUFREQ_NAME_LEN); | |
2929 | ||
5a01f2e8 VP |
2930 | return 0; |
2931 | } | |
d82f2692 | 2932 | module_param(off, int, 0444); |
8412b456 | 2933 | module_param_string(default_governor, default_governor, CPUFREQ_NAME_LEN, 0444); |
5a01f2e8 | 2934 | core_initcall(cpufreq_core_init); |