Commit | Line | Data |
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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/drivers/cpufreq/cpufreq.c | |
4 | * | |
5 | * Copyright (C) 2001 Russell King | |
6 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 7 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 8 | * |
c32b6b8e | 9 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 10 | * Added handling for CPU hotplug |
8ff69732 DJ |
11 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
12 | * Fix handling for CPU hotplug -- affected CPUs | |
1da177e4 LT |
13 | */ |
14 | ||
db701151 VK |
15 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
16 | ||
5ff0a268 | 17 | #include <linux/cpu.h> |
1da177e4 | 18 | #include <linux/cpufreq.h> |
5c238a8b | 19 | #include <linux/cpu_cooling.h> |
1da177e4 | 20 | #include <linux/delay.h> |
1da177e4 | 21 | #include <linux/device.h> |
5ff0a268 VK |
22 | #include <linux/init.h> |
23 | #include <linux/kernel_stat.h> | |
24 | #include <linux/module.h> | |
3fc54d37 | 25 | #include <linux/mutex.h> |
67d874c3 | 26 | #include <linux/pm_qos.h> |
5ff0a268 | 27 | #include <linux/slab.h> |
2f0aea93 | 28 | #include <linux/suspend.h> |
90de2a4a | 29 | #include <linux/syscore_ops.h> |
5ff0a268 | 30 | #include <linux/tick.h> |
6f4f2723 TR |
31 | #include <trace/events/power.h> |
32 | ||
b4f0676f | 33 | static LIST_HEAD(cpufreq_policy_list); |
f963735a | 34 | |
f963735a | 35 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
36 | #define for_each_suitable_policy(__policy, __active) \ |
37 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
38 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
39 | |
40 | #define for_each_active_policy(__policy) \ | |
41 | for_each_suitable_policy(__policy, true) | |
42 | #define for_each_inactive_policy(__policy) \ | |
43 | for_each_suitable_policy(__policy, false) | |
44 | ||
45 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
46 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
47 | ||
f7b27061 VK |
48 | /* Iterate over governors */ |
49 | static LIST_HEAD(cpufreq_governor_list); | |
50 | #define for_each_governor(__governor) \ | |
51 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
52 | ||
8412b456 QP |
53 | static char default_governor[CPUFREQ_NAME_LEN]; |
54 | ||
a9909c21 | 55 | /* |
cd878479 | 56 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
57 | * level driver of CPUFreq support, and its spinlock. This lock |
58 | * also protects the cpufreq_cpu_data array. | |
59 | */ | |
1c3d85dd | 60 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 61 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 62 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 63 | |
874f6353 IV |
64 | static DEFINE_STATIC_KEY_FALSE(cpufreq_freq_invariance); |
65 | bool cpufreq_supports_freq_invariance(void) | |
66 | { | |
67 | return static_branch_likely(&cpufreq_freq_invariance); | |
68 | } | |
69 | ||
2f0aea93 VK |
70 | /* Flag to suspend/resume CPUFreq governors */ |
71 | static bool cpufreq_suspended; | |
1da177e4 | 72 | |
9c0ebcf7 VK |
73 | static inline bool has_target(void) |
74 | { | |
75 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
76 | } | |
77 | ||
1da177e4 | 78 | /* internal prototypes */ |
d92d50a4 | 79 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
80 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
81 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
a92604b4 | 82 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); |
1e4f63ae RW |
83 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
84 | struct cpufreq_governor *new_gov, | |
85 | unsigned int new_pol); | |
45482c70 | 86 | |
a9909c21 | 87 | /* |
32ee8c3e DJ |
88 | * Two notifier lists: the "policy" list is involved in the |
89 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
90 | * "transition" list for kernel code that needs to handle |
91 | * changes to devices when the CPU clock speed changes. | |
92 | * The mutex locks both lists. | |
93 | */ | |
e041c683 | 94 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 95 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 96 | |
a7b422cd | 97 | static int off __read_mostly; |
da584455 | 98 | static int cpufreq_disabled(void) |
a7b422cd KRW |
99 | { |
100 | return off; | |
101 | } | |
102 | void disable_cpufreq(void) | |
103 | { | |
104 | off = 1; | |
105 | } | |
29464f28 | 106 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 107 | |
4d5dcc42 VK |
108 | bool have_governor_per_policy(void) |
109 | { | |
0b981e70 | 110 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 111 | } |
3f869d6d | 112 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 113 | |
183edb20 YL |
114 | static struct kobject *cpufreq_global_kobject; |
115 | ||
944e9a03 VK |
116 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
117 | { | |
118 | if (have_governor_per_policy()) | |
119 | return &policy->kobj; | |
120 | else | |
121 | return cpufreq_global_kobject; | |
122 | } | |
123 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
124 | ||
72a4ce34 VK |
125 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
126 | { | |
5720821b | 127 | struct kernel_cpustat kcpustat; |
72a4ce34 | 128 | u64 cur_wall_time; |
5720821b | 129 | u64 idle_time; |
72a4ce34 VK |
130 | u64 busy_time; |
131 | ||
7fb1327e | 132 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 | 133 | |
5720821b FW |
134 | kcpustat_cpu_fetch(&kcpustat, cpu); |
135 | ||
136 | busy_time = kcpustat.cpustat[CPUTIME_USER]; | |
137 | busy_time += kcpustat.cpustat[CPUTIME_SYSTEM]; | |
138 | busy_time += kcpustat.cpustat[CPUTIME_IRQ]; | |
139 | busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ]; | |
140 | busy_time += kcpustat.cpustat[CPUTIME_STEAL]; | |
141 | busy_time += kcpustat.cpustat[CPUTIME_NICE]; | |
72a4ce34 VK |
142 | |
