Commit | Line | Data |
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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> |
f55ae08c | 31 | #include <linux/units.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
b4f0676f | 34 | static LIST_HEAD(cpufreq_policy_list); |
f963735a | 35 | |
f963735a | 36 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
37 | #define for_each_suitable_policy(__policy, __active) \ |
38 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
39 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
40 | |
41 | #define for_each_active_policy(__policy) \ | |
42 | for_each_suitable_policy(__policy, true) | |
43 | #define for_each_inactive_policy(__policy) \ | |
44 | for_each_suitable_policy(__policy, false) | |
45 | ||
f7b27061 VK |
46 | /* Iterate over governors */ |
47 | static LIST_HEAD(cpufreq_governor_list); | |
48 | #define for_each_governor(__governor) \ | |
49 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
50 | ||
8412b456 QP |
51 | static char default_governor[CPUFREQ_NAME_LEN]; |
52 | ||
a9909c21 | 53 | /* |
cd878479 | 54 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
55 | * level driver of CPUFreq support, and its spinlock. This lock |
56 | * also protects the cpufreq_cpu_data array. | |
57 | */ | |
1c3d85dd | 58 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 59 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 60 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 61 | |
874f6353 IV |
62 | static DEFINE_STATIC_KEY_FALSE(cpufreq_freq_invariance); |
63 | bool cpufreq_supports_freq_invariance(void) | |
64 | { | |
65 | return static_branch_likely(&cpufreq_freq_invariance); | |
66 | } | |
67 | ||
2f0aea93 VK |
68 | /* Flag to suspend/resume CPUFreq governors */ |
69 | static bool cpufreq_suspended; | |
1da177e4 | 70 | |
9c0ebcf7 VK |
71 | static inline bool has_target(void) |
72 | { | |
73 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
74 | } | |
75 | ||
a038895e VK |
76 | bool has_target_index(void) |
77 | { | |
78 | return !!cpufreq_driver->target_index; | |
79 | } | |
80 | ||
1da177e4 | 81 | /* internal prototypes */ |
d92d50a4 | 82 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
83 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
84 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
a92604b4 | 85 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); |
1e4f63ae RW |
86 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
87 | struct cpufreq_governor *new_gov, | |
88 | unsigned int new_pol); | |
45482c70 | 89 | |
a9909c21 | 90 | /* |
32ee8c3e DJ |
91 | * Two notifier lists: the "policy" list is involved in the |
92 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
93 | * "transition" list for kernel code that needs to handle |
94 | * changes to devices when the CPU clock speed changes. | |
95 | * The mutex locks both lists. | |
96 | */ | |
e041c683 | 97 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 98 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 99 | |
a7b422cd | 100 | static int off __read_mostly; |
da584455 | 101 | static int cpufreq_disabled(void) |
a7b422cd KRW |
102 | { |
103 | return off; | |
104 | } | |
105 | void disable_cpufreq(void) | |
106 | { | |
107 | off = 1; | |
108 | } | |
29464f28 | 109 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 110 | |
4d5dcc42 VK |
111 | bool have_governor_per_policy(void) |
112 | { | |
0b981e70 | 113 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 114 | } |
3f869d6d | 115 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 116 | |
183edb20 YL |
117 | static struct kobject *cpufreq_global_kobject; |
118 | ||
944e9a03 VK |
119 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
120 | { | |
121 | if (have_governor_per_policy()) | |
122 | return &policy->kobj; | |
123 | else | |
124 | return cpufreq_global_kobject; | |
125 | } | |
126 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
127 | ||
72a4ce34 VK |
128 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
129 | { | |
5720821b | 130 | struct kernel_cpustat kcpustat; |
72a4ce34 | 131 | u64 cur_wall_time; |
5720821b | 132 | u64 idle_time; |
72a4ce34 VK |
133 | u64 busy_time; |
134 | ||
7fb1327e | 135 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 | 136 | |
5720821b FW |
137 | kcpustat_cpu_fetch(&kcpustat, cpu); |
138 | ||
139 | busy_time = kcpustat.cpustat[CPUTIME_USER]; | |
140 | busy_time += kcpustat.cpustat[CPUTIME_SYSTEM]; | |
141 | busy_time += kcpustat.cpustat[CPUTIME_IRQ]; | |
142 | busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ]; | |
143 | busy_time += kcpustat.cpustat[CPUTIME_STEAL]; | |
144 | busy_time += kcpustat.cpustat[CPUTIME_NICE]; | |
72a4ce34 VK |
145 | |
146 | idle_time = cur_wall_time - busy_time; | |
147 | if (wall) | |
7fb1327e | 148 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 149 | |
7fb1327e | 150 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
151 | } |
152 | ||
153 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
154 | { | |
155 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
156 | ||
157 | if (idle_time == -1ULL) | |
158 | return get_cpu_idle_time_jiffy(cpu, wall); | |
159 | else if (!io_busy) | |
160 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
161 | ||
162 | return idle_time; | |
163 | } | |
164 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
165 | ||
70e9e778 VK |
166 | /* |
167 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
168 | * drivers of SMP systems. It will do following: | |
169 | * - validate & show freq table passed | |
170 | * - set policies transition latency | |
171 | * - policy->cpus with all possible CPUs | |
172 | */ | |
c4dcc8a1 | 173 | void cpufreq_generic_init(struct cpufreq_policy *policy, |
70e9e778 VK |
174 | struct cpufreq_frequency_table *table, |
175 | unsigned int transition_latency) | |
176 | { | |
92c99d15 | 177 | policy->freq_table = table; |
70e9e778 VK |
178 | policy->cpuinfo.transition_latency = transition_latency; |
179 | ||
180 | /* | |
58405af6 | 181 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
182 | * share the clock and voltage and clock. |
183 | */ | |
184 | cpumask_setall(policy->cpus); | |
70e9e778 VK |
185 | } |
186 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
187 | ||
1f0bd44e | 188 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
189 | { |
190 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
191 | ||
988bed09 VK |
192 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
193 | } | |
1f0bd44e | 194 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
195 | |
196 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
197 | { | |
198 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
199 | ||
652ed95d | 200 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
201 | pr_err("%s: No %s associated to cpu: %d\n", |
202 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
203 | return 0; |
204 | } | |
205 | ||
206 | return clk_get_rate(policy->clk) / 1000; | |
207 | } | |
208 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
209 | ||
50e9c852 | 210 | /** |
5d094fea RW |
211 | * cpufreq_cpu_get - Return policy for a CPU and mark it as busy. |
212 | * @cpu: CPU to find the policy for. | |
50e9c852 | 213 | * |
5d094fea RW |
214 | * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment |
215 | * the kobject reference counter of that policy. Return a valid policy on | |
216 | * success or NULL on failure. | |
50e9c852 | 217 | * |
5d094fea RW |
218 | * The policy returned by this function has to be released with the help of |
219 | * cpufreq_cpu_put() to balance its kobject reference counter properly. | |
50e9c852 | 220 | */ |
6eed9404 | 221 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 222 | { |
6eed9404 | 223 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
224 | unsigned long flags; |
225 | ||
1b947c90 | 226 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
227 | return NULL; |
228 | ||
1da177e4 | 229 | /* get the cpufreq driver */ |
1c3d85dd | 230 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 231 | |
6eed9404 VK |
232 | if (cpufreq_driver) { |
233 | /* get the CPU */ | |
988bed09 | 234 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
235 | if (policy) |
236 | kobject_get(&policy->kobj); | |
237 | } | |
1da177e4 | 238 | |
6eed9404 | 239 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 240 | |
3a3e9e06 | 241 | return policy; |
a9144436 | 242 | } |
1da177e4 LT |
243 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
244 | ||
50e9c852 | 245 | /** |
5d094fea RW |
246 | * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy. |
247 | * @policy: cpufreq policy returned by cpufreq_cpu_get(). | |
50e9c852 | 248 | */ |
3a3e9e06 | 249 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 250 | { |
6eed9404 | 251 | kobject_put(&policy->kobj); |
1da177e4 LT |
252 | } |
253 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
254 | ||
540a3758 RW |
255 | /** |
256 | * cpufreq_cpu_release - Unlock a policy and decrement its usage counter. | |
257 | * @policy: cpufreq policy returned by cpufreq_cpu_acquire(). | |
258 | */ | |
9083e498 | 259 | void cpufreq_cpu_release(struct cpufreq_policy *policy) |
540a3758 RW |
260 | { |
261 | if (WARN_ON(!policy)) | |
262 | return; | |
263 | ||
264 | lockdep_assert_held(&policy->rwsem); | |
265 | ||
266 | up_write(&policy->rwsem); | |
267 | ||
268 | cpufreq_cpu_put(policy); | |
269 | } | |
270 | ||
271 | /** | |
272 | * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it. | |
273 | * @cpu: CPU to find the policy for. | |
274 | * | |
275 | * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and | |
276 | * if the policy returned by it is not NULL, acquire its rwsem for writing. | |
277 | * Return the policy if it is active or release it and return NULL otherwise. | |
278 | * | |
279 | * The policy returned by this function has to be released with the help of | |
280 | * cpufreq_cpu_release() in order to release its rwsem and balance its usage | |
281 | * counter properly. | |
282 | */ | |
9083e498 | 283 | struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) |
540a3758 RW |
284 | { |
285 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
286 | ||
287 | if (!policy) | |
288 | return NULL; | |
289 | ||
290 | down_write(&policy->rwsem); | |
291 | ||
292 | if (policy_is_inactive(policy)) { | |
293 | cpufreq_cpu_release(policy); | |
294 | return NULL; | |
295 | } | |
296 | ||
297 | return policy; | |
298 | } | |
299 | ||
1da177e4 LT |
300 | /********************************************************************* |
301 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
302 | *********************************************************************/ | |
303 | ||
ec06e586 RW |
304 | /** |
305 | * adjust_jiffies - Adjust the system "loops_per_jiffy". | |
306 | * @val: CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
307 | * @ci: Frequency change information. | |
1da177e4 LT |
308 | * |
309 | * This function alters the system "loops_per_jiffy" for the clock | |
310 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 311 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
312 | * per-CPU loops_per_jiffy value wherever possible. |
313 | */ | |
858119e1 | 314 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 315 | { |
39c132ee VK |
316 | #ifndef CONFIG_SMP |
317 | static unsigned long l_p_j_ref; | |
318 | static unsigned int l_p_j_ref_freq; | |
319 | ||
1da177e4 LT |
320 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
321 | return; | |
322 | ||
323 | if (!l_p_j_ref_freq) { | |
324 | l_p_j_ref = loops_per_jiffy; | |
325 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
326 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
327 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 328 | } |
0b443ead | 329 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
330 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
331 | ci->new); | |
e837f9b5 JP |
332 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
333 | loops_per_jiffy, ci->new); | |
1da177e4 | 334 | } |
1da177e4 | 335 | #endif |
39c132ee | 336 | } |
1da177e4 | 337 | |
20b5324d | 338 | /** |
ec06e586 | 339 | * cpufreq_notify_transition - Notify frequency transition and adjust jiffies. |
20b5324d VK |
340 | * @policy: cpufreq policy to enable fast frequency switching for. |
341 | * @freqs: contain details of the frequency update. | |
342 | * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
343 | * | |
ec06e586 RW |
344 | * This function calls the transition notifiers and adjust_jiffies(). |
345 | * | |
346 | * It is called twice on all CPU frequency changes that have external effects. | |
20b5324d VK |
347 | */ |
348 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
349 | struct cpufreq_freqs *freqs, | |
350 | unsigned int state) | |
1da177e4 | 351 | { |
df24014a VK |
352 | int cpu; |
353 | ||
1da177e4 LT |
354 | BUG_ON(irqs_disabled()); |
355 | ||
d5aaffa9 DB |
356 | if (cpufreq_disabled()) |
357 | return; | |
358 | ||
df24014a | 359 | freqs->policy = policy; |
1c3d85dd | 360 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 361 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 362 | state, freqs->new); |
1da177e4 | 363 | |
1da177e4 LT |
364 | switch (state) { |
365 | case CPUFREQ_PRECHANGE: | |
20b5324d VK |
366 | /* |
367 | * Detect if the driver reported a value as "old frequency" | |
e4472cb3 DJ |
368 | * which is not equal to what the cpufreq core thinks is |
369 | * "old frequency". | |
1da177e4 | 370 | */ |
98015228 VK |
371 | if (policy->cur && policy->cur != freqs->old) { |
372 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", | |
373 | freqs->old, policy->cur); | |
374 | freqs->old = policy->cur; | |
1da177e4 | 375 | } |
20b5324d | 376 | |
df24014a VK |
377 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
378 | CPUFREQ_PRECHANGE, freqs); | |
