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> |
6f4f2723 TR |
31 | #include <trace/events/power.h> |
32 | ||
b4f0676f | 33 | static LIST_HEAD(cpufreq_policy_list); |
f963735a | 34 | |
f963735a | 35 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
36 | #define for_each_suitable_policy(__policy, __active) \ |
37 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
38 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
39 | |
40 | #define for_each_active_policy(__policy) \ | |
41 | for_each_suitable_policy(__policy, true) | |
42 | #define for_each_inactive_policy(__policy) \ | |
43 | for_each_suitable_policy(__policy, false) | |
44 | ||
45 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
46 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
47 | ||
f7b27061 VK |
48 | /* Iterate over governors */ |
49 | static LIST_HEAD(cpufreq_governor_list); | |
50 | #define for_each_governor(__governor) \ | |
51 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
52 | ||
8412b456 QP |
53 | static char default_governor[CPUFREQ_NAME_LEN]; |
54 | ||
a9909c21 | 55 | /* |
cd878479 | 56 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
57 | * level driver of CPUFreq support, and its spinlock. This lock |
58 | * also protects the cpufreq_cpu_data array. | |
59 | */ | |
1c3d85dd | 60 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 61 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 62 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 63 | |
874f6353 IV |
64 | static DEFINE_STATIC_KEY_FALSE(cpufreq_freq_invariance); |
65 | bool cpufreq_supports_freq_invariance(void) | |
66 | { | |
67 | return static_branch_likely(&cpufreq_freq_invariance); | |
68 | } | |
69 | ||
2f0aea93 VK |
70 | /* Flag to suspend/resume CPUFreq governors */ |
71 | static bool cpufreq_suspended; | |
1da177e4 | 72 | |
9c0ebcf7 VK |
73 | static inline bool has_target(void) |
74 | { | |
75 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
76 | } | |
77 | ||
1da177e4 | 78 | /* internal prototypes */ |
d92d50a4 | 79 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
80 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
81 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
a92604b4 | 82 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); |
1e4f63ae RW |
83 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
84 | struct cpufreq_governor *new_gov, | |
85 | unsigned int new_pol); | |
45482c70 | 86 | |
a9909c21 | 87 | /* |
32ee8c3e DJ |
88 | * Two notifier lists: the "policy" list is involved in the |
89 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
90 | * "transition" list for kernel code that needs to handle |
91 | * changes to devices when the CPU clock speed changes. | |
92 | * The mutex locks both lists. | |
93 | */ | |
e041c683 | 94 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 95 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 96 | |
a7b422cd | 97 | static int off __read_mostly; |
da584455 | 98 | static int cpufreq_disabled(void) |
a7b422cd KRW |
99 | { |
100 | return off; | |
101 | } | |
102 | void disable_cpufreq(void) | |
103 | { | |
104 | off = 1; | |
105 | } | |
29464f28 | 106 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 107 | |
4d5dcc42 VK |
108 | bool have_governor_per_policy(void) |
109 | { | |
0b981e70 | 110 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 111 | } |
3f869d6d | 112 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 113 | |
183edb20 YL |
114 | static struct kobject *cpufreq_global_kobject; |
115 | ||
944e9a03 VK |
116 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
117 | { | |
118 | if (have_governor_per_policy()) | |
119 | return &policy->kobj; | |
120 | else | |
121 | return cpufreq_global_kobject; | |
122 | } | |
123 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
124 | ||
72a4ce34 VK |
125 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
126 | { | |
5720821b | 127 | struct kernel_cpustat kcpustat; |
72a4ce34 | 128 | u64 cur_wall_time; |
5720821b | 129 | u64 idle_time; |
72a4ce34 VK |
130 | u64 busy_time; |
131 | ||
7fb1327e | 132 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 | 133 | |
5720821b FW |
134 | kcpustat_cpu_fetch(&kcpustat, cpu); |
135 | ||
136 | busy_time = kcpustat.cpustat[CPUTIME_USER]; | |
137 | busy_time += kcpustat.cpustat[CPUTIME_SYSTEM]; | |
138 | busy_time += kcpustat.cpustat[CPUTIME_IRQ]; | |
139 | busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ]; | |
140 | busy_time += kcpustat.cpustat[CPUTIME_STEAL]; | |
141 | busy_time += kcpustat.cpustat[CPUTIME_NICE]; | |
72a4ce34 VK |
142 | |
143 | idle_time = cur_wall_time - busy_time; | |
144 | if (wall) | |
7fb1327e | 145 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 146 | |
7fb1327e | 147 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
148 | } |
149 | ||
150 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
151 | { | |
152 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
153 | ||
154 | if (idle_time == -1ULL) | |
155 | return get_cpu_idle_time_jiffy(cpu, wall); | |
156 | else if (!io_busy) | |
157 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
158 | ||
159 | return idle_time; | |
160 | } | |
161 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
162 | ||
70e9e778 VK |
163 | /* |
164 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
165 | * drivers of SMP systems. It will do following: | |
166 | * - validate & show freq table passed | |
167 | * - set policies transition latency | |
168 | * - policy->cpus with all possible CPUs | |
169 | */ | |
c4dcc8a1 | 170 | void cpufreq_generic_init(struct cpufreq_policy *policy, |
70e9e778 VK |
171 | struct cpufreq_frequency_table *table, |
172 | unsigned int transition_latency) | |
173 | { | |
92c99d15 | 174 | policy->freq_table = table; |
70e9e778 VK |
175 | policy->cpuinfo.transition_latency = transition_latency; |
176 | ||
177 | /* | |
58405af6 | 178 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
179 | * share the clock and voltage and clock. |
180 | */ | |
181 | cpumask_setall(policy->cpus); | |
70e9e778 VK |
182 | } |
183 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
184 | ||
1f0bd44e | 185 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
186 | { |
187 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
188 | ||
988bed09 VK |
189 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
190 | } | |
1f0bd44e | 191 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
192 | |
193 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
194 | { | |
195 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
196 | ||
652ed95d | 197 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
198 | pr_err("%s: No %s associated to cpu: %d\n", |
199 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
200 | return 0; |
201 | } | |
202 | ||
203 | return clk_get_rate(policy->clk) / 1000; | |
204 | } | |
205 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
206 | ||
50e9c852 | 207 | /** |
5d094fea RW |
208 | * cpufreq_cpu_get - Return policy for a CPU and mark it as busy. |
209 | * @cpu: CPU to find the policy for. | |
50e9c852 | 210 | * |
5d094fea RW |
211 | * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment |
212 | * the kobject reference counter of that policy. Return a valid policy on | |
213 | * success or NULL on failure. | |
50e9c852 | 214 | * |
5d094fea RW |
215 | * The policy returned by this function has to be released with the help of |
216 | * cpufreq_cpu_put() to balance its kobject reference counter properly. | |
50e9c852 | 217 | */ |
6eed9404 | 218 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 219 | { |
6eed9404 | 220 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
221 | unsigned long flags; |
222 | ||
1b947c90 | 223 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
224 | return NULL; |
225 | ||
1da177e4 | 226 | /* get the cpufreq driver */ |
1c3d85dd | 227 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 228 | |
6eed9404 VK |
229 | if (cpufreq_driver) { |
230 | /* get the CPU */ | |
988bed09 | 231 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
232 | if (policy) |
233 | kobject_get(&policy->kobj); | |
234 | } | |
1da177e4 | 235 | |
6eed9404 | 236 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 237 | |
3a3e9e06 | 238 | return policy; |
a9144436 | 239 | } |
1da177e4 LT |
240 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
241 | ||
50e9c852 | 242 | /** |
5d094fea RW |
243 | * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy. |
244 | * @policy: cpufreq policy returned by cpufreq_cpu_get(). | |
50e9c852 | 245 | */ |
3a3e9e06 | 246 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 247 | { |
6eed9404 | 248 | kobject_put(&policy->kobj); |
1da177e4 LT |
249 | } |
250 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
251 | ||
540a3758 RW |
252 | /** |
253 | * cpufreq_cpu_release - Unlock a policy and decrement its usage counter. | |
254 | * @policy: cpufreq policy returned by cpufreq_cpu_acquire(). | |
255 | */ | |
9083e498 | 256 | void cpufreq_cpu_release(struct cpufreq_policy *policy) |
540a3758 RW |
257 | { |
258 | if (WARN_ON(!policy)) | |
259 | return; | |
260 | ||
261 | lockdep_assert_held(&policy->rwsem); | |
262 | ||
263 | up_write(&policy->rwsem); | |
264 | ||
265 | cpufreq_cpu_put(policy); | |
266 | } | |
267 | ||
268 | /** | |
269 | * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it. | |
270 | * @cpu: CPU to find the policy for. | |
271 | * | |
272 | * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and | |
273 | * if the policy returned by it is not NULL, acquire its rwsem for writing. | |
274 | * Return the policy if it is active or release it and return NULL otherwise. | |
275 | * | |
276 | * The policy returned by this function has to be released with the help of | |
277 | * cpufreq_cpu_release() in order to release its rwsem and balance its usage | |
278 | * counter properly. | |
279 | */ | |
9083e498 | 280 | struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) |
540a3758 RW |
281 | { |
282 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
283 | ||
284 | if (!policy) | |
285 | return NULL; | |
286 | ||
287 | down_write(&policy->rwsem); | |
288 | ||
289 | if (policy_is_inactive(policy)) { | |
290 | cpufreq_cpu_release(policy); | |
291 | return NULL; | |
292 | } | |
293 | ||
294 | return policy; | |
295 | } | |
296 | ||
1da177e4 LT |
297 | /********************************************************************* |
298 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
299 | *********************************************************************/ | |
300 | ||
ec06e586 RW |
301 | /** |
302 | * adjust_jiffies - Adjust the system "loops_per_jiffy". | |
303 | * @val: CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
304 | * @ci: Frequency change information. | |
1da177e4 LT |
305 | * |
306 | * This function alters the system "loops_per_jiffy" for the clock | |
307 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 308 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
309 | * per-CPU loops_per_jiffy value wherever possible. |
310 | */ | |
858119e1 | 311 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 312 | { |
39c132ee VK |
313 | #ifndef CONFIG_SMP |
314 | static unsigned long l_p_j_ref; | |
315 | static unsigned int l_p_j_ref_freq; | |
316 | ||
1da177e4 LT |
317 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
318 | return; | |
319 | ||
320 | if (!l_p_j_ref_freq) { | |
321 | l_p_j_ref = loops_per_jiffy; | |
322 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
323 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
324 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 325 | } |
0b443ead | 326 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
327 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
328 | ci->new); | |
e837f9b5 JP |
329 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
330 | loops_per_jiffy, ci->new); | |
1da177e4 | 331 | } |
1da177e4 | 332 | #endif |
39c132ee | 333 | } |
1da177e4 | 334 | |
20b5324d | 335 | /** |
ec06e586 | 336 | * cpufreq_notify_transition - Notify frequency transition and adjust jiffies. |
20b5324d VK |
337 | * @policy: cpufreq policy to enable fast frequency switching for. |
338 | * @freqs: contain details of the frequency update. | |
339 | * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
340 | * | |
ec06e586 RW |
341 | * This function calls the transition notifiers and adjust_jiffies(). |
342 | * | |
343 | * It is called twice on all CPU frequency changes that have external effects. | |
20b5324d VK |
344 | */ |
345 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
346 | struct cpufreq_freqs *freqs, | |
347 | unsigned int state) | |
1da177e4 | 348 | { |
df24014a VK |
349 | int cpu; |
350 | ||
1da177e4 LT |
351 | BUG_ON(irqs_disabled()); |
352 | ||
d5aaffa9 DB |
353 | if (cpufreq_disabled()) |
354 | return; | |
355 | ||
df24014a | 356 | freqs->policy = policy; |
1c3d85dd | 357 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 358 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 359 | state, freqs->new); |
1da177e4 | 360 | |
1da177e4 LT |
361 | switch (state) { |
362 | case CPUFREQ_PRECHANGE: | |
20b5324d VK |
363 | /* |
364 | * Detect if the driver reported a value as "old frequency" | |
e4472cb3 DJ |
365 | * which is not equal to what the cpufreq core thinks is |
366 | * "old frequency". | |
1da177e4 | 367 | */ |
98015228 VK |
368 | if (policy->cur && policy->cur != freqs->old) { |
369 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", | |
370 | freqs->old, policy->cur); | |
371 | freqs->old = policy->cur; | |