143 | idle_time = cur_wall_time - busy_time; | |
144 | if (wall) | |
7fb1327e | 145 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 146 | |
7fb1327e | 147 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
148 | } |
149 | ||
150 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
151 | { | |
152 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
153 | ||
154 | if (idle_time == -1ULL) | |
155 | return get_cpu_idle_time_jiffy(cpu, wall); | |
156 | else if (!io_busy) | |
157 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
158 | ||
159 | return idle_time; | |
160 | } | |
161 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
162 | ||
ecddc3a0 VS |
163 | __weak void arch_set_freq_scale(const struct cpumask *cpus, |
164 | unsigned long cur_freq, | |
165 | unsigned long max_freq) | |
e7d5459d DE |
166 | { |
167 | } | |
168 | EXPORT_SYMBOL_GPL(arch_set_freq_scale); | |
169 | ||
70e9e778 VK |
170 | /* |
171 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
172 | * drivers of SMP systems. It will do following: | |
173 | * - validate & show freq table passed | |
174 | * - set policies transition latency | |
175 | * - policy->cpus with all possible CPUs | |
176 | */ | |
c4dcc8a1 | 177 | void cpufreq_generic_init(struct cpufreq_policy *policy, |
70e9e778 VK |
178 | struct cpufreq_frequency_table *table, |
179 | unsigned int transition_latency) | |
180 | { | |
92c99d15 | 181 | policy->freq_table = table; |
70e9e778 VK |
182 | policy->cpuinfo.transition_latency = transition_latency; |
183 | ||
184 | /* | |
58405af6 | 185 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
186 | * share the clock and voltage and clock. |
187 | */ | |
188 | cpumask_setall(policy->cpus); | |
70e9e778 VK |
189 | } |
190 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
191 | ||
1f0bd44e | 192 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
193 | { |
194 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
195 | ||
988bed09 VK |
196 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
197 | } | |
1f0bd44e | 198 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
199 | |
200 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
201 | { | |
202 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
203 | ||
652ed95d | 204 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
205 | pr_err("%s: No %s associated to cpu: %d\n", |
206 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
207 | return 0; |
208 | } | |
209 | ||
210 | return clk_get_rate(policy->clk) / 1000; | |
211 | } | |
212 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
213 | ||
50e9c852 | 214 | /** |
5d094fea RW |
215 | * cpufreq_cpu_get - Return policy for a CPU and mark it as busy. |
216 | * @cpu: CPU to find the policy for. | |
50e9c852 | 217 | * |
5d094fea RW |
218 | * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment |
219 | * the kobject reference counter of that policy. Return a valid policy on | |
220 | * success or NULL on failure. | |
50e9c852 | 221 | * |
5d094fea RW |
222 | * The policy returned by this function has to be released with the help of |
223 | * cpufreq_cpu_put() to balance its kobject reference counter properly. | |
50e9c852 | 224 | */ |
6eed9404 | 225 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 226 | { |
6eed9404 | 227 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
228 | unsigned long flags; |
229 | ||
1b947c90 | 230 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
231 | return NULL; |
232 | ||
1da177e4 | 233 | /* get the cpufreq driver */ |
1c3d85dd | 234 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 235 | |
6eed9404 VK |
236 | if (cpufreq_driver) { |
237 | /* get the CPU */ | |
988bed09 | 238 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
239 | if (policy) |
240 | kobject_get(&policy->kobj); | |
241 | } | |
1da177e4 | 242 | |
6eed9404 | 243 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 244 | |
3a3e9e06 | 245 | return policy; |
a9144436 | 246 | } |
1da177e4 LT |
247 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
248 | ||
50e9c852 | 249 | /** |
5d094fea RW |
250 | * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy. |
251 | * @policy: cpufreq policy returned by cpufreq_cpu_get(). | |
50e9c852 | 252 | */ |
3a3e9e06 | 253 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 254 | { |
6eed9404 | 255 | kobject_put(&policy->kobj); |
1da177e4 LT |
256 | } |
257 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
258 | ||
540a3758 RW |
259 | /** |
260 | * cpufreq_cpu_release - Unlock a policy and decrement its usage counter. | |
261 | * @policy: cpufreq policy returned by cpufreq_cpu_acquire(). | |
262 | */ | |
9083e498 | 263 | void cpufreq_cpu_release(struct cpufreq_policy *policy) |
540a3758 RW |
264 | { |
265 | if (WARN_ON(!policy)) | |
266 | return; | |
267 | ||
268 | lockdep_assert_held(&policy->rwsem); | |
269 | ||
270 | up_write(&policy->rwsem); | |
271 | ||
272 | cpufreq_cpu_put(policy); | |
273 | } | |
274 | ||
275 | /** | |
276 | * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it. | |
277 | * @cpu: CPU to find the policy for. | |
278 | * | |
279 | * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and | |
280 | * if the policy returned by it is not NULL, acquire its rwsem for writing. | |
281 | * Return the policy if it is active or release it and return NULL otherwise. | |
282 | * | |
283 | * The policy returned by this function has to be released with the help of | |
284 | * cpufreq_cpu_release() in order to release its rwsem and balance its usage | |
285 | * counter properly. | |
286 | */ | |
9083e498 | 287 | struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) |
540a3758 RW |
288 | { |
289 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
290 | ||
291 | if (!policy) | |
292 | return NULL; | |
293 | ||
294 | down_write(&policy->rwsem); | |
295 | ||