20b5324d | 379 | |
1da177e4 LT |
380 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
381 | break; | |
e4472cb3 | 382 | |
1da177e4 LT |
383 | case CPUFREQ_POSTCHANGE: |
384 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
20b5324d VK |
385 | pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, |
386 | cpumask_pr_args(policy->cpus)); | |
387 | ||
df24014a VK |
388 | for_each_cpu(cpu, policy->cpus) |
389 | trace_cpu_frequency(freqs->new, cpu); | |
390 | ||
391 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, | |
392 | CPUFREQ_POSTCHANGE, freqs); | |
20b5324d | 393 | |
1aefc75b | 394 | cpufreq_stats_record_transition(policy, freqs->new); |
20b5324d | 395 | policy->cur = freqs->new; |
1da177e4 | 396 | } |
1da177e4 | 397 | } |
bb176f7d | 398 | |
f7ba3b41 | 399 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 400 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
401 | struct cpufreq_freqs *freqs, int transition_failed) |
402 | { | |
403 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
404 | if (!transition_failed) | |
405 | return; | |
406 | ||
407 | swap(freqs->old, freqs->new); | |
408 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
409 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
410 | } | |
f7ba3b41 | 411 | |
12478cf0 SB |
412 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
413 | struct cpufreq_freqs *freqs) | |
414 | { | |
ca654dc3 SB |
415 | |
416 | /* | |
417 | * Catch double invocations of _begin() which lead to self-deadlock. | |
418 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
419 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
420 | * double invocations are very low. Moreover, there are scenarios | |
421 | * where these checks can emit false-positive warnings in these | |
422 | * drivers; so we avoid that by skipping them altogether. | |
423 | */ | |
424 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
425 | && current == policy->transition_task); | |
426 | ||
12478cf0 SB |
427 | wait: |
428 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
429 | ||
430 | spin_lock(&policy->transition_lock); | |
431 | ||
432 | if (unlikely(policy->transition_ongoing)) { | |
433 | spin_unlock(&policy->transition_lock); | |
434 | goto wait; | |
435 | } | |
436 | ||
437 | policy->transition_ongoing = true; | |
ca654dc3 | 438 | policy->transition_task = current; |
12478cf0 SB |
439 | |
440 | spin_unlock(&policy->transition_lock); | |
441 | ||
442 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
443 | } | |
444 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
445 | ||
446 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
447 | struct cpufreq_freqs *freqs, int transition_failed) | |
448 | { | |
0e7ea2f3 | 449 | if (WARN_ON(!policy->transition_ongoing)) |
12478cf0 SB |
450 | return; |
451 | ||
452 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
453 | ||
1a0419b0 IV |
454 | arch_set_freq_scale(policy->related_cpus, |
455 | policy->cur, | |
456 | policy->cpuinfo.max_freq); | |
457 | ||
12478cf0 | 458 | policy->transition_ongoing = false; |
ca654dc3 | 459 | policy->transition_task = NULL; |
12478cf0 SB |
460 | |
461 | wake_up(&policy->transition_wait); | |
462 | } | |
463 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
464 | ||
b7898fda RW |
465 | /* |
466 | * Fast frequency switching status count. Positive means "enabled", negative | |
467 | * means "disabled" and 0 means "not decided yet". | |
468 | */ | |
469 | static int cpufreq_fast_switch_count; | |
470 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
471 | ||
472 | static void cpufreq_list_transition_notifiers(void) | |
473 | { | |
474 | struct notifier_block *nb; | |
475 | ||
476 | pr_info("Registered transition notifiers:\n"); | |
477 | ||
478 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
479 | ||
480 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
d75f773c | 481 | pr_info("%pS\n", nb->notifier_call); |
b7898fda RW |
482 | |
483 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
484 | } | |
485 | ||
486 | /** | |
487 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
488 | * @policy: cpufreq policy to enable fast frequency switching for. | |
489 | * | |
490 | * Try to enable fast frequency switching for @policy. | |
491 | * | |
492 | * The attempt will fail if there is at least one transition notifier registered | |
493 | * at this point, as fast frequency switching is quite fundamentally at odds | |
494 | * with transition notifiers. Thus if successful, it will make registration of | |
495 | * transition notifiers fail going forward. | |
496 | */ | |
497 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
498 | { | |
499 | lockdep_assert_held(&policy->rwsem); | |
500 | ||
501 | if (!policy->fast_switch_possible) | |
502 | return; | |
503 | ||
504 | mutex_lock(&cpufreq_fast_switch_lock); | |
505 | if (cpufreq_fast_switch_count >= 0) { | |
506 | cpufreq_fast_switch_count++; | |
507 | policy->fast_switch_enabled = true; | |
508 | } else { | |
509 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
510 | policy->cpu); | |
511 | cpufreq_list_transition_notifiers(); | |
512 | } | |
513 | mutex_unlock(&cpufreq_fast_switch_lock); | |
514 | } | |
515 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
516 | ||
6c9d9c81 RW |
517 | /** |
518 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
519 | * @policy: cpufreq policy to disable fast frequency switching for. | |
520 | */ | |
521 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
522 | { |
523 | mutex_lock(&cpufreq_fast_switch_lock); | |
524 | if (policy->fast_switch_enabled) { | |
525 | policy->fast_switch_enabled = false; | |
526 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
527 | cpufreq_fast_switch_count--; | |
528 | } | |
529 | mutex_unlock(&cpufreq_fast_switch_lock); | |
530 | } | |
6c9d9c81 | 531 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 532 | |
f9ccdec2 VK |
533 | static unsigned int __resolve_freq(struct cpufreq_policy *policy, |
534 | unsigned int target_freq, unsigned int relation) | |
e3c06236 | 535 | { |
b3beca76 | 536 | unsigned int idx; |
abe8bd02 | 537 | |
b3beca76 | 538 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
abe8bd02 | 539 | |
6ca7076f | 540 | if (!policy->freq_table) |
b3beca76 | 541 | return target_freq; |
abe8bd02 | 542 | |
b3beca76 VK |
543 | idx = cpufreq_frequency_table_target(policy, target_freq, relation); |
544 | policy->cached_resolved_idx = idx; | |
545 | policy->cached_target_freq = target_freq; | |
546 | return policy->freq_table[idx].frequency; | |
e3c06236 | 547 | } |
f9ccdec2 VK |
548 | |
549 | /** | |
550 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
551 | * one. | |
552 | * @policy: associated policy to interrogate | |
553 | * @target_freq: target frequency to resolve. | |
554 | * | |
555 | * The target to driver frequency mapping is cached in the policy. | |
556 | * | |
557 | * Return: Lowest driver-supported frequency greater than or equal to the | |
558 | * given target_freq, subject to policy (min/max) and driver limitations. | |
559 | */ | |
560 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
561 | unsigned int target_freq) | |
562 | { | |
b894d20e | 563 | return __resolve_freq(policy, target_freq, CPUFREQ_RELATION_LE); |
f9ccdec2 | 564 | } |
ae2c1ca6 | 565 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 566 | |
aa7519af VK |
567 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
568 | { | |
569 | unsigned int latency; | |
570 | ||
571 | if (policy->transition_delay_us) | |
572 | return policy->transition_delay_us; | |
573 | ||
574 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
575 | if (latency) { |
576 | /* | |
577 | * For platforms that can change the frequency very fast (< 10 | |
578 | * us), the above formula gives a decent transition delay. But | |
579 | * for platforms where transition_latency is in milliseconds, it | |
580 | * ends up giving unrealistic values. | |
581 | * | |
582 | * Cap the default transition delay to 10 ms, which seems to be | |
583 | * a reasonable amount of time after which we should reevaluate | |
584 | * the frequency. | |
585 | */ | |
586 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
587 | } | |
aa7519af VK |
588 | |
589 | return LATENCY_MULTIPLIER; | |
590 | } | |
591 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
592 | ||
1da177e4 LT |
593 | /********************************************************************* |
594 | * SYSFS INTERFACE * | |
595 | *********************************************************************/ | |
8a5c74a1 | 596 | static ssize_t show_boost(struct kobject *kobj, |
625c85a6 | 597 | struct kobj_attribute *attr, char *buf) |
6f19efc0 LM |
598 | { |
599 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
600 | } | |
601 | ||
625c85a6 VK |
602 | static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, |
603 | const char *buf, size_t count) | |
6f19efc0 LM |
604 | { |
605 | int ret, enable; | |
606 | ||
607 | ret = sscanf(buf, "%d", &enable); | |
608 | if (ret != 1 || enable < 0 || enable > 1) | |
609 | return -EINVAL; | |
610 | ||
611 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
612 | pr_err("%s: Cannot %s BOOST!\n", |
613 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
614 | return -EINVAL; |
615 | } | |
616 | ||
e837f9b5 JP |
617 | pr_debug("%s: cpufreq BOOST %s\n", |
618 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
619 | |
620 | return count; | |
621 | } | |
622 | define_one_global_rw(boost); | |
1da177e4 | 623 | |
42f91fa1 | 624 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
625 | { |
626 | struct cpufreq_governor *t; | |
627 | ||
f7b27061 | 628 | for_each_governor(t) |
7c4f4539 | 629 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
630 | return t; |
631 | ||
632 | return NULL; | |
633 | } | |
634 | ||
8cc46ae5 VK |
635 | static struct cpufreq_governor *get_governor(const char *str_governor) |
636 | { | |
637 | struct cpufreq_governor *t; | |
638 | ||
639 | mutex_lock(&cpufreq_governor_mutex); | |
640 | t = find_governor(str_governor); | |
641 | if (!t) | |
642 | goto unlock; | |
643 | ||
644 | if (!try_module_get(t->owner)) | |
645 | t = NULL; | |
646 | ||
647 | unlock: | |
648 | mutex_unlock(&cpufreq_governor_mutex); | |
649 | ||
650 | return t; | |
651 | } | |
652 | ||
1e4f63ae | 653 | static unsigned int cpufreq_parse_policy(char *str_governor) |
ab05d97a | 654 | { |
1e4f63ae RW |
655 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) |
656 | return CPUFREQ_POLICY_PERFORMANCE; | |
657 | ||
658 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) | |
659 | return CPUFREQ_POLICY_POWERSAVE; | |
660 | ||
661 | return CPUFREQ_POLICY_UNKNOWN; | |
ab05d97a YH |
662 | } |
663 | ||
1da177e4 | 664 | /** |
5ddc6d4e | 665 | * cpufreq_parse_governor - parse a governor string only for has_target() |
1e4f63ae | 666 | * @str_governor: Governor name. |
1da177e4 | 667 | */ |
1e4f63ae | 668 | static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor) |
1da177e4 | 669 | { |
ab05d97a | 670 | struct cpufreq_governor *t; |
045149e6 | 671 | |
8cc46ae5 VK |
672 | t = get_governor(str_governor); |
673 | if (t) | |
674 | return t; | |
ea714970 | 675 | |
8cc46ae5 VK |
676 | if (request_module("cpufreq_%s", str_governor)) |
677 | return NULL; | |
045149e6 | 678 | |
8cc46ae5 | 679 | return get_governor(str_governor); |
1da177e4 | 680 | } |
1da177e4 | 681 | |
a9909c21 | 682 | /* |
e08f5f5b GS |
683 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
684 | * print out cpufreq information | |
1da177e4 LT |
685 | * |
686 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
687 | * "unsigned int". | |
688 | */ | |
689 | ||
32ee8c3e DJ |
690 | #define show_one(file_name, object) \ |
691 | static ssize_t show_##file_name \ | |
905d77cd | 692 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 693 | { \ |
29464f28 | 694 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
695 | } |
696 | ||
697 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
698 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 699 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
700 | show_one(scaling_min_freq, min); |
701 | show_one(scaling_max_freq, max); | |
c034b02e | 702 | |
f8475cef LB |
703 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
704 | { | |
705 | return 0; | |
706 | } | |
707 | ||
09347b29 | 708 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
709 | { |
710 | ssize_t ret; | |
f8475cef | 711 | unsigned int freq; |
c034b02e | 712 | |
f8475cef LB |
713 | freq = arch_freq_get_on_cpu(policy->cpu); |
714 | if (freq) | |
715 | ret = sprintf(buf, "%u\n", freq); | |
681fe684 | 716 | else if (cpufreq_driver->setpolicy && cpufreq_driver->get) |
c034b02e DB |
717 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
718 | else | |
719 | ret = sprintf(buf, "%u\n", policy->cur); | |
720 | return ret; | |
721 | } | |
1da177e4 | 722 | |
a9909c21 | 723 | /* |
1da177e4 LT |
724 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access |
725 | */ | |
726 | #define store_one(file_name, object) \ | |
727 | static ssize_t store_##file_name \ | |
905d77cd | 728 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 729 | { \ |
18c49926 VK |
730 | unsigned long val; \ |
731 | int ret; \ | |
1da177e4 | 732 | \ |
877d5cd2 | 733 | ret = kstrtoul(buf, 0, &val); \ |
734 | if (ret) \ | |
735 | return ret; \ | |
1da177e4 | 736 | \ |
3000ce3c | 737 | ret = freq_qos_update_request(policy->object##_freq_req, val);\ |
18c49926 | 738 | return ret >= 0 ? count : ret; \ |
1da177e4 LT |
739 | } |
740 | ||
29464f28 DJ |
741 | store_one(scaling_min_freq, min); |
742 | store_one(scaling_max_freq, max); | |
1da177e4 | 743 | |
a9909c21 | 744 | /* |
1da177e4 LT |
745 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware |
746 | */ | |
905d77cd DJ |
747 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
748 | char *buf) | |