1da177e4 | 372 | } |
20b5324d | 373 | |
df24014a VK |
374 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
375 | CPUFREQ_PRECHANGE, freqs); | |
20b5324d | 376 | |
1da177e4 LT |
377 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
378 | break; | |
e4472cb3 | 379 | |
1da177e4 LT |
380 | case CPUFREQ_POSTCHANGE: |
381 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
20b5324d VK |
382 | pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, |
383 | cpumask_pr_args(policy->cpus)); | |
384 | ||
df24014a VK |
385 | for_each_cpu(cpu, policy->cpus) |
386 | trace_cpu_frequency(freqs->new, cpu); | |
387 | ||
388 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, | |
389 | CPUFREQ_POSTCHANGE, freqs); | |
20b5324d | 390 | |
1aefc75b | 391 | cpufreq_stats_record_transition(policy, freqs->new); |
20b5324d | 392 | policy->cur = freqs->new; |
1da177e4 | 393 | } |
1da177e4 | 394 | } |
bb176f7d | 395 | |
f7ba3b41 | 396 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 397 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
398 | struct cpufreq_freqs *freqs, int transition_failed) |
399 | { | |
400 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
401 | if (!transition_failed) | |
402 | return; | |
403 | ||
404 | swap(freqs->old, freqs->new); | |
405 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
406 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
407 | } | |
f7ba3b41 | 408 | |
12478cf0 SB |
409 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
410 | struct cpufreq_freqs *freqs) | |
411 | { | |
ca654dc3 SB |
412 | |
413 | /* | |
414 | * Catch double invocations of _begin() which lead to self-deadlock. | |
415 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
416 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
417 | * double invocations are very low. Moreover, there are scenarios | |
418 | * where these checks can emit false-positive warnings in these | |
419 | * drivers; so we avoid that by skipping them altogether. | |
420 | */ | |
421 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
422 | && current == policy->transition_task); | |
423 | ||
12478cf0 SB |
424 | wait: |
425 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
426 | ||
427 | spin_lock(&policy->transition_lock); | |
428 | ||
429 | if (unlikely(policy->transition_ongoing)) { | |
430 | spin_unlock(&policy->transition_lock); | |
431 | goto wait; | |
432 | } | |
433 | ||
434 | policy->transition_ongoing = true; | |
ca654dc3 | 435 | policy->transition_task = current; |
12478cf0 SB |
436 | |
437 | spin_unlock(&policy->transition_lock); | |
438 | ||
439 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
440 | } | |
441 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
442 | ||
443 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
444 | struct cpufreq_freqs *freqs, int transition_failed) | |
445 | { | |
0e7ea2f3 | 446 | if (WARN_ON(!policy->transition_ongoing)) |
12478cf0 SB |
447 | return; |
448 | ||
449 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
450 | ||
1a0419b0 IV |
451 | arch_set_freq_scale(policy->related_cpus, |
452 | policy->cur, | |
453 | policy->cpuinfo.max_freq); | |
454 | ||
12478cf0 | 455 | policy->transition_ongoing = false; |
ca654dc3 | 456 | policy->transition_task = NULL; |
12478cf0 SB |
457 | |
458 | wake_up(&policy->transition_wait); | |
459 | } | |
460 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
461 | ||
b7898fda RW |
462 | /* |
463 | * Fast frequency switching status count. Positive means "enabled", negative | |
464 | * means "disabled" and 0 means "not decided yet". | |
465 | */ | |
466 | static int cpufreq_fast_switch_count; | |
467 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
468 | ||
469 | static void cpufreq_list_transition_notifiers(void) | |
470 | { | |
471 | struct notifier_block *nb; | |
472 | ||
473 | pr_info("Registered transition notifiers:\n"); | |
474 | ||
475 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
476 | ||
477 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
d75f773c | 478 | pr_info("%pS\n", nb->notifier_call); |
b7898fda RW |
479 | |
480 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
481 | } | |
482 | ||
483 | /** | |
484 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
485 | * @policy: cpufreq policy to enable fast frequency switching for. | |
486 | * | |
487 | * Try to enable fast frequency switching for @policy. | |
488 | * | |
489 | * The attempt will fail if there is at least one transition notifier registered | |
490 | * at this point, as fast frequency switching is quite fundamentally at odds | |
491 | * with transition notifiers. Thus if successful, it will make registration of | |
492 | * transition notifiers fail going forward. | |
493 | */ | |
494 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
495 | { | |
496 | lockdep_assert_held(&policy->rwsem); | |
497 | ||
498 | if (!policy->fast_switch_possible) | |
499 | return; | |
500 | ||
501 | mutex_lock(&cpufreq_fast_switch_lock); | |
502 | if (cpufreq_fast_switch_count >= 0) { | |
503 | cpufreq_fast_switch_count++; | |
504 | policy->fast_switch_enabled = true; | |
505 | } else { | |
506 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
507 | policy->cpu); | |
508 | cpufreq_list_transition_notifiers(); | |
509 | } | |
510 | mutex_unlock(&cpufreq_fast_switch_lock); | |
511 | } | |
512 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
513 | ||
6c9d9c81 RW |
514 | /** |
515 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
516 | * @policy: cpufreq policy to disable fast frequency switching for. | |
517 | */ | |
518 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
519 | { |
520 | mutex_lock(&cpufreq_fast_switch_lock); | |
521 | if (policy->fast_switch_enabled) { | |
522 | policy->fast_switch_enabled = false; | |
523 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
524 | cpufreq_fast_switch_count--; | |
525 | } | |
526 | mutex_unlock(&cpufreq_fast_switch_lock); | |
527 | } | |
6c9d9c81 | 528 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 529 | |
e3c06236 SM |
530 | /** |
531 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
532 | * one. | |
a9909c21 | 533 | * @policy: associated policy to interrogate |
e3c06236 SM |
534 | * @target_freq: target frequency to resolve. |
535 | * | |
536 | * The target to driver frequency mapping is cached in the policy. | |
537 | * | |
538 | * Return: Lowest driver-supported frequency greater than or equal to the | |
539 | * given target_freq, subject to policy (min/max) and driver limitations. | |
540 | */ | |
541 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
542 | unsigned int target_freq) | |
543 | { | |
544 | target_freq = clamp_val(target_freq, policy->min, policy->max); | |
545 | policy->cached_target_freq = target_freq; | |
abe8bd02 VK |
546 | |
547 | if (cpufreq_driver->target_index) { | |
292072c3 | 548 | unsigned int idx; |
abe8bd02 VK |
549 | |
550 | idx = cpufreq_frequency_table_target(policy, target_freq, | |
551 | CPUFREQ_RELATION_L); | |
552 | policy->cached_resolved_idx = idx; | |
553 | return policy->freq_table[idx].frequency; | |
554 | } | |
555 | ||
e3c06236 SM |
556 | if (cpufreq_driver->resolve_freq) |
557 | return cpufreq_driver->resolve_freq(policy, target_freq); | |
abe8bd02 VK |
558 | |
559 | return target_freq; | |
e3c06236 | 560 | } |
ae2c1ca6 | 561 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 562 | |
aa7519af VK |
563 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
564 | { | |
565 | unsigned int latency; | |
566 | ||
567 | if (policy->transition_delay_us) | |
568 | return policy->transition_delay_us; | |
569 | ||
570 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
571 | if (latency) { |
572 | /* | |
573 | * For platforms that can change the frequency very fast (< 10 | |
574 | * us), the above formula gives a decent transition delay. But | |
575 | * for platforms where transition_latency is in milliseconds, it | |
576 | * ends up giving unrealistic values. | |
577 | * | |
578 | * Cap the default transition delay to 10 ms, which seems to be | |
579 | * a reasonable amount of time after which we should reevaluate | |
580 | * the frequency. | |
581 | */ | |
582 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
583 | } | |
aa7519af VK |
584 | |
585 | return LATENCY_MULTIPLIER; | |
586 | } | |
587 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
588 | ||
1da177e4 LT |
589 | /********************************************************************* |
590 | * SYSFS INTERFACE * | |
591 | *********************************************************************/ | |
8a5c74a1 | 592 | static ssize_t show_boost(struct kobject *kobj, |
625c85a6 | 593 | struct kobj_attribute *attr, char *buf) |
6f19efc0 LM |
594 | { |
595 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
596 | } | |
597 | ||
625c85a6 VK |
598 | static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, |
599 | const char *buf, size_t count) | |
6f19efc0 LM |
600 | { |
601 | int ret, enable; | |
602 | ||
603 | ret = sscanf(buf, "%d", &enable); | |
604 | if (ret != 1 || enable < 0 || enable > 1) | |
605 | return -EINVAL; | |
606 | ||
607 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
608 | pr_err("%s: Cannot %s BOOST!\n", |
609 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
610 | return -EINVAL; |
611 | } | |
612 | ||
e837f9b5 JP |
613 | pr_debug("%s: cpufreq BOOST %s\n", |
614 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
615 | |
616 | return count; | |
617 | } | |
618 | define_one_global_rw(boost); | |
1da177e4 | 619 | |
42f91fa1 | 620 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
621 | { |
622 | struct cpufreq_governor *t; | |
623 | ||
f7b27061 | 624 | for_each_governor(t) |
7c4f4539 | 625 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
626 | return t; |
627 | ||
628 | return NULL; | |
629 | } | |
630 | ||
8cc46ae5 VK |
631 | static struct cpufreq_governor *get_governor(const char *str_governor) |
632 | { | |
633 | struct cpufreq_governor *t; | |
634 | ||
635 | mutex_lock(&cpufreq_governor_mutex); | |
636 | t = find_governor(str_governor); | |
637 | if (!t) | |
638 | goto unlock; | |
639 | ||
640 | if (!try_module_get(t->owner)) | |
641 | t = NULL; | |
642 | ||
643 | unlock: | |
644 | mutex_unlock(&cpufreq_governor_mutex); | |
645 | ||
646 | return t; | |
647 | } | |
648 | ||
1e4f63ae | 649 | static unsigned int cpufreq_parse_policy(char *str_governor) |
ab05d97a | 650 | { |
1e4f63ae RW |
651 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) |
652 | return CPUFREQ_POLICY_PERFORMANCE; | |
653 | ||
654 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) | |
655 | return CPUFREQ_POLICY_POWERSAVE; | |
656 | ||
657 | return CPUFREQ_POLICY_UNKNOWN; | |
ab05d97a YH |
658 | } |
659 | ||
1da177e4 | 660 | /** |
5ddc6d4e | 661 | * cpufreq_parse_governor - parse a governor string only for has_target() |
1e4f63ae | 662 | * @str_governor: Governor name. |
1da177e4 | 663 | */ |
1e4f63ae | 664 | static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor) |
1da177e4 | 665 | { |
ab05d97a | 666 | struct cpufreq_governor *t; |
045149e6 | 667 | |
8cc46ae5 VK |
668 | t = get_governor(str_governor); |
669 | if (t) | |
670 | return t; | |
ea714970 | 671 | |
8cc46ae5 VK |
672 | if (request_module("cpufreq_%s", str_governor)) |
673 | return NULL; | |
045149e6 | 674 | |
8cc46ae5 | 675 | return get_governor(str_governor); |
1da177e4 | 676 | } |
1da177e4 | 677 | |
a9909c21 | 678 | /* |
e08f5f5b GS |
679 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
680 | * print out cpufreq information | |
1da177e4 LT |
681 | * |
682 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
683 | * "unsigned int". | |
684 | */ | |
685 | ||
32ee8c3e DJ |
686 | #define show_one(file_name, object) \ |
687 | static ssize_t show_##file_name \ | |
905d77cd | 688 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 689 | { \ |
29464f28 | 690 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
691 | } |
692 | ||
693 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
694 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 695 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
696 | show_one(scaling_min_freq, min); |
697 | show_one(scaling_max_freq, max); | |
c034b02e | 698 | |
f8475cef LB |
699 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
700 | { | |
701 | return 0; | |
702 | } | |
703 | ||
09347b29 | 704 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
705 | { |
706 | ssize_t ret; | |
f8475cef | 707 | unsigned int freq; |
c034b02e | 708 | |
f8475cef LB |
709 | freq = arch_freq_get_on_cpu(policy->cpu); |
710 | if (freq) | |
711 | ret = sprintf(buf, "%u\n", freq); | |
681fe684 | 712 | else if (cpufreq_driver->setpolicy && cpufreq_driver->get) |
c034b02e DB |
713 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
714 | else | |
715 | ret = sprintf(buf, "%u\n", policy->cur); | |
716 | return ret; | |
717 | } | |
1da177e4 | 718 | |
a9909c21 | 719 | /* |
1da177e4 LT |
720 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access |
721 | */ | |
722 | #define store_one(file_name, object) \ | |
723 | static ssize_t store_##file_name \ | |
905d77cd | 724 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 725 | { \ |
18c49926 VK |
726 | unsigned long val; \ |
727 | int ret; \ | |
1da177e4 | 728 | \ |
18c49926 | 729 | ret = sscanf(buf, "%lu", &val); \ |
1da177e4 LT |
730 | if (ret != 1) \ |
731 | return -EINVAL; \ | |
732 | \ | |
3000ce3c | 733 | ret = freq_qos_update_request(policy->object##_freq_req, val);\ |
18c49926 | 734 | return ret >= 0 ? count : ret; \ |
1da177e4 LT |
735 | } |
736 | ||