296 | if (policy_is_inactive(policy)) { | |
297 | cpufreq_cpu_release(policy); | |
298 | return NULL; | |
299 | } | |
300 | ||
301 | return policy; | |
302 | } | |
303 | ||
1da177e4 LT |
304 | /********************************************************************* |
305 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
306 | *********************************************************************/ | |
307 | ||
a9909c21 | 308 | /* |
1da177e4 LT |
309 | * adjust_jiffies - adjust the system "loops_per_jiffy" |
310 | * | |
311 | * This function alters the system "loops_per_jiffy" for the clock | |
312 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 313 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
314 | * per-CPU loops_per_jiffy value wherever possible. |
315 | */ | |
858119e1 | 316 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 317 | { |
39c132ee VK |
318 | #ifndef CONFIG_SMP |
319 | static unsigned long l_p_j_ref; | |
320 | static unsigned int l_p_j_ref_freq; | |
321 | ||
1da177e4 LT |
322 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
323 | return; | |
324 | ||
325 | if (!l_p_j_ref_freq) { | |
326 | l_p_j_ref = loops_per_jiffy; | |
327 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
328 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
329 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 330 | } |
0b443ead | 331 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
332 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
333 | ci->new); | |
e837f9b5 JP |
334 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
335 | loops_per_jiffy, ci->new); | |
1da177e4 | 336 | } |
1da177e4 | 337 | #endif |
39c132ee | 338 | } |
1da177e4 | 339 | |
20b5324d VK |
340 | /** |
341 | * cpufreq_notify_transition - Notify frequency transition and adjust_jiffies. | |
342 | * @policy: cpufreq policy to enable fast frequency switching for. | |
343 | * @freqs: contain details of the frequency update. | |
344 | * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
345 | * | |
346 | * This function calls the transition notifiers and the "adjust_jiffies" | |
347 | * function. It is called twice on all CPU frequency changes that have | |
348 | * external effects. | |
349 | */ | |
350 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
351 | struct cpufreq_freqs *freqs, | |
352 | unsigned int state) | |
1da177e4 | 353 | { |
df24014a VK |
354 | int cpu; |
355 | ||
1da177e4 LT |
356 | BUG_ON(irqs_disabled()); |
357 | ||
d5aaffa9 DB |
358 | if (cpufreq_disabled()) |
359 | return; | |
360 | ||
df24014a | 361 | freqs->policy = policy; |
1c3d85dd | 362 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 363 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 364 | state, freqs->new); |
1da177e4 | 365 | |
1da177e4 LT |
366 | switch (state) { |
367 | case CPUFREQ_PRECHANGE: | |
20b5324d VK |
368 | /* |
369 | * Detect if the driver reported a value as "old frequency" | |
e4472cb3 DJ |
370 | * which is not equal to what the cpufreq core thinks is |
371 | * "old frequency". | |
1da177e4 | 372 | */ |
98015228 VK |
373 | if (policy->cur && policy->cur != freqs->old) { |
374 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", | |
375 | freqs->old, policy->cur); | |
376 | freqs->old = policy->cur; | |
1da177e4 | 377 | } |
20b5324d | 378 | |
df24014a VK |
379 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
380 | CPUFREQ_PRECHANGE, freqs); | |
20b5324d | 381 | |
1da177e4 LT |
382 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
383 | break; | |
e4472cb3 | 384 | |
1da177e4 LT |
385 | case CPUFREQ_POSTCHANGE: |
386 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
20b5324d VK |
387 | pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, |
388 | cpumask_pr_args(policy->cpus)); | |
389 | ||
df24014a VK |
390 | for_each_cpu(cpu, policy->cpus) |
391 | trace_cpu_frequency(freqs->new, cpu); | |
392 | ||
393 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, | |
394 | CPUFREQ_POSTCHANGE, freqs); | |
20b5324d | 395 | |
1aefc75b | 396 | cpufreq_stats_record_transition(policy, freqs->new); |
20b5324d | 397 | policy->cur = freqs->new; |
1da177e4 | 398 | } |
1da177e4 | 399 | } |
bb176f7d | 400 | |
f7ba3b41 | 401 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 402 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
403 | struct cpufreq_freqs *freqs, int transition_failed) |
404 | { | |
405 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
406 | if (!transition_failed) | |
407 | return; | |
408 | ||
409 | swap(freqs->old, freqs->new); | |
410 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
411 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
412 | } | |
f7ba3b41 | 413 | |
12478cf0 SB |
414 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
415 | struct cpufreq_freqs *freqs) | |
416 | { | |
ca654dc3 SB |
417 | |
418 | /* | |
419 | * Catch double invocations of _begin() which lead to self-deadlock. | |
420 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
421 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
422 | * double invocations are very low. Moreover, there are scenarios | |
423 | * where these checks can emit false-positive warnings in these | |
424 | * drivers; so we avoid that by skipping them altogether. | |
425 | */ | |
426 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
427 | && current == policy->transition_task); | |
428 | ||
12478cf0 SB |
429 | wait: |
430 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
431 | ||
432 | spin_lock(&policy->transition_lock); | |
433 | ||
434 | if (unlikely(policy->transition_ongoing)) { | |
435 | spin_unlock(&policy->transition_lock); | |
436 | goto wait; | |
437 | } | |
438 | ||
439 | policy->transition_ongoing = true; | |
ca654dc3 | 440 | policy->transition_task = current; |
12478cf0 SB |
441 | |