1da177e4 | 749 | { |
d92d50a4 | 750 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
751 | |
752 | if (cur_freq) | |
753 | return sprintf(buf, "%u\n", cur_freq); | |
754 | ||
755 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
756 | } |
757 | ||
a9909c21 | 758 | /* |
1da177e4 LT |
759 | * show_scaling_governor - show the current policy for the specified CPU |
760 | */ | |
905d77cd | 761 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 762 | { |
29464f28 | 763 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
764 | return sprintf(buf, "powersave\n"); |
765 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
766 | return sprintf(buf, "performance\n"); | |
767 | else if (policy->governor) | |
4b972f0b | 768 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 769 | policy->governor->name); |
1da177e4 LT |
770 | return -EINVAL; |
771 | } | |
772 | ||
a9909c21 | 773 | /* |
1da177e4 LT |
774 | * store_scaling_governor - store policy for the specified CPU |
775 | */ | |
905d77cd DJ |
776 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
777 | const char *buf, size_t count) | |
1da177e4 | 778 | { |
1e4f63ae | 779 | char str_governor[16]; |
5136fa56 | 780 | int ret; |
1da177e4 | 781 | |
29464f28 | 782 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
783 | if (ret != 1) |
784 | return -EINVAL; | |
785 | ||
ab05d97a | 786 | if (cpufreq_driver->setpolicy) { |
1e4f63ae RW |
787 | unsigned int new_pol; |
788 | ||
789 | new_pol = cpufreq_parse_policy(str_governor); | |
790 | if (!new_pol) | |
ab05d97a | 791 | return -EINVAL; |
1e4f63ae RW |
792 | |
793 | ret = cpufreq_set_policy(policy, NULL, new_pol); | |
ab05d97a | 794 | } else { |
1e4f63ae RW |
795 | struct cpufreq_governor *new_gov; |
796 | ||
797 | new_gov = cpufreq_parse_governor(str_governor); | |
798 | if (!new_gov) | |
ab05d97a | 799 | return -EINVAL; |
1da177e4 | 800 | |
1e4f63ae RW |
801 | ret = cpufreq_set_policy(policy, new_gov, |
802 | CPUFREQ_POLICY_UNKNOWN); | |
a8b149d3 | 803 | |
1e4f63ae RW |
804 | module_put(new_gov->owner); |
805 | } | |
a8b149d3 | 806 | |
88dc4384 | 807 | return ret ? ret : count; |
1da177e4 LT |
808 | } |
809 | ||
a9909c21 | 810 | /* |
1da177e4 LT |
811 | * show_scaling_driver - show the cpufreq driver currently loaded |
812 | */ | |
905d77cd | 813 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 814 | { |
1c3d85dd | 815 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
816 | } |
817 | ||
a9909c21 | 818 | /* |
1da177e4 LT |
819 | * show_scaling_available_governors - show the available CPUfreq governors |
820 | */ | |
905d77cd DJ |
821 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
822 | char *buf) | |
1da177e4 LT |
823 | { |
824 | ssize_t i = 0; | |
825 | struct cpufreq_governor *t; | |
826 | ||
9c0ebcf7 | 827 | if (!has_target()) { |
1da177e4 LT |
828 | i += sprintf(buf, "performance powersave"); |
829 | goto out; | |
830 | } | |
831 | ||
8cc46ae5 | 832 | mutex_lock(&cpufreq_governor_mutex); |
f7b27061 | 833 | for_each_governor(t) { |
29464f28 DJ |
834 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
835 | - (CPUFREQ_NAME_LEN + 2))) | |
8cc46ae5 | 836 | break; |
4b972f0b | 837 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 838 | } |
8cc46ae5 | 839 | mutex_unlock(&cpufreq_governor_mutex); |
7d5e350f | 840 | out: |
1da177e4 LT |
841 | i += sprintf(&buf[i], "\n"); |
842 | return i; | |
843 | } | |
e8628dd0 | 844 | |
f4fd3797 | 845 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
846 | { |
847 | ssize_t i = 0; | |
848 | unsigned int cpu; | |
849 | ||
835481d9 | 850 | for_each_cpu(cpu, mask) { |
336e5128 | 851 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u ", cpu); |
1da177e4 | 852 | if (i >= (PAGE_SIZE - 5)) |
29464f28 | 853 | break; |
1da177e4 | 854 | } |
336e5128 VK |
855 | |
856 | /* Remove the extra space at the end */ | |
857 | i--; | |
858 | ||
1da177e4 LT |
859 | i += sprintf(&buf[i], "\n"); |
860 | return i; | |
861 | } | |
f4fd3797 | 862 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 863 | |
a9909c21 | 864 | /* |
e8628dd0 DW |
865 | * show_related_cpus - show the CPUs affected by each transition even if |
866 | * hw coordination is in use | |
867 | */ | |
868 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
869 | { | |
f4fd3797 | 870 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
871 | } |
872 | ||
a9909c21 | 873 | /* |
e8628dd0 DW |
874 | * show_affected_cpus - show the CPUs affected by each transition |
875 | */ | |
876 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
877 | { | |
f4fd3797 | 878 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
879 | } |
880 | ||
9e76988e | 881 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 882 | const char *buf, size_t count) |
9e76988e VP |
883 | { |
884 | unsigned int freq = 0; | |
885 | unsigned int ret; | |
886 | ||
879000f9 | 887 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
888 | return -EINVAL; |
889 | ||
890 | ret = sscanf(buf, "%u", &freq); | |
891 | if (ret != 1) | |
892 | return -EINVAL; | |
893 | ||
894 | policy->governor->store_setspeed(policy, freq); | |
895 | ||
896 | return count; | |
897 | } | |
898 | ||
899 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
900 | { | |
879000f9 | 901 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
902 | return sprintf(buf, "<unsupported>\n"); |
903 | ||
904 | return policy->governor->show_setspeed(policy, buf); | |
905 | } | |
1da177e4 | 906 | |
a9909c21 | 907 | /* |
8bf1ac72 | 908 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
909 | */ |
910 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
911 | { | |
912 | unsigned int limit; | |
913 | int ret; | |
b23aa311 YH |
914 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
915 | if (!ret) | |
916 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
917 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
918 | } | |
919 | ||
6dad2a29 BP |
920 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
921 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
922 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
923 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
924 | cpufreq_freq_attr_ro(scaling_available_governors); | |
925 | cpufreq_freq_attr_ro(scaling_driver); | |
926 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
927 | cpufreq_freq_attr_ro(bios_limit); | |
928 | cpufreq_freq_attr_ro(related_cpus); | |
929 | cpufreq_freq_attr_ro(affected_cpus); | |
930 | cpufreq_freq_attr_rw(scaling_min_freq); | |
931 | cpufreq_freq_attr_rw(scaling_max_freq); | |
932 | cpufreq_freq_attr_rw(scaling_governor); | |
933 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 934 | |
fe262d5c | 935 | static struct attribute *cpufreq_attrs[] = { |
1da177e4 LT |
936 | &cpuinfo_min_freq.attr, |
937 | &cpuinfo_max_freq.attr, | |
ed129784 | 938 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
939 | &scaling_min_freq.attr, |
940 | &scaling_max_freq.attr, | |
941 | &affected_cpus.attr, | |
e8628dd0 | 942 | &related_cpus.attr, |
1da177e4 LT |
943 | &scaling_governor.attr, |
944 | &scaling_driver.attr, | |
945 | &scaling_available_governors.attr, | |
9e76988e | 946 | &scaling_setspeed.attr, |
1da177e4 LT |
947 | NULL |
948 | }; | |
fe262d5c | 949 | ATTRIBUTE_GROUPS(cpufreq); |
1da177e4 | 950 | |
29464f28 DJ |
951 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
952 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 953 | |
29464f28 | 954 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 955 | { |
905d77cd DJ |
956 | struct cpufreq_policy *policy = to_policy(kobj); |
957 | struct freq_attr *fattr = to_attr(attr); | |
d4627a28 | 958 | ssize_t ret = -EBUSY; |
6eed9404 | 959 | |
e6e8df07 KS |
960 | if (!fattr->show) |
961 | return -EIO; | |
962 | ||
ad7722da | 963 | down_read(&policy->rwsem); |
d4627a28 SS |
964 | if (likely(!policy_is_inactive(policy))) |
965 | ret = fattr->show(policy, buf); | |
ad7722da | 966 | up_read(&policy->rwsem); |
1b750e3b | 967 | |
1da177e4 LT |
968 | return ret; |
969 | } | |
970 | ||
905d77cd DJ |
971 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
972 | const char *buf, size_t count) | |
1da177e4 | 973 | { |
905d77cd DJ |
974 | struct cpufreq_policy *policy = to_policy(kobj); |
975 | struct freq_attr *fattr = to_attr(attr); | |
d4627a28 | 976 | ssize_t ret = -EBUSY; |
6eed9404 | 977 | |
e6e8df07 KS |
978 | if (!fattr->store) |
979 | return -EIO; | |
980 | ||
9ab9b9d3 VK |
981 | down_write(&policy->rwsem); |
982 | if (likely(!policy_is_inactive(policy))) | |
983 | ret = fattr->store(policy, buf, count); | |
984 | up_write(&policy->rwsem); | |
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 | ||
108fcad9 | 1001 | static const struct kobj_type ktype_cpufreq = { |
1da177e4 | 1002 | .sysfs_ops = &sysfs_ops, |
fe262d5c | 1003 | .default_groups = cpufreq_groups, |
1da177e4 LT |
1004 | .release = cpufreq_sysfs_release, |
1005 | }; | |
1006 | ||
2c1b5a84 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 | ||
5c84c1b8 | 1021 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu, |
26619804 | 1022 | struct device *dev) |
87549141 | 1023 | { |
26619804 VK |
1024 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1025 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
5c84c1b8 | 1026 | cpumask_clear_cpu(cpu, policy->real_cpus); |
87549141 VK |
1027 | } |
1028 | ||
d9612a49 | 1029 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
1030 | { |
1031 | struct freq_attr **drv_attr; | |
909a694e | 1032 | int ret = 0; |
909a694e | 1033 | |
909a694e | 1034 | /* set up files for this cpu device */ |
1c3d85dd | 1035 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1036 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1037 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1038 | if (ret) | |
6d4e81ed | 1039 | return ret; |
909a694e DJ |
1040 | drv_attr++; |
1041 | } | |
1c3d85dd | 1042 | if (cpufreq_driver->get) { |
909a694e DJ |
1043 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1044 | if (ret) | |
6d4e81ed | 1045 | return ret; |
909a694e | 1046 | } |
c034b02e DB |
1047 | |
1048 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1049 | if (ret) | |
6d4e81ed | 1050 | return ret; |
c034b02e | 1051 | |
1c3d85dd | 1052 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1053 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1054 | if (ret) | |
6d4e81ed | 1055 | return ret; |
e2f74f35 | 1056 | } |
909a694e | 1057 | |
26619804 | 1058 | return 0; |
e18f1682 SB |
1059 | } |
1060 | ||
7f0fa40f | 1061 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1062 | { |
1e4f63ae RW |
1063 | struct cpufreq_governor *gov = NULL; |
1064 | unsigned int pol = CPUFREQ_POLICY_UNKNOWN; | |
8cc46ae5 | 1065 | int ret; |
ab05d97a YH |
1066 | |
1067 | if (has_target()) { | |
1e4f63ae | 1068 | /* Update policy governor to the one used before hotplug. */ |
8cc46ae5 | 1069 | gov = get_governor(policy->last_governor); |
ab05d97a YH |
1070 | if (gov) { |
1071 | pr_debug("Restoring governor %s for cpu %d\n", | |
8412b456 | 1072 | gov->name, policy->cpu); |
1e4f63ae | 1073 | } else { |
8412b456 QP |
1074 | gov = get_governor(default_governor); |
1075 | } | |
1076 | ||
1077 | if (!gov) { | |
1078 | gov = cpufreq_default_governor(); | |
8412b456 | 1079 | __module_get(gov->owner); |
ab05d97a | 1080 | } |
8412b456 | 1081 | |
de1df26b | 1082 | } else { |
8412b456 | 1083 | |
ab05d97a YH |
1084 | /* Use the default policy if there is no last_policy. */ |
1085 | if (policy->last_policy) { | |
1e4f63ae | 1086 | pol = policy->last_policy; |
8412b456 QP |
1087 | } else { |
1088 | pol = cpufreq_parse_policy(default_governor); | |
f5739cb0 | 1089 | /* |
8412b456 | 1090 | * In case the default governor is neither "performance" |
f5739cb0 RW |
1091 | * nor "powersave", fall back to the initial policy |
1092 | * value set by the driver. | |
1093 | */ | |
1094 | if (pol == CPUFREQ_POLICY_UNKNOWN) | |
1095 | pol = policy->policy; | |
ab05d97a | 1096 | } |
f5739cb0 RW |
1097 | if (pol != CPUFREQ_POLICY_PERFORMANCE && |
1098 | pol != CPUFREQ_POLICY_POWERSAVE) | |
1099 | return -ENODATA; | |
69030dd1 | 1100 | } |
ab05d97a | 1101 | |
8cc46ae5 VK |
1102 | ret = cpufreq_set_policy(policy, gov, pol); |
1103 | if (gov) | |
1104 | module_put(gov->owner); | |
1105 | ||
1106 | return ret; | |
909a694e DJ |
1107 | } |
1108 | ||
d9612a49 | 1109 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1110 | { |
9c0ebcf7 | 1111 | int ret = 0; |
fcf80582 | 1112 | |
bb29ae15 VK |
1113 | /* Has this CPU been taken care of already? */ |
1114 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1115 | return 0; | |
1116 | ||
49f18560 | 1117 | down_write(&policy->rwsem); |
45482c70 RW |
1118 | if (has_target()) |
1119 | cpufreq_stop_governor(policy); | |
fcf80582 | 1120 | |
fcf80582 | 1121 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1122 | |
9c0ebcf7 | 1123 | if (has_target()) { |
0a300767 | 1124 | ret = cpufreq_start_governor(policy); |
49f18560 | 1125 | if (ret) |
3de9bdeb | 1126 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1127 | } |
49f18560 VK |
1128 | up_write(&policy->rwsem); |
1129 | return ret; | |
fcf80582 | 1130 | } |
1da177e4 | 1131 | |
c57b25bd | 1132 | void refresh_frequency_limits(struct cpufreq_policy *policy) |
70a59fde | 1133 | { |
67d874c3 | 1134 | if (!policy_is_inactive(policy)) { |
67d874c3 | 1135 | pr_debug("updating policy for CPU %u\n", policy->cpu); |
70a59fde | 1136 | |
1e4f63ae | 1137 | cpufreq_set_policy(policy, policy->governor, policy->policy); |
67d874c3 | 1138 | } |
70a59fde | 1139 | } |
c57b25bd | 1140 | EXPORT_SYMBOL(refresh_frequency_limits); |
70a59fde | 1141 | |
11eb69b9 VK |
1142 | static void handle_update(struct work_struct *work) |
1143 | { | |
1144 | struct cpufreq_policy *policy = | |
1145 | container_of(work, struct cpufreq_policy, update); | |
70a59fde VK |
1146 | |
1147 | pr_debug("handle_update for cpu %u called\n", policy->cpu); | |
