Commit | Line | Data |
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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/drivers/cpufreq/cpufreq.c | |
4 | * | |
5 | * Copyright (C) 2001 Russell King | |
6 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 7 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 8 | * |
c32b6b8e | 9 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 10 | * Added handling for CPU hotplug |
8ff69732 DJ |
11 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
12 | * Fix handling for CPU hotplug -- affected CPUs | |
1da177e4 LT |
13 | */ |
14 | ||
db701151 VK |
15 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
16 | ||
5ff0a268 | 17 | #include <linux/cpu.h> |
1da177e4 | 18 | #include <linux/cpufreq.h> |
5c238a8b | 19 | #include <linux/cpu_cooling.h> |
1da177e4 | 20 | #include <linux/delay.h> |
1da177e4 | 21 | #include <linux/device.h> |
5ff0a268 VK |
22 | #include <linux/init.h> |
23 | #include <linux/kernel_stat.h> | |
24 | #include <linux/module.h> | |
3fc54d37 | 25 | #include <linux/mutex.h> |
67d874c3 | 26 | #include <linux/pm_qos.h> |
5ff0a268 | 27 | #include <linux/slab.h> |
2f0aea93 | 28 | #include <linux/suspend.h> |
90de2a4a | 29 | #include <linux/syscore_ops.h> |
5ff0a268 | 30 | #include <linux/tick.h> |
f55ae08c | 31 | #include <linux/units.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
b4f0676f | 34 | static LIST_HEAD(cpufreq_policy_list); |
f963735a | 35 | |
f963735a | 36 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
37 | #define for_each_suitable_policy(__policy, __active) \ |
38 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
39 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
40 | |
41 | #define for_each_active_policy(__policy) \ | |
42 | for_each_suitable_policy(__policy, true) | |
43 | #define for_each_inactive_policy(__policy) \ | |
44 | for_each_suitable_policy(__policy, false) | |
45 | ||
f7b27061 VK |
46 | /* Iterate over governors */ |
47 | static LIST_HEAD(cpufreq_governor_list); | |
48 | #define for_each_governor(__governor) \ | |
49 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
50 | ||
8412b456 QP |
51 | static char default_governor[CPUFREQ_NAME_LEN]; |
52 | ||
a9909c21 | 53 | /* |
cd878479 | 54 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
55 | * level driver of CPUFreq support, and its spinlock. This lock |
56 | * also protects the cpufreq_cpu_data array. | |
57 | */ | |
1c3d85dd | 58 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 59 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 60 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 61 | |
874f6353 IV |
62 | static DEFINE_STATIC_KEY_FALSE(cpufreq_freq_invariance); |
63 | bool cpufreq_supports_freq_invariance(void) | |
64 | { | |
65 | return static_branch_likely(&cpufreq_freq_invariance); | |
66 | } | |
67 | ||
2f0aea93 VK |
68 | /* Flag to suspend/resume CPUFreq governors */ |
69 | static bool cpufreq_suspended; | |
1da177e4 | 70 | |
9c0ebcf7 VK |
71 | static inline bool has_target(void) |
72 | { | |
73 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
74 | } | |
75 | ||
1da177e4 | 76 | /* internal prototypes */ |
d92d50a4 | 77 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
78 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
79 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
a92604b4 | 80 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); |
1e4f63ae RW |
81 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
82 | struct cpufreq_governor *new_gov, | |
83 | unsigned int new_pol); | |
45482c70 | 84 | |
a9909c21 | 85 | /* |
32ee8c3e DJ |
86 | * Two notifier lists: the "policy" list is involved in the |
87 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
88 | * "transition" list for kernel code that needs to handle |
89 | * changes to devices when the CPU clock speed changes. | |
90 | * The mutex locks both lists. | |
91 | */ | |
e041c683 | 92 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 93 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 94 | |
a7b422cd | 95 | static int off __read_mostly; |
da584455 | 96 | static int cpufreq_disabled(void) |
a7b422cd KRW |
97 | { |
98 | return off; | |
99 | } | |
100 | void disable_cpufreq(void) | |
101 | { | |
102 | off = 1; | |
103 | } | |
29464f28 | 104 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 105 | |
4d5dcc42 VK |
106 | bool have_governor_per_policy(void) |
107 | { | |
0b981e70 | 108 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 109 | } |
3f869d6d | 110 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 111 | |
183edb20 YL |
112 | static struct kobject *cpufreq_global_kobject; |
113 | ||
944e9a03 VK |
114 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
115 | { | |
116 | if (have_governor_per_policy()) | |
117 | return &policy->kobj; | |
118 | else | |
119 | return cpufreq_global_kobject; | |
120 | } | |
121 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
122 | ||
72a4ce34 VK |
123 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
124 | { | |
5720821b | 125 | struct kernel_cpustat kcpustat; |
72a4ce34 | 126 | u64 cur_wall_time; |
5720821b | 127 | u64 idle_time; |
72a4ce34 VK |
128 | u64 busy_time; |
129 | ||
7fb1327e | 130 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 | 131 | |
5720821b FW |
132 | kcpustat_cpu_fetch(&kcpustat, cpu); |
133 | ||
134 | busy_time = kcpustat.cpustat[CPUTIME_USER]; | |
135 | busy_time += kcpustat.cpustat[CPUTIME_SYSTEM]; | |
136 | busy_time += kcpustat.cpustat[CPUTIME_IRQ]; | |
137 | busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ]; | |
138 | busy_time += kcpustat.cpustat[CPUTIME_STEAL]; | |
139 | busy_time += kcpustat.cpustat[CPUTIME_NICE]; | |
72a4ce34 VK |
140 | |
141 | idle_time = cur_wall_time - busy_time; | |
142 | if (wall) | |
7fb1327e | 143 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 144 | |
7fb1327e | 145 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
146 | } |
147 | ||
148 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
149 | { | |
150 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
151 | ||
152 | if (idle_time == -1ULL) | |
153 | return get_cpu_idle_time_jiffy(cpu, wall); | |
154 | else if (!io_busy) | |
155 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
156 | ||
157 | return idle_time; | |
158 | } | |
159 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
160 | ||
70e9e778 VK |
161 | /* |
162 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
163 | * drivers of SMP systems. It will do following: | |
164 | * - validate & show freq table passed | |
165 | * - set policies transition latency | |
166 | * - policy->cpus with all possible CPUs | |
167 | */ | |
c4dcc8a1 | 168 | void cpufreq_generic_init(struct cpufreq_policy *policy, |
70e9e778 VK |
169 | struct cpufreq_frequency_table *table, |
170 | unsigned int transition_latency) | |
171 | { | |
92c99d15 | 172 | policy->freq_table = table; |
70e9e778 VK |
173 | policy->cpuinfo.transition_latency = transition_latency; |
174 | ||
175 | /* | |
58405af6 | 176 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
177 | * share the clock and voltage and clock. |
178 | */ | |
179 | cpumask_setall(policy->cpus); | |
70e9e778 VK |
180 | } |
181 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
182 | ||
1f0bd44e | 183 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
184 | { |
185 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
186 | ||
988bed09 VK |
187 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
188 | } | |
1f0bd44e | 189 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
190 | |
191 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
192 | { | |
193 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
194 | ||
652ed95d | 195 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
196 | pr_err("%s: No %s associated to cpu: %d\n", |
197 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
198 | return 0; |
199 | } | |
200 | ||
201 | return clk_get_rate(policy->clk) / 1000; | |
202 | } | |
203 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
204 | ||
50e9c852 | 205 | /** |
5d094fea RW |
206 | * cpufreq_cpu_get - Return policy for a CPU and mark it as busy. |
207 | * @cpu: CPU to find the policy for. | |
50e9c852 | 208 | * |
5d094fea RW |
209 | * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment |
210 | * the kobject reference counter of that policy. Return a valid policy on | |
211 | * success or NULL on failure. | |
50e9c852 | 212 | * |
5d094fea RW |
213 | * The policy returned by this function has to be released with the help of |
214 | * cpufreq_cpu_put() to balance its kobject reference counter properly. | |
50e9c852 | 215 | */ |
6eed9404 | 216 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 217 | { |
6eed9404 | 218 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
219 | unsigned long flags; |
220 | ||
1b947c90 | 221 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
222 | return NULL; |
223 | ||
1da177e4 | 224 | /* get the cpufreq driver */ |
1c3d85dd | 225 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 226 | |
6eed9404 VK |
227 | if (cpufreq_driver) { |
228 | /* get the CPU */ | |
988bed09 | 229 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
230 | if (policy) |
231 | kobject_get(&policy->kobj); | |
232 | } | |
1da177e4 | 233 | |
6eed9404 | 234 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 235 | |
3a3e9e06 | 236 | return policy; |
a9144436 | 237 | } |
1da177e4 LT |
238 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
239 | ||
50e9c852 | 240 | /** |
5d094fea RW |
241 | * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy. |
242 | * @policy: cpufreq policy returned by cpufreq_cpu_get(). | |
50e9c852 | 243 | */ |
3a3e9e06 | 244 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 245 | { |
6eed9404 | 246 | kobject_put(&policy->kobj); |
1da177e4 LT |
247 | } |
248 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
249 | ||
540a3758 RW |
250 | /** |
251 | * cpufreq_cpu_release - Unlock a policy and decrement its usage counter. | |
252 | * @policy: cpufreq policy returned by cpufreq_cpu_acquire(). | |
253 | */ | |
9083e498 | 254 | void cpufreq_cpu_release(struct cpufreq_policy *policy) |
540a3758 RW |
255 | { |
256 | if (WARN_ON(!policy)) | |
257 | return; | |
258 | ||
259 | lockdep_assert_held(&policy->rwsem); | |
260 | ||
261 | up_write(&policy->rwsem); | |
262 | ||
263 | cpufreq_cpu_put(policy); | |
264 | } | |
265 | ||
266 | /** | |
267 | * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it. | |
268 | * @cpu: CPU to find the policy for. | |
269 | * | |
270 | * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and | |
271 | * if the policy returned by it is not NULL, acquire its rwsem for writing. | |
272 | * Return the policy if it is active or release it and return NULL otherwise. | |
273 | * | |
274 | * The policy returned by this function has to be released with the help of | |
275 | * cpufreq_cpu_release() in order to release its rwsem and balance its usage | |
276 | * counter properly. | |
277 | */ | |
9083e498 | 278 | struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) |
540a3758 RW |
279 | { |
280 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
281 | ||
282 | if (!policy) | |
283 | return NULL; | |
284 | ||
285 | down_write(&policy->rwsem); | |
286 | ||
287 | if (policy_is_inactive(policy)) { | |
288 | cpufreq_cpu_release(policy); | |
289 | return NULL; | |
290 | } | |
291 | ||
292 | return policy; | |
293 | } | |
294 | ||
1da177e4 LT |
295 | /********************************************************************* |
296 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
297 | *********************************************************************/ | |
298 | ||
ec06e586 RW |
299 | /** |
300 | * adjust_jiffies - Adjust the system "loops_per_jiffy". | |
301 | * @val: CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
302 | * @ci: Frequency change information. | |
1da177e4 LT |
303 | * |
304 | * This function alters the system "loops_per_jiffy" for the clock | |
305 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 306 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
307 | * per-CPU loops_per_jiffy value wherever possible. |
308 | */ | |
858119e1 | 309 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 310 | { |
39c132ee VK |
311 | #ifndef CONFIG_SMP |
312 | static unsigned long l_p_j_ref; | |
313 | static unsigned int l_p_j_ref_freq; | |
314 | ||
1da177e4 LT |
315 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