29464f28 DJ |
737 | store_one(scaling_min_freq, min); |
738 | store_one(scaling_max_freq, max); | |
1da177e4 | 739 | |
a9909c21 | 740 | /* |
1da177e4 LT |
741 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware |
742 | */ | |
905d77cd DJ |
743 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
744 | char *buf) | |
1da177e4 | 745 | { |
d92d50a4 | 746 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
747 | |
748 | if (cur_freq) | |
749 | return sprintf(buf, "%u\n", cur_freq); | |
750 | ||
751 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
752 | } |
753 | ||
a9909c21 | 754 | /* |
1da177e4 LT |
755 | * show_scaling_governor - show the current policy for the specified CPU |
756 | */ | |
905d77cd | 757 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 758 | { |
29464f28 | 759 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
760 | return sprintf(buf, "powersave\n"); |
761 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
762 | return sprintf(buf, "performance\n"); | |
763 | else if (policy->governor) | |
4b972f0b | 764 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 765 | policy->governor->name); |
1da177e4 LT |
766 | return -EINVAL; |
767 | } | |
768 | ||
a9909c21 | 769 | /* |
1da177e4 LT |
770 | * store_scaling_governor - store policy for the specified CPU |
771 | */ | |
905d77cd DJ |
772 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
773 | const char *buf, size_t count) | |
1da177e4 | 774 | { |
1e4f63ae | 775 | char str_governor[16]; |
5136fa56 | 776 | int ret; |
1da177e4 | 777 | |
29464f28 | 778 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
779 | if (ret != 1) |
780 | return -EINVAL; | |
781 | ||
ab05d97a | 782 | if (cpufreq_driver->setpolicy) { |
1e4f63ae RW |
783 | unsigned int new_pol; |
784 | ||
785 | new_pol = cpufreq_parse_policy(str_governor); | |
786 | if (!new_pol) | |
ab05d97a | 787 | return -EINVAL; |
1e4f63ae RW |
788 | |
789 | ret = cpufreq_set_policy(policy, NULL, new_pol); | |
ab05d97a | 790 | } else { |
1e4f63ae RW |
791 | struct cpufreq_governor *new_gov; |
792 | ||
793 | new_gov = cpufreq_parse_governor(str_governor); | |
794 | if (!new_gov) | |
ab05d97a | 795 | return -EINVAL; |
1da177e4 | 796 | |
1e4f63ae RW |
797 | ret = cpufreq_set_policy(policy, new_gov, |
798 | CPUFREQ_POLICY_UNKNOWN); | |
a8b149d3 | 799 | |
1e4f63ae RW |
800 | module_put(new_gov->owner); |
801 | } | |
a8b149d3 | 802 | |
88dc4384 | 803 | return ret ? ret : count; |
1da177e4 LT |
804 | } |
805 | ||
a9909c21 | 806 | /* |
1da177e4 LT |
807 | * show_scaling_driver - show the cpufreq driver currently loaded |
808 | */ | |
905d77cd | 809 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 810 | { |
1c3d85dd | 811 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
812 | } |
813 | ||
a9909c21 | 814 | /* |
1da177e4 LT |
815 | * show_scaling_available_governors - show the available CPUfreq governors |
816 | */ | |
905d77cd DJ |
817 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
818 | char *buf) | |
1da177e4 LT |
819 | { |
820 | ssize_t i = 0; | |
821 | struct cpufreq_governor *t; | |
822 | ||
9c0ebcf7 | 823 | if (!has_target()) { |
1da177e4 LT |
824 | i += sprintf(buf, "performance powersave"); |
825 | goto out; | |
826 | } | |
827 | ||
8cc46ae5 | 828 | mutex_lock(&cpufreq_governor_mutex); |
f7b27061 | 829 | for_each_governor(t) { |
29464f28 DJ |
830 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
831 | - (CPUFREQ_NAME_LEN + 2))) | |
8cc46ae5 | 832 | break; |
4b972f0b | 833 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 834 | } |
8cc46ae5 | 835 | mutex_unlock(&cpufreq_governor_mutex); |
7d5e350f | 836 | out: |
1da177e4 LT |
837 | i += sprintf(&buf[i], "\n"); |
838 | return i; | |
839 | } | |
e8628dd0 | 840 | |
f4fd3797 | 841 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
842 | { |
843 | ssize_t i = 0; | |
844 | unsigned int cpu; | |
845 | ||
835481d9 | 846 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
847 | if (i) |
848 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
849 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
850 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 851 | break; |
1da177e4 LT |
852 | } |
853 | i += sprintf(&buf[i], "\n"); | |
854 | return i; | |
855 | } | |
f4fd3797 | 856 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 857 | |
a9909c21 | 858 | /* |
e8628dd0 DW |
859 | * show_related_cpus - show the CPUs affected by each transition even if |
860 | * hw coordination is in use | |
861 | */ | |
862 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
863 | { | |
f4fd3797 | 864 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
865 | } |
866 | ||
a9909c21 | 867 | /* |
e8628dd0 DW |
868 | * show_affected_cpus - show the CPUs affected by each transition |
869 | */ | |
870 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
871 | { | |
f4fd3797 | 872 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
873 | } |
874 | ||
9e76988e | 875 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 876 | const char *buf, size_t count) |
9e76988e VP |
877 | { |
878 | unsigned int freq = 0; | |
879 | unsigned int ret; | |
880 | ||
879000f9 | 881 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
882 | return -EINVAL; |
883 | ||
884 | ret = sscanf(buf, "%u", &freq); | |
885 | if (ret != 1) | |
886 | return -EINVAL; | |
887 | ||
888 | policy->governor->store_setspeed(policy, freq); | |
889 | ||
890 | return count; | |
891 | } | |
892 | ||
893 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
894 | { | |
879000f9 | 895 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
896 | return sprintf(buf, "<unsupported>\n"); |
897 | ||
898 | return policy->governor->show_setspeed(policy, buf); | |
899 | } | |
1da177e4 | 900 | |
a9909c21 | 901 | /* |
8bf1ac72 | 902 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
903 | */ |
904 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
905 | { | |
906 | unsigned int limit; | |
907 | int ret; | |
b23aa311 YH |
908 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
909 | if (!ret) | |
910 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
911 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
912 | } | |
913 | ||
6dad2a29 BP |
914 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
915 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
916 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
917 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
918 | cpufreq_freq_attr_ro(scaling_available_governors); | |
919 | cpufreq_freq_attr_ro(scaling_driver); | |
920 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
921 | cpufreq_freq_attr_ro(bios_limit); | |
922 | cpufreq_freq_attr_ro(related_cpus); | |
923 | cpufreq_freq_attr_ro(affected_cpus); | |
924 | cpufreq_freq_attr_rw(scaling_min_freq); | |
925 | cpufreq_freq_attr_rw(scaling_max_freq); | |
926 | cpufreq_freq_attr_rw(scaling_governor); | |
927 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 928 | |
905d77cd | 929 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
930 | &cpuinfo_min_freq.attr, |
931 | &cpuinfo_max_freq.attr, | |
ed129784 | 932 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
933 | &scaling_min_freq.attr, |
934 | &scaling_max_freq.attr, | |
935 | &affected_cpus.attr, | |
e8628dd0 | 936 | &related_cpus.attr, |
1da177e4 LT |
937 | &scaling_governor.attr, |
938 | &scaling_driver.attr, | |
939 | &scaling_available_governors.attr, | |
9e76988e | 940 | &scaling_setspeed.attr, |
1da177e4 LT |
941 | NULL |
942 | }; | |
943 | ||
29464f28 DJ |
944 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
945 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 946 | |
29464f28 | 947 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 948 | { |
905d77cd DJ |
949 | struct cpufreq_policy *policy = to_policy(kobj); |
950 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 951 | ssize_t ret; |
6eed9404 | 952 | |
e6e8df07 KS |
953 | if (!fattr->show) |
954 | return -EIO; | |
955 | ||
ad7722da | 956 | down_read(&policy->rwsem); |
6541aef0 | 957 | ret = fattr->show(policy, buf); |
ad7722da | 958 | up_read(&policy->rwsem); |
1b750e3b | 959 | |
1da177e4 LT |
960 | return ret; |
961 | } | |
962 | ||
905d77cd DJ |
963 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
964 | const char *buf, size_t count) | |
1da177e4 | 965 | { |
905d77cd DJ |
966 | struct cpufreq_policy *policy = to_policy(kobj); |
967 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 968 | ssize_t ret = -EINVAL; |
6eed9404 | 969 | |
e6e8df07 KS |
970 | if (!fattr->store) |
971 | return -EIO; | |
972 | ||
9b3d9bb3 WL |
973 | /* |
974 | * cpus_read_trylock() is used here to work around a circular lock | |
975 | * dependency problem with respect to the cpufreq_register_driver(). | |
976 | */ | |
977 | if (!cpus_read_trylock()) | |
978 | return -EBUSY; | |
4f750c93 | 979 | |
6541aef0 RW |
980 | if (cpu_online(policy->cpu)) { |
981 | down_write(&policy->rwsem); | |
e08f5f5b | 982 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
983 | up_write(&policy->rwsem); |
984 | } | |
e08f5f5b | 985 | |
a92551e4 | 986 | cpus_read_unlock(); |
4f750c93 | 987 | |
1da177e4 LT |
988 | return ret; |
989 | } | |
990 | ||
905d77cd | 991 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 992 | { |
905d77cd | 993 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 994 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
995 | complete(&policy->kobj_unregister); |
996 | } | |
997 | ||
52cf25d0 | 998 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
999 | .show = show, |
1000 | .store = store, | |
1001 | }; | |
1002 | ||
1003 | static struct kobj_type ktype_cpufreq = { | |
1004 | .sysfs_ops = &sysfs_ops, | |
1005 | .default_attrs = default_attrs, | |
1006 | .release = cpufreq_sysfs_release, | |
1007 | }; | |
1008 | ||
2f0ba790 | 1009 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) |
87549141 | 1010 | { |
2f0ba790 RW |
1011 | struct device *dev = get_cpu_device(cpu); |
1012 | ||
67d874c3 | 1013 | if (unlikely(!dev)) |
2f0ba790 RW |
1014 | return; |
1015 | ||
1016 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
1017 | return; | |
1018 | ||
26619804 | 1019 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
1020 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
1021 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
1022 | } |
1023 | ||
26619804 VK |
1024 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
1025 | struct device *dev) | |
87549141 | 1026 | { |
26619804 VK |
1027 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1028 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
1029 | } |
1030 | ||
d9612a49 | 1031 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
1032 | { |
1033 | struct freq_attr **drv_attr; | |
909a694e | 1034 | int ret = 0; |
909a694e | 1035 | |
909a694e | 1036 | /* set up files for this cpu device */ |
1c3d85dd | 1037 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1038 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1039 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1040 | if (ret) | |
6d4e81ed | 1041 | return ret; |
909a694e DJ |
1042 | drv_attr++; |
1043 | } | |
1c3d85dd | 1044 | if (cpufreq_driver->get) { |
909a694e DJ |
1045 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1046 | if (ret) | |
6d4e81ed | 1047 | return ret; |
909a694e | 1048 | } |
c034b02e DB |
1049 | |
1050 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1051 | if (ret) | |
6d4e81ed | 1052 | return ret; |
c034b02e | 1053 | |
1c3d85dd | 1054 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1055 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1056 | if (ret) | |
6d4e81ed | 1057 | return ret; |
e2f74f35 | 1058 | } |
909a694e | 1059 | |
26619804 | 1060 | return 0; |
e18f1682 SB |
1061 | } |
1062 | ||
7f0fa40f | 1063 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1064 | { |
1e4f63ae RW |
1065 | struct cpufreq_governor *gov = NULL; |
1066 | unsigned int pol = CPUFREQ_POLICY_UNKNOWN; | |
8cc46ae5 | 1067 | int ret; |
ab05d97a YH |
1068 | |
1069 | if (has_target()) { | |
1e4f63ae | 1070 | /* Update policy governor to the one used before hotplug. */ |
8cc46ae5 | 1071 | gov = get_governor(policy->last_governor); |
ab05d97a YH |
1072 | if (gov) { |
1073 | pr_debug("Restoring governor %s for cpu %d\n", | |
8412b456 | 1074 | gov->name, policy->cpu); |
1e4f63ae | 1075 | } else { |
8412b456 QP |
1076 | gov = get_governor(default_governor); |
1077 | } | |
1078 | ||
1079 | if (!gov) { | |
1080 | gov = cpufreq_default_governor(); | |
8412b456 | 1081 | __module_get(gov->owner); |
ab05d97a | 1082 | } |
8412b456 | 1083 | |
de1df26b | 1084 | } else { |
8412b456 | 1085 | |
ab05d97a YH |
1086 | /* Use the default policy if there is no last_policy. */ |
1087 | if (policy->last_policy) { | |
1e4f63ae | 1088 | pol = policy->last_policy; |
8412b456 QP |
1089 | } else { |
1090 | pol = cpufreq_parse_policy(default_governor); | |
f5739cb0 | 1091 | /* |
8412b456 | 1092 | * In case the default governor is neither "performance" |
f5739cb0 RW |
1093 | * nor "powersave", fall back to the initial policy |
1094 | * value set by the driver. | |
1095 | */ | |
1096 | if (pol == CPUFREQ_POLICY_UNKNOWN) | |
1097 | pol = policy->policy; | |
ab05d97a | 1098 | } |
f5739cb0 RW |
1099 | if (pol != CPUFREQ_POLICY_PERFORMANCE && |
1100 | pol != CPUFREQ_POLICY_POWERSAVE) | |
1101 | return -ENODATA; | |
69030dd1 | 1102 | } |
ab05d97a | 1103 | |
8cc46ae5 VK |
1104 | ret = cpufreq_set_policy(policy, gov, pol); |
1105 | if (gov) | |
1106 | module_put(gov->owner); | |
1107 | ||
1108 | return ret; | |
909a694e DJ |
1109 | } |
1110 | ||