67d874c3 | 1148 | down_write(&policy->rwsem); |
70a59fde | 1149 | refresh_frequency_limits(policy); |
67d874c3 VK |
1150 | up_write(&policy->rwsem); |
1151 | } | |
1152 | ||
1153 | static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq, | |
1154 | void *data) | |
1155 | { | |
1156 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min); | |
1157 | ||
1158 | schedule_work(&policy->update); | |
1159 | return 0; | |
1160 | } | |
1161 | ||
1162 | static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq, | |
1163 | void *data) | |
1164 | { | |
1165 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max); | |
1166 | ||
1167 | schedule_work(&policy->update); | |
1168 | return 0; | |
1169 | } | |
1170 | ||
1171 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) | |
1172 | { | |
1173 | struct kobject *kobj; | |
1174 | struct completion *cmp; | |
1175 | ||
1176 | down_write(&policy->rwsem); | |
1177 | cpufreq_stats_free_table(policy); | |
1178 | kobj = &policy->kobj; | |
1179 | cmp = &policy->kobj_unregister; | |
1180 | up_write(&policy->rwsem); | |
1181 | kobject_put(kobj); | |
1182 | ||
1183 | /* | |
1184 | * We need to make sure that the underlying kobj is | |
1185 | * actually not referenced anymore by anybody before we | |
1186 | * proceed with unloading. | |
1187 | */ | |
1188 | pr_debug("waiting for dropping of refcount\n"); | |
1189 | wait_for_completion(cmp); | |
1190 | pr_debug("wait complete\n"); | |
fcf80582 | 1191 | } |
1da177e4 | 1192 | |
a34e63b1 | 1193 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1194 | { |
1195 | struct cpufreq_policy *policy; | |
67d874c3 | 1196 | struct device *dev = get_cpu_device(cpu); |
edd4a893 | 1197 | int ret; |
e9698cc5 | 1198 | |
67d874c3 VK |
1199 | if (!dev) |
1200 | return NULL; | |
1201 | ||
e9698cc5 SB |
1202 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1203 | if (!policy) | |
1204 | return NULL; | |
1205 | ||
1206 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1207 | goto err_free_policy; | |
1208 | ||
1209 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1210 | goto err_free_cpumask; | |
1211 | ||
559ed407 RW |
1212 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1213 | goto err_free_rcpumask; | |
1214 | ||
5c510548 | 1215 | init_completion(&policy->kobj_unregister); |
edd4a893 VK |
1216 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1217 | cpufreq_global_kobject, "policy%u", cpu); | |
1218 | if (ret) { | |
67d874c3 | 1219 | dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret); |
2acb9bda RW |
1220 | /* |
1221 | * The entire policy object will be freed below, but the extra | |
1222 | * memory allocated for the kobject name needs to be freed by | |
1223 | * releasing the kobject. | |
1224 | */ | |
4ebe36c9 | 1225 | kobject_put(&policy->kobj); |
edd4a893 VK |
1226 | goto err_free_real_cpus; |
1227 | } | |
1228 | ||
3000ce3c RW |
1229 | freq_constraints_init(&policy->constraints); |
1230 | ||
67d874c3 VK |
1231 | policy->nb_min.notifier_call = cpufreq_notifier_min; |
1232 | policy->nb_max.notifier_call = cpufreq_notifier_max; | |
1233 | ||
3000ce3c RW |
1234 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MIN, |
1235 | &policy->nb_min); | |
67d874c3 VK |
1236 | if (ret) { |
1237 | dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n", | |
1238 | ret, cpumask_pr_args(policy->cpus)); | |
1239 | goto err_kobj_remove; | |
1240 | } | |
1241 | ||
3000ce3c RW |
1242 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MAX, |
1243 | &policy->nb_max); | |
67d874c3 VK |
1244 | if (ret) { |
1245 | dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n", | |
1246 | ret, cpumask_pr_args(policy->cpus)); | |
1247 | goto err_min_qos_notifier; | |
1248 | } | |
1249 | ||
c88a1f8b | 1250 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1251 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1252 | spin_lock_init(&policy->transition_lock); |
1253 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 | 1254 | INIT_WORK(&policy->update, handle_update); |
ad7722da | 1255 | |
a34e63b1 | 1256 | policy->cpu = cpu; |
e9698cc5 SB |
1257 | return policy; |
1258 | ||
67d874c3 | 1259 | err_min_qos_notifier: |
3000ce3c RW |
1260 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, |
1261 | &policy->nb_min); | |
67d874c3 VK |
1262 | err_kobj_remove: |
1263 | cpufreq_policy_put_kobj(policy); | |
edd4a893 VK |
1264 | err_free_real_cpus: |
1265 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1266 | err_free_rcpumask: |
1267 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1268 | err_free_cpumask: |
1269 | free_cpumask_var(policy->cpus); | |
1270 | err_free_policy: | |
1271 | kfree(policy); | |
1272 | ||
1273 | return NULL; | |
1274 | } | |
1275 | ||
f9f41e3e | 1276 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1277 | { |
988bed09 VK |
1278 | unsigned long flags; |
1279 | int cpu; | |
1280 | ||
a2f6a7ac VK |
1281 | /* |
1282 | * The callers must ensure the policy is inactive by now, to avoid any | |
1283 | * races with show()/store() callbacks. | |
1284 | */ | |
1285 | if (unlikely(!policy_is_inactive(policy))) | |
1286 | pr_warn("%s: Freeing active policy\n", __func__); | |
1287 | ||
988bed09 VK |
1288 | /* Remove policy from list */ |
1289 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1290 | list_del(&policy->policy_list); | |
1291 | ||
1292 | for_each_cpu(cpu, policy->related_cpus) | |
1293 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1294 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1295 | ||
3000ce3c RW |
1296 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MAX, |
1297 | &policy->nb_max); | |
1298 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, | |
1299 | &policy->nb_min); | |
6a149036 | 1300 | |
6941051d SH |
1301 | /* Cancel any pending policy->update work before freeing the policy. */ |
1302 | cancel_work_sync(&policy->update); | |
6a149036 VK |
1303 | |
1304 | if (policy->max_freq_req) { | |
1305 | /* | |
1e81d3e0 TY |
1306 | * Remove max_freq_req after sending CPUFREQ_REMOVE_POLICY |
1307 | * notification, since CPUFREQ_CREATE_POLICY notification was | |
1308 | * sent after adding max_freq_req earlier. | |
6a149036 VK |
1309 | */ |
1310 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1311 | CPUFREQ_REMOVE_POLICY, policy); | |
3000ce3c | 1312 | freq_qos_remove_request(policy->max_freq_req); |
6a149036 VK |
1313 | } |
1314 | ||
3000ce3c | 1315 | freq_qos_remove_request(policy->min_freq_req); |
18c49926 | 1316 | kfree(policy->min_freq_req); |
67d874c3 | 1317 | |
f9f41e3e | 1318 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1319 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1320 | free_cpumask_var(policy->related_cpus); |
1321 | free_cpumask_var(policy->cpus); | |
1322 | kfree(policy); | |
1323 | } | |
1324 | ||
0b275352 | 1325 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1326 | { |
7f0c020a | 1327 | struct cpufreq_policy *policy; |
194d99c7 | 1328 | bool new_policy; |
1da177e4 | 1329 | unsigned long flags; |
0b275352 RW |
1330 | unsigned int j; |
1331 | int ret; | |
87549141 | 1332 | |
0b275352 | 1333 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1334 | |
bb29ae15 | 1335 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1336 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1337 | if (policy) { |
9104bb26 | 1338 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1339 | if (!policy_is_inactive(policy)) |
d9612a49 | 1340 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1341 | |
11ce707e | 1342 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1343 | new_policy = false; |
11ce707e RW |
1344 | down_write(&policy->rwsem); |
1345 | policy->cpu = cpu; | |
1346 | policy->governor = NULL; | |
11ce707e | 1347 | } else { |
194d99c7 | 1348 | new_policy = true; |
a34e63b1 | 1349 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1350 | if (!policy) |
d4d854d6 | 1351 | return -ENOMEM; |
514ff1bc | 1352 | down_write(&policy->rwsem); |
72368d12 | 1353 | } |
0d66b91e | 1354 | |
91a12e91 | 1355 | if (!new_policy && cpufreq_driver->online) { |
68315f1a PG |
1356 | /* Recover policy->cpus using related_cpus */ |
1357 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1358 | ||
91a12e91 VK |
1359 | ret = cpufreq_driver->online(policy); |
1360 | if (ret) { | |
1361 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1362 | __LINE__); | |
1363 | goto out_exit_policy; | |
1364 | } | |
91a12e91 VK |
1365 | } else { |
1366 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1367 | |
91a12e91 VK |
1368 | /* |
1369 | * Call driver. From then on the cpufreq must be able | |
1370 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1371 | */ | |
1372 | ret = cpufreq_driver->init(policy); | |
1373 | if (ret) { | |
1374 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1375 | __LINE__); | |
1376 | goto out_free_policy; | |
1377 | } | |
d417e069 | 1378 | |
3b718057 RW |
1379 | /* |
1380 | * The initialization has succeeded and the policy is online. | |
1381 | * If there is a problem with its frequency table, take it | |
1382 | * offline and drop it. | |
1383 | */ | |
91a12e91 VK |
1384 | ret = cpufreq_table_validate_and_sort(policy); |
1385 | if (ret) | |
3b718057 | 1386 | goto out_offline_policy; |
6d4e81ed | 1387 | |
4d1f3a5b | 1388 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1389 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1390 | } |
559ed407 | 1391 | |
5a7e56a5 VK |
1392 | /* |
1393 | * affected cpus must always be the one, which are online. We aren't | |
1394 | * managing offline cpus here. | |
1395 | */ | |
1396 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1397 | ||
194d99c7 | 1398 | if (new_policy) { |
2f0ba790 | 1399 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1400 | per_cpu(cpufreq_cpu_data, j) = policy; |
2c1b5a84 | 1401 | add_cpu_dev_symlink(policy, j, get_cpu_device(j)); |
2f0ba790 | 1402 | } |
18c49926 VK |
1403 | |
1404 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1405 | GFP_KERNEL); | |
b96f0384 WS |
1406 | if (!policy->min_freq_req) { |
1407 | ret = -ENOMEM; | |
18c49926 | 1408 | goto out_destroy_policy; |
b96f0384 | 1409 | } |
18c49926 | 1410 | |
3000ce3c RW |
1411 | ret = freq_qos_add_request(&policy->constraints, |
1412 | policy->min_freq_req, FREQ_QOS_MIN, | |
521223d8 | 1413 | FREQ_QOS_MIN_DEFAULT_VALUE); |
18c49926 VK |
1414 | if (ret < 0) { |
1415 | /* | |
3000ce3c | 1416 | * So we don't call freq_qos_remove_request() for an |
18c49926 VK |
1417 | * uninitialized request. |
1418 | */ | |
1419 | kfree(policy->min_freq_req); | |
1420 | policy->min_freq_req = NULL; | |
18c49926 VK |
1421 | goto out_destroy_policy; |
1422 | } | |
1423 | ||
1424 | /* | |
1425 | * This must be initialized right here to avoid calling | |
3000ce3c | 1426 | * freq_qos_remove_request() on uninitialized request in case |
18c49926 VK |
1427 | * of errors. |
1428 | */ | |
1429 | policy->max_freq_req = policy->min_freq_req + 1; | |
1430 | ||
3000ce3c RW |
1431 | ret = freq_qos_add_request(&policy->constraints, |
1432 | policy->max_freq_req, FREQ_QOS_MAX, | |
521223d8 | 1433 | FREQ_QOS_MAX_DEFAULT_VALUE); |
18c49926 VK |
1434 | if (ret < 0) { |
1435 | policy->max_freq_req = NULL; | |
18c49926 VK |
1436 | goto out_destroy_policy; |
1437 | } | |
6a149036 VK |
1438 | |
1439 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1440 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1441 | } |
652ed95d | 1442 | |
5ddc6d4e | 1443 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1444 | policy->cur = cpufreq_driver->get(policy->cpu); |
1445 | if (!policy->cur) { | |
b96f0384 | 1446 | ret = -EIO; |
da60ce9f | 1447 | pr_err("%s: ->get() failed\n", __func__); |
d417e069 | 1448 | goto out_destroy_policy; |
da60ce9f VK |
1449 | } |
1450 | } | |
1451 | ||
d3916691 VK |
1452 | /* |
1453 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1454 | * frequency table present with cpufreq core. In such cases CPU might be | |
1455 | * unstable if it has to run on that frequency for long duration of time | |
1456 | * and so its better to set it to a frequency which is specified in | |
1457 | * freq-table. This also makes cpufreq stats inconsistent as | |
1458 | * cpufreq-stats would fail to register because current frequency of CPU | |
1459 | * isn't found in freq-table. | |
1460 | * | |
1461 | * Because we don't want this change to effect boot process badly, we go | |
1462 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1463 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1464 | * is initialized to zero). | |
1465 | * | |
1466 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1467 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1468 | * equal to target-freq. | |
1469 | */ | |
1470 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1471 | && has_target()) { | |
97148d0a VK |
1472 | unsigned int old_freq = policy->cur; |
1473 | ||
d3916691 | 1474 | /* Are we running at unknown frequency ? */ |
97148d0a | 1475 | ret = cpufreq_frequency_table_get_index(policy, old_freq); |
d3916691 | 1476 | if (ret == -EINVAL) { |
97148d0a VK |
1477 | ret = __cpufreq_driver_target(policy, old_freq - 1, |
1478 | CPUFREQ_RELATION_L); | |
d3916691 VK |
1479 | |
1480 | /* | |
1481 | * Reaching here after boot in a few seconds may not | |
1482 | * mean that system will remain stable at "unknown" | |
1483 | * frequency for longer duration. Hence, a BUG_ON(). | |
1484 | */ | |
1485 | BUG_ON(ret); | |
97148d0a VK |
1486 | pr_info("%s: CPU%d: Running at unlisted initial frequency: %u KHz, changing to: %u KHz\n", |
1487 | __func__, policy->cpu, old_freq, policy->cur); | |
d3916691 VK |
1488 | } |
1489 | } | |
1490 | ||
194d99c7 | 1491 | if (new_policy) { |
d9612a49 | 1492 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1493 | if (ret) |
d417e069 | 1494 | goto out_destroy_policy; |
1aefc75b RW |
1495 | |
1496 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1497 | |