316 | return; | |
317 | ||
318 | if (!l_p_j_ref_freq) { | |
319 | l_p_j_ref = loops_per_jiffy; | |
320 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
321 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
322 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 323 | } |
0b443ead | 324 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
325 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
326 | ci->new); | |
e837f9b5 JP |
327 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
328 | loops_per_jiffy, ci->new); | |
1da177e4 | 329 | } |
1da177e4 | 330 | #endif |
39c132ee | 331 | } |
1da177e4 | 332 | |
20b5324d | 333 | /** |
ec06e586 | 334 | * cpufreq_notify_transition - Notify frequency transition and adjust jiffies. |
20b5324d VK |
335 | * @policy: cpufreq policy to enable fast frequency switching for. |
336 | * @freqs: contain details of the frequency update. | |
337 | * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
338 | * | |
ec06e586 RW |
339 | * This function calls the transition notifiers and adjust_jiffies(). |
340 | * | |
341 | * It is called twice on all CPU frequency changes that have external effects. | |
20b5324d VK |
342 | */ |
343 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
344 | struct cpufreq_freqs *freqs, | |
345 | unsigned int state) | |
1da177e4 | 346 | { |
df24014a VK |
347 | int cpu; |
348 | ||
1da177e4 LT |
349 | BUG_ON(irqs_disabled()); |
350 | ||
d5aaffa9 DB |
351 | if (cpufreq_disabled()) |
352 | return; | |
353 | ||
df24014a | 354 | freqs->policy = policy; |
1c3d85dd | 355 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 356 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 357 | state, freqs->new); |
1da177e4 | 358 | |
1da177e4 LT |
359 | switch (state) { |
360 | case CPUFREQ_PRECHANGE: | |
20b5324d VK |
361 | /* |
362 | * Detect if the driver reported a value as "old frequency" | |
e4472cb3 DJ |
363 | * which is not equal to what the cpufreq core thinks is |
364 | * "old frequency". | |
1da177e4 | 365 | */ |
98015228 VK |
366 | if (policy->cur && policy->cur != freqs->old) { |
367 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", | |
368 | freqs->old, policy->cur); | |
369 | freqs->old = policy->cur; | |
1da177e4 | 370 | } |
20b5324d | 371 | |
df24014a VK |
372 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
373 | CPUFREQ_PRECHANGE, freqs); | |
20b5324d | 374 | |
1da177e4 LT |
375 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
376 | break; | |
e4472cb3 | 377 | |
1da177e4 LT |
378 | case CPUFREQ_POSTCHANGE: |
379 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
20b5324d VK |
380 | pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, |
381 | cpumask_pr_args(policy->cpus)); | |
382 | ||
df24014a VK |
383 | for_each_cpu(cpu, policy->cpus) |
384 | trace_cpu_frequency(freqs->new, cpu); | |
385 | ||
386 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, | |
387 | CPUFREQ_POSTCHANGE, freqs); | |
20b5324d | 388 | |
1aefc75b | 389 | cpufreq_stats_record_transition(policy, freqs->new); |
20b5324d | 390 | policy->cur = freqs->new; |
1da177e4 | 391 | } |
1da177e4 | 392 | } |
bb176f7d | 393 | |
f7ba3b41 | 394 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 395 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
396 | struct cpufreq_freqs *freqs, int transition_failed) |
397 | { | |
398 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
399 | if (!transition_failed) | |
400 | return; | |
401 | ||
402 | swap(freqs->old, freqs->new); | |
403 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
404 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
405 | } | |
f7ba3b41 | 406 | |
12478cf0 SB |
407 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
408 | struct cpufreq_freqs *freqs) | |
409 | { | |
ca654dc3 SB |
410 | |
411 | /* | |
412 | * Catch double invocations of _begin() which lead to self-deadlock. | |
413 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
414 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
415 | * double invocations are very low. Moreover, there are scenarios | |
416 | * where these checks can emit false-positive warnings in these | |
417 | * drivers; so we avoid that by skipping them altogether. | |
418 | */ | |
419 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
420 | && current == policy->transition_task); | |
421 | ||
12478cf0 SB |
422 | wait: |
423 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
424 | ||
425 | spin_lock(&policy->transition_lock); | |
426 | ||
427 | if (unlikely(policy->transition_ongoing)) { | |
428 | spin_unlock(&policy->transition_lock); | |
429 | goto wait; | |
430 | } | |
431 | ||
432 | policy->transition_ongoing = true; | |
ca654dc3 | 433 | policy->transition_task = current; |
12478cf0 SB |
434 | |
435 | spin_unlock(&policy->transition_lock); | |
436 | ||
437 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
438 | } | |
439 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
440 | ||
441 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
442 | struct cpufreq_freqs *freqs, int transition_failed) | |
443 | { | |
0e7ea2f3 | 444 | if (WARN_ON(!policy->transition_ongoing)) |
12478cf0 SB |
445 | return; |
446 | ||
447 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
448 | ||
1a0419b0 IV |
449 | arch_set_freq_scale(policy->related_cpus, |
450 | policy->cur, | |
451 | policy->cpuinfo.max_freq); | |
452 | ||
12478cf0 | 453 | policy->transition_ongoing = false; |
ca654dc3 | 454 | policy->transition_task = NULL; |
12478cf0 SB |
455 | |
456 | wake_up(&policy->transition_wait); | |
457 | } | |
458 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
459 | ||
b7898fda RW |
460 | /* |
461 | * Fast frequency switching status count. Positive means "enabled", negative | |
462 | * means "disabled" and 0 means "not decided yet". | |
463 | */ | |
464 | static int cpufreq_fast_switch_count; | |
465 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
466 | ||
467 | static void cpufreq_list_transition_notifiers(void) | |
468 | { | |
469 | struct notifier_block *nb; | |
470 | ||
471 | pr_info("Registered transition notifiers:\n"); | |
472 | ||
473 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
474 | ||
475 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
d75f773c | 476 | pr_info("%pS\n", nb->notifier_call); |
b7898fda RW |
477 | |
478 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
479 | } | |
480 | ||
481 | /** | |
482 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
483 | * @policy: cpufreq policy to enable fast frequency switching for. | |
484 | * | |
485 | * Try to enable fast frequency switching for @policy. | |
486 | * | |
487 | * The attempt will fail if there is at least one transition notifier registered | |
488 | * at this point, as fast frequency switching is quite fundamentally at odds | |
489 | * with transition notifiers. Thus if successful, it will make registration of | |
490 | * transition notifiers fail going forward. | |
491 | */ | |
492 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
493 | { | |
494 | lockdep_assert_held(&policy->rwsem); | |
495 | ||
496 | if (!policy->fast_switch_possible) | |
497 | return; | |
498 | ||
499 | mutex_lock(&cpufreq_fast_switch_lock); | |
500 | if (cpufreq_fast_switch_count >= 0) { | |
501 | cpufreq_fast_switch_count++; | |
502 | policy->fast_switch_enabled = true; | |
503 | } else { | |
504 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
505 | policy->cpu); | |
506 | cpufreq_list_transition_notifiers(); | |
507 | } | |
508 | mutex_unlock(&cpufreq_fast_switch_lock); | |
509 | } | |
510 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
511 | ||
6c9d9c81 RW |
512 | /** |
513 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
514 | * @policy: cpufreq policy to disable fast frequency switching for. | |
515 | */ | |
516 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
517 | { |
518 | mutex_lock(&cpufreq_fast_switch_lock); | |
519 | if (policy->fast_switch_enabled) { | |
520 | policy->fast_switch_enabled = false; | |
521 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
522 | cpufreq_fast_switch_count--; | |
523 | } | |
524 | mutex_unlock(&cpufreq_fast_switch_lock); | |
525 | } | |
6c9d9c81 | 526 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 527 | |
f9ccdec2 VK |
528 | static unsigned int __resolve_freq(struct cpufreq_policy *policy, |
529 | unsigned int target_freq, unsigned int relation) | |
e3c06236 | 530 | { |
b3beca76 | 531 | unsigned int idx; |
abe8bd02 | 532 | |
b3beca76 | 533 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
abe8bd02 | 534 | |
b3beca76 VK |
535 | if (!cpufreq_driver->target_index) |
536 | return target_freq; | |
abe8bd02 | 537 | |
b3beca76 VK |
538 | idx = cpufreq_frequency_table_target(policy, target_freq, relation); |
539 | policy->cached_resolved_idx = idx; | |
540 | policy->cached_target_freq = target_freq; | |
541 | return policy->freq_table[idx].frequency; | |
e3c06236 | 542 | } |
f9ccdec2 VK |
543 | |
544 | /** | |
545 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
546 | * one. | |
547 | * @policy: associated policy to interrogate | |
548 | * @target_freq: target frequency to resolve. | |
549 | * | |
550 | * The target to driver frequency mapping is cached in the policy. | |
551 | * | |
552 | * Return: Lowest driver-supported frequency greater than or equal to the | |
553 | * given target_freq, subject to policy (min/max) and driver limitations. | |
554 | */ | |
555 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
556 | unsigned int target_freq) | |
557 | { | |
b894d20e | 558 | return __resolve_freq(policy, target_freq, CPUFREQ_RELATION_LE); |
f9ccdec2 | 559 | } |
ae2c1ca6 | 560 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 561 | |
aa7519af VK |
562 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
563 | { | |
564 | unsigned int latency; | |
565 | ||
566 | if (policy->transition_delay_us) | |
567 | return policy->transition_delay_us; | |
568 | ||
569 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
570 | if (latency) { |
571 | /* | |
572 | * For platforms that can change the frequency very fast (< 10 | |
573 | * us), the above formula gives a decent transition delay. But | |
574 | * for platforms where transition_latency is in milliseconds, it | |
575 | * ends up giving unrealistic values. | |
576 | * | |
577 | * Cap the default transition delay to 10 ms, which seems to be | |
578 | * a reasonable amount of time after which we should reevaluate | |
579 | * the frequency. | |
580 | */ | |
581 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
582 | } | |
aa7519af VK |
583 | |
584 | return LATENCY_MULTIPLIER; | |
585 | } | |
586 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
587 | ||
1da177e4 LT |
588 | /********************************************************************* |
589 | * SYSFS INTERFACE * | |
590 | *********************************************************************/ | |
8a5c74a1 | 591 | static ssize_t show_boost(struct kobject *kobj, |
625c85a6 | 592 | struct kobj_attribute *attr, char *buf) |
6f19efc0 LM |
593 | { |
594 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
595 | } | |
596 | ||
625c85a6 VK |
597 | static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, |
598 | const char *buf, size_t count) | |
6f19efc0 LM |
599 | { |
600 | int ret, enable; | |
601 | ||
602 | ret = sscanf(buf, "%d", &enable); | |
603 | if (ret != 1 || enable < 0 || enable > 1) | |
604 | return -EINVAL; | |
605 | ||
606 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
607 | pr_err("%s: Cannot %s BOOST!\n", |
608 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
609 | return -EINVAL; |
610 | } | |
611 | ||
e837f9b5 JP |
612 | pr_debug("%s: cpufreq BOOST %s\n", |
613 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
614 | |
615 | return count; | |
616 | } | |
617 | define_one_global_rw(boost); | |
1da177e4 | 618 | |
42f91fa1 | 619 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
620 | { |
621 | struct cpufreq_governor *t; | |
622 | ||
f7b27061 | 623 | for_each_governor(t) |
7c4f4539 | 624 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
625 | return t; |
626 | ||
627 | return NULL; | |
628 | } | |
629 | ||
8cc46ae5 VK |
630 | static struct cpufreq_governor *get_governor(const char *str_governor) |
631 | { | |
632 | struct cpufreq_governor *t; | |
633 | ||
634 | mutex_lock(&cpufreq_governor_mutex); | |
635 | t = find_governor(str_governor); | |
636 | if (!t) | |
637 | goto unlock; | |
638 | ||