442 | spin_unlock(&policy->transition_lock); | |
443 | ||
444 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
445 | } | |
446 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
447 | ||
448 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
449 | struct cpufreq_freqs *freqs, int transition_failed) | |
450 | { | |
0e7ea2f3 | 451 | if (WARN_ON(!policy->transition_ongoing)) |
12478cf0 SB |
452 | return; |
453 | ||
454 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
455 | ||
1a0419b0 IV |
456 | arch_set_freq_scale(policy->related_cpus, |
457 | policy->cur, | |
458 | policy->cpuinfo.max_freq); | |
459 | ||
12478cf0 | 460 | policy->transition_ongoing = false; |
ca654dc3 | 461 | policy->transition_task = NULL; |
12478cf0 SB |
462 | |
463 | wake_up(&policy->transition_wait); | |
464 | } | |
465 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
466 | ||
b7898fda RW |
467 | /* |
468 | * Fast frequency switching status count. Positive means "enabled", negative | |
469 | * means "disabled" and 0 means "not decided yet". | |
470 | */ | |
471 | static int cpufreq_fast_switch_count; | |
472 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
473 | ||
474 | static void cpufreq_list_transition_notifiers(void) | |
475 | { | |
476 | struct notifier_block *nb; | |
477 | ||
478 | pr_info("Registered transition notifiers:\n"); | |
479 | ||
480 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
481 | ||
482 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
d75f773c | 483 | pr_info("%pS\n", nb->notifier_call); |
b7898fda RW |
484 | |
485 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
486 | } | |
487 | ||
488 | /** | |
489 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
490 | * @policy: cpufreq policy to enable fast frequency switching for. | |
491 | * | |
492 | * Try to enable fast frequency switching for @policy. | |
493 | * | |
494 | * The attempt will fail if there is at least one transition notifier registered | |
495 | * at this point, as fast frequency switching is quite fundamentally at odds | |
496 | * with transition notifiers. Thus if successful, it will make registration of | |
497 | * transition notifiers fail going forward. | |
498 | */ | |
499 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
500 | { | |
501 | lockdep_assert_held(&policy->rwsem); | |
502 | ||
503 | if (!policy->fast_switch_possible) | |
504 | return; | |
505 | ||
506 | mutex_lock(&cpufreq_fast_switch_lock); | |
507 | if (cpufreq_fast_switch_count >= 0) { | |
508 | cpufreq_fast_switch_count++; | |
509 | policy->fast_switch_enabled = true; | |
510 | } else { | |
511 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
512 | policy->cpu); | |
513 | cpufreq_list_transition_notifiers(); | |
514 | } | |
515 | mutex_unlock(&cpufreq_fast_switch_lock); | |
516 | } | |
517 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
518 | ||
6c9d9c81 RW |
519 | /** |
520 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
521 | * @policy: cpufreq policy to disable fast frequency switching for. | |
522 | */ | |
523 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
524 | { |
525 | mutex_lock(&cpufreq_fast_switch_lock); | |
526 | if (policy->fast_switch_enabled) { | |
527 | policy->fast_switch_enabled = false; | |
528 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
529 | cpufreq_fast_switch_count--; | |
530 | } | |
531 | mutex_unlock(&cpufreq_fast_switch_lock); | |
532 | } | |
6c9d9c81 | 533 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 534 | |
e3c06236 SM |
535 | /** |
536 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
537 | * one. | |
a9909c21 | 538 | * @policy: associated policy to interrogate |
e3c06236 SM |
539 | * @target_freq: target frequency to resolve. |
540 | * | |
541 | * The target to driver frequency mapping is cached in the policy. | |
542 | * | |
543 | * Return: Lowest driver-supported frequency greater than or equal to the | |
544 | * given target_freq, subject to policy (min/max) and driver limitations. | |
545 | */ | |
546 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
547 | unsigned int target_freq) | |
548 | { | |
549 | target_freq = clamp_val(target_freq, policy->min, policy->max); | |
550 | policy->cached_target_freq = target_freq; | |
abe8bd02 VK |
551 | |
552 | if (cpufreq_driver->target_index) { | |
292072c3 | 553 | unsigned int idx; |
abe8bd02 VK |
554 | |
555 | idx = cpufreq_frequency_table_target(policy, target_freq, | |
556 | CPUFREQ_RELATION_L); | |
557 | policy->cached_resolved_idx = idx; | |
558 | return policy->freq_table[idx].frequency; | |
559 | } | |
560 | ||
e3c06236 SM |
561 | if (cpufreq_driver->resolve_freq) |
562 | return cpufreq_driver->resolve_freq(policy, target_freq); | |
abe8bd02 VK |
563 | |
564 | return target_freq; | |
e3c06236 | 565 | } |
ae2c1ca6 | 566 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 567 | |
aa7519af VK |
568 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
569 | { | |
570 | unsigned int latency; | |
571 | ||
572 | if (policy->transition_delay_us) | |
573 | return policy->transition_delay_us; | |
574 | ||
575 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
576 | if (latency) { |
577 | /* | |
578 | * For platforms that can change the frequency very fast (< 10 | |
579 | * us), the above formula gives a decent transition delay. But | |
580 | * for platforms where transition_latency is in milliseconds, it | |
581 | * ends up giving unrealistic values. | |
582 | * | |
583 | * Cap the default transition delay to 10 ms, which seems to be | |
584 | * a reasonable amount of time after which we should reevaluate | |
585 | * the frequency. | |
586 | */ | |
587 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
588 | } | |
aa7519af VK |
589 | |
590 | return LATENCY_MULTIPLIER; | |
591 | } | |
592 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