d9612a49 | 1111 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1112 | { |
9c0ebcf7 | 1113 | int ret = 0; |
fcf80582 | 1114 | |
bb29ae15 VK |
1115 | /* Has this CPU been taken care of already? */ |
1116 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1117 | return 0; | |
1118 | ||
49f18560 | 1119 | down_write(&policy->rwsem); |
45482c70 RW |
1120 | if (has_target()) |
1121 | cpufreq_stop_governor(policy); | |
fcf80582 | 1122 | |
fcf80582 | 1123 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1124 | |
9c0ebcf7 | 1125 | if (has_target()) { |
0a300767 | 1126 | ret = cpufreq_start_governor(policy); |
49f18560 | 1127 | if (ret) |
3de9bdeb | 1128 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1129 | } |
49f18560 VK |
1130 | up_write(&policy->rwsem); |
1131 | return ret; | |
fcf80582 | 1132 | } |
1da177e4 | 1133 | |
c57b25bd | 1134 | void refresh_frequency_limits(struct cpufreq_policy *policy) |
70a59fde | 1135 | { |
67d874c3 | 1136 | if (!policy_is_inactive(policy)) { |
67d874c3 | 1137 | pr_debug("updating policy for CPU %u\n", policy->cpu); |
70a59fde | 1138 | |
1e4f63ae | 1139 | cpufreq_set_policy(policy, policy->governor, policy->policy); |
67d874c3 | 1140 | } |
70a59fde | 1141 | } |
c57b25bd | 1142 | EXPORT_SYMBOL(refresh_frequency_limits); |
70a59fde | 1143 | |
11eb69b9 VK |
1144 | static void handle_update(struct work_struct *work) |
1145 | { | |
1146 | struct cpufreq_policy *policy = | |
1147 | container_of(work, struct cpufreq_policy, update); | |
70a59fde VK |
1148 | |
1149 | pr_debug("handle_update for cpu %u called\n", policy->cpu); | |
67d874c3 | 1150 | down_write(&policy->rwsem); |
70a59fde | 1151 | refresh_frequency_limits(policy); |
67d874c3 VK |
1152 | up_write(&policy->rwsem); |
1153 | } | |
1154 | ||
1155 | static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq, | |
1156 | void *data) | |
1157 | { | |
1158 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min); | |
1159 | ||
1160 | schedule_work(&policy->update); | |
1161 | return 0; | |
1162 | } | |
1163 | ||
1164 | static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq, | |
1165 | void *data) | |
1166 | { | |
1167 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max); | |
1168 | ||
1169 | schedule_work(&policy->update); | |
1170 | return 0; | |
1171 | } | |
1172 | ||
1173 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) | |
1174 | { | |
1175 | struct kobject *kobj; | |
1176 | struct completion *cmp; | |
1177 | ||
1178 | down_write(&policy->rwsem); | |
1179 | cpufreq_stats_free_table(policy); | |
1180 | kobj = &policy->kobj; | |
1181 | cmp = &policy->kobj_unregister; | |
1182 | up_write(&policy->rwsem); | |
1183 | kobject_put(kobj); | |
1184 | ||
1185 | /* | |
1186 | * We need to make sure that the underlying kobj is | |
1187 | * actually not referenced anymore by anybody before we | |
1188 | * proceed with unloading. | |
1189 | */ | |
1190 | pr_debug("waiting for dropping of refcount\n"); | |
1191 | wait_for_completion(cmp); | |
1192 | pr_debug("wait complete\n"); | |
fcf80582 | 1193 | } |
1da177e4 | 1194 | |
a34e63b1 | 1195 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1196 | { |
1197 | struct cpufreq_policy *policy; | |
67d874c3 | 1198 | struct device *dev = get_cpu_device(cpu); |
edd4a893 | 1199 | int ret; |
e9698cc5 | 1200 | |
67d874c3 VK |
1201 | if (!dev) |
1202 | return NULL; | |
1203 | ||
e9698cc5 SB |
1204 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1205 | if (!policy) | |
1206 | return NULL; | |
1207 | ||
1208 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1209 | goto err_free_policy; | |
1210 | ||
1211 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1212 | goto err_free_cpumask; | |
1213 | ||
559ed407 RW |
1214 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1215 | goto err_free_rcpumask; | |
1216 | ||
edd4a893 VK |
1217 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1218 | cpufreq_global_kobject, "policy%u", cpu); | |
1219 | if (ret) { | |
67d874c3 | 1220 | dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret); |
2acb9bda RW |
1221 | /* |
1222 | * The entire policy object will be freed below, but the extra | |
1223 | * memory allocated for the kobject name needs to be freed by | |
1224 | * releasing the kobject. | |
1225 | */ | |
4ebe36c9 | 1226 | kobject_put(&policy->kobj); |
edd4a893 VK |
1227 | goto err_free_real_cpus; |
1228 | } | |
1229 | ||
3000ce3c RW |
1230 | freq_constraints_init(&policy->constraints); |
1231 | ||
67d874c3 VK |
1232 | policy->nb_min.notifier_call = cpufreq_notifier_min; |
1233 | policy->nb_max.notifier_call = cpufreq_notifier_max; | |
1234 | ||
3000ce3c RW |
1235 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MIN, |
1236 | &policy->nb_min); | |
67d874c3 VK |
1237 | if (ret) { |
1238 | dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n", | |
1239 | ret, cpumask_pr_args(policy->cpus)); | |
1240 | goto err_kobj_remove; | |
1241 | } | |
1242 | ||
3000ce3c RW |
1243 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MAX, |
1244 | &policy->nb_max); | |
67d874c3 VK |
1245 | if (ret) { |
1246 | dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n", | |
1247 | ret, cpumask_pr_args(policy->cpus)); | |
1248 | goto err_min_qos_notifier; | |
1249 | } | |
1250 | ||
c88a1f8b | 1251 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1252 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1253 | spin_lock_init(&policy->transition_lock); |
1254 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1255 | init_completion(&policy->kobj_unregister); |
1256 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1257 | |
a34e63b1 | 1258 | policy->cpu = cpu; |
e9698cc5 SB |
1259 | return policy; |
1260 | ||
67d874c3 | 1261 | err_min_qos_notifier: |
3000ce3c RW |
1262 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, |
1263 | &policy->nb_min); | |
67d874c3 VK |
1264 | err_kobj_remove: |
1265 | cpufreq_policy_put_kobj(policy); | |
edd4a893 VK |
1266 | err_free_real_cpus: |
1267 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1268 | err_free_rcpumask: |
1269 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1270 | err_free_cpumask: |
1271 | free_cpumask_var(policy->cpus); | |
1272 | err_free_policy: | |
1273 | kfree(policy); | |
1274 | ||
1275 | return NULL; | |
1276 | } | |
1277 | ||
f9f41e3e | 1278 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1279 | { |
988bed09 VK |
1280 | unsigned long flags; |
1281 | int cpu; | |
1282 | ||
1283 | /* Remove policy from list */ | |
1284 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1285 | list_del(&policy->policy_list); | |
1286 | ||
1287 | for_each_cpu(cpu, policy->related_cpus) | |
1288 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1289 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1290 | ||
3000ce3c RW |
1291 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MAX, |
1292 | &policy->nb_max); | |
1293 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, | |
1294 | &policy->nb_min); | |
6a149036 | 1295 | |
6941051d SH |
1296 | /* Cancel any pending policy->update work before freeing the policy. */ |
1297 | cancel_work_sync(&policy->update); | |
6a149036 VK |
1298 | |
1299 | if (policy->max_freq_req) { | |
1300 | /* | |
1301 | * CPUFREQ_CREATE_POLICY notification is sent only after | |
1302 | * successfully adding max_freq_req request. | |
1303 | */ | |
1304 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1305 | CPUFREQ_REMOVE_POLICY, policy); | |
3000ce3c | 1306 | freq_qos_remove_request(policy->max_freq_req); |
6a149036 VK |
1307 | } |
1308 | ||
3000ce3c | 1309 | freq_qos_remove_request(policy->min_freq_req); |
18c49926 | 1310 | kfree(policy->min_freq_req); |
67d874c3 | 1311 | |
f9f41e3e | 1312 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1313 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1314 | free_cpumask_var(policy->related_cpus); |
1315 | free_cpumask_var(policy->cpus); | |
1316 | kfree(policy); | |
1317 | } | |
1318 | ||
0b275352 | 1319 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1320 | { |
7f0c020a | 1321 | struct cpufreq_policy *policy; |
194d99c7 | 1322 | bool new_policy; |
1da177e4 | 1323 | unsigned long flags; |
0b275352 RW |
1324 | unsigned int j; |
1325 | int ret; | |
87549141 | 1326 | |
0b275352 | 1327 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1328 | |
bb29ae15 | 1329 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1330 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1331 | if (policy) { |
9104bb26 | 1332 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1333 | if (!policy_is_inactive(policy)) |
d9612a49 | 1334 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1335 | |
11ce707e | 1336 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1337 | new_policy = false; |
11ce707e RW |
1338 | down_write(&policy->rwsem); |
1339 | policy->cpu = cpu; | |
1340 | policy->governor = NULL; | |
1341 | up_write(&policy->rwsem); | |
1342 | } else { | |
194d99c7 | 1343 | new_policy = true; |
a34e63b1 | 1344 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1345 | if (!policy) |
d4d854d6 | 1346 | return -ENOMEM; |
72368d12 | 1347 | } |
0d66b91e | 1348 | |
91a12e91 VK |
1349 | if (!new_policy && cpufreq_driver->online) { |
1350 | ret = cpufreq_driver->online(policy); | |
1351 | if (ret) { | |
1352 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1353 | __LINE__); | |
1354 | goto out_exit_policy; | |
1355 | } | |
1da177e4 | 1356 | |
91a12e91 VK |
1357 | /* Recover policy->cpus using related_cpus */ |
1358 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1359 | } else { | |
1360 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1361 | |
91a12e91 VK |
1362 | /* |
1363 | * Call driver. From then on the cpufreq must be able | |
1364 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1365 | */ | |
1366 | ret = cpufreq_driver->init(policy); | |
1367 | if (ret) { | |
1368 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1369 | __LINE__); | |
1370 | goto out_free_policy; | |
1371 | } | |
d417e069 | 1372 | |
91a12e91 VK |
1373 | ret = cpufreq_table_validate_and_sort(policy); |
1374 | if (ret) | |
1375 | goto out_exit_policy; | |
6d4e81ed | 1376 | |
4d1f3a5b | 1377 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1378 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1379 | } |
559ed407 | 1380 | |
91a12e91 | 1381 | down_write(&policy->rwsem); |
5a7e56a5 VK |
1382 | /* |
1383 | * affected cpus must always be the one, which are online. We aren't | |
1384 | * managing offline cpus here. | |
1385 | */ | |
1386 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1387 | ||
194d99c7 | 1388 | if (new_policy) { |
2f0ba790 | 1389 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1390 | per_cpu(cpufreq_cpu_data, j) = policy; |
2f0ba790 RW |
1391 | add_cpu_dev_symlink(policy, j); |
1392 | } | |
18c49926 VK |
1393 | |
1394 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1395 | GFP_KERNEL); | |
b96f0384 WS |
1396 | if (!policy->min_freq_req) { |
1397 | ret = -ENOMEM; | |
18c49926 | 1398 | goto out_destroy_policy; |
b96f0384 | 1399 | } |
18c49926 | 1400 | |
3000ce3c RW |
1401 | ret = freq_qos_add_request(&policy->constraints, |
1402 | policy->min_freq_req, FREQ_QOS_MIN, | |
1403 | policy->min); | |
18c49926 VK |
1404 | if (ret < 0) { |
1405 | /* | |
3000ce3c | 1406 | * So we don't call freq_qos_remove_request() for an |
18c49926 VK |
1407 | * uninitialized request. |
1408 | */ | |
1409 | kfree(policy->min_freq_req); | |
1410 | policy->min_freq_req = NULL; | |
18c49926 VK |
1411 | goto out_destroy_policy; |
1412 | } | |
1413 | ||
1414 | /* | |
1415 | * This must be initialized right here to avoid calling | |
3000ce3c | 1416 | * freq_qos_remove_request() on uninitialized request in case |
18c49926 VK |
1417 | * of errors. |
1418 | */ | |
1419 | policy->max_freq_req = policy->min_freq_req + 1; | |
1420 | ||
3000ce3c RW |
1421 | ret = freq_qos_add_request(&policy->constraints, |
1422 | policy->max_freq_req, FREQ_QOS_MAX, | |
1423 | policy->max); | |
18c49926 VK |
1424 | if (ret < 0) { |
1425 | policy->max_freq_req = NULL; | |
18c49926 VK |
1426 | goto out_destroy_policy; |
1427 | } | |
6a149036 VK |
1428 | |
1429 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1430 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1431 | } |
652ed95d | 1432 | |
5ddc6d4e | 1433 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1434 | policy->cur = cpufreq_driver->get(policy->cpu); |
1435 | if (!policy->cur) { | |
b96f0384 | 1436 | ret = -EIO; |
da60ce9f | 1437 | pr_err("%s: ->get() failed\n", __func__); |
d417e069 | 1438 | goto out_destroy_policy; |
da60ce9f VK |
1439 | } |
1440 | } | |
1441 | ||
d3916691 VK |
1442 | /* |
1443 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1444 | * frequency table present with cpufreq core. In such cases CPU might be | |
1445 | * unstable if it has to run on that frequency for long duration of time | |
1446 | * and so its better to set it to a frequency which is specified in | |
1447 | * freq-table. This also makes cpufreq stats inconsistent as | |
1448 | * cpufreq-stats would fail to register because current frequency of CPU | |
1449 | * isn't found in freq-table. | |
1450 | * | |
1451 | * Because we don't want this change to effect boot process badly, we go | |
1452 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1453 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1454 | * is initialized to zero). | |
1455 | * | |
1456 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1457 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1458 | * equal to target-freq. | |
1459 | */ | |