639 | if (!try_module_get(t->owner)) | |
640 | t = NULL; | |
641 | ||
642 | unlock: | |
643 | mutex_unlock(&cpufreq_governor_mutex); | |
644 | ||
645 | return t; | |
646 | } | |
647 | ||
1e4f63ae | 648 | static unsigned int cpufreq_parse_policy(char *str_governor) |
ab05d97a | 649 | { |
1e4f63ae RW |
650 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) |
651 | return CPUFREQ_POLICY_PERFORMANCE; | |
652 | ||
653 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) | |
654 | return CPUFREQ_POLICY_POWERSAVE; | |
655 | ||
656 | return CPUFREQ_POLICY_UNKNOWN; | |
ab05d97a YH |
657 | } |
658 | ||
1da177e4 | 659 | /** |
5ddc6d4e | 660 | * cpufreq_parse_governor - parse a governor string only for has_target() |
1e4f63ae | 661 | * @str_governor: Governor name. |
1da177e4 | 662 | */ |
1e4f63ae | 663 | static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor) |
1da177e4 | 664 | { |
ab05d97a | 665 | struct cpufreq_governor *t; |
045149e6 | 666 | |
8cc46ae5 VK |
667 | t = get_governor(str_governor); |
668 | if (t) | |
669 | return t; | |
ea714970 | 670 | |
8cc46ae5 VK |
671 | if (request_module("cpufreq_%s", str_governor)) |
672 | return NULL; | |
045149e6 | 673 | |
8cc46ae5 | 674 | return get_governor(str_governor); |
1da177e4 | 675 | } |
1da177e4 | 676 | |
a9909c21 | 677 | /* |
e08f5f5b GS |
678 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
679 | * print out cpufreq information | |
1da177e4 LT |
680 | * |
681 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
682 | * "unsigned int". | |
683 | */ | |
684 | ||
32ee8c3e DJ |
685 | #define show_one(file_name, object) \ |
686 | static ssize_t show_##file_name \ | |
905d77cd | 687 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 688 | { \ |
29464f28 | 689 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
690 | } |
691 | ||
692 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
693 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 694 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
695 | show_one(scaling_min_freq, min); |
696 | show_one(scaling_max_freq, max); | |
c034b02e | 697 | |
f8475cef LB |
698 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
699 | { | |
700 | return 0; | |
701 | } | |
702 | ||
09347b29 | 703 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
704 | { |
705 | ssize_t ret; | |
f8475cef | 706 | unsigned int freq; |
c034b02e | 707 | |
f8475cef LB |
708 | freq = arch_freq_get_on_cpu(policy->cpu); |
709 | if (freq) | |
710 | ret = sprintf(buf, "%u\n", freq); | |
681fe684 | 711 | else if (cpufreq_driver->setpolicy && cpufreq_driver->get) |
c034b02e DB |
712 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
713 | else | |
714 | ret = sprintf(buf, "%u\n", policy->cur); | |
715 | return ret; | |
716 | } | |
1da177e4 | 717 | |
a9909c21 | 718 | /* |
1da177e4 LT |
719 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access |
720 | */ | |
721 | #define store_one(file_name, object) \ | |
722 | static ssize_t store_##file_name \ | |
905d77cd | 723 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 724 | { \ |
18c49926 VK |
725 | unsigned long val; \ |
726 | int ret; \ | |
1da177e4 | 727 | \ |
18c49926 | 728 | ret = sscanf(buf, "%lu", &val); \ |
1da177e4 LT |
729 | if (ret != 1) \ |
730 | return -EINVAL; \ | |
731 | \ | |
3000ce3c | 732 | ret = freq_qos_update_request(policy->object##_freq_req, val);\ |
18c49926 | 733 | return ret >= 0 ? count : ret; \ |
1da177e4 LT |
734 | } |
735 | ||
29464f28 DJ |
736 | store_one(scaling_min_freq, min); |
737 | store_one(scaling_max_freq, max); | |
1da177e4 | 738 | |
a9909c21 | 739 | /* |
1da177e4 LT |
740 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware |
741 | */ | |
905d77cd DJ |
742 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
743 | char *buf) | |
1da177e4 | 744 | { |
d92d50a4 | 745 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
746 | |
747 | if (cur_freq) | |
748 | return sprintf(buf, "%u\n", cur_freq); | |
749 | ||
750 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
751 | } |
752 | ||
a9909c21 | 753 | /* |
1da177e4 LT |
754 | * show_scaling_governor - show the current policy for the specified CPU |
755 | */ | |
905d77cd | 756 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 757 | { |
29464f28 | 758 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
759 | return sprintf(buf, "powersave\n"); |
760 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
761 | return sprintf(buf, "performance\n"); | |
762 | else if (policy->governor) | |
4b972f0b | 763 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 764 | policy->governor->name); |
1da177e4 LT |
765 | return -EINVAL; |
766 | } | |
767 | ||
a9909c21 | 768 | /* |
1da177e4 LT |
769 | * store_scaling_governor - store policy for the specified CPU |
770 | */ | |
905d77cd DJ |
771 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
772 | const char *buf, size_t count) | |
1da177e4 | 773 | { |
1e4f63ae | 774 | char str_governor[16]; |
5136fa56 | 775 | int ret; |
1da177e4 | 776 | |
29464f28 | 777 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
778 | if (ret != 1) |
779 | return -EINVAL; | |
780 | ||
ab05d97a | 781 | if (cpufreq_driver->setpolicy) { |
1e4f63ae RW |
782 | unsigned int new_pol; |
783 | ||
784 | new_pol = cpufreq_parse_policy(str_governor); | |
785 | if (!new_pol) | |
ab05d97a | 786 | return -EINVAL; |
1e4f63ae RW |
787 | |
788 | ret = cpufreq_set_policy(policy, NULL, new_pol); | |
ab05d97a | 789 | } else { |
1e4f63ae RW |
790 | struct cpufreq_governor *new_gov; |
791 | ||
792 | new_gov = cpufreq_parse_governor(str_governor); | |
793 | if (!new_gov) | |
ab05d97a | 794 | return -EINVAL; |
1da177e4 | 795 | |
1e4f63ae RW |
796 | ret = cpufreq_set_policy(policy, new_gov, |
797 | CPUFREQ_POLICY_UNKNOWN); | |
a8b149d3 | 798 | |
1e4f63ae RW |
799 | module_put(new_gov->owner); |
800 | } | |
a8b149d3 | 801 | |
88dc4384 | 802 | return ret ? ret : count; |
1da177e4 LT |
803 | } |
804 | ||
a9909c21 | 805 | /* |
1da177e4 LT |
806 | * show_scaling_driver - show the cpufreq driver currently loaded |
807 | */ | |
905d77cd | 808 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 809 | { |
1c3d85dd | 810 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
811 | } |
812 | ||
a9909c21 | 813 | /* |
1da177e4 LT |
814 | * show_scaling_available_governors - show the available CPUfreq governors |
815 | */ | |
905d77cd DJ |
816 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
817 | char *buf) | |
1da177e4 LT |
818 | { |
819 | ssize_t i = 0; | |
820 | struct cpufreq_governor *t; | |
821 | ||
9c0ebcf7 | 822 | if (!has_target()) { |
1da177e4 LT |
823 | i += sprintf(buf, "performance powersave"); |
824 | goto out; | |
825 | } | |
826 | ||
8cc46ae5 | 827 | mutex_lock(&cpufreq_governor_mutex); |
f7b27061 | 828 | for_each_governor(t) { |
29464f28 DJ |
829 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
830 | - (CPUFREQ_NAME_LEN + 2))) | |
8cc46ae5 | 831 | break; |
4b972f0b | 832 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 833 | } |
8cc46ae5 | 834 | mutex_unlock(&cpufreq_governor_mutex); |
7d5e350f | 835 | out: |
1da177e4 LT |
836 | i += sprintf(&buf[i], "\n"); |
837 | return i; | |
838 | } | |
e8628dd0 | 839 | |
f4fd3797 | 840 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
841 | { |
842 | ssize_t i = 0; | |
843 | unsigned int cpu; | |
844 | ||
835481d9 | 845 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
846 | if (i) |
847 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
848 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
849 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 850 | break; |
1da177e4 LT |
851 | } |
852 | i += sprintf(&buf[i], "\n"); | |
853 | return i; | |
854 | } | |
f4fd3797 | 855 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 856 | |
a9909c21 | 857 | /* |
e8628dd0 DW |
858 | * show_related_cpus - show the CPUs affected by each transition even if |
859 | * hw coordination is in use | |
860 | */ | |
861 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
862 | { | |
f4fd3797 | 863 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
864 | } |
865 | ||
a9909c21 | 866 | /* |
e8628dd0 DW |
867 | * show_affected_cpus - show the CPUs affected by each transition |
868 | */ | |
869 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
870 | { | |
f4fd3797 | 871 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
872 | } |
873 | ||
9e76988e | 874 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 875 | const char *buf, size_t count) |
9e76988e VP |
876 | { |
877 | unsigned int freq = 0; | |
878 | unsigned int ret; | |
879 | ||
879000f9 | 880 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
881 | return -EINVAL; |
882 | ||
883 | ret = sscanf(buf, "%u", &freq); | |
884 | if (ret != 1) | |
885 | return -EINVAL; | |
886 | ||
887 | policy->governor->store_setspeed(policy, freq); | |
888 | ||
889 | return count; | |
890 | } | |
891 | ||
892 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
893 | { | |
879000f9 | 894 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
895 | return sprintf(buf, "<unsupported>\n"); |
896 | ||
897 | return policy->governor->show_setspeed(policy, buf); | |
898 | } | |
1da177e4 | 899 | |
a9909c21 | 900 | /* |
8bf1ac72 | 901 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
902 | */ |
903 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
904 | { | |
905 | unsigned int limit; | |
906 | int ret; | |
b23aa311 YH |
907 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
908 | if (!ret) | |
909 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
910 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
911 | } | |
912 | ||
6dad2a29 BP |
913 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
914 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
915 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
916 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
917 | cpufreq_freq_attr_ro(scaling_available_governors); | |
918 | cpufreq_freq_attr_ro(scaling_driver); | |
919 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
920 | cpufreq_freq_attr_ro(bios_limit); | |
921 | cpufreq_freq_attr_ro(related_cpus); | |
922 | cpufreq_freq_attr_ro(affected_cpus); | |
923 | cpufreq_freq_attr_rw(scaling_min_freq); | |
924 | cpufreq_freq_attr_rw(scaling_max_freq); | |
925 | cpufreq_freq_attr_rw(scaling_governor); | |
926 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 927 | |
fe262d5c | 928 | static struct attribute *cpufreq_attrs[] = { |
1da177e4 LT |
929 | &cpuinfo_min_freq.attr, |
930 | &cpuinfo_max_freq.attr, | |
ed129784 | 931 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
932 | &scaling_min_freq.attr, |
933 | &scaling_max_freq.attr, | |
934 | &affected_cpus.attr, | |
e8628dd0 | 935 | &related_cpus.attr, |
1da177e4 LT |
936 | &scaling_governor.attr, |
937 | &scaling_driver.attr, | |
938 | &scaling_available_governors.attr, | |
9e76988e | 939 | &scaling_setspeed.attr, |
1da177e4 LT |
940 | NULL |
941 | }; | |
fe262d5c | 942 | ATTRIBUTE_GROUPS(cpufreq); |
1da177e4 | 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, | |
fe262d5c | 1005 | .default_groups = cpufreq_groups, |
1da177e4 LT |
1006 | .release = cpufreq_sysfs_release, |
1007 | }; | |
1008 | ||
2c1b5a84 XW |
1009 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu, |
1010 | struct device *dev) | |
87549141 | 1011 | { |
67d874c3 | 1012 | if (unlikely(!dev)) |
2f0ba790 RW |
1013 | return; |
1014 | ||
1015 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
1016 | return; | |
1017 | ||
26619804 | 1018 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
1019 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
1020 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
1021 | } |
1022 | ||
5c84c1b8 | 1023 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu, |
26619804 | 1024 | struct device *dev) |
87549141 | 1025 | { |
26619804 VK |
1026 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1027 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
5c84c1b8 | 1028 | cpumask_clear_cpu(cpu, policy->real_cpus); |
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 | /* | |
1e81d3e0 TY |
1301 | * Remove max_freq_req after sending CPUFREQ_REMOVE_POLICY |
1302 | * notification, since CPUFREQ_CREATE_POLICY notification was | |
1303 | * sent after adding max_freq_req earlier. | |
6a149036 VK |
1304 | */ |
1305 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1306 | CPUFREQ_REMOVE_POLICY, policy); | |
3000ce3c | 1307 | freq_qos_remove_request(policy->max_freq_req); |