593 | ||
1da177e4 LT |
594 | /********************************************************************* |
595 | * SYSFS INTERFACE * | |
596 | *********************************************************************/ | |
8a5c74a1 | 597 | static ssize_t show_boost(struct kobject *kobj, |
625c85a6 | 598 | struct kobj_attribute *attr, char *buf) |
6f19efc0 LM |
599 | { |
600 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
601 | } | |
602 | ||
625c85a6 VK |
603 | static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, |
604 | const char *buf, size_t count) | |
6f19efc0 LM |
605 | { |
606 | int ret, enable; | |
607 | ||
608 | ret = sscanf(buf, "%d", &enable); | |
609 | if (ret != 1 || enable < 0 || enable > 1) | |
610 | return -EINVAL; | |
611 | ||
612 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
613 | pr_err("%s: Cannot %s BOOST!\n", |
614 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
615 | return -EINVAL; |
616 | } | |
617 | ||
e837f9b5 JP |
618 | pr_debug("%s: cpufreq BOOST %s\n", |
619 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
620 | |
621 | return count; | |
622 | } | |
623 | define_one_global_rw(boost); | |
1da177e4 | 624 | |
42f91fa1 | 625 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
626 | { |
627 | struct cpufreq_governor *t; | |
628 | ||
f7b27061 | 629 | for_each_governor(t) |
7c4f4539 | 630 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
631 | return t; |
632 | ||
633 | return NULL; | |
634 | } | |
635 | ||
8cc46ae5 VK |
636 | static struct cpufreq_governor *get_governor(const char *str_governor) |
637 | { | |
638 | struct cpufreq_governor *t; | |
639 | ||
640 | mutex_lock(&cpufreq_governor_mutex); | |
641 | t = find_governor(str_governor); | |
642 | if (!t) | |
643 | goto unlock; | |
644 | ||
645 | if (!try_module_get(t->owner)) | |
646 | t = NULL; | |
647 | ||
648 | unlock: | |
649 | mutex_unlock(&cpufreq_governor_mutex); | |
650 | ||
651 | return t; | |
652 | } | |
653 | ||
1e4f63ae | 654 | static unsigned int cpufreq_parse_policy(char *str_governor) |
ab05d97a | 655 | { |
1e4f63ae RW |
656 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) |
657 | return CPUFREQ_POLICY_PERFORMANCE; | |
658 | ||
659 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) | |
660 | return CPUFREQ_POLICY_POWERSAVE; | |
661 | ||
662 | return CPUFREQ_POLICY_UNKNOWN; | |
ab05d97a YH |
663 | } |
664 | ||
1da177e4 | 665 | /** |
5ddc6d4e | 666 | * cpufreq_parse_governor - parse a governor string only for has_target() |
1e4f63ae | 667 | * @str_governor: Governor name. |
1da177e4 | 668 | */ |
1e4f63ae | 669 | static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor) |
1da177e4 | 670 | { |
ab05d97a | 671 | struct cpufreq_governor *t; |
045149e6 | 672 | |
8cc46ae5 VK |
673 | t = get_governor(str_governor); |
674 | if (t) | |
675 | return t; | |
ea714970 | 676 | |
8cc46ae5 VK |
677 | if (request_module("cpufreq_%s", str_governor)) |
678 | return NULL; | |
045149e6 | 679 | |
8cc46ae5 | 680 | return get_governor(str_governor); |
1da177e4 | 681 | } |
1da177e4 | 682 | |
a9909c21 | 683 | /* |
e08f5f5b GS |
684 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
685 | * print out cpufreq information | |
1da177e4 LT |
686 | * |
687 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
688 | * "unsigned int". | |
689 | */ | |
690 | ||
32ee8c3e DJ |
691 | #define show_one(file_name, object) \ |
692 | static ssize_t show_##file_name \ | |
905d77cd | 693 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 694 | { \ |
29464f28 | 695 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
696 | } |
697 | ||
698 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
699 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 700 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
701 | show_one(scaling_min_freq, min); |
702 | show_one(scaling_max_freq, max); | |
c034b02e | 703 | |
f8475cef LB |
704 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
705 | { | |
706 | return 0; | |
707 | } | |
708 | ||
09347b29 | 709 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
710 | { |
711 | ssize_t ret; | |
f8475cef | 712 | unsigned int freq; |
c034b02e | 713 | |
f8475cef LB |
714 | freq = arch_freq_get_on_cpu(policy->cpu); |
715 | if (freq) | |
716 | ret = sprintf(buf, "%u\n", freq); | |
681fe684 | 717 | else if (cpufreq_driver->setpolicy && cpufreq_driver->get) |
c034b02e DB |
718 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
719 | else | |
720 | ret = sprintf(buf, "%u\n", policy->cur); | |
721 | return ret; | |
722 | } | |
1da177e4 | 723 | |
a9909c21 | 724 | /* |
1da177e4 LT |
725 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access |
726 | */ | |
727 | #define store_one(file_name, object) \ | |
728 | static ssize_t store_##file_name \ | |
905d77cd | 729 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 730 | { \ |
18c49926 VK |
731 | unsigned long val; \ |
732 | int ret; \ | |
1da177e4 | 733 | \ |
18c49926 | 734 | ret = sscanf(buf, "%lu", &val); \ |
1da177e4 LT |
735 | if (ret != 1) \ |
736 | return -EINVAL; \ | |
737 | \ | |
3000ce3c | 738 | ret = freq_qos_update_request(policy->object##_freq_req, val);\ |
18c49926 | 739 | return ret >= 0 ? count : ret; \ |
1da177e4 LT |
740 | } |
741 | ||
29464f28 DJ |
742 | store_one(scaling_min_freq, min); |
743 | store_one(scaling_max_freq, max); | |
1da177e4 | 744 | |
a9909c21 | 745 | /* |
1da177e4 LT |
746 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware |
747 | */ | |
905d77cd DJ |
748 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
749 | char *buf) | |
1da177e4 | 750 | { |
d92d50a4 | 751 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
752 | |
753 | if (cur_freq) | |
754 | return sprintf(buf, "%u\n", cur_freq); | |
755 | ||
756 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
757 | } |
758 | ||
a9909c21 | 759 | /* |