988bed09 VK |
1498 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1499 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1500 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
c17495b0 VK |
1501 | |
1502 | /* | |
1503 | * Register with the energy model before | |
1504 | * sched_cpufreq_governor_change() is called, which will result | |
1505 | * in rebuilding of the sched domains, which should only be done | |
1506 | * once the energy model is properly initialized for the policy | |
1507 | * first. | |
1508 | * | |
1509 | * Also, this should be called before the policy is registered | |
1510 | * with cooling framework. | |
1511 | */ | |
1512 | if (cpufreq_driver->register_em) | |
1513 | cpufreq_driver->register_em(policy); | |
988bed09 | 1514 | } |
9515f4d6 | 1515 | |
7f0fa40f VK |
1516 | ret = cpufreq_init_policy(policy); |
1517 | if (ret) { | |
1518 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1519 | __func__, cpu, ret); | |
d417e069 | 1520 | goto out_destroy_policy; |
08fd8c1c | 1521 | } |
e18f1682 | 1522 | |
4e97b631 | 1523 | up_write(&policy->rwsem); |
08fd8c1c | 1524 | |
038c5b3e | 1525 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1526 | |
4f774c4a BA |
1527 | /* Callback for handling stuff after policy is ready */ |
1528 | if (cpufreq_driver->ready) | |
1529 | cpufreq_driver->ready(policy); | |
1530 | ||
bcc61569 | 1531 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1532 | policy->cdev = of_cpufreq_cooling_register(policy); |
1533 | ||
2d06d8c4 | 1534 | pr_debug("initialization complete\n"); |
87c32271 | 1535 | |
1da177e4 LT |
1536 | return 0; |
1537 | ||
d417e069 | 1538 | out_destroy_policy: |
b24b6478 | 1539 | for_each_cpu(j, policy->real_cpus) |
5c84c1b8 | 1540 | remove_cpu_dev_symlink(policy, j, get_cpu_device(j)); |
b24b6478 | 1541 | |
3b718057 RW |
1542 | out_offline_policy: |
1543 | if (cpufreq_driver->offline) | |
1544 | cpufreq_driver->offline(policy); | |
1545 | ||
d417e069 | 1546 | out_exit_policy: |
da60ce9f VK |
1547 | if (cpufreq_driver->exit) |
1548 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1549 | |
8101f997 | 1550 | out_free_policy: |
a2f6a7ac | 1551 | cpumask_clear(policy->cpus); |
514ff1bc SS |
1552 | up_write(&policy->rwsem); |
1553 | ||
f9f41e3e | 1554 | cpufreq_policy_free(policy); |
1da177e4 LT |
1555 | return ret; |
1556 | } | |
1557 | ||
0b275352 RW |
1558 | /** |
1559 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1560 | * @dev: CPU device. | |
1561 | * @sif: Subsystem interface structure pointer (not used) | |
1562 | */ | |
1563 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1564 | { | |
a794d613 | 1565 | struct cpufreq_policy *policy; |
0b275352 | 1566 | unsigned cpu = dev->id; |
26619804 | 1567 | int ret; |
0b275352 RW |
1568 | |
1569 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1570 | ||
26619804 VK |
1571 | if (cpu_online(cpu)) { |
1572 | ret = cpufreq_online(cpu); | |
1573 | if (ret) | |
1574 | return ret; | |
1575 | } | |
0b275352 | 1576 | |
26619804 | 1577 | /* Create sysfs link on CPU registration */ |
a794d613 | 1578 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 | 1579 | if (policy) |
2c1b5a84 | 1580 | add_cpu_dev_symlink(policy, cpu, dev); |
26619804 | 1581 | |
2f0ba790 | 1582 | return 0; |
1da177e4 LT |
1583 | } |
1584 | ||
fddd8f86 | 1585 | static void __cpufreq_offline(unsigned int cpu, struct cpufreq_policy *policy) |
1da177e4 | 1586 | { |
69cee714 | 1587 | int ret; |
1da177e4 | 1588 | |
45482c70 RW |
1589 | if (has_target()) |
1590 | cpufreq_stop_governor(policy); | |
1da177e4 | 1591 | |
9591becb | 1592 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1593 | |
9591becb | 1594 | if (!policy_is_inactive(policy)) { |
e1e962c5 RW |
1595 | /* Nominate a new CPU if necessary. */ |
1596 | if (cpu == policy->cpu) | |
1597 | policy->cpu = cpumask_any(policy->cpus); | |
1598 | ||
1599 | /* Start the governor again for the active policy. */ | |
9591becb | 1600 | if (has_target()) { |
0a300767 | 1601 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1602 | if (ret) |
1603 | pr_err("%s: Failed to start governor\n", __func__); | |
1604 | } | |
cedb70af | 1605 | |
fddd8f86 | 1606 | return; |
cedb70af SB |
1607 | } |
1608 | ||
e1e962c5 RW |
1609 | if (has_target()) |
1610 | strncpy(policy->last_governor, policy->governor->name, | |
1611 | CPUFREQ_NAME_LEN); | |
1612 | else | |
1613 | policy->last_policy = policy->policy; | |
1614 | ||
bcc61569 | 1615 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1616 | cpufreq_cooling_unregister(policy->cdev); |
1617 | policy->cdev = NULL; | |
1618 | } | |
1619 | ||
36be3418 RW |
1620 | if (has_target()) |
1621 | cpufreq_exit_governor(policy); | |
1da177e4 | 1622 | |
87549141 | 1623 | /* |
91a12e91 VK |
1624 | * Perform the ->offline() during light-weight tear-down, as |
1625 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1626 | */ |
91a12e91 VK |
1627 | if (cpufreq_driver->offline) { |
1628 | cpufreq_driver->offline(policy); | |
1629 | } else if (cpufreq_driver->exit) { | |
87549141 | 1630 | cpufreq_driver->exit(policy); |
55582bcc SP |
1631 | policy->freq_table = NULL; |
1632 | } | |
fddd8f86 RW |
1633 | } |
1634 | ||
1635 | static int cpufreq_offline(unsigned int cpu) | |
1636 | { | |
1637 | struct cpufreq_policy *policy; | |
1638 | ||
1639 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); | |
1640 | ||
1641 | policy = cpufreq_cpu_get_raw(cpu); | |
1642 | if (!policy) { | |
1643 | pr_debug("%s: No cpu_data found\n", __func__); | |
1644 | return 0; | |
1645 | } | |
1646 | ||
1647 | down_write(&policy->rwsem); | |
1648 | ||
1649 | __cpufreq_offline(cpu, policy); | |
49f18560 | 1650 | |
49f18560 | 1651 | up_write(&policy->rwsem); |
27622b06 | 1652 | return 0; |
1da177e4 LT |
1653 | } |
1654 | ||
a9909c21 | 1655 | /* |
27a862e9 | 1656 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1657 | * |
1658 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1659 | */ |
71db87ba | 1660 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1661 | { |
8a25a2fd | 1662 | unsigned int cpu = dev->id; |
559ed407 | 1663 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1664 | |
559ed407 | 1665 | if (!policy) |
1af115d6 | 1666 | return; |
87549141 | 1667 | |
f339f354 RW |
1668 | down_write(&policy->rwsem); |
1669 | ||
69cee714 | 1670 | if (cpu_online(cpu)) |
f339f354 | 1671 | __cpufreq_offline(cpu, policy); |
87549141 | 1672 | |
5c84c1b8 | 1673 | remove_cpu_dev_symlink(policy, cpu, dev); |
87549141 | 1674 | |
f339f354 RW |
1675 | if (!cpumask_empty(policy->real_cpus)) { |
1676 | up_write(&policy->rwsem); | |
1677 | return; | |
91a12e91 | 1678 | } |
f339f354 RW |
1679 | |
1680 | /* We did light-weight exit earlier, do full tear down now */ | |
1681 | if (cpufreq_driver->offline) | |
1682 | cpufreq_driver->exit(policy); | |
1683 | ||
1684 | up_write(&policy->rwsem); | |
1685 | ||
1686 | cpufreq_policy_free(policy); | |
5a01f2e8 VP |
1687 | } |
1688 | ||
1da177e4 | 1689 | /** |
ec06e586 RW |
1690 | * cpufreq_out_of_sync - Fix up actual and saved CPU frequency difference. |
1691 | * @policy: Policy managing CPUs. | |
1692 | * @new_freq: New CPU frequency. | |
1da177e4 | 1693 | * |
ec06e586 RW |
1694 | * Adjust to the current frequency first and clean up later by either calling |
1695 | * cpufreq_update_policy(), or scheduling handle_update(). | |
1da177e4 | 1696 | */ |
a1e1dc41 | 1697 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1698 | unsigned int new_freq) |
1da177e4 LT |
1699 | { |
1700 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1701 | |
e837f9b5 | 1702 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1703 | policy->cur, new_freq); |
1da177e4 | 1704 | |
a1e1dc41 | 1705 | freqs.old = policy->cur; |
1da177e4 | 1706 | freqs.new = new_freq; |
b43a7ffb | 1707 | |
8fec051e VK |
1708 | cpufreq_freq_transition_begin(policy, &freqs); |
1709 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1710 | } |
1711 | ||
5980752e VK |
1712 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1713 | { | |
1714 | unsigned int new_freq; | |
1715 | ||
1716 | new_freq = cpufreq_driver->get(policy->cpu); | |
1717 | if (!new_freq) | |
1718 | return 0; | |
1719 | ||
1720 | /* | |
1721 | * If fast frequency switching is used with the given policy, the check | |
1722 | * against policy->cur is pointless, so skip it in that case. | |
1723 | */ | |
1724 | if (policy->fast_switch_enabled || !has_target()) | |
1725 | return new_freq; | |
1726 | ||
1727 | if (policy->cur != new_freq) { | |
f55ae08c VK |
1728 | /* |
1729 | * For some platforms, the frequency returned by hardware may be | |
1730 | * slightly different from what is provided in the frequency | |
1731 | * table, for example hardware may return 499 MHz instead of 500 | |
1732 | * MHz. In such cases it is better to avoid getting into | |
1733 | * unnecessary frequency updates. | |
1734 | */ | |
44295af5 | 1735 | if (abs(policy->cur - new_freq) < KHZ_PER_MHZ) |
f55ae08c VK |
1736 | return policy->cur; |
1737 | ||
5980752e VK |
1738 | cpufreq_out_of_sync(policy, new_freq); |
1739 | if (update) | |
1740 | schedule_work(&policy->update); | |
1741 | } | |
1742 | ||
1743 | return new_freq; | |
1744 | } | |
1745 | ||
32ee8c3e | 1746 | /** |
4ab70df4 | 1747 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1748 | * @cpu: CPU number |
1749 | * | |
1750 | * This is the last known freq, without actually getting it from the driver. | |
1751 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1752 | */ | |
1753 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1754 | { | |
9e21ba8b | 1755 | struct cpufreq_policy *policy; |
e08f5f5b | 1756 | unsigned int ret_freq = 0; |
c75361c0 | 1757 | unsigned long flags; |
95235ca2 | 1758 | |
c75361c0 RC |
1759 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1760 | ||
1761 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1762 | ret_freq = cpufreq_driver->get(cpu); | |
1763 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1764 | return ret_freq; | |
1765 | } | |
1766 | ||
1767 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1768 | |
1769 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1770 | if (policy) { |
e08f5f5b | 1771 | ret_freq = policy->cur; |
95235ca2 VP |
1772 | cpufreq_cpu_put(policy); |
1773 | } | |
1774 | ||
4d34a67d | 1775 | return ret_freq; |
95235ca2 VP |
1776 | } |
1777 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1778 | ||
3d737108 JB |
1779 | /** |
1780 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1781 | * @cpu: CPU number | |
1782 | * | |
1783 | * Just return the max possible frequency for a given CPU. | |
1784 | */ | |
1785 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1786 | { | |
1787 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1788 | unsigned int ret_freq = 0; | |
1789 | ||
1790 | if (policy) { | |
1791 | ret_freq = policy->max; | |
1792 | cpufreq_cpu_put(policy); | |
1793 | } | |
1794 | ||
1795 | return ret_freq; | |
1796 | } | |
1797 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1798 | ||
bbce8eaa IV |
1799 | /** |
1800 | * cpufreq_get_hw_max_freq - get the max hardware frequency of the CPU | |
1801 | * @cpu: CPU number | |
1802 | * | |
1803 | * The default return value is the max_freq field of cpuinfo. | |
1804 | */ | |
1805 | __weak unsigned int cpufreq_get_hw_max_freq(unsigned int cpu) | |
1806 | { | |
1807 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1808 | unsigned int ret_freq = 0; | |
1809 | ||
1810 | if (policy) { | |
1811 | ret_freq = policy->cpuinfo.max_freq; | |
1812 | cpufreq_cpu_put(policy); | |
1813 | } | |
1814 | ||
1815 | return ret_freq; | |
1816 | } | |
1817 | EXPORT_SYMBOL(cpufreq_get_hw_max_freq); | |
1818 | ||
d92d50a4 | 1819 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1820 | { |
4db7c34c | 1821 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1822 | return 0; |
1da177e4 | 1823 | |
5980752e | 1824 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1825 | } |
1da177e4 | 1826 | |
5a01f2e8 VP |
1827 | /** |
1828 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1829 | * @cpu: CPU number | |
1830 | * | |
1831 | * Get the CPU current (static) CPU frequency | |
1832 | */ | |
1833 | unsigned int cpufreq_get(unsigned int cpu) | |
1834 | { | |
999976e0 | 1835 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1836 | unsigned int ret_freq = 0; |
5a01f2e8 | 1837 | |
999976e0 AP |
1838 | if (policy) { |
1839 | down_read(&policy->rwsem); | |
4db7c34c YH |
1840 | if (cpufreq_driver->get) |
1841 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1842 | up_read(&policy->rwsem); |
5a01f2e8 | 1843 | |
999976e0 AP |
1844 | cpufreq_cpu_put(policy); |
1845 | } | |
6eed9404 | 1846 | |
4d34a67d | 1847 | return ret_freq; |
1da177e4 LT |
1848 | } |
1849 | EXPORT_SYMBOL(cpufreq_get); | |
1850 | ||
8a25a2fd KS |
1851 | static struct subsys_interface cpufreq_interface = { |
1852 | .name = "cpufreq", | |
1853 | .subsys = &cpu_subsys, | |
1854 | .add_dev = cpufreq_add_dev, | |
1855 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1856 | }; |
1857 | ||
e28867ea VK |
1858 | /* |
1859 | * In case platform wants some specific frequency to be configured | |
1860 | * during suspend.. | |
1861 | */ | |
1862 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1863 | { | |
1864 | int ret; | |
1865 | ||
1866 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1867 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1868 | return 0; | |
e28867ea VK |
1869 | } |
1870 | ||
1871 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1872 | policy->suspend_freq); | |
1873 | ||
1874 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1875 | CPUFREQ_RELATION_H); | |
1876 | if (ret) | |
1877 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1878 | __func__, policy->suspend_freq, ret); | |
1879 | ||
1880 | return ret; | |
1881 | } | |