6a149036 VK |
1308 | } |
1309 | ||
3000ce3c | 1310 | freq_qos_remove_request(policy->min_freq_req); |
18c49926 | 1311 | kfree(policy->min_freq_req); |
67d874c3 | 1312 | |
f9f41e3e | 1313 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1314 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1315 | free_cpumask_var(policy->related_cpus); |
1316 | free_cpumask_var(policy->cpus); | |
1317 | kfree(policy); | |
1318 | } | |
1319 | ||
0b275352 | 1320 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1321 | { |
7f0c020a | 1322 | struct cpufreq_policy *policy; |
194d99c7 | 1323 | bool new_policy; |
1da177e4 | 1324 | unsigned long flags; |
0b275352 RW |
1325 | unsigned int j; |
1326 | int ret; | |
87549141 | 1327 | |
0b275352 | 1328 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1329 | |
bb29ae15 | 1330 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1331 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1332 | if (policy) { |
9104bb26 | 1333 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1334 | if (!policy_is_inactive(policy)) |
d9612a49 | 1335 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1336 | |
11ce707e | 1337 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1338 | new_policy = false; |
11ce707e RW |
1339 | down_write(&policy->rwsem); |
1340 | policy->cpu = cpu; | |
1341 | policy->governor = NULL; | |
1342 | up_write(&policy->rwsem); | |
1343 | } else { | |
194d99c7 | 1344 | new_policy = true; |
a34e63b1 | 1345 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1346 | if (!policy) |
d4d854d6 | 1347 | return -ENOMEM; |
72368d12 | 1348 | } |
0d66b91e | 1349 | |
91a12e91 VK |
1350 | if (!new_policy && cpufreq_driver->online) { |
1351 | ret = cpufreq_driver->online(policy); | |
1352 | if (ret) { | |
1353 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1354 | __LINE__); | |
1355 | goto out_exit_policy; | |
1356 | } | |
1da177e4 | 1357 | |
91a12e91 VK |
1358 | /* Recover policy->cpus using related_cpus */ |
1359 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1360 | } else { | |
1361 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1362 | |
91a12e91 VK |
1363 | /* |
1364 | * Call driver. From then on the cpufreq must be able | |
1365 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1366 | */ | |
1367 | ret = cpufreq_driver->init(policy); | |
1368 | if (ret) { | |
1369 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1370 | __LINE__); | |
1371 | goto out_free_policy; | |
1372 | } | |
d417e069 | 1373 | |
3b718057 RW |
1374 | /* |
1375 | * The initialization has succeeded and the policy is online. | |
1376 | * If there is a problem with its frequency table, take it | |
1377 | * offline and drop it. | |
1378 | */ | |
91a12e91 VK |
1379 | ret = cpufreq_table_validate_and_sort(policy); |
1380 | if (ret) | |
3b718057 | 1381 | goto out_offline_policy; |
6d4e81ed | 1382 | |
4d1f3a5b | 1383 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1384 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1385 | } |
559ed407 | 1386 | |
91a12e91 | 1387 | down_write(&policy->rwsem); |
5a7e56a5 VK |
1388 | /* |
1389 | * affected cpus must always be the one, which are online. We aren't | |
1390 | * managing offline cpus here. | |
1391 | */ | |
1392 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1393 | ||
194d99c7 | 1394 | if (new_policy) { |
2f0ba790 | 1395 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1396 | per_cpu(cpufreq_cpu_data, j) = policy; |
2c1b5a84 | 1397 | add_cpu_dev_symlink(policy, j, get_cpu_device(j)); |
2f0ba790 | 1398 | } |
18c49926 VK |
1399 | |
1400 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1401 | GFP_KERNEL); | |
b96f0384 WS |
1402 | if (!policy->min_freq_req) { |
1403 | ret = -ENOMEM; | |
18c49926 | 1404 | goto out_destroy_policy; |
b96f0384 | 1405 | } |
18c49926 | 1406 | |
3000ce3c RW |
1407 | ret = freq_qos_add_request(&policy->constraints, |
1408 | policy->min_freq_req, FREQ_QOS_MIN, | |
521223d8 | 1409 | FREQ_QOS_MIN_DEFAULT_VALUE); |
18c49926 VK |
1410 | if (ret < 0) { |
1411 | /* | |
3000ce3c | 1412 | * So we don't call freq_qos_remove_request() for an |
18c49926 VK |
1413 | * uninitialized request. |
1414 | */ | |
1415 | kfree(policy->min_freq_req); | |
1416 | policy->min_freq_req = NULL; | |
18c49926 VK |
1417 | goto out_destroy_policy; |
1418 | } | |
1419 | ||
1420 | /* | |
1421 | * This must be initialized right here to avoid calling | |
3000ce3c | 1422 | * freq_qos_remove_request() on uninitialized request in case |
18c49926 VK |
1423 | * of errors. |
1424 | */ | |
1425 | policy->max_freq_req = policy->min_freq_req + 1; | |
1426 | ||
3000ce3c RW |
1427 | ret = freq_qos_add_request(&policy->constraints, |
1428 | policy->max_freq_req, FREQ_QOS_MAX, | |
521223d8 | 1429 | FREQ_QOS_MAX_DEFAULT_VALUE); |
18c49926 VK |
1430 | if (ret < 0) { |
1431 | policy->max_freq_req = NULL; | |
18c49926 VK |
1432 | goto out_destroy_policy; |
1433 | } | |
6a149036 VK |
1434 | |
1435 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1436 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1437 | } |
652ed95d | 1438 | |
5ddc6d4e | 1439 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1440 | policy->cur = cpufreq_driver->get(policy->cpu); |
1441 | if (!policy->cur) { | |
b96f0384 | 1442 | ret = -EIO; |
da60ce9f | 1443 | pr_err("%s: ->get() failed\n", __func__); |
d417e069 | 1444 | goto out_destroy_policy; |
da60ce9f VK |
1445 | } |
1446 | } | |
1447 | ||
d3916691 VK |
1448 | /* |
1449 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1450 | * frequency table present with cpufreq core. In such cases CPU might be | |
1451 | * unstable if it has to run on that frequency for long duration of time | |
1452 | * and so its better to set it to a frequency which is specified in | |
1453 | * freq-table. This also makes cpufreq stats inconsistent as | |
1454 | * cpufreq-stats would fail to register because current frequency of CPU | |
1455 | * isn't found in freq-table. | |
1456 | * | |
1457 | * Because we don't want this change to effect boot process badly, we go | |
1458 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1459 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1460 | * is initialized to zero). | |
1461 | * | |
1462 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1463 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1464 | * equal to target-freq. | |
1465 | */ | |
1466 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1467 | && has_target()) { | |
97148d0a VK |
1468 | unsigned int old_freq = policy->cur; |
1469 | ||
d3916691 | 1470 | /* Are we running at unknown frequency ? */ |
97148d0a | 1471 | ret = cpufreq_frequency_table_get_index(policy, old_freq); |
d3916691 | 1472 | if (ret == -EINVAL) { |
97148d0a VK |
1473 | ret = __cpufreq_driver_target(policy, old_freq - 1, |
1474 | CPUFREQ_RELATION_L); | |
d3916691 VK |
1475 | |
1476 | /* | |
1477 | * Reaching here after boot in a few seconds may not | |
1478 | * mean that system will remain stable at "unknown" | |
1479 | * frequency for longer duration. Hence, a BUG_ON(). | |
1480 | */ | |
1481 | BUG_ON(ret); | |
97148d0a VK |
1482 | pr_info("%s: CPU%d: Running at unlisted initial frequency: %u KHz, changing to: %u KHz\n", |
1483 | __func__, policy->cpu, old_freq, policy->cur); | |
d3916691 VK |
1484 | } |
1485 | } | |
1486 | ||
194d99c7 | 1487 | if (new_policy) { |
d9612a49 | 1488 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1489 | if (ret) |
d417e069 | 1490 | goto out_destroy_policy; |
1aefc75b RW |
1491 | |
1492 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1493 | |
988bed09 VK |
1494 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1495 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1496 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
c17495b0 VK |
1497 | |
1498 | /* | |
1499 | * Register with the energy model before | |
1500 | * sched_cpufreq_governor_change() is called, which will result | |
1501 | * in rebuilding of the sched domains, which should only be done | |
1502 | * once the energy model is properly initialized for the policy | |
1503 | * first. | |
1504 | * | |
1505 | * Also, this should be called before the policy is registered | |
1506 | * with cooling framework. | |
1507 | */ | |
1508 | if (cpufreq_driver->register_em) | |
1509 | cpufreq_driver->register_em(policy); | |
988bed09 | 1510 | } |
9515f4d6 | 1511 | |
7f0fa40f VK |
1512 | ret = cpufreq_init_policy(policy); |
1513 | if (ret) { | |
1514 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1515 | __func__, cpu, ret); | |
d417e069 | 1516 | goto out_destroy_policy; |
08fd8c1c | 1517 | } |
e18f1682 | 1518 | |
4e97b631 | 1519 | up_write(&policy->rwsem); |
08fd8c1c | 1520 | |
038c5b3e | 1521 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1522 | |
4f774c4a BA |
1523 | /* Callback for handling stuff after policy is ready */ |
1524 | if (cpufreq_driver->ready) | |
1525 | cpufreq_driver->ready(policy); | |
1526 | ||
bcc61569 | 1527 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1528 | policy->cdev = of_cpufreq_cooling_register(policy); |
1529 | ||
2d06d8c4 | 1530 | pr_debug("initialization complete\n"); |
87c32271 | 1531 | |
1da177e4 LT |
1532 | return 0; |
1533 | ||
d417e069 | 1534 | out_destroy_policy: |
b24b6478 | 1535 | for_each_cpu(j, policy->real_cpus) |
5c84c1b8 | 1536 | remove_cpu_dev_symlink(policy, j, get_cpu_device(j)); |
b24b6478 | 1537 | |
85f0e42b VK |
1538 | up_write(&policy->rwsem); |
1539 | ||
3b718057 RW |
1540 | out_offline_policy: |
1541 | if (cpufreq_driver->offline) | |
1542 | cpufreq_driver->offline(policy); | |
1543 | ||
d417e069 | 1544 | out_exit_policy: |
da60ce9f VK |
1545 | if (cpufreq_driver->exit) |
1546 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1547 | |
8101f997 | 1548 | out_free_policy: |
f9f41e3e | 1549 | cpufreq_policy_free(policy); |
1da177e4 LT |
1550 | return ret; |
1551 | } | |
1552 | ||
0b275352 RW |
1553 | /** |
1554 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1555 | * @dev: CPU device. | |
1556 | * @sif: Subsystem interface structure pointer (not used) | |
1557 | */ | |
1558 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1559 | { | |
a794d613 | 1560 | struct cpufreq_policy *policy; |
0b275352 | 1561 | unsigned cpu = dev->id; |
26619804 | 1562 | int ret; |
0b275352 RW |
1563 | |
1564 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1565 | ||
26619804 VK |
1566 | if (cpu_online(cpu)) { |
1567 | ret = cpufreq_online(cpu); | |
1568 | if (ret) | |
1569 | return ret; | |
1570 | } | |
0b275352 | 1571 | |
26619804 | 1572 | /* Create sysfs link on CPU registration */ |
a794d613 | 1573 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 | 1574 | if (policy) |
2c1b5a84 | 1575 | add_cpu_dev_symlink(policy, cpu, dev); |
26619804 | 1576 | |
2f0ba790 | 1577 | return 0; |
1da177e4 LT |
1578 | } |
1579 | ||
27622b06 | 1580 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1581 | { |
3a3e9e06 | 1582 | struct cpufreq_policy *policy; |
69cee714 | 1583 | int ret; |
1da177e4 | 1584 | |
b8eed8af | 1585 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1586 | |
988bed09 | 1587 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1588 | if (!policy) { |
b8eed8af | 1589 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1590 | return 0; |
1da177e4 | 1591 | } |
1da177e4 | 1592 | |
49f18560 | 1593 | down_write(&policy->rwsem); |
45482c70 RW |
1594 | if (has_target()) |
1595 | cpufreq_stop_governor(policy); | |
1da177e4 | 1596 | |
9591becb | 1597 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1598 | |
9591becb VK |
1599 | if (policy_is_inactive(policy)) { |
1600 | if (has_target()) | |
1601 | strncpy(policy->last_governor, policy->governor->name, | |
1602 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1603 | else |
1604 | policy->last_policy = policy->policy; | |
9591becb VK |
1605 | } else if (cpu == policy->cpu) { |
1606 | /* Nominate new CPU */ | |
1607 | policy->cpu = cpumask_any(policy->cpus); | |
1608 | } | |
084f3493 | 1609 | |
9591becb VK |
1610 | /* Start governor again for active policy */ |
1611 | if (!policy_is_inactive(policy)) { | |
1612 | if (has_target()) { | |
0a300767 | 1613 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1614 | if (ret) |
1615 | pr_err("%s: Failed to start governor\n", __func__); | |
1616 | } | |
cedb70af | 1617 | |
49f18560 | 1618 | goto unlock; |
cedb70af SB |
1619 | } |
1620 | ||
bcc61569 | 1621 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1622 | cpufreq_cooling_unregister(policy->cdev); |
1623 | policy->cdev = NULL; | |