1da177e4 LT |
760 | * show_scaling_governor - show the current policy for the specified CPU |
761 | */ | |
905d77cd | 762 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 763 | { |
29464f28 | 764 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
765 | return sprintf(buf, "powersave\n"); |
766 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
767 | return sprintf(buf, "performance\n"); | |
768 | else if (policy->governor) | |
4b972f0b | 769 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 770 | policy->governor->name); |
1da177e4 LT |
771 | return -EINVAL; |
772 | } | |
773 | ||
a9909c21 | 774 | /* |
1da177e4 LT |
775 | * store_scaling_governor - store policy for the specified CPU |
776 | */ | |
905d77cd DJ |
777 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
778 | const char *buf, size_t count) | |
1da177e4 | 779 | { |
1e4f63ae | 780 | char str_governor[16]; |
5136fa56 | 781 | int ret; |
1da177e4 | 782 | |
29464f28 | 783 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
784 | if (ret != 1) |
785 | return -EINVAL; | |
786 | ||
ab05d97a | 787 | if (cpufreq_driver->setpolicy) { |
1e4f63ae RW |
788 | unsigned int new_pol; |
789 | ||
790 | new_pol = cpufreq_parse_policy(str_governor); | |
791 | if (!new_pol) | |
ab05d97a | 792 | return -EINVAL; |
1e4f63ae RW |
793 | |
794 | ret = cpufreq_set_policy(policy, NULL, new_pol); | |
ab05d97a | 795 | } else { |
1e4f63ae RW |
796 | struct cpufreq_governor *new_gov; |
797 | ||
798 | new_gov = cpufreq_parse_governor(str_governor); | |
799 | if (!new_gov) | |
ab05d97a | 800 | return -EINVAL; |
1da177e4 | 801 | |
1e4f63ae RW |
802 | ret = cpufreq_set_policy(policy, new_gov, |
803 | CPUFREQ_POLICY_UNKNOWN); | |
a8b149d3 | 804 | |
1e4f63ae RW |
805 | module_put(new_gov->owner); |
806 | } | |
a8b149d3 | 807 | |
88dc4384 | 808 | return ret ? ret : count; |
1da177e4 LT |
809 | } |
810 | ||
a9909c21 | 811 | /* |
1da177e4 LT |
812 | * show_scaling_driver - show the cpufreq driver currently loaded |
813 | */ | |
905d77cd | 814 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 815 | { |
1c3d85dd | 816 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
817 | } |
818 | ||
a9909c21 | 819 | /* |
1da177e4 LT |
820 | * show_scaling_available_governors - show the available CPUfreq governors |
821 | */ | |
905d77cd DJ |
822 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
823 | char *buf) | |
1da177e4 LT |
824 | { |
825 | ssize_t i = 0; | |
826 | struct cpufreq_governor *t; | |
827 | ||
9c0ebcf7 | 828 | if (!has_target()) { |
1da177e4 LT |
829 | i += sprintf(buf, "performance powersave"); |
830 | goto out; | |
831 | } | |
832 | ||
8cc46ae5 | 833 | mutex_lock(&cpufreq_governor_mutex); |
f7b27061 | 834 | for_each_governor(t) { |
29464f28 DJ |
835 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
836 | - (CPUFREQ_NAME_LEN + 2))) | |
8cc46ae5 | 837 | break; |
4b972f0b | 838 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 839 | } |
8cc46ae5 | 840 | mutex_unlock(&cpufreq_governor_mutex); |
7d5e350f | 841 | out: |
1da177e4 LT |
842 | i += sprintf(&buf[i], "\n"); |
843 | return i; | |
844 | } | |
e8628dd0 | 845 | |
f4fd3797 | 846 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
847 | { |
848 | ssize_t i = 0; | |
849 | unsigned int cpu; | |
850 | ||
835481d9 | 851 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
852 | if (i) |
853 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
854 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
855 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 856 | break; |
1da177e4 LT |
857 | } |
858 | i += sprintf(&buf[i], "\n"); | |
859 | return i; | |
860 | } | |
f4fd3797 | 861 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 862 | |
a9909c21 | 863 | /* |
e8628dd0 DW |
864 | * show_related_cpus - show the CPUs affected by each transition even if |
865 | * hw coordination is in use | |
866 | */ | |
867 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
868 | { | |
f4fd3797 | 869 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
870 | } |
871 | ||
a9909c21 | 872 | /* |
e8628dd0 DW |
873 | * show_affected_cpus - show the CPUs affected by each transition |
874 | */ | |
875 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
876 | { | |
f4fd3797 | 877 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
878 | } |
879 | ||
9e76988e | 880 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 881 | const char *buf, size_t count) |
9e76988e VP |
882 | { |
883 | unsigned int freq = 0; | |
884 | unsigned int ret; | |
885 | ||
879000f9 | 886 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
887 | return -EINVAL; |
888 | ||
889 | ret = sscanf(buf, "%u", &freq); | |
890 | if (ret != 1) | |
891 | return -EINVAL; | |
892 | ||
893 | policy->governor->store_setspeed(policy, freq); | |
894 | ||
895 | return count; | |
896 | } | |
897 | ||
898 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
899 | { | |
879000f9 | 900 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
901 | return sprintf(buf, "<unsupported>\n"); |
902 | ||
903 | return policy->governor->show_setspeed(policy, buf); | |
904 | } | |
1da177e4 | 905 | |
a9909c21 | 906 | /* |
8bf1ac72 | 907 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
908 | */ |
909 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
910 | { | |
911 | unsigned int limit; | |
912 | int ret; | |
b23aa311 YH |
913 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
914 | if (!ret) | |
915 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
916 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
917 | } | |
918 | ||
6dad2a29 BP |
919 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
920 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
921 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
922 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