1460 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1461 | && has_target()) { | |
97148d0a VK |
1462 | unsigned int old_freq = policy->cur; |
1463 | ||
d3916691 | 1464 | /* Are we running at unknown frequency ? */ |
97148d0a | 1465 | ret = cpufreq_frequency_table_get_index(policy, old_freq); |
d3916691 | 1466 | if (ret == -EINVAL) { |
97148d0a VK |
1467 | ret = __cpufreq_driver_target(policy, old_freq - 1, |
1468 | CPUFREQ_RELATION_L); | |
d3916691 VK |
1469 | |
1470 | /* | |
1471 | * Reaching here after boot in a few seconds may not | |
1472 | * mean that system will remain stable at "unknown" | |
1473 | * frequency for longer duration. Hence, a BUG_ON(). | |
1474 | */ | |
1475 | BUG_ON(ret); | |
97148d0a VK |
1476 | pr_info("%s: CPU%d: Running at unlisted initial frequency: %u KHz, changing to: %u KHz\n", |
1477 | __func__, policy->cpu, old_freq, policy->cur); | |
d3916691 VK |
1478 | } |
1479 | } | |
1480 | ||
194d99c7 | 1481 | if (new_policy) { |
d9612a49 | 1482 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1483 | if (ret) |
d417e069 | 1484 | goto out_destroy_policy; |
1aefc75b RW |
1485 | |
1486 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1487 | |
988bed09 VK |
1488 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1489 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1490 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1491 | } | |
9515f4d6 | 1492 | |
7f0fa40f VK |
1493 | ret = cpufreq_init_policy(policy); |
1494 | if (ret) { | |
1495 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1496 | __func__, cpu, ret); | |
d417e069 | 1497 | goto out_destroy_policy; |
08fd8c1c | 1498 | } |
e18f1682 | 1499 | |
4e97b631 | 1500 | up_write(&policy->rwsem); |
08fd8c1c | 1501 | |
038c5b3e | 1502 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1503 | |
7c45cf31 VK |
1504 | /* Callback for handling stuff after policy is ready */ |
1505 | if (cpufreq_driver->ready) | |
1506 | cpufreq_driver->ready(policy); | |
1507 | ||
bcc61569 | 1508 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1509 | policy->cdev = of_cpufreq_cooling_register(policy); |
1510 | ||
2d06d8c4 | 1511 | pr_debug("initialization complete\n"); |
87c32271 | 1512 | |
1da177e4 LT |
1513 | return 0; |
1514 | ||
d417e069 | 1515 | out_destroy_policy: |
b24b6478 VK |
1516 | for_each_cpu(j, policy->real_cpus) |
1517 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1518 | ||
7106e02b PB |
1519 | up_write(&policy->rwsem); |
1520 | ||
d417e069 | 1521 | out_exit_policy: |
da60ce9f VK |
1522 | if (cpufreq_driver->exit) |
1523 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1524 | |
8101f997 | 1525 | out_free_policy: |
f9f41e3e | 1526 | cpufreq_policy_free(policy); |
1da177e4 LT |
1527 | return ret; |
1528 | } | |
1529 | ||
0b275352 RW |
1530 | /** |
1531 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1532 | * @dev: CPU device. | |
1533 | * @sif: Subsystem interface structure pointer (not used) | |
1534 | */ | |
1535 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1536 | { | |
a794d613 | 1537 | struct cpufreq_policy *policy; |
0b275352 | 1538 | unsigned cpu = dev->id; |
26619804 | 1539 | int ret; |
0b275352 RW |
1540 | |
1541 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1542 | ||
26619804 VK |
1543 | if (cpu_online(cpu)) { |
1544 | ret = cpufreq_online(cpu); | |
1545 | if (ret) | |
1546 | return ret; | |
1547 | } | |
0b275352 | 1548 | |
26619804 | 1549 | /* Create sysfs link on CPU registration */ |
a794d613 | 1550 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 RW |
1551 | if (policy) |
1552 | add_cpu_dev_symlink(policy, cpu); | |
26619804 | 1553 | |
2f0ba790 | 1554 | return 0; |
1da177e4 LT |
1555 | } |
1556 | ||
27622b06 | 1557 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1558 | { |
3a3e9e06 | 1559 | struct cpufreq_policy *policy; |
69cee714 | 1560 | int ret; |
1da177e4 | 1561 | |
b8eed8af | 1562 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1563 | |
988bed09 | 1564 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1565 | if (!policy) { |
b8eed8af | 1566 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1567 | return 0; |
1da177e4 | 1568 | } |
1da177e4 | 1569 | |
49f18560 | 1570 | down_write(&policy->rwsem); |
45482c70 RW |
1571 | if (has_target()) |
1572 | cpufreq_stop_governor(policy); | |
1da177e4 | 1573 | |
9591becb | 1574 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1575 | |
9591becb VK |
1576 | if (policy_is_inactive(policy)) { |
1577 | if (has_target()) | |
1578 | strncpy(policy->last_governor, policy->governor->name, | |
1579 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1580 | else |
1581 | policy->last_policy = policy->policy; | |
9591becb VK |
1582 | } else if (cpu == policy->cpu) { |
1583 | /* Nominate new CPU */ | |
1584 | policy->cpu = cpumask_any(policy->cpus); | |
1585 | } | |
084f3493 | 1586 | |
9591becb VK |
1587 | /* Start governor again for active policy */ |
1588 | if (!policy_is_inactive(policy)) { | |
1589 | if (has_target()) { | |
0a300767 | 1590 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1591 | if (ret) |
1592 | pr_err("%s: Failed to start governor\n", __func__); | |
1593 | } | |
cedb70af | 1594 | |
49f18560 | 1595 | goto unlock; |
cedb70af SB |
1596 | } |
1597 | ||
bcc61569 | 1598 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1599 | cpufreq_cooling_unregister(policy->cdev); |
1600 | policy->cdev = NULL; | |
1601 | } | |
1602 | ||
69cee714 VK |
1603 | if (cpufreq_driver->stop_cpu) |
1604 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1605 | |
36be3418 RW |
1606 | if (has_target()) |
1607 | cpufreq_exit_governor(policy); | |
1da177e4 | 1608 | |
87549141 | 1609 | /* |
91a12e91 VK |
1610 | * Perform the ->offline() during light-weight tear-down, as |
1611 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1612 | */ |
91a12e91 VK |
1613 | if (cpufreq_driver->offline) { |
1614 | cpufreq_driver->offline(policy); | |
1615 | } else if (cpufreq_driver->exit) { | |
87549141 | 1616 | cpufreq_driver->exit(policy); |
55582bcc SP |
1617 | policy->freq_table = NULL; |
1618 | } | |
49f18560 VK |
1619 | |
1620 | unlock: | |
1621 | up_write(&policy->rwsem); | |
27622b06 | 1622 | return 0; |
1da177e4 LT |
1623 | } |
1624 | ||
a9909c21 | 1625 | /* |
27a862e9 | 1626 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1627 | * |
1628 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1629 | */ |
71db87ba | 1630 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1631 | { |
8a25a2fd | 1632 | unsigned int cpu = dev->id; |
559ed407 | 1633 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1634 | |
559ed407 | 1635 | if (!policy) |
1af115d6 | 1636 | return; |
87549141 | 1637 | |
69cee714 VK |
1638 | if (cpu_online(cpu)) |
1639 | cpufreq_offline(cpu); | |
87549141 | 1640 | |
559ed407 | 1641 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1642 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1643 | |
91a12e91 VK |
1644 | if (cpumask_empty(policy->real_cpus)) { |
1645 | /* We did light-weight exit earlier, do full tear down now */ | |
1646 | if (cpufreq_driver->offline) | |
1647 | cpufreq_driver->exit(policy); | |
1648 | ||
f9f41e3e | 1649 | cpufreq_policy_free(policy); |
91a12e91 | 1650 | } |
5a01f2e8 VP |
1651 | } |
1652 | ||
1da177e4 | 1653 | /** |
ec06e586 RW |
1654 | * cpufreq_out_of_sync - Fix up actual and saved CPU frequency difference. |
1655 | * @policy: Policy managing CPUs. | |
1656 | * @new_freq: New CPU frequency. | |
1da177e4 | 1657 | * |
ec06e586 RW |
1658 | * Adjust to the current frequency first and clean up later by either calling |
1659 | * cpufreq_update_policy(), or scheduling handle_update(). | |
1da177e4 | 1660 | */ |
a1e1dc41 | 1661 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1662 | unsigned int new_freq) |
1da177e4 LT |
1663 | { |
1664 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1665 | |
e837f9b5 | 1666 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1667 | policy->cur, new_freq); |
1da177e4 | 1668 | |
a1e1dc41 | 1669 | freqs.old = policy->cur; |
1da177e4 | 1670 | freqs.new = new_freq; |
b43a7ffb | 1671 | |
8fec051e VK |
1672 | cpufreq_freq_transition_begin(policy, &freqs); |
1673 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1674 | } |
1675 | ||
5980752e VK |
1676 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1677 | { | |
1678 | unsigned int new_freq; | |
1679 | ||
1680 | new_freq = cpufreq_driver->get(policy->cpu); | |
1681 | if (!new_freq) | |
1682 | return 0; | |
1683 | ||
1684 | /* | |
1685 | * If fast frequency switching is used with the given policy, the check | |
1686 | * against policy->cur is pointless, so skip it in that case. | |
1687 | */ | |
1688 | if (policy->fast_switch_enabled || !has_target()) | |
1689 | return new_freq; | |
1690 | ||
1691 | if (policy->cur != new_freq) { | |
1692 | cpufreq_out_of_sync(policy, new_freq); | |
1693 | if (update) | |
1694 | schedule_work(&policy->update); | |
1695 | } | |
1696 | ||
1697 | return new_freq; | |
1698 | } | |
1699 | ||
32ee8c3e | 1700 | /** |
4ab70df4 | 1701 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1702 | * @cpu: CPU number |
1703 | * | |
1704 | * This is the last known freq, without actually getting it from the driver. | |
1705 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1706 | */ | |
1707 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1708 | { | |
9e21ba8b | 1709 | struct cpufreq_policy *policy; |
e08f5f5b | 1710 | unsigned int ret_freq = 0; |
c75361c0 | 1711 | unsigned long flags; |
95235ca2 | 1712 | |
c75361c0 RC |
1713 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1714 | ||
1715 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1716 | ret_freq = cpufreq_driver->get(cpu); | |
1717 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1718 | return ret_freq; | |
1719 | } | |
1720 | ||
1721 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1722 | |
1723 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1724 | if (policy) { |
e08f5f5b | 1725 | ret_freq = policy->cur; |
95235ca2 VP |
1726 | cpufreq_cpu_put(policy); |
1727 | } | |
1728 | ||
4d34a67d | 1729 | return ret_freq; |
95235ca2 VP |
1730 | } |
1731 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1732 | ||
3d737108 JB |
1733 | /** |
1734 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1735 | * @cpu: CPU number | |
1736 | * | |
1737 | * Just return the max possible frequency for a given CPU. | |
1738 | */ | |
1739 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1740 | { | |
1741 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1742 | unsigned int ret_freq = 0; | |
1743 | ||
1744 | if (policy) { | |
1745 | ret_freq = policy->max; | |
1746 | cpufreq_cpu_put(policy); | |
1747 | } | |
1748 | ||
1749 | return ret_freq; | |
1750 | } | |
1751 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1752 | ||
bbce8eaa IV |
1753 | /** |
1754 | * cpufreq_get_hw_max_freq - get the max hardware frequency of the CPU | |
1755 | * @cpu: CPU number | |
1756 | * | |
1757 | * The default return value is the max_freq field of cpuinfo. | |
1758 | */ | |
1759 | __weak unsigned int cpufreq_get_hw_max_freq(unsigned int cpu) | |
1760 | { | |
1761 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1762 | unsigned int ret_freq = 0; | |
1763 | ||
1764 | if (policy) { | |
1765 | ret_freq = policy->cpuinfo.max_freq; | |
1766 | cpufreq_cpu_put(policy); | |
1767 | } | |
1768 | ||
1769 | return ret_freq; | |
1770 | } | |
1771 | EXPORT_SYMBOL(cpufreq_get_hw_max_freq); | |
1772 | ||
d92d50a4 | 1773 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1774 | { |
4db7c34c | 1775 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1776 | return 0; |
1da177e4 | 1777 | |
5980752e | 1778 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1779 | } |
1da177e4 | 1780 | |
5a01f2e8 VP |
1781 | /** |
1782 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1783 | * @cpu: CPU number | |
1784 | * | |
1785 | * Get the CPU current (static) CPU frequency | |
1786 | */ | |
1787 | unsigned int cpufreq_get(unsigned int cpu) | |
1788 | { | |
999976e0 | 1789 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1790 | unsigned int ret_freq = 0; |
5a01f2e8 | 1791 | |
999976e0 AP |
1792 | if (policy) { |
1793 | down_read(&policy->rwsem); | |
4db7c34c YH |
1794 | if (cpufreq_driver->get) |
1795 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1796 | up_read(&policy->rwsem); |
5a01f2e8 | 1797 | |
999976e0 AP |
1798 | cpufreq_cpu_put(policy); |
1799 | } | |
6eed9404 | 1800 | |
4d34a67d | 1801 | return ret_freq; |
1da177e4 LT |
1802 | } |
1803 | EXPORT_SYMBOL(cpufreq_get); | |
1804 | ||
8a25a2fd KS |
1805 | static struct subsys_interface cpufreq_interface = { |
1806 | .name = "cpufreq", | |
1807 | .subsys = &cpu_subsys, | |
1808 | .add_dev = cpufreq_add_dev, | |
1809 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1810 | }; |
1811 | ||
e28867ea VK |
1812 | /* |
1813 | * In case platform wants some specific frequency to be configured | |
1814 | * during suspend.. | |
1815 | */ | |
1816 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1817 | { | |
1818 | int ret; | |
1819 | ||
1820 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1821 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1822 | return 0; | |
e28867ea VK |
1823 | } |
1824 | ||
1825 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1826 | policy->suspend_freq); | |
1827 | ||
1828 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1829 | CPUFREQ_RELATION_H); | |
1830 | if (ret) | |
1831 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1832 | __func__, policy->suspend_freq, ret); | |
1833 | ||
1834 | return ret; | |
1835 | } | |