1624 | } | |
1625 | ||
36be3418 RW |
1626 | if (has_target()) |
1627 | cpufreq_exit_governor(policy); | |
1da177e4 | 1628 | |
87549141 | 1629 | /* |
91a12e91 VK |
1630 | * Perform the ->offline() during light-weight tear-down, as |
1631 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1632 | */ |
91a12e91 VK |
1633 | if (cpufreq_driver->offline) { |
1634 | cpufreq_driver->offline(policy); | |
1635 | } else if (cpufreq_driver->exit) { | |
87549141 | 1636 | cpufreq_driver->exit(policy); |
55582bcc SP |
1637 | policy->freq_table = NULL; |
1638 | } | |
49f18560 VK |
1639 | |
1640 | unlock: | |
1641 | up_write(&policy->rwsem); | |
27622b06 | 1642 | return 0; |
1da177e4 LT |
1643 | } |
1644 | ||
a9909c21 | 1645 | /* |
27a862e9 | 1646 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1647 | * |
1648 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1649 | */ |
71db87ba | 1650 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1651 | { |
8a25a2fd | 1652 | unsigned int cpu = dev->id; |
559ed407 | 1653 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1654 | |
559ed407 | 1655 | if (!policy) |
1af115d6 | 1656 | return; |
87549141 | 1657 | |
69cee714 VK |
1658 | if (cpu_online(cpu)) |
1659 | cpufreq_offline(cpu); | |
87549141 | 1660 | |
5c84c1b8 | 1661 | remove_cpu_dev_symlink(policy, cpu, dev); |
87549141 | 1662 | |
91a12e91 VK |
1663 | if (cpumask_empty(policy->real_cpus)) { |
1664 | /* We did light-weight exit earlier, do full tear down now */ | |
1665 | if (cpufreq_driver->offline) | |
1666 | cpufreq_driver->exit(policy); | |
1667 | ||
f9f41e3e | 1668 | cpufreq_policy_free(policy); |
91a12e91 | 1669 | } |
5a01f2e8 VP |
1670 | } |
1671 | ||
1da177e4 | 1672 | /** |
ec06e586 RW |
1673 | * cpufreq_out_of_sync - Fix up actual and saved CPU frequency difference. |
1674 | * @policy: Policy managing CPUs. | |
1675 | * @new_freq: New CPU frequency. | |
1da177e4 | 1676 | * |
ec06e586 RW |
1677 | * Adjust to the current frequency first and clean up later by either calling |
1678 | * cpufreq_update_policy(), or scheduling handle_update(). | |
1da177e4 | 1679 | */ |
a1e1dc41 | 1680 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1681 | unsigned int new_freq) |
1da177e4 LT |
1682 | { |
1683 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1684 | |
e837f9b5 | 1685 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1686 | policy->cur, new_freq); |
1da177e4 | 1687 | |
a1e1dc41 | 1688 | freqs.old = policy->cur; |
1da177e4 | 1689 | freqs.new = new_freq; |
b43a7ffb | 1690 | |
8fec051e VK |
1691 | cpufreq_freq_transition_begin(policy, &freqs); |
1692 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1693 | } |
1694 | ||
5980752e VK |
1695 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1696 | { | |
1697 | unsigned int new_freq; | |
1698 | ||
1699 | new_freq = cpufreq_driver->get(policy->cpu); | |
1700 | if (!new_freq) | |
1701 | return 0; | |
1702 | ||
1703 | /* | |
1704 | * If fast frequency switching is used with the given policy, the check | |
1705 | * against policy->cur is pointless, so skip it in that case. | |
1706 | */ | |
1707 | if (policy->fast_switch_enabled || !has_target()) | |
1708 | return new_freq; | |
1709 | ||
1710 | if (policy->cur != new_freq) { | |
f55ae08c VK |
1711 | /* |
1712 | * For some platforms, the frequency returned by hardware may be | |
1713 | * slightly different from what is provided in the frequency | |
1714 | * table, for example hardware may return 499 MHz instead of 500 | |
1715 | * MHz. In such cases it is better to avoid getting into | |
1716 | * unnecessary frequency updates. | |
1717 | */ | |
1718 | if (abs(policy->cur - new_freq) < HZ_PER_MHZ) | |
1719 | return policy->cur; | |
1720 | ||
5980752e VK |
1721 | cpufreq_out_of_sync(policy, new_freq); |
1722 | if (update) | |
1723 | schedule_work(&policy->update); | |
1724 | } | |
1725 | ||
1726 | return new_freq; | |
1727 | } | |
1728 | ||
32ee8c3e | 1729 | /** |
4ab70df4 | 1730 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1731 | * @cpu: CPU number |
1732 | * | |
1733 | * This is the last known freq, without actually getting it from the driver. | |
1734 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1735 | */ | |
1736 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1737 | { | |
9e21ba8b | 1738 | struct cpufreq_policy *policy; |
e08f5f5b | 1739 | unsigned int ret_freq = 0; |
c75361c0 | 1740 | unsigned long flags; |
95235ca2 | 1741 | |
c75361c0 RC |
1742 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1743 | ||
1744 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1745 | ret_freq = cpufreq_driver->get(cpu); | |
1746 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1747 | return ret_freq; | |
1748 | } | |
1749 | ||
1750 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1751 | |
1752 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1753 | if (policy) { |
e08f5f5b | 1754 | ret_freq = policy->cur; |
95235ca2 VP |
1755 | cpufreq_cpu_put(policy); |
1756 | } | |
1757 | ||
4d34a67d | 1758 | return ret_freq; |
95235ca2 VP |
1759 | } |
1760 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1761 | ||
3d737108 JB |
1762 | /** |
1763 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1764 | * @cpu: CPU number | |
1765 | * | |
1766 | * Just return the max possible frequency for a given CPU. | |
1767 | */ | |
1768 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1769 | { | |
1770 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1771 | unsigned int ret_freq = 0; | |
1772 | ||
1773 | if (policy) { | |
1774 | ret_freq = policy->max; | |
1775 | cpufreq_cpu_put(policy); | |
1776 | } | |
1777 | ||
1778 | return ret_freq; | |
1779 | } | |
1780 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1781 | ||
bbce8eaa IV |
1782 | /** |
1783 | * cpufreq_get_hw_max_freq - get the max hardware frequency of the CPU | |
1784 | * @cpu: CPU number | |
1785 | * | |
1786 | * The default return value is the max_freq field of cpuinfo. | |
1787 | */ | |
1788 | __weak unsigned int cpufreq_get_hw_max_freq(unsigned int cpu) | |
1789 | { | |
1790 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1791 | unsigned int ret_freq = 0; | |
1792 | ||
1793 | if (policy) { | |
1794 | ret_freq = policy->cpuinfo.max_freq; | |
1795 | cpufreq_cpu_put(policy); | |
1796 | } | |
1797 | ||
1798 | return ret_freq; | |
1799 | } | |
1800 | EXPORT_SYMBOL(cpufreq_get_hw_max_freq); | |
1801 | ||
d92d50a4 | 1802 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1803 | { |
4db7c34c | 1804 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1805 | return 0; |
1da177e4 | 1806 | |
5980752e | 1807 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1808 | } |
1da177e4 | 1809 | |
5a01f2e8 VP |
1810 | /** |
1811 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1812 | * @cpu: CPU number | |
1813 | * | |
1814 | * Get the CPU current (static) CPU frequency | |
1815 | */ | |
1816 | unsigned int cpufreq_get(unsigned int cpu) | |
1817 | { | |
999976e0 | 1818 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1819 | unsigned int ret_freq = 0; |
5a01f2e8 | 1820 | |
999976e0 AP |
1821 | if (policy) { |
1822 | down_read(&policy->rwsem); | |
4db7c34c YH |
1823 | if (cpufreq_driver->get) |
1824 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1825 | up_read(&policy->rwsem); |
5a01f2e8 | 1826 | |
999976e0 AP |
1827 | cpufreq_cpu_put(policy); |
1828 | } | |
6eed9404 | 1829 | |
4d34a67d | 1830 | return ret_freq; |
1da177e4 LT |
1831 | } |
1832 | EXPORT_SYMBOL(cpufreq_get); | |
1833 | ||
8a25a2fd KS |
1834 | static struct subsys_interface cpufreq_interface = { |
1835 | .name = "cpufreq", | |
1836 | .subsys = &cpu_subsys, | |
1837 | .add_dev = cpufreq_add_dev, | |
1838 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1839 | }; |
1840 | ||
e28867ea VK |
1841 | /* |
1842 | * In case platform wants some specific frequency to be configured | |
1843 | * during suspend.. | |
1844 | */ | |
1845 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1846 | { | |
1847 | int ret; | |
1848 | ||
1849 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1850 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1851 | return 0; | |
e28867ea VK |
1852 | } |
1853 | ||
1854 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1855 | policy->suspend_freq); | |
1856 | ||
1857 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1858 | CPUFREQ_RELATION_H); | |
1859 | if (ret) | |
1860 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1861 | __func__, policy->suspend_freq, ret); | |
1862 | ||
1863 | return ret; | |
1864 | } | |
1865 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1866 | ||
42d4dc3f | 1867 | /** |
ec06e586 | 1868 | * cpufreq_suspend() - Suspend CPUFreq governors. |
e00e56df | 1869 | * |
2f0aea93 VK |
1870 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1871 | * as some platforms can't change frequency after this point in suspend cycle. | |
1872 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1873 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1874 | */ |
2f0aea93 | 1875 | void cpufreq_suspend(void) |
42d4dc3f | 1876 | { |
3a3e9e06 | 1877 | struct cpufreq_policy *policy; |
42d4dc3f | 1878 | |
2f0aea93 VK |
1879 | if (!cpufreq_driver) |
1880 | return; | |
42d4dc3f | 1881 | |
ba41e1bc | 1882 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1883 | goto suspend; |
42d4dc3f | 1884 | |
2f0aea93 VK |
1885 | pr_debug("%s: Suspending Governors\n", __func__); |
1886 | ||
f963735a | 1887 | for_each_active_policy(policy) { |
ba41e1bc RW |
1888 | if (has_target()) { |
1889 | down_write(&policy->rwsem); | |
45482c70 | 1890 | cpufreq_stop_governor(policy); |
ba41e1bc | 1891 | up_write(&policy->rwsem); |
ba41e1bc RW |
1892 | } |
1893 | ||
1894 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1895 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1896 | cpufreq_driver->name); | |
42d4dc3f | 1897 | } |
b1b12bab VK |
1898 | |
1899 | suspend: | |
1900 | cpufreq_suspended = true; | |
42d4dc3f BH |
1901 | } |
1902 | ||
1da177e4 | 1903 | /** |
ec06e586 | 1904 | * cpufreq_resume() - Resume CPUFreq governors. |
1da177e4 | 1905 | * |
2f0aea93 VK |
1906 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1907 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1908 | */ |
2f0aea93 | 1909 | void cpufreq_resume(void) |
1da177e4 | 1910 | { |
3a3e9e06 | 1911 | struct cpufreq_policy *policy; |
49f18560 | 1912 | int ret; |
1da177e4 | 1913 | |
2f0aea93 | 1914 | if (!cpufreq_driver) |
703cbaa6 BY |
1915 | return; |
1916 | ||
1917 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1918 | return; |
1da177e4 | 1919 | |
8e30444e LT |
1920 | cpufreq_suspended = false; |
1921 | ||
ba41e1bc | 1922 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1923 | return; |
1da177e4 | 1924 | |
2f0aea93 | 1925 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1926 | |
f963735a | 1927 | for_each_active_policy(policy) { |
49f18560 | 1928 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1929 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1930 | policy); | |
ba41e1bc | 1931 | } else if (has_target()) { |
49f18560 | 1932 | down_write(&policy->rwsem); |
0a300767 | 1933 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1934 | up_write(&policy->rwsem); |
1935 | ||
1936 | if (ret) | |
1937 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1938 | __func__, policy); | |
1939 | } | |
2f0aea93 VK |
1940 | } |
1941 | } | |
1da177e4 | 1942 | |
a62f68f5 RW |
1943 | /** |
1944 | * cpufreq_driver_test_flags - Test cpufreq driver's flags against given ones. | |
1945 | * @flags: Flags to test against the current cpufreq driver's flags. | |
1946 | * | |
1947 | * Assumes that the driver is there, so callers must ensure that this is the | |
1948 | * case. | |
1949 | */ | |
1950 | bool cpufreq_driver_test_flags(u16 flags) | |
1951 | { | |
1952 | return !!(cpufreq_driver->flags & flags); | |
1953 | } | |
1954 | ||
9d95046e | 1955 | /** |
ec06e586 | 1956 | * cpufreq_get_current_driver - Return the current driver's name. |
9d95046e | 1957 | * |
ec06e586 RW |
1958 | * Return the name string of the currently registered cpufreq driver or NULL if |
1959 | * none. | |
9d95046e BP |
1960 | */ |
1961 | const char *cpufreq_get_current_driver(void) | |
1962 | { | |
1c3d85dd RW |
1963 | if (cpufreq_driver) |
1964 | return cpufreq_driver->name; | |
1965 | ||
1966 | return NULL; | |
9d95046e BP |
1967 | } |
1968 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1969 | |
51315cdf | 1970 | /** |