923 | cpufreq_freq_attr_ro(scaling_available_governors); | |
924 | cpufreq_freq_attr_ro(scaling_driver); | |
925 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
926 | cpufreq_freq_attr_ro(bios_limit); | |
927 | cpufreq_freq_attr_ro(related_cpus); | |
928 | cpufreq_freq_attr_ro(affected_cpus); | |
929 | cpufreq_freq_attr_rw(scaling_min_freq); | |
930 | cpufreq_freq_attr_rw(scaling_max_freq); | |
931 | cpufreq_freq_attr_rw(scaling_governor); | |
932 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 933 | |
905d77cd | 934 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
935 | &cpuinfo_min_freq.attr, |
936 | &cpuinfo_max_freq.attr, | |
ed129784 | 937 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
938 | &scaling_min_freq.attr, |
939 | &scaling_max_freq.attr, | |
940 | &affected_cpus.attr, | |
e8628dd0 | 941 | &related_cpus.attr, |
1da177e4 LT |
942 | &scaling_governor.attr, |
943 | &scaling_driver.attr, | |
944 | &scaling_available_governors.attr, | |
9e76988e | 945 | &scaling_setspeed.attr, |
1da177e4 LT |
946 | NULL |
947 | }; | |
948 | ||
29464f28 DJ |
949 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
950 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 951 | |
29464f28 | 952 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 953 | { |
905d77cd DJ |
954 | struct cpufreq_policy *policy = to_policy(kobj); |
955 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 956 | ssize_t ret; |
6eed9404 | 957 | |
e6e8df07 KS |
958 | if (!fattr->show) |
959 | return -EIO; | |
960 | ||
ad7722da | 961 | down_read(&policy->rwsem); |
6541aef0 | 962 | ret = fattr->show(policy, buf); |
ad7722da | 963 | up_read(&policy->rwsem); |
1b750e3b | 964 | |
1da177e4 LT |
965 | return ret; |
966 | } | |
967 | ||
905d77cd DJ |
968 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
969 | const char *buf, size_t count) | |
1da177e4 | 970 | { |
905d77cd DJ |
971 | struct cpufreq_policy *policy = to_policy(kobj); |
972 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 973 | ssize_t ret = -EINVAL; |
6eed9404 | 974 | |
e6e8df07 KS |
975 | if (!fattr->store) |
976 | return -EIO; | |
977 | ||
9b3d9bb3 WL |
978 | /* |
979 | * cpus_read_trylock() is used here to work around a circular lock | |
980 | * dependency problem with respect to the cpufreq_register_driver(). | |
981 | */ | |
982 | if (!cpus_read_trylock()) | |
983 | return -EBUSY; | |
4f750c93 | 984 | |
6541aef0 RW |
985 | if (cpu_online(policy->cpu)) { |
986 | down_write(&policy->rwsem); | |
e08f5f5b | 987 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
988 | up_write(&policy->rwsem); |
989 | } | |
e08f5f5b | 990 | |
a92551e4 | 991 | cpus_read_unlock(); |
4f750c93 | 992 | |
1da177e4 LT |
993 | return ret; |
994 | } | |
995 | ||
905d77cd | 996 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 997 | { |
905d77cd | 998 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 999 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
1000 | complete(&policy->kobj_unregister); |
1001 | } | |
1002 | ||
52cf25d0 | 1003 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
1004 | .show = show, |
1005 | .store = store, | |
1006 | }; | |
1007 | ||
1008 | static struct kobj_type ktype_cpufreq = { | |
1009 | .sysfs_ops = &sysfs_ops, | |
1010 | .default_attrs = default_attrs, | |
1011 | .release = cpufreq_sysfs_release, | |
1012 | }; | |
1013 | ||
2f0ba790 | 1014 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) |
87549141 | 1015 | { |
2f0ba790 RW |
1016 | struct device *dev = get_cpu_device(cpu); |
1017 | ||
67d874c3 | 1018 | if (unlikely(!dev)) |
2f0ba790 RW |
1019 | return; |
1020 | ||
1021 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
1022 | return; | |
1023 | ||
26619804 | 1024 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
1025 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
1026 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
1027 | } |
1028 | ||
26619804 VK |
1029 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
1030 | struct device *dev) | |
87549141 | 1031 | { |
26619804 VK |
1032 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1033 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
1034 | } |
1035 | ||
d9612a49 | 1036 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
1037 | { |
1038 | struct freq_attr **drv_attr; | |
909a694e | 1039 | int ret = 0; |
909a694e | 1040 | |
909a694e | 1041 | /* set up files for this cpu device */ |
1c3d85dd | 1042 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1043 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1044 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1045 | if (ret) | |
6d4e81ed | 1046 | return ret; |
909a694e DJ |
1047 | drv_attr++; |
1048 | } | |
1c3d85dd | 1049 | if (cpufreq_driver->get) { |
909a694e DJ |
1050 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1051 | if (ret) | |
6d4e81ed | 1052 | return ret; |
909a694e | 1053 | } |
c034b02e DB |
1054 | |
1055 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1056 | if (ret) | |
6d4e81ed | 1057 | return ret; |
c034b02e | 1058 | |
1c3d85dd | 1059 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1060 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1061 | if (ret) | |
6d4e81ed | 1062 | return ret; |
e2f74f35 | 1063 | } |
909a694e | 1064 | |
26619804 | 1065 | return 0; |
e18f1682 SB |
1066 | } |
1067 | ||
7f0fa40f | 1068 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1069 | { |
1e4f63ae RW |
1070 | struct cpufreq_governor *gov = NULL; |
1071 | unsigned int pol = CPUFREQ_POLICY_UNKNOWN; | |
8cc46ae5 | 1072 | int ret; |
ab05d97a YH |
1073 | |
1074 | if (has_target()) { | |
1e4f63ae | 1075 | /* Update policy governor to the one used before hotplug. */ |
8cc46ae5 | 1076 | gov = get_governor(policy->last_governor); |
ab05d97a YH |
1077 | if (gov) { |
1078 | pr_debug("Restoring governor %s for cpu %d\n", | |