1836 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1837 | ||
42d4dc3f | 1838 | /** |
ec06e586 | 1839 | * cpufreq_suspend() - Suspend CPUFreq governors. |
e00e56df | 1840 | * |
2f0aea93 VK |
1841 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1842 | * as some platforms can't change frequency after this point in suspend cycle. | |
1843 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1844 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1845 | */ |
2f0aea93 | 1846 | void cpufreq_suspend(void) |
42d4dc3f | 1847 | { |
3a3e9e06 | 1848 | struct cpufreq_policy *policy; |
42d4dc3f | 1849 | |
2f0aea93 VK |
1850 | if (!cpufreq_driver) |
1851 | return; | |
42d4dc3f | 1852 | |
ba41e1bc | 1853 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1854 | goto suspend; |
42d4dc3f | 1855 | |
2f0aea93 VK |
1856 | pr_debug("%s: Suspending Governors\n", __func__); |
1857 | ||
f963735a | 1858 | for_each_active_policy(policy) { |
ba41e1bc RW |
1859 | if (has_target()) { |
1860 | down_write(&policy->rwsem); | |
45482c70 | 1861 | cpufreq_stop_governor(policy); |
ba41e1bc | 1862 | up_write(&policy->rwsem); |
ba41e1bc RW |
1863 | } |
1864 | ||
1865 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1866 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1867 | cpufreq_driver->name); | |
42d4dc3f | 1868 | } |
b1b12bab VK |
1869 | |
1870 | suspend: | |
1871 | cpufreq_suspended = true; | |
42d4dc3f BH |
1872 | } |
1873 | ||
1da177e4 | 1874 | /** |
ec06e586 | 1875 | * cpufreq_resume() - Resume CPUFreq governors. |
1da177e4 | 1876 | * |
2f0aea93 VK |
1877 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1878 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1879 | */ |
2f0aea93 | 1880 | void cpufreq_resume(void) |
1da177e4 | 1881 | { |
3a3e9e06 | 1882 | struct cpufreq_policy *policy; |
49f18560 | 1883 | int ret; |
1da177e4 | 1884 | |
2f0aea93 | 1885 | if (!cpufreq_driver) |
703cbaa6 BY |
1886 | return; |
1887 | ||
1888 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1889 | return; |
1da177e4 | 1890 | |
8e30444e LT |
1891 | cpufreq_suspended = false; |
1892 | ||
ba41e1bc | 1893 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1894 | return; |
1da177e4 | 1895 | |
2f0aea93 | 1896 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1897 | |
f963735a | 1898 | for_each_active_policy(policy) { |
49f18560 | 1899 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1900 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1901 | policy); | |
ba41e1bc | 1902 | } else if (has_target()) { |
49f18560 | 1903 | down_write(&policy->rwsem); |
0a300767 | 1904 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1905 | up_write(&policy->rwsem); |
1906 | ||
1907 | if (ret) | |
1908 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1909 | __func__, policy); | |
1910 | } | |
2f0aea93 VK |
1911 | } |
1912 | } | |
1da177e4 | 1913 | |
a62f68f5 RW |
1914 | /** |
1915 | * cpufreq_driver_test_flags - Test cpufreq driver's flags against given ones. | |
1916 | * @flags: Flags to test against the current cpufreq driver's flags. | |
1917 | * | |
1918 | * Assumes that the driver is there, so callers must ensure that this is the | |
1919 | * case. | |
1920 | */ | |
1921 | bool cpufreq_driver_test_flags(u16 flags) | |
1922 | { | |
1923 | return !!(cpufreq_driver->flags & flags); | |
1924 | } | |
1925 | ||
9d95046e | 1926 | /** |
ec06e586 | 1927 | * cpufreq_get_current_driver - Return the current driver's name. |
9d95046e | 1928 | * |
ec06e586 RW |
1929 | * Return the name string of the currently registered cpufreq driver or NULL if |
1930 | * none. | |
9d95046e BP |
1931 | */ |
1932 | const char *cpufreq_get_current_driver(void) | |
1933 | { | |
1c3d85dd RW |
1934 | if (cpufreq_driver) |
1935 | return cpufreq_driver->name; | |
1936 | ||
1937 | return NULL; | |
9d95046e BP |
1938 | } |
1939 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1940 | |
51315cdf | 1941 | /** |
ec06e586 | 1942 | * cpufreq_get_driver_data - Return current driver data. |
51315cdf | 1943 | * |
ec06e586 RW |
1944 | * Return the private data of the currently registered cpufreq driver, or NULL |
1945 | * if no cpufreq driver has been registered. | |
51315cdf TP |
1946 | */ |
1947 | void *cpufreq_get_driver_data(void) | |
1948 | { | |
1949 | if (cpufreq_driver) | |
1950 | return cpufreq_driver->driver_data; | |
1951 | ||
1952 | return NULL; | |
1953 | } | |
1954 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1955 | ||
1da177e4 LT |
1956 | /********************************************************************* |
1957 | * NOTIFIER LISTS INTERFACE * | |
1958 | *********************************************************************/ | |
1959 | ||
1960 | /** | |
ec06e586 RW |
1961 | * cpufreq_register_notifier - Register a notifier with cpufreq. |
1962 | * @nb: notifier function to register. | |
1963 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 1964 | * |
ec06e586 RW |
1965 | * Add a notifier to one of two lists: either a list of notifiers that run on |
1966 | * clock rate changes (once before and once after every transition), or a list | |
1967 | * of notifiers that ron on cpufreq policy changes. | |
1da177e4 | 1968 | * |
ec06e586 RW |
1969 | * This function may sleep and it has the same return values as |
1970 | * blocking_notifier_chain_register(). | |
1da177e4 LT |
1971 | */ |
1972 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1973 | { | |
1974 | int ret; | |
1975 | ||
d5aaffa9 DB |
1976 | if (cpufreq_disabled()) |
1977 | return -EINVAL; | |
1978 | ||
1da177e4 LT |
1979 | switch (list) { |
1980 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1981 | mutex_lock(&cpufreq_fast_switch_lock); |
1982 | ||
1983 | if (cpufreq_fast_switch_count > 0) { | |
1984 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1985 | return -EBUSY; | |
1986 | } | |
b4dfdbb3 | 1987 | ret = srcu_notifier_chain_register( |
e041c683 | 1988 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1989 | if (!ret) |
1990 | cpufreq_fast_switch_count--; | |
1991 | ||
1992 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1993 | break; |
1994 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1995 | ret = blocking_notifier_chain_register( |
1996 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1997 | break; |
1998 | default: | |
1999 | ret = -EINVAL; | |
2000 | } | |
1da177e4 LT |
2001 | |
2002 | return ret; | |
2003 | } | |
2004 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
2005 | ||
1da177e4 | 2006 | /** |
ec06e586 RW |
2007 | * cpufreq_unregister_notifier - Unregister a notifier from cpufreq. |
2008 | * @nb: notifier block to be unregistered. | |
2009 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 2010 | * |
ec06e586 | 2011 | * Remove a notifier from one of the cpufreq notifier lists. |
1da177e4 | 2012 | * |
ec06e586 RW |
2013 | * This function may sleep and it has the same return values as |
2014 | * blocking_notifier_chain_unregister(). | |
1da177e4 LT |
2015 | */ |
2016 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
2017 | { | |
2018 | int ret; | |
2019 | ||
d5aaffa9 DB |
2020 | if (cpufreq_disabled()) |
2021 | return -EINVAL; | |
2022 | ||
1da177e4 LT |
2023 | switch (list) { |
2024 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
2025 | mutex_lock(&cpufreq_fast_switch_lock); |
2026 | ||
b4dfdbb3 | 2027 | ret = srcu_notifier_chain_unregister( |
e041c683 | 2028 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2029 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
2030 | cpufreq_fast_switch_count++; | |
2031 | ||
2032 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2033 | break; |
2034 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2035 | ret = blocking_notifier_chain_unregister( |
2036 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2037 | break; |
2038 | default: | |
2039 | ret = -EINVAL; | |
2040 | } | |
1da177e4 LT |
2041 | |
2042 | return ret; | |
2043 | } | |
2044 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
2045 | ||
2046 | ||
2047 | /********************************************************************* | |
2048 | * GOVERNORS * | |
2049 | *********************************************************************/ | |
2050 | ||
b7898fda RW |
2051 | /** |
2052 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
2053 | * @policy: cpufreq policy to switch the frequency for. | |
2054 | * @target_freq: New frequency to set (may be approximate). | |
2055 | * | |
2056 | * Carry out a fast frequency switch without sleeping. | |
2057 | * | |
2058 | * The driver's ->fast_switch() callback invoked by this function must be | |
2059 | * suitable for being called from within RCU-sched read-side critical sections | |
2060 | * and it is expected to select the minimum available frequency greater than or | |
2061 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2062 | * | |
2063 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2064 | * | |
2065 | * Governors calling this function must guarantee that it will never be invoked | |
2066 | * twice in parallel for the same policy and that it will never be called in | |
2067 | * parallel with either ->target() or ->target_index() for the same policy. | |
2068 | * | |
209887e6 VK |
2069 | * Returns the actual frequency set for the CPU. |
2070 | * | |
2071 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2072 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2073 | */ |
2074 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2075 | unsigned int target_freq) | |
2076 | { | |
1a0419b0 | 2077 | unsigned int freq; |
08d8c65e | 2078 | int cpu; |
1a0419b0 | 2079 | |
b9af6948 | 2080 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
1a0419b0 IV |
2081 | freq = cpufreq_driver->fast_switch(policy, target_freq); |
2082 | ||
96f60cdd VK |
2083 | if (!freq) |
2084 | return 0; | |
2085 | ||
08d8c65e | 2086 | policy->cur = freq; |
1a0419b0 IV |
2087 | arch_set_freq_scale(policy->related_cpus, freq, |
2088 | policy->cpuinfo.max_freq); | |
96f60cdd | 2089 | cpufreq_stats_record_transition(policy, freq); |
b7898fda | 2090 | |
08d8c65e VK |
2091 | if (trace_cpu_frequency_enabled()) { |
2092 | for_each_cpu(cpu, policy->cpus) | |
2093 | trace_cpu_frequency(freq, cpu); | |
2094 | } | |
2095 | ||
1a0419b0 | 2096 | return freq; |
b7898fda RW |
2097 | } |
2098 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2099 | ||
ee2cc427 RW |
2100 | /** |
2101 | * cpufreq_driver_adjust_perf - Adjust CPU performance level in one go. | |
2102 | * @cpu: Target CPU. | |
2103 | * @min_perf: Minimum (required) performance level (units of @capacity). | |
2104 | * @target_perf: Terget (desired) performance level (units of @capacity). | |
2105 | * @capacity: Capacity of the target CPU. | |
2106 | * | |
2107 | * Carry out a fast performance level switch of @cpu without sleeping. | |
2108 | * | |
2109 | * The driver's ->adjust_perf() callback invoked by this function must be | |
2110 | * suitable for being called from within RCU-sched read-side critical sections | |
2111 | * and it is expected to select a suitable performance level equal to or above | |
2112 | * @min_perf and preferably equal to or below @target_perf. | |
2113 | * | |
2114 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2115 | * | |
2116 | * Governors calling this function must guarantee that it will never be invoked | |
2117 | * twice in parallel for the same CPU and that it will never be called in | |
2118 | * parallel with either ->target() or ->target_index() or ->fast_switch() for | |
2119 | * the same CPU. | |
2120 | */ | |
2121 | void cpufreq_driver_adjust_perf(unsigned int cpu, | |
2122 | unsigned long min_perf, | |
2123 | unsigned long target_perf, | |
2124 | unsigned long capacity) | |
2125 | { | |
2126 | cpufreq_driver->adjust_perf(cpu, min_perf, target_perf, capacity); | |
2127 | } | |
2128 | ||
2129 | /** | |
2130 | * cpufreq_driver_has_adjust_perf - Check "direct fast switch" callback. | |
2131 | * | |
2132 | * Return 'true' if the ->adjust_perf callback is present for the | |
2133 | * current driver or 'false' otherwise. | |
2134 | */ | |
2135 | bool cpufreq_driver_has_adjust_perf(void) | |
2136 | { | |
2137 | return !!cpufreq_driver->adjust_perf; | |
2138 | } | |
2139 | ||
1c03a2d0 VK |
2140 | /* Must set freqs->new to intermediate frequency */ |
2141 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2142 | struct cpufreq_freqs *freqs, int index) | |
2143 | { | |
2144 | int ret; | |
2145 | ||
2146 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2147 | ||
2148 | /* We don't need to switch to intermediate freq */ | |
2149 | if (!freqs->new) | |
2150 | return 0; | |
2151 | ||
2152 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2153 | __func__, policy->cpu, freqs->old, freqs->new); | |
2154 | ||
2155 | cpufreq_freq_transition_begin(policy, freqs); | |
2156 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2157 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2158 | ||
2159 | if (ret) | |
2160 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2161 | __func__, ret); | |
2162 | ||
2163 | return ret; | |
2164 | } | |
2165 | ||
23727845 | 2166 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2167 | { |
1c03a2d0 | 2168 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
56a7ff75 | 2169 | unsigned int restore_freq, intermediate_freq = 0; |
23727845 | 2170 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2171 | int retval = -EINVAL; |
2172 | bool notify; | |
2173 | ||
23727845 VK |
2174 | if (newfreq == policy->cur) |
2175 | return 0; | |
2176 | ||
56a7ff75 RW |
2177 | /* Save last value to restore later on errors */ |