ec06e586 | 1971 | * cpufreq_get_driver_data - Return current driver data. |
51315cdf | 1972 | * |
ec06e586 RW |
1973 | * Return the private data of the currently registered cpufreq driver, or NULL |
1974 | * if no cpufreq driver has been registered. | |
51315cdf TP |
1975 | */ |
1976 | void *cpufreq_get_driver_data(void) | |
1977 | { | |
1978 | if (cpufreq_driver) | |
1979 | return cpufreq_driver->driver_data; | |
1980 | ||
1981 | return NULL; | |
1982 | } | |
1983 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1984 | ||
1da177e4 LT |
1985 | /********************************************************************* |
1986 | * NOTIFIER LISTS INTERFACE * | |
1987 | *********************************************************************/ | |
1988 | ||
1989 | /** | |
ec06e586 RW |
1990 | * cpufreq_register_notifier - Register a notifier with cpufreq. |
1991 | * @nb: notifier function to register. | |
1992 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 1993 | * |
ec06e586 RW |
1994 | * Add a notifier to one of two lists: either a list of notifiers that run on |
1995 | * clock rate changes (once before and once after every transition), or a list | |
1996 | * of notifiers that ron on cpufreq policy changes. | |
1da177e4 | 1997 | * |
ec06e586 RW |
1998 | * This function may sleep and it has the same return values as |
1999 | * blocking_notifier_chain_register(). | |
1da177e4 LT |
2000 | */ |
2001 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
2002 | { | |
2003 | int ret; | |
2004 | ||
d5aaffa9 DB |
2005 | if (cpufreq_disabled()) |
2006 | return -EINVAL; | |
2007 | ||
1da177e4 LT |
2008 | switch (list) { |
2009 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
2010 | mutex_lock(&cpufreq_fast_switch_lock); |
2011 | ||
2012 | if (cpufreq_fast_switch_count > 0) { | |
2013 | mutex_unlock(&cpufreq_fast_switch_lock); | |
2014 | return -EBUSY; | |
2015 | } | |
b4dfdbb3 | 2016 | ret = srcu_notifier_chain_register( |
e041c683 | 2017 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2018 | if (!ret) |
2019 | cpufreq_fast_switch_count--; | |
2020 | ||
2021 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2022 | break; |
2023 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2024 | ret = blocking_notifier_chain_register( |
2025 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2026 | break; |
2027 | default: | |
2028 | ret = -EINVAL; | |
2029 | } | |
1da177e4 LT |
2030 | |
2031 | return ret; | |
2032 | } | |
2033 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
2034 | ||
1da177e4 | 2035 | /** |
ec06e586 RW |
2036 | * cpufreq_unregister_notifier - Unregister a notifier from cpufreq. |
2037 | * @nb: notifier block to be unregistered. | |
2038 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER. | |
1da177e4 | 2039 | * |
ec06e586 | 2040 | * Remove a notifier from one of the cpufreq notifier lists. |
1da177e4 | 2041 | * |
ec06e586 RW |
2042 | * This function may sleep and it has the same return values as |
2043 | * blocking_notifier_chain_unregister(). | |
1da177e4 LT |
2044 | */ |
2045 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
2046 | { | |
2047 | int ret; | |
2048 | ||
d5aaffa9 DB |
2049 | if (cpufreq_disabled()) |
2050 | return -EINVAL; | |
2051 | ||
1da177e4 LT |
2052 | switch (list) { |
2053 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
2054 | mutex_lock(&cpufreq_fast_switch_lock); |
2055 | ||
b4dfdbb3 | 2056 | ret = srcu_notifier_chain_unregister( |
e041c683 | 2057 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2058 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
2059 | cpufreq_fast_switch_count++; | |
2060 | ||
2061 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2062 | break; |
2063 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2064 | ret = blocking_notifier_chain_unregister( |
2065 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2066 | break; |
2067 | default: | |
2068 | ret = -EINVAL; | |
2069 | } | |
1da177e4 LT |
2070 | |
2071 | return ret; | |
2072 | } | |
2073 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
2074 | ||
2075 | ||
2076 | /********************************************************************* | |
2077 | * GOVERNORS * | |
2078 | *********************************************************************/ | |
2079 | ||
b7898fda RW |
2080 | /** |
2081 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
2082 | * @policy: cpufreq policy to switch the frequency for. | |
2083 | * @target_freq: New frequency to set (may be approximate). | |
2084 | * | |
2085 | * Carry out a fast frequency switch without sleeping. | |
2086 | * | |
2087 | * The driver's ->fast_switch() callback invoked by this function must be | |
2088 | * suitable for being called from within RCU-sched read-side critical sections | |
2089 | * and it is expected to select the minimum available frequency greater than or | |
2090 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2091 | * | |
2092 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2093 | * | |
2094 | * Governors calling this function must guarantee that it will never be invoked | |
2095 | * twice in parallel for the same policy and that it will never be called in | |
2096 | * parallel with either ->target() or ->target_index() for the same policy. | |
2097 | * | |
209887e6 VK |
2098 | * Returns the actual frequency set for the CPU. |
2099 | * | |
2100 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2101 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2102 | */ |
2103 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2104 | unsigned int target_freq) | |
2105 | { | |
1a0419b0 | 2106 | unsigned int freq; |
08d8c65e | 2107 | int cpu; |
1a0419b0 | 2108 | |
b9af6948 | 2109 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
1a0419b0 IV |
2110 | freq = cpufreq_driver->fast_switch(policy, target_freq); |
2111 | ||
96f60cdd VK |
2112 | if (!freq) |
2113 | return 0; | |
2114 | ||
08d8c65e | 2115 | policy->cur = freq; |
1a0419b0 IV |
2116 | arch_set_freq_scale(policy->related_cpus, freq, |
2117 | policy->cpuinfo.max_freq); | |
96f60cdd | 2118 | cpufreq_stats_record_transition(policy, freq); |
b7898fda | 2119 | |
08d8c65e VK |
2120 | if (trace_cpu_frequency_enabled()) { |
2121 | for_each_cpu(cpu, policy->cpus) | |
2122 | trace_cpu_frequency(freq, cpu); | |
2123 | } | |
2124 | ||
1a0419b0 | 2125 | return freq; |
b7898fda RW |
2126 | } |
2127 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2128 | ||
ee2cc427 RW |
2129 | /** |
2130 | * cpufreq_driver_adjust_perf - Adjust CPU performance level in one go. | |
2131 | * @cpu: Target CPU. | |
2132 | * @min_perf: Minimum (required) performance level (units of @capacity). | |
4e6df217 | 2133 | * @target_perf: Target (desired) performance level (units of @capacity). |
ee2cc427 RW |
2134 | * @capacity: Capacity of the target CPU. |
2135 | * | |
2136 | * Carry out a fast performance level switch of @cpu without sleeping. | |
2137 | * | |
2138 | * The driver's ->adjust_perf() callback invoked by this function must be | |
2139 | * suitable for being called from within RCU-sched read-side critical sections | |
2140 | * and it is expected to select a suitable performance level equal to or above | |
2141 | * @min_perf and preferably equal to or below @target_perf. | |
2142 | * | |
2143 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2144 | * | |
2145 | * Governors calling this function must guarantee that it will never be invoked | |
2146 | * twice in parallel for the same CPU and that it will never be called in | |
2147 | * parallel with either ->target() or ->target_index() or ->fast_switch() for | |
2148 | * the same CPU. | |
2149 | */ | |
2150 | void cpufreq_driver_adjust_perf(unsigned int cpu, | |
2151 | unsigned long min_perf, | |
2152 | unsigned long target_perf, | |
2153 | unsigned long capacity) | |
2154 | { | |
2155 | cpufreq_driver->adjust_perf(cpu, min_perf, target_perf, capacity); | |
2156 | } | |
2157 | ||
2158 | /** | |
2159 | * cpufreq_driver_has_adjust_perf - Check "direct fast switch" callback. | |
2160 | * | |
2161 | * Return 'true' if the ->adjust_perf callback is present for the | |
2162 | * current driver or 'false' otherwise. | |
2163 | */ | |
2164 | bool cpufreq_driver_has_adjust_perf(void) | |
2165 | { | |
2166 | return !!cpufreq_driver->adjust_perf; | |
2167 | } | |
2168 | ||
1c03a2d0 VK |
2169 | /* Must set freqs->new to intermediate frequency */ |
2170 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2171 | struct cpufreq_freqs *freqs, int index) | |
2172 | { | |
2173 | int ret; | |
2174 | ||
2175 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2176 | ||
2177 | /* We don't need to switch to intermediate freq */ | |
2178 | if (!freqs->new) | |
2179 | return 0; | |
2180 | ||
2181 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2182 | __func__, policy->cpu, freqs->old, freqs->new); | |
2183 | ||
2184 | cpufreq_freq_transition_begin(policy, freqs); | |
2185 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2186 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2187 | ||
2188 | if (ret) | |
2189 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2190 | __func__, ret); | |
2191 | ||
2192 | return ret; | |
2193 | } | |
2194 | ||
23727845 | 2195 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2196 | { |
1c03a2d0 | 2197 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
56a7ff75 | 2198 | unsigned int restore_freq, intermediate_freq = 0; |
23727845 | 2199 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2200 | int retval = -EINVAL; |
2201 | bool notify; | |
2202 | ||
23727845 VK |
2203 | if (newfreq == policy->cur) |
2204 | return 0; | |
2205 | ||
56a7ff75 RW |
2206 | /* Save last value to restore later on errors */ |
2207 | restore_freq = policy->cur; | |
2208 | ||
8d65775d | 2209 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2210 | if (notify) { |
1c03a2d0 VK |
2211 | /* Handle switching to intermediate frequency */ |
2212 | if (cpufreq_driver->get_intermediate) { | |
2213 | retval = __target_intermediate(policy, &freqs, index); | |
2214 | if (retval) | |
2215 | return retval; | |
2216 | ||
2217 | intermediate_freq = freqs.new; | |
2218 | /* Set old freq to intermediate */ | |
2219 | if (intermediate_freq) | |
2220 | freqs.old = freqs.new; | |
2221 | } | |
8d65775d | 2222 | |
23727845 | 2223 | freqs.new = newfreq; |
8d65775d VK |
2224 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2225 | __func__, policy->cpu, freqs.old, freqs.new); | |
2226 | ||
2227 | cpufreq_freq_transition_begin(policy, &freqs); | |
2228 | } | |
2229 | ||
2230 | retval = cpufreq_driver->target_index(policy, index); | |
2231 | if (retval) | |
2232 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2233 | retval); | |
2234 | ||
1c03a2d0 | 2235 | if (notify) { |
8d65775d VK |
2236 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2237 | ||
1c03a2d0 VK |
2238 | /* |
2239 | * Failed after setting to intermediate freq? Driver should have | |
2240 | * reverted back to initial frequency and so should we. Check | |
2241 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2242 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2243 | */ |
2244 | if (unlikely(retval && intermediate_freq)) { | |
2245 | freqs.old = intermediate_freq; | |
56a7ff75 | 2246 | freqs.new = restore_freq; |
1c03a2d0 VK |
2247 | cpufreq_freq_transition_begin(policy, &freqs); |
2248 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2249 | } | |
2250 | } | |
2251 | ||
8d65775d VK |
2252 | return retval; |
2253 | } | |
2254 | ||
1da177e4 LT |
2255 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2256 | unsigned int target_freq, | |
2257 | unsigned int relation) | |
2258 | { | |
7249924e | 2259 | unsigned int old_target_freq = target_freq; |
c32b6b8e | 2260 | |
a7b422cd KRW |
2261 | if (cpufreq_disabled()) |
2262 | return -ENODEV; | |
2263 | ||
f9ccdec2 | 2264 | target_freq = __resolve_freq(policy, target_freq, relation); |
7249924e VK |
2265 | |
2266 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2267 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2268 | |
9c0ebcf7 VK |
2269 | /* |
2270 | * This might look like a redundant call as we are checking it again | |
2271 | * after finding index. But it is left intentionally for cases where | |
2272 | * exactly same freq is called again and so we can save on few function | |
2273 | * calls. | |
2274 | */ | |
1c534352 RW |
2275 | if (target_freq == policy->cur && |
2276 | !(cpufreq_driver->flags & CPUFREQ_NEED_UPDATE_LIMITS)) | |
5a1c0228 VK |
2277 | return 0; |
2278 | ||