1882 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1883 | ||
42d4dc3f | 1884 | /** |
ec06e586 | 1885 | * cpufreq_suspend() - Suspend CPUFreq governors. |
e00e56df | 1886 | * |
2f0aea93 VK |
1887 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1888 | * as some platforms can't change frequency after this point in suspend cycle. | |
1889 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1890 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1891 | */ |
2f0aea93 | 1892 | void cpufreq_suspend(void) |
42d4dc3f | 1893 | { |
3a3e9e06 | 1894 | struct cpufreq_policy *policy; |
42d4dc3f | 1895 | |
2f0aea93 VK |
1896 | if (!cpufreq_driver) |
1897 | return; | |
42d4dc3f | 1898 | |
ba41e1bc | 1899 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1900 | goto suspend; |
42d4dc3f | 1901 | |
2f0aea93 VK |
1902 | pr_debug("%s: Suspending Governors\n", __func__); |
1903 | ||
f963735a | 1904 | for_each_active_policy(policy) { |
ba41e1bc RW |
1905 | if (has_target()) { |
1906 | down_write(&policy->rwsem); | |
45482c70 | 1907 | cpufreq_stop_governor(policy); |
ba41e1bc | 1908 | up_write(&policy->rwsem); |
ba41e1bc RW |
1909 | } |
1910 | ||
1911 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1912 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1913 | cpufreq_driver->name); | |
42d4dc3f | 1914 | } |
b1b12bab VK |
1915 | |
1916 | suspend: | |
1917 | cpufreq_suspended = true; | |
42d4dc3f BH |
1918 | } |
1919 | ||
1da177e4 | 1920 | /** |
ec06e586 | 1921 | * cpufreq_resume() - Resume CPUFreq governors. |
1da177e4 | 1922 | * |
2f0aea93 VK |
1923 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1924 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1925 | */ |
2f0aea93 | 1926 | void cpufreq_resume(void) |
1da177e4 | 1927 | { |
3a3e9e06 | 1928 | struct cpufreq_policy *policy; |
49f18560 | 1929 | int ret; |
1da177e4 | 1930 | |
2f0aea93 | 1931 | if (!cpufreq_driver) |
703cbaa6 BY |
1932 | return; |
1933 | ||
1934 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1935 | return; |
1da177e4 | 1936 | |
8e30444e LT |
1937 | cpufreq_suspended = false; |
1938 | ||
ba41e1bc | 1939 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1940 | return; |
1da177e4 | 1941 | |
2f0aea93 | 1942 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1943 | |
f963735a | 1944 | for_each_active_policy(policy) { |
49f18560 | 1945 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1946 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1947 | policy); | |
ba41e1bc | 1948 | } else if (has_target()) { |
49f18560 | 1949 | down_write(&policy->rwsem); |
0a300767 | 1950 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1951 | up_write(&policy->rwsem); |
1952 | ||
1953 | if (ret) | |
1954 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1955 | __func__, policy); | |
1956 | } | |
2f0aea93 VK |
1957 | } |
1958 | } | |
1da177e4 | 1959 | |
a62f68f5 RW |
1960 | /** |
1961 | * cpufreq_driver_test_flags - Test cpufreq driver's flags against given ones. | |
1962 | * @flags: Flags to test against the current cpufreq driver's flags. | |
1963 | * | |
1964 | * Assumes that the driver is there, so callers must ensure that this is the | |
1965 | * case. | |
1966 | */ | |
1967 | bool cpufreq_driver_test_flags(u16 flags) | |
1968 | { | |
1969 | return !!(cpufreq_driver->flags & flags); | |
1970 | } | |
1971 | ||
9d95046e | 1972 | /** |
ec06e586 | 1973 | * cpufreq_get_current_driver - Return the current driver's name. |
9d95046e | 1974 | * |
ec06e586 RW |
1975 | * Return the name string of the currently registered cpufreq driver or NULL if |
1976 | * none. | |
9d95046e BP |
1977 | */ |
1978 | const char *cpufreq_get_current_driver(void) | |
1979 | { | |
1c3d85dd RW |
1980 | if (cpufreq_driver) |
1981 | return cpufreq_driver->name; | |
1982 | ||
1983 | return NULL; | |
9d95046e BP |
1984 | } |
1985 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1986 | |
51315cdf | 1987 | /** |
ec06e586 | 1988 | * cpufreq_get_driver_data - Return current driver data. |
51315cdf | 1989 | * |
ec06e586 RW |
1990 | * Return the private data of the currently registered cpufreq driver, or NULL |
1991 | * if no cpufreq driver has been registered. | |
51315cdf TP |
1992 | */ |
1993 | void *cpufreq_get_driver_data(void) | |
1994 | { | |
1995 | if (cpufreq_driver) | |
1996 | return cpufreq_driver->driver_data; | |
1997 | ||
1998 | return NULL; | |
1999 | } | |
2000 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
2001 | ||
1da177e4 LT |
2002 | /********************************************************************* |
2003 | * NOTIFIER LISTS INTERFACE * | |
2004 | *********************************************************************/ | |
2005 | ||
2006 | /** | |
ec06e586 RW |
2007 | * cpufreq_register_notifier - Register a notifier with cpufreq. |
2008 | * @nb: notifier function to register. | |
2009 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 2010 | * |
ec06e586 RW |
2011 | * Add a notifier to one of two lists: either a list of notifiers that run on |
2012 | * clock rate changes (once before and once after every transition), or a list | |
2013 | * of notifiers that ron on cpufreq policy changes. | |
1da177e4 | 2014 | * |
ec06e586 RW |
2015 | * This function may sleep and it has the same return values as |
2016 | * blocking_notifier_chain_register(). | |
1da177e4 LT |
2017 | */ |
2018 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
2019 | { | |
2020 | int ret; | |
2021 | ||
d5aaffa9 DB |
2022 | if (cpufreq_disabled()) |
2023 | return -EINVAL; | |
2024 | ||
1da177e4 LT |
2025 | switch (list) { |
2026 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
2027 | mutex_lock(&cpufreq_fast_switch_lock); |
2028 | ||
2029 | if (cpufreq_fast_switch_count > 0) { | |
2030 | mutex_unlock(&cpufreq_fast_switch_lock); | |
2031 | return -EBUSY; | |
2032 | } | |
b4dfdbb3 | 2033 | ret = srcu_notifier_chain_register( |
e041c683 | 2034 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2035 | if (!ret) |
2036 | cpufreq_fast_switch_count--; | |
2037 | ||
2038 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2039 | break; |
2040 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2041 | ret = blocking_notifier_chain_register( |
2042 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2043 | break; |
2044 | default: | |
2045 | ret = -EINVAL; | |
2046 | } | |
1da177e4 LT |
2047 | |
2048 | return ret; | |
2049 | } | |
2050 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
2051 | ||
1da177e4 | 2052 | /** |
ec06e586 RW |
2053 | * cpufreq_unregister_notifier - Unregister a notifier from cpufreq. |
2054 | * @nb: notifier block to be unregistered. | |
2055 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 2056 | * |
ec06e586 | 2057 | * Remove a notifier from one of the cpufreq notifier lists. |
1da177e4 | 2058 | * |
ec06e586 RW |
2059 | * This function may sleep and it has the same return values as |
2060 | * blocking_notifier_chain_unregister(). | |
1da177e4 LT |
2061 | */ |
2062 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
2063 | { | |
2064 | int ret; | |
2065 | ||
d5aaffa9 DB |
2066 | if (cpufreq_disabled()) |
2067 | return -EINVAL; | |
2068 | ||
1da177e4 LT |
2069 | switch (list) { |
2070 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
2071 | mutex_lock(&cpufreq_fast_switch_lock); |
2072 | ||
b4dfdbb3 | 2073 | ret = srcu_notifier_chain_unregister( |
e041c683 | 2074 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2075 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
2076 | cpufreq_fast_switch_count++; | |
2077 | ||
2078 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2079 | break; |
2080 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2081 | ret = blocking_notifier_chain_unregister( |
2082 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2083 | break; |
2084 | default: | |
2085 | ret = -EINVAL; | |
2086 | } | |
1da177e4 LT |
2087 | |
2088 | return ret; | |
2089 | } | |
2090 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
2091 | ||
2092 | ||
2093 | /********************************************************************* | |
2094 | * GOVERNORS * | |
2095 | *********************************************************************/ | |
2096 | ||
b7898fda RW |
2097 | /** |
2098 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
2099 | * @policy: cpufreq policy to switch the frequency for. | |
2100 | * @target_freq: New frequency to set (may be approximate). | |
2101 | * | |
2102 | * Carry out a fast frequency switch without sleeping. | |
2103 | * | |
2104 | * The driver's ->fast_switch() callback invoked by this function must be | |
2105 | * suitable for being called from within RCU-sched read-side critical sections | |
2106 | * and it is expected to select the minimum available frequency greater than or | |
2107 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2108 | * | |
2109 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2110 | * | |
2111 | * Governors calling this function must guarantee that it will never be invoked | |
2112 | * twice in parallel for the same policy and that it will never be called in | |
2113 | * parallel with either ->target() or ->target_index() for the same policy. | |
2114 | * | |
209887e6 VK |
2115 | * Returns the actual frequency set for the CPU. |
2116 | * | |
2117 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2118 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2119 | */ |
2120 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2121 | unsigned int target_freq) | |
2122 | { | |
1a0419b0 | 2123 | unsigned int freq; |
08d8c65e | 2124 | int cpu; |
1a0419b0 | 2125 | |
b9af6948 | 2126 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
1a0419b0 IV |
2127 | freq = cpufreq_driver->fast_switch(policy, target_freq); |
2128 | ||
96f60cdd VK |
2129 | if (!freq) |
2130 | return 0; | |
2131 | ||
08d8c65e | 2132 | policy->cur = freq; |
1a0419b0 IV |
2133 | arch_set_freq_scale(policy->related_cpus, freq, |
2134 | policy->cpuinfo.max_freq); | |
96f60cdd | 2135 | cpufreq_stats_record_transition(policy, freq); |
b7898fda | 2136 | |
08d8c65e VK |
2137 | if (trace_cpu_frequency_enabled()) { |
2138 | for_each_cpu(cpu, policy->cpus) | |
2139 | trace_cpu_frequency(freq, cpu); | |
2140 | } | |
2141 | ||
1a0419b0 | 2142 | return freq; |
b7898fda RW |
2143 | } |
2144 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2145 | ||
ee2cc427 RW |
2146 | /** |
2147 | * cpufreq_driver_adjust_perf - Adjust CPU performance level in one go. | |
2148 | * @cpu: Target CPU. | |
2149 | * @min_perf: Minimum (required) performance level (units of @capacity). | |
4e6df217 | 2150 | * @target_perf: Target (desired) performance level (units of @capacity). |
ee2cc427 RW |
2151 | * @capacity: Capacity of the target CPU. |
2152 | * | |
2153 | * Carry out a fast performance level switch of @cpu without sleeping. | |
2154 | * | |
2155 | * The driver's ->adjust_perf() callback invoked by this function must be | |
2156 | * suitable for being called from within RCU-sched read-side critical sections | |
2157 | * and it is expected to select a suitable performance level equal to or above | |
2158 | * @min_perf and preferably equal to or below @target_perf. | |
2159 | * | |
2160 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2161 | * | |
2162 | * Governors calling this function must guarantee that it will never be invoked | |
2163 | * twice in parallel for the same CPU and that it will never be called in | |
2164 | * parallel with either ->target() or ->target_index() or ->fast_switch() for | |
2165 | * the same CPU. | |
2166 | */ | |
2167 | void cpufreq_driver_adjust_perf(unsigned int cpu, | |
2168 | unsigned long min_perf, | |
2169 | unsigned long target_perf, | |
2170 | unsigned long capacity) | |
2171 | { | |
2172 | cpufreq_driver->adjust_perf(cpu, min_perf, target_perf, capacity); | |
2173 | } | |
2174 | ||
2175 | /** | |
2176 | * cpufreq_driver_has_adjust_perf - Check "direct fast switch" callback. | |
2177 | * | |
2178 | * Return 'true' if the ->adjust_perf callback is present for the | |
2179 | * current driver or 'false' otherwise. | |
2180 | */ | |
2181 | bool cpufreq_driver_has_adjust_perf(void) | |
2182 | { | |
2183 | return !!cpufreq_driver->adjust_perf; | |
2184 | } | |
2185 | ||
1c03a2d0 VK |
2186 | /* Must set freqs->new to intermediate frequency */ |
2187 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2188 | struct cpufreq_freqs *freqs, int index) | |
2189 | { | |
2190 | int ret; | |
2191 | ||
2192 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2193 | ||
2194 | /* We don't need to switch to intermediate freq */ | |
2195 | if (!freqs->new) | |
2196 | return 0; | |
2197 | ||
2198 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2199 | __func__, policy->cpu, freqs->old, freqs->new); | |
2200 | ||
2201 | cpufreq_freq_transition_begin(policy, freqs); | |
2202 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2203 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2204 | ||
2205 | if (ret) | |
2206 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2207 | __func__, ret); | |
2208 | ||
2209 | return ret; | |
2210 | } | |
2211 | ||
23727845 | 2212 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2213 | { |
1c03a2d0 | 2214 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
56a7ff75 | 2215 | unsigned int restore_freq, intermediate_freq = 0; |
23727845 | 2216 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2217 | int retval = -EINVAL; |
2218 | bool notify; | |
2219 | ||
23727845 VK |
2220 | if (newfreq == policy->cur) |
2221 | return 0; | |
2222 | ||
56a7ff75 RW |
2223 | /* Save last value to restore later on errors */ |
2224 | restore_freq = policy->cur; | |
2225 | ||
8d65775d | 2226 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2227 | if (notify) { |
1c03a2d0 VK |
2228 | /* Handle switching to intermediate frequency */ |
2229 | if (cpufreq_driver->get_intermediate) { | |