2178 | restore_freq = policy->cur; | |
2179 | ||
8d65775d | 2180 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2181 | if (notify) { |
1c03a2d0 VK |
2182 | /* Handle switching to intermediate frequency */ |
2183 | if (cpufreq_driver->get_intermediate) { | |
2184 | retval = __target_intermediate(policy, &freqs, index); | |
2185 | if (retval) | |
2186 | return retval; | |
2187 | ||
2188 | intermediate_freq = freqs.new; | |
2189 | /* Set old freq to intermediate */ | |
2190 | if (intermediate_freq) | |
2191 | freqs.old = freqs.new; | |
2192 | } | |
8d65775d | 2193 | |
23727845 | 2194 | freqs.new = newfreq; |
8d65775d VK |
2195 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2196 | __func__, policy->cpu, freqs.old, freqs.new); | |
2197 | ||
2198 | cpufreq_freq_transition_begin(policy, &freqs); | |
2199 | } | |
2200 | ||
2201 | retval = cpufreq_driver->target_index(policy, index); | |
2202 | if (retval) | |
2203 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2204 | retval); | |
2205 | ||
1c03a2d0 | 2206 | if (notify) { |
8d65775d VK |
2207 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2208 | ||
1c03a2d0 VK |
2209 | /* |
2210 | * Failed after setting to intermediate freq? Driver should have | |
2211 | * reverted back to initial frequency and so should we. Check | |
2212 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2213 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2214 | */ |
2215 | if (unlikely(retval && intermediate_freq)) { | |
2216 | freqs.old = intermediate_freq; | |
56a7ff75 | 2217 | freqs.new = restore_freq; |
1c03a2d0 VK |
2218 | cpufreq_freq_transition_begin(policy, &freqs); |
2219 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2220 | } | |
2221 | } | |
2222 | ||
8d65775d VK |
2223 | return retval; |
2224 | } | |
2225 | ||
1da177e4 LT |
2226 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2227 | unsigned int target_freq, | |
2228 | unsigned int relation) | |
2229 | { | |
7249924e | 2230 | unsigned int old_target_freq = target_freq; |
d218ed77 | 2231 | int index; |
c32b6b8e | 2232 | |
a7b422cd KRW |
2233 | if (cpufreq_disabled()) |
2234 | return -ENODEV; | |
2235 | ||
7249924e | 2236 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 2237 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
2238 | |
2239 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2240 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2241 | |
9c0ebcf7 VK |
2242 | /* |
2243 | * This might look like a redundant call as we are checking it again | |
2244 | * after finding index. But it is left intentionally for cases where | |
2245 | * exactly same freq is called again and so we can save on few function | |
2246 | * calls. | |
2247 | */ | |
1c534352 RW |
2248 | if (target_freq == policy->cur && |
2249 | !(cpufreq_driver->flags & CPUFREQ_NEED_UPDATE_LIMITS)) | |
5a1c0228 VK |
2250 | return 0; |
2251 | ||
1c3d85dd | 2252 | if (cpufreq_driver->target) |
6019d23a | 2253 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 2254 | |
6019d23a RW |
2255 | if (!cpufreq_driver->target_index) |
2256 | return -EINVAL; | |
9c0ebcf7 | 2257 | |
d218ed77 | 2258 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 2259 | |
23727845 | 2260 | return __target_index(policy, index); |
1da177e4 LT |
2261 | } |
2262 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2263 | ||
1da177e4 LT |
2264 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2265 | unsigned int target_freq, | |
2266 | unsigned int relation) | |
2267 | { | |
62c23a89 | 2268 | int ret; |
1da177e4 | 2269 | |
ad7722da | 2270 | down_write(&policy->rwsem); |
1da177e4 LT |
2271 | |
2272 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2273 | ||
ad7722da | 2274 | up_write(&policy->rwsem); |
1da177e4 | 2275 | |
1da177e4 LT |
2276 | return ret; |
2277 | } | |
2278 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2279 | ||
de1df26b RW |
2280 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2281 | { | |
2282 | return NULL; | |
2283 | } | |
2284 | ||
a92604b4 | 2285 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2286 | { |
cc993cab | 2287 | int ret; |
6afde10c | 2288 | |
2f0aea93 VK |
2289 | /* Don't start any governor operations if we are entering suspend */ |
2290 | if (cpufreq_suspended) | |
2291 | return 0; | |
cb57720b EZ |
2292 | /* |
2293 | * Governor might not be initiated here if ACPI _PPC changed | |
2294 | * notification happened, so check it. | |
2295 | */ | |
2296 | if (!policy->governor) | |
2297 | return -EINVAL; | |
2f0aea93 | 2298 | |
ed4676e2 | 2299 | /* Platform doesn't want dynamic frequency switching ? */ |
9a2a9ebc | 2300 | if (policy->governor->flags & CPUFREQ_GOV_DYNAMIC_SWITCHING && |
fc4c709f | 2301 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2302 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2303 | ||
2304 | if (gov) { | |
fe829ed8 | 2305 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2306 | policy->governor->name, gov->name); |
6afde10c | 2307 | policy->governor = gov; |
de1df26b RW |
2308 | } else { |
2309 | return -EINVAL; | |
6afde10c | 2310 | } |
1c256245 | 2311 | } |
1da177e4 | 2312 | |
a92604b4 RW |
2313 | if (!try_module_get(policy->governor->owner)) |
2314 | return -EINVAL; | |
95731ebb | 2315 | |
a92604b4 | 2316 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2317 | |
e788892b RW |
2318 | if (policy->governor->init) { |
2319 | ret = policy->governor->init(policy); | |
2320 | if (ret) { | |
36be3418 | 2321 | module_put(policy->governor->owner); |
e788892b RW |
2322 | return ret; |
2323 | } | |
36be3418 | 2324 | } |
1da177e4 | 2325 | |
ea9364bb RW |
2326 | policy->strict_target = !!(policy->governor->flags & CPUFREQ_GOV_STRICT_TARGET); |
2327 | ||
a92604b4 RW |
2328 | return 0; |
2329 | } | |
2330 | ||
2331 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2332 | { | |
2333 | if (cpufreq_suspended || !policy->governor) | |
2334 | return; | |
2335 | ||
2336 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2337 | ||
e788892b RW |
2338 | if (policy->governor->exit) |
2339 | policy->governor->exit(policy); | |
a92604b4 | 2340 | |
a92604b4 | 2341 | module_put(policy->governor->owner); |
1da177e4 LT |
2342 | } |
2343 | ||
f6ebbcf0 | 2344 | int cpufreq_start_governor(struct cpufreq_policy *policy) |
0a300767 RW |
2345 | { |
2346 | int ret; | |
2347 | ||
a92604b4 RW |
2348 | if (cpufreq_suspended) |
2349 | return 0; | |
2350 | ||
2351 | if (!policy->governor) | |
2352 | return -EINVAL; | |
2353 | ||
2354 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2355 | ||
407d0fff | 2356 | if (cpufreq_driver->get) |
5980752e | 2357 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2358 | |
e788892b RW |
2359 | if (policy->governor->start) { |
2360 | ret = policy->governor->start(policy); | |
2361 | if (ret) | |
2362 | return ret; | |
2363 | } | |
2364 | ||
2365 | if (policy->governor->limits) | |
2366 | policy->governor->limits(policy); | |
d6ff44d6 | 2367 | |
d6ff44d6 | 2368 | return 0; |
0a300767 RW |
2369 | } |
2370 | ||
f6ebbcf0 | 2371 | void cpufreq_stop_governor(struct cpufreq_policy *policy) |
a92604b4 RW |
2372 | { |
2373 | if (cpufreq_suspended || !policy->governor) | |
2374 | return; | |
2375 | ||
2376 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2377 | ||
e788892b RW |
2378 | if (policy->governor->stop) |
2379 | policy->governor->stop(policy); | |
a92604b4 RW |
2380 | } |
2381 | ||
2382 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2383 | { | |
2384 | if (cpufreq_suspended || !policy->governor) | |
2385 | return; | |
2386 | ||
2387 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2388 | ||
e788892b RW |
2389 | if (policy->governor->limits) |
2390 | policy->governor->limits(policy); | |
0a300767 RW |
2391 | } |
2392 | ||
1da177e4 LT |
2393 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2394 | { | |
3bcb09a3 | 2395 | int err; |
1da177e4 LT |
2396 | |
2397 | if (!governor) | |
2398 | return -EINVAL; | |
2399 | ||
a7b422cd KRW |
2400 | if (cpufreq_disabled()) |
2401 | return -ENODEV; | |
2402 | ||
3fc54d37 | 2403 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2404 | |
3bcb09a3 | 2405 | err = -EBUSY; |
42f91fa1 | 2406 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2407 | err = 0; |
2408 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2409 | } |
1da177e4 | 2410 | |
32ee8c3e | 2411 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2412 | return err; |
1da177e4 LT |
2413 | } |
2414 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2415 | ||
1da177e4 LT |
2416 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2417 | { | |
4573237b VK |
2418 | struct cpufreq_policy *policy; |
2419 | unsigned long flags; | |
90e41bac | 2420 | |
1da177e4 LT |
2421 | if (!governor) |
2422 | return; | |
2423 | ||
a7b422cd KRW |
2424 | if (cpufreq_disabled()) |
2425 | return; | |
2426 | ||
4573237b VK |
2427 | /* clear last_governor for all inactive policies */ |
2428 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2429 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2430 | if (!strcmp(policy->last_governor, governor->name)) { |
2431 | policy->governor = NULL; | |
4573237b | 2432 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2433 | } |
90e41bac | 2434 | } |
4573237b | 2435 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2436 | |
3fc54d37 | 2437 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2438 | list_del(&governor->governor_list); |
3fc54d37 | 2439 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2440 | } |
2441 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2442 | ||
2443 | ||
1da177e4 LT |
2444 | /********************************************************************* |
2445 | * POLICY INTERFACE * | |
2446 | *********************************************************************/ | |
2447 | ||
2448 | /** | |
2449 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2450 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2451 | * is written | |
a9909c21 | 2452 | * @cpu: CPU to find the policy for |
1da177e4 LT |
2453 | * |
2454 | * Reads the current cpufreq policy. | |
2455 | */ | |
2456 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2457 | { | |
2458 | struct cpufreq_policy *cpu_policy; | |
2459 | if (!policy) | |
2460 | return -EINVAL; | |
2461 | ||
2462 | cpu_policy = cpufreq_cpu_get(cpu); | |
2463 | if (!cpu_policy) | |
2464 | return -EINVAL; | |
2465 | ||
d5b73cd8 | 2466 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2467 | |
2468 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2469 | return 0; |
2470 | } | |
2471 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2472 | ||
a0dbb819 RW |
2473 | /** |
2474 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2475 | * @policy: Policy object to modify. | |
1e4f63ae RW |
2476 | * @new_gov: Policy governor pointer. |
2477 | * @new_pol: Policy value (for drivers with built-in governors). | |
a0dbb819 | 2478 | * |
1e4f63ae RW |
2479 | * Invoke the cpufreq driver's ->verify() callback to sanity-check the frequency |
2480 | * limits to be set for the policy, update @policy with the verified limits | |
2481 | * values and either invoke the driver's ->setpolicy() callback (if present) or | |
2482 | * carry out a governor update for @policy. That is, run the current governor's | |
2483 | * ->limits() callback (if @new_gov points to the same object as the one in | |
2484 | * @policy) or replace the governor for @policy with @new_gov. | |
a0dbb819 RW |
2485 | * |
2486 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2487 | */ |
1e4f63ae RW |
2488 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
2489 | struct cpufreq_governor *new_gov, | |
2490 | unsigned int new_pol) | |
1da177e4 | 2491 | { |
1e4f63ae | 2492 | struct cpufreq_policy_data new_data; |
d9a789c7 RW |
2493 | struct cpufreq_governor *old_gov; |
2494 | int ret; | |
1da177e4 | 2495 | |
1e4f63ae RW |
2496 | memcpy(&new_data.cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
2497 | new_data.freq_table = policy->freq_table; | |
2498 | new_data.cpu = policy->cpu; | |
fba9573b | 2499 | /* |
67d874c3 VK |
2500 | * PM QoS framework collects all the requests from users and provide us |
2501 | * the final aggregated value here. | |
2502 | */ | |
1e4f63ae RW |
2503 | new_data.min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); |
2504 | new_data.max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); | |
2505 | ||
2506 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", | |
2507 | new_data.cpu, new_data.min, new_data.max); | |
9c9a43ed | 2508 | |
737ffb27 VK |
2509 | /* |
2510 | * Verify that the CPU speed can be set within these limits and make sure | |
2511 | * that min <= max. | |
2512 | */ | |
1e4f63ae | 2513 | ret = cpufreq_driver->verify(&new_data); |
1da177e4 | 2514 | if (ret) |
d9a789c7 | 2515 | return ret; |
1da177e4 | 2516 | |
1e4f63ae RW |
2517 | policy->min = new_data.min; |
2518 | policy->max = new_data.max; | |
601b2185 | 2519 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2520 | |
e3c06236 SM |
2521 | policy->cached_target_freq = UINT_MAX; |
2522 | ||
2d06d8c4 | 2523 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2524 | policy->min, policy->max); |
1da177e4 | 2525 | |
1c3d85dd | 2526 | if (cpufreq_driver->setpolicy) { |
1e4f63ae | 2527 | policy->policy = new_pol; |
2d06d8c4 | 2528 | pr_debug("setting range\n"); |
167a38dc | 2529 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2530 | } |
1da177e4 | 2531 | |
1e4f63ae | 2532 | if (new_gov == policy->governor) { |
2bb4059e | 2533 | pr_debug("governor limits update\n"); |
a92604b4 | 2534 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2535 | return 0; |