1f39fa0d VD |
2279 | if (cpufreq_driver->target) { |
2280 | /* | |
2281 | * If the driver hasn't setup a single inefficient frequency, | |
2282 | * it's unlikely it knows how to decode CPUFREQ_RELATION_E. | |
2283 | */ | |
2284 | if (!policy->efficiencies_available) | |
2285 | relation &= ~CPUFREQ_RELATION_E; | |
2286 | ||
6019d23a | 2287 | return cpufreq_driver->target(policy, target_freq, relation); |
1f39fa0d | 2288 | } |
9c0ebcf7 | 2289 | |
6019d23a RW |
2290 | if (!cpufreq_driver->target_index) |
2291 | return -EINVAL; | |
9c0ebcf7 | 2292 | |
f9ccdec2 | 2293 | return __target_index(policy, policy->cached_resolved_idx); |
1da177e4 LT |
2294 | } |
2295 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2296 | ||
1da177e4 LT |
2297 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2298 | unsigned int target_freq, | |
2299 | unsigned int relation) | |
2300 | { | |
62c23a89 | 2301 | int ret; |
1da177e4 | 2302 | |
ad7722da | 2303 | down_write(&policy->rwsem); |
1da177e4 LT |
2304 | |
2305 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2306 | ||
ad7722da | 2307 | up_write(&policy->rwsem); |
1da177e4 | 2308 | |
1da177e4 LT |
2309 | return ret; |
2310 | } | |
2311 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2312 | ||
de1df26b RW |
2313 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2314 | { | |
2315 | return NULL; | |
2316 | } | |
2317 | ||
a92604b4 | 2318 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2319 | { |
cc993cab | 2320 | int ret; |
6afde10c | 2321 | |
2f0aea93 VK |
2322 | /* Don't start any governor operations if we are entering suspend */ |
2323 | if (cpufreq_suspended) | |
2324 | return 0; | |
cb57720b EZ |
2325 | /* |
2326 | * Governor might not be initiated here if ACPI _PPC changed | |
2327 | * notification happened, so check it. | |
2328 | */ | |
2329 | if (!policy->governor) | |
2330 | return -EINVAL; | |
2f0aea93 | 2331 | |
ed4676e2 | 2332 | /* Platform doesn't want dynamic frequency switching ? */ |
9a2a9ebc | 2333 | if (policy->governor->flags & CPUFREQ_GOV_DYNAMIC_SWITCHING && |
fc4c709f | 2334 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2335 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2336 | ||
2337 | if (gov) { | |
fe829ed8 | 2338 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2339 | policy->governor->name, gov->name); |
6afde10c | 2340 | policy->governor = gov; |
de1df26b RW |
2341 | } else { |
2342 | return -EINVAL; | |
6afde10c | 2343 | } |
1c256245 | 2344 | } |
1da177e4 | 2345 | |
a92604b4 RW |
2346 | if (!try_module_get(policy->governor->owner)) |
2347 | return -EINVAL; | |
95731ebb | 2348 | |
a92604b4 | 2349 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2350 | |
e788892b RW |
2351 | if (policy->governor->init) { |
2352 | ret = policy->governor->init(policy); | |
2353 | if (ret) { | |
36be3418 | 2354 | module_put(policy->governor->owner); |
e788892b RW |
2355 | return ret; |
2356 | } | |
36be3418 | 2357 | } |
1da177e4 | 2358 | |
ea9364bb RW |
2359 | policy->strict_target = !!(policy->governor->flags & CPUFREQ_GOV_STRICT_TARGET); |
2360 | ||
a92604b4 RW |
2361 | return 0; |
2362 | } | |
2363 | ||
2364 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2365 | { | |
2366 | if (cpufreq_suspended || !policy->governor) | |
2367 | return; | |
2368 | ||
2369 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2370 | ||
e788892b RW |
2371 | if (policy->governor->exit) |
2372 | policy->governor->exit(policy); | |
a92604b4 | 2373 | |
a92604b4 | 2374 | module_put(policy->governor->owner); |
1da177e4 LT |
2375 | } |
2376 | ||
f6ebbcf0 | 2377 | int cpufreq_start_governor(struct cpufreq_policy *policy) |
0a300767 RW |
2378 | { |
2379 | int ret; | |
2380 | ||
a92604b4 RW |
2381 | if (cpufreq_suspended) |
2382 | return 0; | |
2383 | ||
2384 | if (!policy->governor) | |
2385 | return -EINVAL; | |
2386 | ||
2387 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2388 | ||
407d0fff | 2389 | if (cpufreq_driver->get) |
5980752e | 2390 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2391 | |
e788892b RW |
2392 | if (policy->governor->start) { |
2393 | ret = policy->governor->start(policy); | |
2394 | if (ret) | |
2395 | return ret; | |
2396 | } | |
2397 | ||
2398 | if (policy->governor->limits) | |
2399 | policy->governor->limits(policy); | |
d6ff44d6 | 2400 | |
d6ff44d6 | 2401 | return 0; |
0a300767 RW |
2402 | } |
2403 | ||
f6ebbcf0 | 2404 | void cpufreq_stop_governor(struct cpufreq_policy *policy) |
a92604b4 RW |
2405 | { |
2406 | if (cpufreq_suspended || !policy->governor) | |
2407 | return; | |
2408 | ||
2409 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2410 | ||
e788892b RW |
2411 | if (policy->governor->stop) |
2412 | policy->governor->stop(policy); | |
a92604b4 RW |
2413 | } |
2414 | ||
2415 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2416 | { | |
2417 | if (cpufreq_suspended || !policy->governor) | |
2418 | return; | |
2419 | ||
2420 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2421 | ||
e788892b RW |
2422 | if (policy->governor->limits) |
2423 | policy->governor->limits(policy); | |
0a300767 RW |
2424 | } |
2425 | ||
1da177e4 LT |
2426 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2427 | { | |
3bcb09a3 | 2428 | int err; |
1da177e4 LT |
2429 | |
2430 | if (!governor) | |
2431 | return -EINVAL; | |
2432 | ||
a7b422cd KRW |
2433 | if (cpufreq_disabled()) |
2434 | return -ENODEV; | |
2435 | ||
3fc54d37 | 2436 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2437 | |
3bcb09a3 | 2438 | err = -EBUSY; |
42f91fa1 | 2439 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2440 | err = 0; |
2441 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2442 | } |
1da177e4 | 2443 | |
32ee8c3e | 2444 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2445 | return err; |
1da177e4 LT |
2446 | } |
2447 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2448 | ||
1da177e4 LT |
2449 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2450 | { | |
4573237b VK |
2451 | struct cpufreq_policy *policy; |
2452 | unsigned long flags; | |
90e41bac | 2453 | |
1da177e4 LT |
2454 | if (!governor) |
2455 | return; | |
2456 | ||
a7b422cd KRW |
2457 | if (cpufreq_disabled()) |
2458 | return; | |
2459 | ||
4573237b VK |
2460 | /* clear last_governor for all inactive policies */ |
2461 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2462 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2463 | if (!strcmp(policy->last_governor, governor->name)) { |
2464 | policy->governor = NULL; | |
4573237b | 2465 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2466 | } |
90e41bac | 2467 | } |
4573237b | 2468 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2469 | |
3fc54d37 | 2470 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2471 | list_del(&governor->governor_list); |
3fc54d37 | 2472 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2473 | } |
2474 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2475 | ||
2476 | ||
1da177e4 LT |
2477 | /********************************************************************* |
2478 | * POLICY INTERFACE * | |
2479 | *********************************************************************/ | |
2480 | ||
2481 | /** | |
2482 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2483 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2484 | * is written | |
a9909c21 | 2485 | * @cpu: CPU to find the policy for |
1da177e4 LT |
2486 | * |
2487 | * Reads the current cpufreq policy. | |
2488 | */ | |
2489 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2490 | { | |
2491 | struct cpufreq_policy *cpu_policy; | |
2492 | if (!policy) | |
2493 | return -EINVAL; | |
2494 | ||
2495 | cpu_policy = cpufreq_cpu_get(cpu); | |
2496 | if (!cpu_policy) | |
2497 | return -EINVAL; | |
2498 | ||
d5b73cd8 | 2499 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2500 | |
2501 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2502 | return 0; |
2503 | } | |
2504 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2505 | ||
a0dbb819 RW |
2506 | /** |
2507 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2508 | * @policy: Policy object to modify. | |
1e4f63ae RW |
2509 | * @new_gov: Policy governor pointer. |
2510 | * @new_pol: Policy value (for drivers with built-in governors). | |
a0dbb819 | 2511 | * |
1e4f63ae RW |
2512 | * Invoke the cpufreq driver's ->verify() callback to sanity-check the frequency |
2513 | * limits to be set for the policy, update @policy with the verified limits | |
2514 | * values and either invoke the driver's ->setpolicy() callback (if present) or | |
2515 | * carry out a governor update for @policy. That is, run the current governor's | |
2516 | * ->limits() callback (if @new_gov points to the same object as the one in | |
2517 | * @policy) or replace the governor for @policy with @new_gov. | |
a0dbb819 RW |
2518 | * |
2519 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2520 | */ |
1e4f63ae RW |
2521 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
2522 | struct cpufreq_governor *new_gov, | |
2523 | unsigned int new_pol) | |
1da177e4 | 2524 | { |
1e4f63ae | 2525 | struct cpufreq_policy_data new_data; |
d9a789c7 RW |
2526 | struct cpufreq_governor *old_gov; |
2527 | int ret; | |
1da177e4 | 2528 | |
1e4f63ae RW |
2529 | memcpy(&new_data.cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
2530 | new_data.freq_table = policy->freq_table; | |
2531 | new_data.cpu = policy->cpu; | |
fba9573b | 2532 | /* |
67d874c3 VK |
2533 | * PM QoS framework collects all the requests from users and provide us |
2534 | * the final aggregated value here. | |
2535 | */ | |
1e4f63ae RW |
2536 | new_data.min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); |
2537 | new_data.max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); | |
2538 | ||
2539 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", | |
2540 | new_data.cpu, new_data.min, new_data.max); | |
9c9a43ed | 2541 | |
737ffb27 VK |
2542 | /* |
2543 | * Verify that the CPU speed can be set within these limits and make sure | |
2544 | * that min <= max. | |
2545 | */ | |
1e4f63ae | 2546 | ret = cpufreq_driver->verify(&new_data); |
1da177e4 | 2547 | if (ret) |
d9a789c7 | 2548 | return ret; |
1da177e4 | 2549 | |
15171769 VD |
2550 | /* |
2551 | * Resolve policy min/max to available frequencies. It ensures | |
2552 | * no frequency resolution will neither overshoot the requested maximum | |
2553 | * nor undershoot the requested minimum. | |
2554 | */ | |
1e4f63ae RW |
2555 | policy->min = new_data.min; |
2556 | policy->max = new_data.max; | |
15171769 VD |
2557 | policy->min = __resolve_freq(policy, policy->min, CPUFREQ_RELATION_L); |
2558 | policy->max = __resolve_freq(policy, policy->max, CPUFREQ_RELATION_H); | |
601b2185 | 2559 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2560 | |
e3c06236 SM |
2561 | policy->cached_target_freq = UINT_MAX; |
2562 | ||
2d06d8c4 | 2563 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2564 | policy->min, policy->max); |
1da177e4 | 2565 | |
1c3d85dd | 2566 | if (cpufreq_driver->setpolicy) { |
1e4f63ae | 2567 | policy->policy = new_pol; |
2d06d8c4 | 2568 | pr_debug("setting range\n"); |
167a38dc | 2569 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2570 | } |
1da177e4 | 2571 | |
1e4f63ae | 2572 | if (new_gov == policy->governor) { |
2bb4059e | 2573 | pr_debug("governor limits update\n"); |
a92604b4 | 2574 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2575 | return 0; |
0a300767 | 2576 | } |
7bd353a9 | 2577 | |
d9a789c7 RW |
2578 | pr_debug("governor switch\n"); |
2579 | ||
2580 | /* save old, working values */ | |
2581 | old_gov = policy->governor; | |
2582 | /* end old governor */ | |
2583 | if (old_gov) { | |
45482c70 | 2584 | cpufreq_stop_governor(policy); |
36be3418 | 2585 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2586 | } |
2587 | ||
d9a789c7 | 2588 | /* start new governor */ |
1e4f63ae | 2589 | policy->governor = new_gov; |
a92604b4 | 2590 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2591 | if (!ret) { |
0a300767 RW |
2592 | ret = cpufreq_start_governor(policy); |
2593 | if (!ret) { | |
2bb4059e | 2594 | pr_debug("governor change\n"); |
531b5c9f | 2595 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2596 | return 0; |
2597 | } | |
b7898fda | 2598 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2599 | } |
2600 | ||
2601 | /* new governor failed, so re-start old one */ | |
2602 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2603 | if (old_gov) { | |
2604 | policy->governor = old_gov; | |