2230 | retval = __target_intermediate(policy, &freqs, index); | |
2231 | if (retval) | |
2232 | return retval; | |
2233 | ||
2234 | intermediate_freq = freqs.new; | |
2235 | /* Set old freq to intermediate */ | |
2236 | if (intermediate_freq) | |
2237 | freqs.old = freqs.new; | |
2238 | } | |
8d65775d | 2239 | |
23727845 | 2240 | freqs.new = newfreq; |
8d65775d VK |
2241 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2242 | __func__, policy->cpu, freqs.old, freqs.new); | |
2243 | ||
2244 | cpufreq_freq_transition_begin(policy, &freqs); | |
2245 | } | |
2246 | ||
2247 | retval = cpufreq_driver->target_index(policy, index); | |
2248 | if (retval) | |
2249 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2250 | retval); | |
2251 | ||
1c03a2d0 | 2252 | if (notify) { |
8d65775d VK |
2253 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2254 | ||
1c03a2d0 VK |
2255 | /* |
2256 | * Failed after setting to intermediate freq? Driver should have | |
2257 | * reverted back to initial frequency and so should we. Check | |
2258 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2259 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2260 | */ |
2261 | if (unlikely(retval && intermediate_freq)) { | |
2262 | freqs.old = intermediate_freq; | |
56a7ff75 | 2263 | freqs.new = restore_freq; |
1c03a2d0 VK |
2264 | cpufreq_freq_transition_begin(policy, &freqs); |
2265 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2266 | } | |
2267 | } | |
2268 | ||
8d65775d VK |
2269 | return retval; |
2270 | } | |
2271 | ||
1da177e4 LT |
2272 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2273 | unsigned int target_freq, | |
2274 | unsigned int relation) | |
2275 | { | |
7249924e | 2276 | unsigned int old_target_freq = target_freq; |
c32b6b8e | 2277 | |
a7b422cd KRW |
2278 | if (cpufreq_disabled()) |
2279 | return -ENODEV; | |
2280 | ||
f9ccdec2 | 2281 | target_freq = __resolve_freq(policy, target_freq, relation); |
7249924e VK |
2282 | |
2283 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2284 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2285 | |
9c0ebcf7 VK |
2286 | /* |
2287 | * This might look like a redundant call as we are checking it again | |
2288 | * after finding index. But it is left intentionally for cases where | |
2289 | * exactly same freq is called again and so we can save on few function | |
2290 | * calls. | |
2291 | */ | |
1c534352 RW |
2292 | if (target_freq == policy->cur && |
2293 | !(cpufreq_driver->flags & CPUFREQ_NEED_UPDATE_LIMITS)) | |
5a1c0228 VK |
2294 | return 0; |
2295 | ||
1f39fa0d VD |
2296 | if (cpufreq_driver->target) { |
2297 | /* | |
2298 | * If the driver hasn't setup a single inefficient frequency, | |
2299 | * it's unlikely it knows how to decode CPUFREQ_RELATION_E. | |
2300 | */ | |
2301 | if (!policy->efficiencies_available) | |
2302 | relation &= ~CPUFREQ_RELATION_E; | |
2303 | ||
6019d23a | 2304 | return cpufreq_driver->target(policy, target_freq, relation); |
1f39fa0d | 2305 | } |
9c0ebcf7 | 2306 | |
6019d23a RW |
2307 | if (!cpufreq_driver->target_index) |
2308 | return -EINVAL; | |
9c0ebcf7 | 2309 | |
f9ccdec2 | 2310 | return __target_index(policy, policy->cached_resolved_idx); |
1da177e4 LT |
2311 | } |
2312 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2313 | ||
1da177e4 LT |
2314 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2315 | unsigned int target_freq, | |
2316 | unsigned int relation) | |
2317 | { | |
62c23a89 | 2318 | int ret; |
1da177e4 | 2319 | |
ad7722da | 2320 | down_write(&policy->rwsem); |
1da177e4 LT |
2321 | |
2322 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2323 | ||
ad7722da | 2324 | up_write(&policy->rwsem); |
1da177e4 | 2325 | |
1da177e4 LT |
2326 | return ret; |
2327 | } | |
2328 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2329 | ||
de1df26b RW |
2330 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2331 | { | |
2332 | return NULL; | |
2333 | } | |
2334 | ||
a92604b4 | 2335 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2336 | { |
cc993cab | 2337 | int ret; |
6afde10c | 2338 | |
2f0aea93 VK |
2339 | /* Don't start any governor operations if we are entering suspend */ |
2340 | if (cpufreq_suspended) | |
2341 | return 0; | |
cb57720b EZ |
2342 | /* |
2343 | * Governor might not be initiated here if ACPI _PPC changed | |
2344 | * notification happened, so check it. | |
2345 | */ | |
2346 | if (!policy->governor) | |
2347 | return -EINVAL; | |
2f0aea93 | 2348 | |
ed4676e2 | 2349 | /* Platform doesn't want dynamic frequency switching ? */ |
9a2a9ebc | 2350 | if (policy->governor->flags & CPUFREQ_GOV_DYNAMIC_SWITCHING && |
fc4c709f | 2351 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2352 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2353 | ||
2354 | if (gov) { | |
fe829ed8 | 2355 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2356 | policy->governor->name, gov->name); |
6afde10c | 2357 | policy->governor = gov; |
de1df26b RW |
2358 | } else { |
2359 | return -EINVAL; | |
6afde10c | 2360 | } |
1c256245 | 2361 | } |
1da177e4 | 2362 | |
a92604b4 RW |
2363 | if (!try_module_get(policy->governor->owner)) |
2364 | return -EINVAL; | |
95731ebb | 2365 | |
a92604b4 | 2366 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2367 | |
e788892b RW |
2368 | if (policy->governor->init) { |
2369 | ret = policy->governor->init(policy); | |
2370 | if (ret) { | |
36be3418 | 2371 | module_put(policy->governor->owner); |
e788892b RW |
2372 | return ret; |
2373 | } | |
36be3418 | 2374 | } |
1da177e4 | 2375 | |
ea9364bb RW |
2376 | policy->strict_target = !!(policy->governor->flags & CPUFREQ_GOV_STRICT_TARGET); |
2377 | ||
a92604b4 RW |
2378 | return 0; |
2379 | } | |
2380 | ||
2381 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2382 | { | |
2383 | if (cpufreq_suspended || !policy->governor) | |
2384 | return; | |
2385 | ||
2386 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2387 | ||
e788892b RW |
2388 | if (policy->governor->exit) |
2389 | policy->governor->exit(policy); | |
a92604b4 | 2390 | |
a92604b4 | 2391 | module_put(policy->governor->owner); |
1da177e4 LT |
2392 | } |
2393 | ||
f6ebbcf0 | 2394 | int cpufreq_start_governor(struct cpufreq_policy *policy) |
0a300767 RW |
2395 | { |
2396 | int ret; | |
2397 | ||
a92604b4 RW |
2398 | if (cpufreq_suspended) |
2399 | return 0; | |
2400 | ||
2401 | if (!policy->governor) | |
2402 | return -EINVAL; | |
2403 | ||
2404 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2405 | ||
407d0fff | 2406 | if (cpufreq_driver->get) |
5980752e | 2407 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2408 | |
e788892b RW |
2409 | if (policy->governor->start) { |
2410 | ret = policy->governor->start(policy); | |
2411 | if (ret) | |
2412 | return ret; | |
2413 | } | |
2414 | ||
2415 | if (policy->governor->limits) | |
2416 | policy->governor->limits(policy); | |
d6ff44d6 | 2417 | |
d6ff44d6 | 2418 | return 0; |
0a300767 RW |
2419 | } |
2420 | ||
f6ebbcf0 | 2421 | void cpufreq_stop_governor(struct cpufreq_policy *policy) |
a92604b4 RW |
2422 | { |
2423 | if (cpufreq_suspended || !policy->governor) | |
2424 | return; | |
2425 | ||
2426 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2427 | ||
e788892b RW |
2428 | if (policy->governor->stop) |
2429 | policy->governor->stop(policy); | |
a92604b4 RW |
2430 | } |
2431 | ||
2432 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2433 | { | |
2434 | if (cpufreq_suspended || !policy->governor) | |
2435 | return; | |
2436 | ||
2437 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2438 | ||
e788892b RW |
2439 | if (policy->governor->limits) |
2440 | policy->governor->limits(policy); | |
0a300767 RW |
2441 | } |
2442 | ||
1da177e4 LT |
2443 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2444 | { | |
3bcb09a3 | 2445 | int err; |
1da177e4 LT |
2446 | |
2447 | if (!governor) | |
2448 | return -EINVAL; | |
2449 | ||
a7b422cd KRW |
2450 | if (cpufreq_disabled()) |
2451 | return -ENODEV; | |
2452 | ||
3fc54d37 | 2453 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2454 | |
3bcb09a3 | 2455 | err = -EBUSY; |
42f91fa1 | 2456 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2457 | err = 0; |
2458 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2459 | } |
1da177e4 | 2460 | |
32ee8c3e | 2461 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2462 | return err; |
1da177e4 LT |
2463 | } |
2464 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2465 | ||
1da177e4 LT |
2466 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2467 | { | |
4573237b VK |
2468 | struct cpufreq_policy *policy; |
2469 | unsigned long flags; | |
90e41bac | 2470 | |
1da177e4 LT |
2471 | if (!governor) |
2472 | return; | |
2473 | ||
a7b422cd KRW |
2474 | if (cpufreq_disabled()) |
2475 | return; | |
2476 | ||
4573237b VK |
2477 | /* clear last_governor for all inactive policies */ |
2478 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2479 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2480 | if (!strcmp(policy->last_governor, governor->name)) { |
2481 | policy->governor = NULL; | |
4573237b | 2482 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2483 | } |
90e41bac | 2484 | } |
4573237b | 2485 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2486 | |
3fc54d37 | 2487 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2488 | list_del(&governor->governor_list); |
3fc54d37 | 2489 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2490 | } |
2491 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2492 | ||
2493 | ||
1da177e4 LT |
2494 | /********************************************************************* |
2495 | * POLICY INTERFACE * | |
2496 | *********************************************************************/ | |
2497 | ||
2498 | /** | |
2499 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2500 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2501 | * is written | |
a9909c21 | 2502 | * @cpu: CPU to find the policy for |
1da177e4 LT |
2503 | * |
2504 | * Reads the current cpufreq policy. | |
2505 | */ | |
2506 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2507 | { | |
2508 | struct cpufreq_policy *cpu_policy; | |
2509 | if (!policy) | |
2510 | return -EINVAL; | |
2511 | ||
2512 | cpu_policy = cpufreq_cpu_get(cpu); | |
2513 | if (!cpu_policy) | |
2514 | return -EINVAL; | |
2515 | ||
d5b73cd8 | 2516 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2517 | |
2518 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2519 | return 0; |
2520 | } | |
2521 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2522 | ||
a0dbb819 RW |
2523 | /** |
2524 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2525 | * @policy: Policy object to modify. | |
1e4f63ae RW |
2526 | * @new_gov: Policy governor pointer. |
2527 | * @new_pol: Policy value (for drivers with built-in governors). | |
a0dbb819 | 2528 | * |
1e4f63ae RW |
2529 | * Invoke the cpufreq driver's ->verify() callback to sanity-check the frequency |
2530 | * limits to be set for the policy, update @policy with the verified limits | |
2531 | * values and either invoke the driver's ->setpolicy() callback (if present) or | |
2532 | * carry out a governor update for @policy. That is, run the current governor's | |
2533 | * ->limits() callback (if @new_gov points to the same object as the one in | |
2534 | * @policy) or replace the governor for @policy with @new_gov. | |
a0dbb819 RW |
2535 | * |
2536 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2537 | */ |
1e4f63ae RW |
2538 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
2539 | struct cpufreq_governor *new_gov, | |
2540 | unsigned int new_pol) | |
1da177e4 | 2541 | { |
1e4f63ae | 2542 | struct cpufreq_policy_data new_data; |
d9a789c7 RW |
2543 | struct cpufreq_governor *old_gov; |
2544 | int ret; | |
1da177e4 | 2545 | |
1e4f63ae RW |
2546 | memcpy(&new_data.cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
2547 | new_data.freq_table = policy->freq_table; | |
2548 | new_data.cpu = policy->cpu; | |
fba9573b | 2549 | /* |
67d874c3 VK |
2550 | * PM QoS framework collects all the requests from users and provide us |
2551 | * the final aggregated value here. | |
2552 | */ | |
1e4f63ae RW |
2553 | new_data.min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); |
2554 | new_data.max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); | |
2555 | ||
2556 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", | |
2557 | new_data.cpu, new_data.min, new_data.max); | |
9c9a43ed | 2558 | |
737ffb27 VK |
2559 | /* |
2560 | * Verify that the CPU speed can be set within these limits and make sure | |
2561 | * that min <= max. | |
2562 | */ | |
1e4f63ae | 2563 | ret = cpufreq_driver->verify(&new_data); |
1da177e4 | 2564 | if (ret) |
d9a789c7 | 2565 | return ret; |
1da177e4 | 2566 | |
15171769 VD |
2567 | /* |
2568 | * Resolve policy min/max to available frequencies. It ensures | |
2569 | * no frequency resolution will neither overshoot the requested maximum | |
2570 | * nor undershoot the requested minimum. | |
2571 | */ | |
1e4f63ae RW |
2572 | policy->min = new_data.min; |
2573 | policy->max = new_data.max; | |
15171769 VD |
2574 | policy->min = __resolve_freq(policy, policy->min, CPUFREQ_RELATION_L); |
2575 | policy->max = __resolve_freq(policy, policy->max, CPUFREQ_RELATION_H); | |
601b2185 | 2576 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2577 | |
e3c06236 SM |
2578 | policy->cached_target_freq = UINT_MAX; |
2579 | ||
2d06d8c4 | 2580 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2581 | policy->min, policy->max); |
1da177e4 | 2582 | |
1c3d85dd | 2583 | if (cpufreq_driver->setpolicy) { |
1e4f63ae | 2584 | policy->policy = new_pol; |
2d06d8c4 | 2585 | pr_debug("setting range\n"); |
167a38dc | 2586 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2587 | } |
1da177e4 | 2588 | |
1e4f63ae | 2589 | if (new_gov == policy->governor) { |
2bb4059e | 2590 | pr_debug("governor limits update\n"); |