0a300767 | 2536 | } |
7bd353a9 | 2537 | |
d9a789c7 RW |
2538 | pr_debug("governor switch\n"); |
2539 | ||
2540 | /* save old, working values */ | |
2541 | old_gov = policy->governor; | |
2542 | /* end old governor */ | |
2543 | if (old_gov) { | |
45482c70 | 2544 | cpufreq_stop_governor(policy); |
36be3418 | 2545 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2546 | } |
2547 | ||
d9a789c7 | 2548 | /* start new governor */ |
1e4f63ae | 2549 | policy->governor = new_gov; |
a92604b4 | 2550 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2551 | if (!ret) { |
0a300767 RW |
2552 | ret = cpufreq_start_governor(policy); |
2553 | if (!ret) { | |
2bb4059e | 2554 | pr_debug("governor change\n"); |
531b5c9f | 2555 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2556 | return 0; |
2557 | } | |
b7898fda | 2558 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2559 | } |
2560 | ||
2561 | /* new governor failed, so re-start old one */ | |
2562 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2563 | if (old_gov) { | |
2564 | policy->governor = old_gov; | |
a92604b4 | 2565 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2566 | policy->governor = NULL; |
2567 | else | |
0a300767 | 2568 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2569 | } |
2570 | ||
4bc384ae | 2571 | return ret; |
1da177e4 LT |
2572 | } |
2573 | ||
1da177e4 | 2574 | /** |
a0dbb819 RW |
2575 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2576 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2577 | * |
a0dbb819 | 2578 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2579 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2580 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2581 | * for the policy in question, among other things. | |
1da177e4 | 2582 | */ |
30248fef | 2583 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2584 | { |
540a3758 | 2585 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2586 | |
fefa8ff8 | 2587 | if (!policy) |
30248fef | 2588 | return; |
1da177e4 | 2589 | |
bb176f7d VK |
2590 | /* |
2591 | * BIOS might change freq behind our back | |
2592 | * -> ask driver for current freq and notify governors about a change | |
2593 | */ | |
5ddc6d4e | 2594 | if (cpufreq_driver->get && has_target() && |
5980752e | 2595 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2596 | goto unlock; |
30248fef | 2597 | |
70a59fde | 2598 | refresh_frequency_limits(policy); |
1da177e4 | 2599 | |
fefa8ff8 | 2600 | unlock: |
540a3758 | 2601 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2602 | } |
2603 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2604 | ||
5a25e3f7 RW |
2605 | /** |
2606 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2607 | * @cpu: CPU to update the policy limits for. | |
2608 | * | |
2609 | * Invoke the driver's ->update_limits callback if present or call | |
2610 | * cpufreq_update_policy() for @cpu. | |
2611 | */ | |
2612 | void cpufreq_update_limits(unsigned int cpu) | |
2613 | { | |
2614 | if (cpufreq_driver->update_limits) | |
2615 | cpufreq_driver->update_limits(cpu); | |
2616 | else | |
2617 | cpufreq_update_policy(cpu); | |
2618 | } | |
2619 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2620 | ||
6f19efc0 LM |
2621 | /********************************************************************* |
2622 | * BOOST * | |
2623 | *********************************************************************/ | |
cf6fada7 | 2624 | static int cpufreq_boost_set_sw(struct cpufreq_policy *policy, int state) |
6f19efc0 | 2625 | { |
cf6fada7 | 2626 | int ret; |
49f18560 | 2627 | |
cf6fada7 XW |
2628 | if (!policy->freq_table) |
2629 | return -ENXIO; | |
f8bfc116 | 2630 | |
cf6fada7 XW |
2631 | ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table); |
2632 | if (ret) { | |
2633 | pr_err("%s: Policy frequency update failed\n", __func__); | |
2634 | return ret; | |
6f19efc0 LM |
2635 | } |
2636 | ||
cf6fada7 XW |
2637 | ret = freq_qos_update_request(policy->max_freq_req, policy->max); |
2638 | if (ret < 0) | |
2639 | return ret; | |
2640 | ||
552abb88 | 2641 | return 0; |
6f19efc0 LM |
2642 | } |
2643 | ||
2644 | int cpufreq_boost_trigger_state(int state) | |
2645 | { | |
cf6fada7 | 2646 | struct cpufreq_policy *policy; |
6f19efc0 LM |
2647 | unsigned long flags; |
2648 | int ret = 0; | |
2649 | ||
2650 | if (cpufreq_driver->boost_enabled == state) | |
2651 | return 0; | |
2652 | ||
2653 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2654 | cpufreq_driver->boost_enabled = state; | |
2655 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2656 | ||
cf6fada7 XW |
2657 | get_online_cpus(); |
2658 | for_each_active_policy(policy) { | |
2659 | ret = cpufreq_driver->set_boost(policy, state); | |
2660 | if (ret) | |
2661 | goto err_reset_state; | |
6f19efc0 | 2662 | } |
cf6fada7 XW |
2663 | put_online_cpus(); |
2664 | ||
2665 | return 0; | |
2666 | ||
2667 | err_reset_state: | |
2668 | put_online_cpus(); | |
2669 | ||
2670 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2671 | cpufreq_driver->boost_enabled = !state; | |
2672 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2673 | ||
2674 | pr_err("%s: Cannot %s BOOST\n", | |
2675 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2676 | |
2677 | return ret; | |
2678 | } | |
2679 | ||
41669da0 | 2680 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2681 | { |
89f98d7e | 2682 | return cpufreq_driver->set_boost; |
6f19efc0 | 2683 | } |
6f19efc0 | 2684 | |
44139ed4 VK |
2685 | static int create_boost_sysfs_file(void) |
2686 | { | |
2687 | int ret; | |
2688 | ||
c82bd444 | 2689 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2690 | if (ret) |
2691 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2692 | __func__); | |
2693 | ||
2694 | return ret; | |
2695 | } | |
2696 | ||
2697 | static void remove_boost_sysfs_file(void) | |
2698 | { | |
2699 | if (cpufreq_boost_supported()) | |
c82bd444 | 2700 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2701 | } |
2702 | ||
2703 | int cpufreq_enable_boost_support(void) | |
2704 | { | |
2705 | if (!cpufreq_driver) | |
2706 | return -EINVAL; | |
2707 | ||
2708 | if (cpufreq_boost_supported()) | |
2709 | return 0; | |
2710 | ||
7a6c79f2 | 2711 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2712 | |
2713 | /* This will get removed on driver unregister */ | |
2714 | return create_boost_sysfs_file(); | |
2715 | } | |
2716 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2717 | ||
6f19efc0 LM |
2718 | int cpufreq_boost_enabled(void) |
2719 | { | |
2720 | return cpufreq_driver->boost_enabled; | |
2721 | } | |
2722 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2723 | ||
1da177e4 LT |
2724 | /********************************************************************* |
2725 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2726 | *********************************************************************/ | |
27622b06 | 2727 | static enum cpuhp_state hp_online; |
1da177e4 | 2728 | |
c4a3fa26 CY |
2729 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2730 | { | |
2731 | cpufreq_online(cpu); | |
2732 | ||
2733 | return 0; | |
2734 | } | |
2735 | ||
2736 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2737 | { | |
2738 | cpufreq_offline(cpu); | |
2739 | ||
2740 | return 0; | |
2741 | } | |
2742 | ||
1da177e4 LT |
2743 | /** |
2744 | * cpufreq_register_driver - register a CPU Frequency driver | |
2745 | * @driver_data: A struct cpufreq_driver containing the values# | |
2746 | * submitted by the CPU Frequency driver. | |
2747 | * | |
bb176f7d | 2748 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2749 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2750 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2751 | * |
2752 | */ | |
221dee28 | 2753 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2754 | { |
2755 | unsigned long flags; | |
2756 | int ret; | |
2757 | ||
a7b422cd KRW |
2758 | if (cpufreq_disabled()) |
2759 | return -ENODEV; | |
2760 | ||
46770be0 VK |
2761 | /* |
2762 | * The cpufreq core depends heavily on the availability of device | |
2763 | * structure, make sure they are available before proceeding further. | |
2764 | */ | |
2765 | if (!get_cpu_device(0)) | |
2766 | return -EPROBE_DEFER; | |
2767 | ||
1da177e4 | 2768 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2769 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2770 | driver_data->target) || |
2771 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2772 | driver_data->target)) || |
a9a22b57 | 2773 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2774 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2775 | return -EINVAL; |
2776 | ||
2d06d8c4 | 2777 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2778 | |
fdd320da | 2779 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2780 | cpus_read_lock(); |
fdd320da | 2781 | |
0d1857a1 | 2782 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2783 | if (cpufreq_driver) { |
0d1857a1 | 2784 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2785 | ret = -EEXIST; |
2786 | goto out; | |
1da177e4 | 2787 | } |
1c3d85dd | 2788 | cpufreq_driver = driver_data; |
0d1857a1 | 2789 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2790 | |
874f6353 IV |
2791 | /* |
2792 | * Mark support for the scheduler's frequency invariance engine for | |
2793 | * drivers that implement target(), target_index() or fast_switch(). | |
2794 | */ | |
2795 | if (!cpufreq_driver->setpolicy) { | |
2796 | static_branch_enable_cpuslocked(&cpufreq_freq_invariance); | |
2797 | pr_debug("supports frequency invariance"); | |
2798 | } | |
2799 | ||
bc68b7df VK |
2800 | if (driver_data->setpolicy) |
2801 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2802 | ||
7a6c79f2 RW |
2803 | if (cpufreq_boost_supported()) { |
2804 | ret = create_boost_sysfs_file(); | |
2805 | if (ret) | |
2806 | goto err_null_driver; | |
2807 | } | |
6f19efc0 | 2808 | |
8a25a2fd | 2809 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2810 | if (ret) |
6f19efc0 | 2811 | goto err_boost_unreg; |
1da177e4 | 2812 | |
ce1bcfe9 VK |
2813 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2814 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2815 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2816 | ret = -ENODEV; |
ce1bcfe9 VK |
2817 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2818 | driver_data->name); | |
2819 | goto err_if_unreg; | |
1da177e4 LT |
2820 | } |
2821 | ||
a92551e4 SAS |
2822 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2823 | "cpufreq:online", | |
2824 | cpuhp_cpufreq_online, | |
2825 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2826 | if (ret < 0) |
2827 | goto err_if_unreg; | |
2828 | hp_online = ret; | |
5372e054 | 2829 | ret = 0; |
27622b06 | 2830 | |
2d06d8c4 | 2831 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2832 | goto out; |
fdd320da | 2833 | |
8a25a2fd KS |
2834 | err_if_unreg: |
2835 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2836 | err_boost_unreg: |
44139ed4 | 2837 | remove_boost_sysfs_file(); |
8f5bc2ab | 2838 | err_null_driver: |
0d1857a1 | 2839 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2840 | cpufreq_driver = NULL; |
0d1857a1 | 2841 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2842 | out: |
a92551e4 | 2843 | cpus_read_unlock(); |
3834abb4 | 2844 | return ret; |
1da177e4 LT |
2845 | } |
2846 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2847 | ||
a9909c21 | 2848 | /* |
1da177e4 LT |
2849 | * cpufreq_unregister_driver - unregister the current CPUFreq driver |
2850 | * | |
bb176f7d | 2851 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2852 | * the right to do so, i.e. if you have succeeded in initialising before! |
2853 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2854 | * currently not initialised. | |
2855 | */ | |
221dee28 | 2856 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2857 | { |
2858 | unsigned long flags; | |
2859 | ||
1c3d85dd | 2860 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2861 | return -EINVAL; |
1da177e4 | 2862 | |
2d06d8c4 | 2863 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2864 | |
454d3a25 | 2865 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2866 | cpus_read_lock(); |
8a25a2fd | 2867 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2868 | remove_boost_sysfs_file(); |
874f6353 | 2869 | static_branch_disable_cpuslocked(&cpufreq_freq_invariance); |
a92551e4 | 2870 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2871 | |
0d1857a1 | 2872 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2873 | |
1c3d85dd | 2874 | cpufreq_driver = NULL; |
6eed9404 | 2875 | |
0d1857a1 | 2876 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2877 | cpus_read_unlock(); |
1da177e4 LT |
2878 | |
2879 | return 0; | |
2880 | } | |
2881 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2882 | |
2883 | static int __init cpufreq_core_init(void) | |
2884 | { | |
8412b456 QP |
2885 | struct cpufreq_governor *gov = cpufreq_default_governor(); |
2886 | ||
a7b422cd KRW |
2887 | if (cpufreq_disabled()) |
2888 | return -ENODEV; | |
2889 | ||
8eec1020 | 2890 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2891 | BUG_ON(!cpufreq_global_kobject); |
2892 | ||
8412b456 QP |
2893 | if (!strlen(default_governor)) |
2894 | strncpy(default_governor, gov->name, CPUFREQ_NAME_LEN); | |
2895 | ||
5a01f2e8 VP |
2896 | return 0; |
2897 | } | |
d82f2692 | 2898 | module_param(off, int, 0444); |
8412b456 | 2899 | module_param_string(default_governor, default_governor, CPUFREQ_NAME_LEN, 0444); |
5a01f2e8 | 2900 | core_initcall(cpufreq_core_init); |