a92604b4 | 2605 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2606 | policy->governor = NULL; |
2607 | else | |
0a300767 | 2608 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2609 | } |
2610 | ||
4bc384ae | 2611 | return ret; |
1da177e4 LT |
2612 | } |
2613 | ||
1da177e4 | 2614 | /** |
a0dbb819 RW |
2615 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2616 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2617 | * |
a0dbb819 | 2618 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2619 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2620 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2621 | * for the policy in question, among other things. | |
1da177e4 | 2622 | */ |
30248fef | 2623 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2624 | { |
540a3758 | 2625 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2626 | |
fefa8ff8 | 2627 | if (!policy) |
30248fef | 2628 | return; |
1da177e4 | 2629 | |
bb176f7d VK |
2630 | /* |
2631 | * BIOS might change freq behind our back | |
2632 | * -> ask driver for current freq and notify governors about a change | |
2633 | */ | |
5ddc6d4e | 2634 | if (cpufreq_driver->get && has_target() && |
5980752e | 2635 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2636 | goto unlock; |
30248fef | 2637 | |
70a59fde | 2638 | refresh_frequency_limits(policy); |
1da177e4 | 2639 | |
fefa8ff8 | 2640 | unlock: |
540a3758 | 2641 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2642 | } |
2643 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2644 | ||
5a25e3f7 RW |
2645 | /** |
2646 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2647 | * @cpu: CPU to update the policy limits for. | |
2648 | * | |
2649 | * Invoke the driver's ->update_limits callback if present or call | |
2650 | * cpufreq_update_policy() for @cpu. | |
2651 | */ | |
2652 | void cpufreq_update_limits(unsigned int cpu) | |
2653 | { | |
2654 | if (cpufreq_driver->update_limits) | |
2655 | cpufreq_driver->update_limits(cpu); | |
2656 | else | |
2657 | cpufreq_update_policy(cpu); | |
2658 | } | |
2659 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2660 | ||
6f19efc0 LM |
2661 | /********************************************************************* |
2662 | * BOOST * | |
2663 | *********************************************************************/ | |
cf6fada7 | 2664 | static int cpufreq_boost_set_sw(struct cpufreq_policy *policy, int state) |
6f19efc0 | 2665 | { |
cf6fada7 | 2666 | int ret; |
49f18560 | 2667 | |
cf6fada7 XW |
2668 | if (!policy->freq_table) |
2669 | return -ENXIO; | |
f8bfc116 | 2670 | |
cf6fada7 XW |
2671 | ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table); |
2672 | if (ret) { | |
2673 | pr_err("%s: Policy frequency update failed\n", __func__); | |
2674 | return ret; | |
6f19efc0 LM |
2675 | } |
2676 | ||
cf6fada7 XW |
2677 | ret = freq_qos_update_request(policy->max_freq_req, policy->max); |
2678 | if (ret < 0) | |
2679 | return ret; | |
2680 | ||
552abb88 | 2681 | return 0; |
6f19efc0 LM |
2682 | } |
2683 | ||
2684 | int cpufreq_boost_trigger_state(int state) | |
2685 | { | |
cf6fada7 | 2686 | struct cpufreq_policy *policy; |
6f19efc0 LM |
2687 | unsigned long flags; |
2688 | int ret = 0; | |
2689 | ||
2690 | if (cpufreq_driver->boost_enabled == state) | |
2691 | return 0; | |
2692 | ||
2693 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2694 | cpufreq_driver->boost_enabled = state; | |
2695 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2696 | ||
09681a07 | 2697 | cpus_read_lock(); |
cf6fada7 XW |
2698 | for_each_active_policy(policy) { |
2699 | ret = cpufreq_driver->set_boost(policy, state); | |
2700 | if (ret) | |
2701 | goto err_reset_state; | |
6f19efc0 | 2702 | } |
09681a07 | 2703 | cpus_read_unlock(); |
cf6fada7 XW |
2704 | |
2705 | return 0; | |
2706 | ||
2707 | err_reset_state: | |
09681a07 | 2708 | cpus_read_unlock(); |
cf6fada7 XW |
2709 | |
2710 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2711 | cpufreq_driver->boost_enabled = !state; | |
2712 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2713 | ||
2714 | pr_err("%s: Cannot %s BOOST\n", | |
2715 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2716 | |
2717 | return ret; | |
2718 | } | |
2719 | ||
41669da0 | 2720 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2721 | { |
89f98d7e | 2722 | return cpufreq_driver->set_boost; |
6f19efc0 | 2723 | } |
6f19efc0 | 2724 | |
44139ed4 VK |
2725 | static int create_boost_sysfs_file(void) |
2726 | { | |
2727 | int ret; | |
2728 | ||
c82bd444 | 2729 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2730 | if (ret) |
2731 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2732 | __func__); | |
2733 | ||
2734 | return ret; | |
2735 | } | |
2736 | ||
2737 | static void remove_boost_sysfs_file(void) | |
2738 | { | |
2739 | if (cpufreq_boost_supported()) | |
c82bd444 | 2740 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2741 | } |
2742 | ||
2743 | int cpufreq_enable_boost_support(void) | |
2744 | { | |
2745 | if (!cpufreq_driver) | |
2746 | return -EINVAL; | |
2747 | ||
2748 | if (cpufreq_boost_supported()) | |
2749 | return 0; | |
2750 | ||
7a6c79f2 | 2751 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2752 | |
2753 | /* This will get removed on driver unregister */ | |
2754 | return create_boost_sysfs_file(); | |
2755 | } | |
2756 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2757 | ||
6f19efc0 LM |
2758 | int cpufreq_boost_enabled(void) |
2759 | { | |
2760 | return cpufreq_driver->boost_enabled; | |
2761 | } | |
2762 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2763 | ||
1da177e4 LT |
2764 | /********************************************************************* |
2765 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2766 | *********************************************************************/ | |
27622b06 | 2767 | static enum cpuhp_state hp_online; |
1da177e4 | 2768 | |
c4a3fa26 CY |
2769 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2770 | { | |
2771 | cpufreq_online(cpu); | |
2772 | ||
2773 | return 0; | |
2774 | } | |
2775 | ||
2776 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2777 | { | |
2778 | cpufreq_offline(cpu); | |
2779 | ||
2780 | return 0; | |
2781 | } | |
2782 | ||
1da177e4 LT |
2783 | /** |
2784 | * cpufreq_register_driver - register a CPU Frequency driver | |
2785 | * @driver_data: A struct cpufreq_driver containing the values# | |
2786 | * submitted by the CPU Frequency driver. | |
2787 | * | |
bb176f7d | 2788 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2789 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2790 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2791 | * |
2792 | */ | |
221dee28 | 2793 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2794 | { |
2795 | unsigned long flags; | |
2796 | int ret; | |
2797 | ||
a7b422cd KRW |
2798 | if (cpufreq_disabled()) |
2799 | return -ENODEV; | |
2800 | ||
46770be0 VK |
2801 | /* |
2802 | * The cpufreq core depends heavily on the availability of device | |
2803 | * structure, make sure they are available before proceeding further. | |
2804 | */ | |
2805 | if (!get_cpu_device(0)) | |
2806 | return -EPROBE_DEFER; | |
2807 | ||
1da177e4 | 2808 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2809 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2810 | driver_data->target) || |
2811 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2812 | driver_data->target)) || |
a9a22b57 | 2813 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2814 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2815 | return -EINVAL; |
2816 | ||
2d06d8c4 | 2817 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2818 | |
fdd320da | 2819 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2820 | cpus_read_lock(); |
fdd320da | 2821 | |
0d1857a1 | 2822 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2823 | if (cpufreq_driver) { |
0d1857a1 | 2824 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2825 | ret = -EEXIST; |
2826 | goto out; | |
1da177e4 | 2827 | } |
1c3d85dd | 2828 | cpufreq_driver = driver_data; |
0d1857a1 | 2829 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2830 | |
874f6353 IV |
2831 | /* |
2832 | * Mark support for the scheduler's frequency invariance engine for | |
2833 | * drivers that implement target(), target_index() or fast_switch(). | |
2834 | */ | |
2835 | if (!cpufreq_driver->setpolicy) { | |
2836 | static_branch_enable_cpuslocked(&cpufreq_freq_invariance); | |
2837 | pr_debug("supports frequency invariance"); | |
2838 | } | |
2839 | ||
bc68b7df VK |
2840 | if (driver_data->setpolicy) |
2841 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2842 | ||
7a6c79f2 RW |
2843 | if (cpufreq_boost_supported()) { |
2844 | ret = create_boost_sysfs_file(); | |
2845 | if (ret) | |
2846 | goto err_null_driver; | |
2847 | } | |
6f19efc0 | 2848 | |
8a25a2fd | 2849 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2850 | if (ret) |
6f19efc0 | 2851 | goto err_boost_unreg; |
1da177e4 | 2852 | |
5ae4a4b4 | 2853 | if (unlikely(list_empty(&cpufreq_policy_list))) { |
1da177e4 | 2854 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2855 | ret = -ENODEV; |
ce1bcfe9 VK |
2856 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2857 | driver_data->name); | |
2858 | goto err_if_unreg; | |
1da177e4 LT |
2859 | } |
2860 | ||
a92551e4 SAS |
2861 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2862 | "cpufreq:online", | |
2863 | cpuhp_cpufreq_online, | |
2864 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2865 | if (ret < 0) |
2866 | goto err_if_unreg; | |
2867 | hp_online = ret; | |
5372e054 | 2868 | ret = 0; |
27622b06 | 2869 | |
2d06d8c4 | 2870 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2871 | goto out; |
fdd320da | 2872 | |
8a25a2fd KS |
2873 | err_if_unreg: |
2874 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2875 | err_boost_unreg: |
44139ed4 | 2876 | remove_boost_sysfs_file(); |
8f5bc2ab | 2877 | err_null_driver: |
0d1857a1 | 2878 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2879 | cpufreq_driver = NULL; |
0d1857a1 | 2880 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2881 | out: |
a92551e4 | 2882 | cpus_read_unlock(); |
3834abb4 | 2883 | return ret; |
1da177e4 LT |
2884 | } |
2885 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2886 | ||
a9909c21 | 2887 | /* |
1da177e4 LT |
2888 | * cpufreq_unregister_driver - unregister the current CPUFreq driver |
2889 | * | |
bb176f7d | 2890 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2891 | * the right to do so, i.e. if you have succeeded in initialising before! |
2892 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2893 | * currently not initialised. | |
2894 | */ | |
221dee28 | 2895 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2896 | { |
2897 | unsigned long flags; | |
2898 | ||
1c3d85dd | 2899 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2900 | return -EINVAL; |
1da177e4 | 2901 | |
2d06d8c4 | 2902 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2903 | |
454d3a25 | 2904 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2905 | cpus_read_lock(); |
8a25a2fd | 2906 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2907 | remove_boost_sysfs_file(); |
874f6353 | 2908 | static_branch_disable_cpuslocked(&cpufreq_freq_invariance); |
a92551e4 | 2909 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2910 | |
0d1857a1 | 2911 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2912 | |
1c3d85dd | 2913 | cpufreq_driver = NULL; |
6eed9404 | 2914 | |
0d1857a1 | 2915 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2916 | cpus_read_unlock(); |
1da177e4 LT |
2917 | |
2918 | return 0; | |
2919 | } | |
2920 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2921 | |
2922 | static int __init cpufreq_core_init(void) | |
2923 | { | |
8412b456 QP |
2924 | struct cpufreq_governor *gov = cpufreq_default_governor(); |
2925 | ||
a7b422cd KRW |
2926 | if (cpufreq_disabled()) |
2927 | return -ENODEV; | |
2928 | ||
8eec1020 | 2929 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2930 | BUG_ON(!cpufreq_global_kobject); |
2931 | ||
8412b456 QP |
2932 | if (!strlen(default_governor)) |
2933 | strncpy(default_governor, gov->name, CPUFREQ_NAME_LEN); | |
2934 | ||
5a01f2e8 VP |
2935 | return 0; |
2936 | } | |
d82f2692 | 2937 | module_param(off, int, 0444); |
8412b456 | 2938 | module_param_string(default_governor, default_governor, CPUFREQ_NAME_LEN, 0444); |
5a01f2e8 | 2939 | core_initcall(cpufreq_core_init); |