a92604b4 | 2591 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2592 | return 0; |
0a300767 | 2593 | } |
7bd353a9 | 2594 | |
d9a789c7 RW |
2595 | pr_debug("governor switch\n"); |
2596 | ||
2597 | /* save old, working values */ | |
2598 | old_gov = policy->governor; | |
2599 | /* end old governor */ | |
2600 | if (old_gov) { | |
45482c70 | 2601 | cpufreq_stop_governor(policy); |
36be3418 | 2602 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2603 | } |
2604 | ||
d9a789c7 | 2605 | /* start new governor */ |
1e4f63ae | 2606 | policy->governor = new_gov; |
a92604b4 | 2607 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2608 | if (!ret) { |
0a300767 RW |
2609 | ret = cpufreq_start_governor(policy); |
2610 | if (!ret) { | |
2bb4059e | 2611 | pr_debug("governor change\n"); |
531b5c9f | 2612 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2613 | return 0; |
2614 | } | |
b7898fda | 2615 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2616 | } |
2617 | ||
2618 | /* new governor failed, so re-start old one */ | |
2619 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2620 | if (old_gov) { | |
2621 | policy->governor = old_gov; | |
a92604b4 | 2622 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2623 | policy->governor = NULL; |
2624 | else | |
0a300767 | 2625 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2626 | } |
2627 | ||
4bc384ae | 2628 | return ret; |
1da177e4 LT |
2629 | } |
2630 | ||
1da177e4 | 2631 | /** |
a0dbb819 RW |
2632 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2633 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2634 | * |
a0dbb819 | 2635 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2636 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2637 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2638 | * for the policy in question, among other things. | |
1da177e4 | 2639 | */ |
30248fef | 2640 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2641 | { |
540a3758 | 2642 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2643 | |
fefa8ff8 | 2644 | if (!policy) |
30248fef | 2645 | return; |
1da177e4 | 2646 | |
bb176f7d VK |
2647 | /* |
2648 | * BIOS might change freq behind our back | |
2649 | * -> ask driver for current freq and notify governors about a change | |
2650 | */ | |
5ddc6d4e | 2651 | if (cpufreq_driver->get && has_target() && |
5980752e | 2652 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2653 | goto unlock; |
30248fef | 2654 | |
70a59fde | 2655 | refresh_frequency_limits(policy); |
1da177e4 | 2656 | |
fefa8ff8 | 2657 | unlock: |
540a3758 | 2658 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2659 | } |
2660 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2661 | ||
5a25e3f7 RW |
2662 | /** |
2663 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2664 | * @cpu: CPU to update the policy limits for. | |
2665 | * | |
2666 | * Invoke the driver's ->update_limits callback if present or call | |
2667 | * cpufreq_update_policy() for @cpu. | |
2668 | */ | |
2669 | void cpufreq_update_limits(unsigned int cpu) | |
2670 | { | |
2671 | if (cpufreq_driver->update_limits) | |
2672 | cpufreq_driver->update_limits(cpu); | |
2673 | else | |
2674 | cpufreq_update_policy(cpu); | |
2675 | } | |
2676 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2677 | ||
6f19efc0 LM |
2678 | /********************************************************************* |
2679 | * BOOST * | |
2680 | *********************************************************************/ | |
cf6fada7 | 2681 | static int cpufreq_boost_set_sw(struct cpufreq_policy *policy, int state) |
6f19efc0 | 2682 | { |
cf6fada7 | 2683 | int ret; |
49f18560 | 2684 | |
cf6fada7 XW |
2685 | if (!policy->freq_table) |
2686 | return -ENXIO; | |
f8bfc116 | 2687 | |
cf6fada7 XW |
2688 | ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table); |
2689 | if (ret) { | |
2690 | pr_err("%s: Policy frequency update failed\n", __func__); | |
2691 | return ret; | |
6f19efc0 LM |
2692 | } |
2693 | ||
cf6fada7 XW |
2694 | ret = freq_qos_update_request(policy->max_freq_req, policy->max); |
2695 | if (ret < 0) | |
2696 | return ret; | |
2697 | ||
552abb88 | 2698 | return 0; |
6f19efc0 LM |
2699 | } |
2700 | ||
2701 | int cpufreq_boost_trigger_state(int state) | |
2702 | { | |
cf6fada7 | 2703 | struct cpufreq_policy *policy; |
6f19efc0 LM |
2704 | unsigned long flags; |
2705 | int ret = 0; | |
2706 | ||
2707 | if (cpufreq_driver->boost_enabled == state) | |
2708 | return 0; | |
2709 | ||
2710 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2711 | cpufreq_driver->boost_enabled = state; | |
2712 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2713 | ||
09681a07 | 2714 | cpus_read_lock(); |
cf6fada7 XW |
2715 | for_each_active_policy(policy) { |
2716 | ret = cpufreq_driver->set_boost(policy, state); | |
2717 | if (ret) | |
2718 | goto err_reset_state; | |
6f19efc0 | 2719 | } |
09681a07 | 2720 | cpus_read_unlock(); |
cf6fada7 XW |
2721 | |
2722 | return 0; | |
2723 | ||
2724 | err_reset_state: | |
09681a07 | 2725 | cpus_read_unlock(); |
cf6fada7 XW |
2726 | |
2727 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2728 | cpufreq_driver->boost_enabled = !state; | |
2729 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2730 | ||
2731 | pr_err("%s: Cannot %s BOOST\n", | |
2732 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2733 | |
2734 | return ret; | |
2735 | } | |
2736 | ||
41669da0 | 2737 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2738 | { |
89f98d7e | 2739 | return cpufreq_driver->set_boost; |
6f19efc0 | 2740 | } |
6f19efc0 | 2741 | |
44139ed4 VK |
2742 | static int create_boost_sysfs_file(void) |
2743 | { | |
2744 | int ret; | |
2745 | ||
c82bd444 | 2746 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2747 | if (ret) |
2748 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2749 | __func__); | |
2750 | ||
2751 | return ret; | |
2752 | } | |
2753 | ||
2754 | static void remove_boost_sysfs_file(void) | |
2755 | { | |
2756 | if (cpufreq_boost_supported()) | |
c82bd444 | 2757 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2758 | } |
2759 | ||
2760 | int cpufreq_enable_boost_support(void) | |
2761 | { | |
2762 | if (!cpufreq_driver) | |
2763 | return -EINVAL; | |
2764 | ||
2765 | if (cpufreq_boost_supported()) | |
2766 | return 0; | |
2767 | ||
7a6c79f2 | 2768 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2769 | |
2770 | /* This will get removed on driver unregister */ | |
2771 | return create_boost_sysfs_file(); | |
2772 | } | |
2773 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2774 | ||
6f19efc0 LM |
2775 | int cpufreq_boost_enabled(void) |
2776 | { | |
2777 | return cpufreq_driver->boost_enabled; | |
2778 | } | |
2779 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2780 | ||
1da177e4 LT |
2781 | /********************************************************************* |
2782 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2783 | *********************************************************************/ | |
27622b06 | 2784 | static enum cpuhp_state hp_online; |
1da177e4 | 2785 | |
c4a3fa26 CY |
2786 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2787 | { | |
2788 | cpufreq_online(cpu); | |
2789 | ||
2790 | return 0; | |
2791 | } | |
2792 | ||
2793 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2794 | { | |
2795 | cpufreq_offline(cpu); | |
2796 | ||
2797 | return 0; | |
2798 | } | |
2799 | ||
1da177e4 LT |
2800 | /** |
2801 | * cpufreq_register_driver - register a CPU Frequency driver | |
2802 | * @driver_data: A struct cpufreq_driver containing the values# | |
2803 | * submitted by the CPU Frequency driver. | |
2804 | * | |
bb176f7d | 2805 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2806 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2807 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2808 | * |
2809 | */ | |
221dee28 | 2810 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2811 | { |
2812 | unsigned long flags; | |
2813 | int ret; | |
2814 | ||
a7b422cd KRW |
2815 | if (cpufreq_disabled()) |
2816 | return -ENODEV; | |
2817 | ||
46770be0 VK |
2818 | /* |
2819 | * The cpufreq core depends heavily on the availability of device | |
2820 | * structure, make sure they are available before proceeding further. | |
2821 | */ | |
2822 | if (!get_cpu_device(0)) | |
2823 | return -EPROBE_DEFER; | |
2824 | ||
1da177e4 | 2825 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2826 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2827 | driver_data->target) || |
2828 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2829 | driver_data->target)) || |
a9a22b57 | 2830 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2831 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2832 | return -EINVAL; |
2833 | ||
2d06d8c4 | 2834 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2835 | |
fdd320da | 2836 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2837 | cpus_read_lock(); |
fdd320da | 2838 | |
0d1857a1 | 2839 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2840 | if (cpufreq_driver) { |
0d1857a1 | 2841 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2842 | ret = -EEXIST; |
2843 | goto out; | |
1da177e4 | 2844 | } |
1c3d85dd | 2845 | cpufreq_driver = driver_data; |
0d1857a1 | 2846 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2847 | |
874f6353 IV |
2848 | /* |
2849 | * Mark support for the scheduler's frequency invariance engine for | |
2850 | * drivers that implement target(), target_index() or fast_switch(). | |
2851 | */ | |
2852 | if (!cpufreq_driver->setpolicy) { | |
2853 | static_branch_enable_cpuslocked(&cpufreq_freq_invariance); | |
2854 | pr_debug("supports frequency invariance"); | |
2855 | } | |
2856 | ||
bc68b7df VK |
2857 | if (driver_data->setpolicy) |
2858 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2859 | ||
7a6c79f2 RW |
2860 | if (cpufreq_boost_supported()) { |
2861 | ret = create_boost_sysfs_file(); | |
2862 | if (ret) | |
2863 | goto err_null_driver; | |
2864 | } | |
6f19efc0 | 2865 | |
8a25a2fd | 2866 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2867 | if (ret) |
6f19efc0 | 2868 | goto err_boost_unreg; |
1da177e4 | 2869 | |
5ae4a4b4 | 2870 | if (unlikely(list_empty(&cpufreq_policy_list))) { |
1da177e4 | 2871 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2872 | ret = -ENODEV; |
ce1bcfe9 VK |
2873 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2874 | driver_data->name); | |
2875 | goto err_if_unreg; | |
1da177e4 LT |
2876 | } |
2877 | ||
a92551e4 SAS |
2878 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2879 | "cpufreq:online", | |
2880 | cpuhp_cpufreq_online, | |
2881 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2882 | if (ret < 0) |
2883 | goto err_if_unreg; | |
2884 | hp_online = ret; | |
5372e054 | 2885 | ret = 0; |
27622b06 | 2886 | |
2d06d8c4 | 2887 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2888 | goto out; |
fdd320da | 2889 | |
8a25a2fd KS |
2890 | err_if_unreg: |
2891 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2892 | err_boost_unreg: |
44139ed4 | 2893 | remove_boost_sysfs_file(); |
8f5bc2ab | 2894 | err_null_driver: |
0d1857a1 | 2895 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2896 | cpufreq_driver = NULL; |
0d1857a1 | 2897 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2898 | out: |
a92551e4 | 2899 | cpus_read_unlock(); |
3834abb4 | 2900 | return ret; |
1da177e4 LT |
2901 | } |
2902 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2903 | ||
a9909c21 | 2904 | /* |
1da177e4 LT |
2905 | * cpufreq_unregister_driver - unregister the current CPUFreq driver |
2906 | * | |
bb176f7d | 2907 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2908 | * the right to do so, i.e. if you have succeeded in initialising before! |
2909 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2910 | * currently not initialised. | |
2911 | */ | |
dd329e1e | 2912 | void cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2913 | { |
2914 | unsigned long flags; | |
2915 | ||
dd329e1e UKK |
2916 | if (WARN_ON(!cpufreq_driver || (driver != cpufreq_driver))) |
2917 | return; | |
1da177e4 | 2918 | |
2d06d8c4 | 2919 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2920 | |
454d3a25 | 2921 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2922 | cpus_read_lock(); |
8a25a2fd | 2923 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2924 | remove_boost_sysfs_file(); |
874f6353 | 2925 | static_branch_disable_cpuslocked(&cpufreq_freq_invariance); |
a92551e4 | 2926 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2927 | |
0d1857a1 | 2928 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2929 | |
1c3d85dd | 2930 | cpufreq_driver = NULL; |
6eed9404 | 2931 | |
0d1857a1 | 2932 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2933 | cpus_read_unlock(); |
1da177e4 LT |
2934 | } |
2935 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2936 | |
2937 | static int __init cpufreq_core_init(void) | |
2938 | { | |
8412b456 | 2939 | struct cpufreq_governor *gov = cpufreq_default_governor(); |
2744a63c | 2940 | struct device *dev_root; |
8412b456 | 2941 | |
a7b422cd KRW |
2942 | if (cpufreq_disabled()) |
2943 | return -ENODEV; | |
2944 | ||
2744a63c GKH |
2945 | dev_root = bus_get_dev_root(&cpu_subsys); |
2946 | if (dev_root) { | |
2947 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &dev_root->kobj); | |
2948 | put_device(dev_root); | |
2949 | } | |
8aa84ad8 TR |
2950 | BUG_ON(!cpufreq_global_kobject); |
2951 | ||
8412b456 QP |
2952 | if (!strlen(default_governor)) |
2953 | strncpy(default_governor, gov->name, CPUFREQ_NAME_LEN); | |
2954 | ||
5a01f2e8 VP |
2955 | return 0; |
2956 | } | |
d82f2692 | 2957 | module_param(off, int, 0444); |
8412b456 | 2958 | module_param_string(default_governor, default_governor, CPUFREQ_NAME_LEN, 0444); |
5a01f2e8 | 2959 | core_initcall(cpufreq_core_init); |