8412b456 | 1079 | gov->name, policy->cpu); |
1e4f63ae | 1080 | } else { |
8412b456 QP |
1081 | gov = get_governor(default_governor); |
1082 | } | |
1083 | ||
1084 | if (!gov) { | |
1085 | gov = cpufreq_default_governor(); | |
8412b456 | 1086 | __module_get(gov->owner); |
ab05d97a | 1087 | } |
8412b456 | 1088 | |
de1df26b | 1089 | } else { |
8412b456 | 1090 | |
ab05d97a YH |
1091 | /* Use the default policy if there is no last_policy. */ |
1092 | if (policy->last_policy) { | |
1e4f63ae | 1093 | pol = policy->last_policy; |
8412b456 QP |
1094 | } else { |
1095 | pol = cpufreq_parse_policy(default_governor); | |
f5739cb0 | 1096 | /* |
8412b456 | 1097 | * In case the default governor is neither "performance" |
f5739cb0 RW |
1098 | * nor "powersave", fall back to the initial policy |
1099 | * value set by the driver. | |
1100 | */ | |
1101 | if (pol == CPUFREQ_POLICY_UNKNOWN) | |
1102 | pol = policy->policy; | |
ab05d97a | 1103 | } |
f5739cb0 RW |
1104 | if (pol != CPUFREQ_POLICY_PERFORMANCE && |
1105 | pol != CPUFREQ_POLICY_POWERSAVE) | |
1106 | return -ENODATA; | |
69030dd1 | 1107 | } |
ab05d97a | 1108 | |
8cc46ae5 VK |
1109 | ret = cpufreq_set_policy(policy, gov, pol); |
1110 | if (gov) | |
1111 | module_put(gov->owner); | |
1112 | ||
1113 | return ret; | |
909a694e DJ |
1114 | } |
1115 | ||
d9612a49 | 1116 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1117 | { |
9c0ebcf7 | 1118 | int ret = 0; |
fcf80582 | 1119 | |
bb29ae15 VK |
1120 | /* Has this CPU been taken care of already? */ |
1121 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1122 | return 0; | |
1123 | ||
49f18560 | 1124 | down_write(&policy->rwsem); |
45482c70 RW |
1125 | if (has_target()) |
1126 | cpufreq_stop_governor(policy); | |
fcf80582 | 1127 | |
fcf80582 | 1128 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1129 | |
9c0ebcf7 | 1130 | if (has_target()) { |
0a300767 | 1131 | ret = cpufreq_start_governor(policy); |
49f18560 | 1132 | if (ret) |
3de9bdeb | 1133 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1134 | } |
49f18560 VK |
1135 | up_write(&policy->rwsem); |
1136 | return ret; | |
fcf80582 | 1137 | } |
1da177e4 | 1138 | |
c57b25bd | 1139 | void refresh_frequency_limits(struct cpufreq_policy *policy) |
70a59fde | 1140 | { |
67d874c3 | 1141 | if (!policy_is_inactive(policy)) { |
67d874c3 | 1142 | pr_debug("updating policy for CPU %u\n", policy->cpu); |
70a59fde | 1143 | |
1e4f63ae | 1144 | cpufreq_set_policy(policy, policy->governor, policy->policy); |
67d874c3 | 1145 | } |
70a59fde | 1146 | } |
c57b25bd | 1147 | EXPORT_SYMBOL(refresh_frequency_limits); |
70a59fde | 1148 | |
11eb69b9 VK |
1149 | static void handle_update(struct work_struct *work) |
1150 | { | |
1151 | struct cpufreq_policy *policy = | |
1152 | container_of(work, struct cpufreq_policy, update); | |
70a59fde VK |
1153 | |
1154 | pr_debug("handle_update for cpu %u called\n", policy->cpu); | |
67d874c3 | 1155 | down_write(&policy->rwsem); |
70a59fde | 1156 | refresh_frequency_limits(policy); |
67d874c3 VK |
1157 | up_write(&policy->rwsem); |
1158 | } | |
1159 | ||
1160 | static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq, | |
1161 | void *data) | |
1162 | { | |
1163 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min); | |
1164 | ||
1165 | schedule_work(&policy->update); | |
1166 | return 0; | |
1167 | } | |
1168 | ||
1169 | static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq, | |
1170 | void *data) | |
1171 | { | |
1172 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max); | |
1173 | ||
1174 | schedule_work(&policy->update); | |
1175 | return 0; | |
1176 | } | |
1177 | ||
1178 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) | |
1179 | { | |
1180 | struct kobject *kobj; | |
1181 | struct completion *cmp; | |
1182 | ||
1183 | down_write(&policy->rwsem); | |
1184 | cpufreq_stats_free_table(policy); | |
1185 | kobj = &policy->kobj; | |
1186 | cmp = &policy->kobj_unregister; | |
1187 | up_write(&policy->rwsem); | |
1188 | kobject_put(kobj); | |
1189 | ||
1190 | /* | |
1191 | * We need to make sure that the underlying kobj is | |
1192 | * actually not referenced anymore by anybody before we | |
1193 | * proceed with unloading. | |
1194 | */ | |
1195 | pr_debug("waiting for dropping of refcount\n"); | |
1196 | wait_for_completion(cmp); | |
1197 | pr_debug("wait complete\n"); | |
fcf80582 | 1198 | } |
1da177e4 | 1199 | |
a34e63b1 | 1200 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1201 | { |
1202 | struct cpufreq_policy *policy; | |
67d874c3 | 1203 | struct device *dev = get_cpu_device(cpu); |
edd4a893 | 1204 | int ret; |
e9698cc5 | 1205 | |
67d874c3 VK |
1206 | if (!dev) |
1207 | return NULL; | |
1208 | ||
e9698cc5 SB |
1209 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1210 | if (!policy) | |
1211 | return NULL; | |
1212 | ||
1213 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1214 | goto err_free_policy; | |
1215 | ||
1216 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1217 | goto err_free_cpumask; | |
1218 | ||
559ed407 RW |
1219 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1220 | goto err_free_rcpumask; | |
1221 | ||
edd4a893 VK |
1222 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1223 | cpufreq_global_kobject, "policy%u", cpu); | |
1224 | if (ret) { | |
67d874c3 | 1225 | dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret); |
2acb9bda RW |
1226 | /* |
1227 | * The entire policy object will be freed below, but the extra | |
1228 | * memory allocated for the kobject name needs to be freed by | |
1229 | * releasing the kobject. | |
1230 | */ | |
4ebe36c9 | 1231 | kobject_put(&policy->kobj); |
edd4a893 VK |
1232 | goto err_free_real_cpus; |
1233 | } | |
1234 | ||
3000ce3c RW |
1235 | freq_constraints_init(&policy->constraints); |
1236 | ||
67d874c3 VK |
1237 | policy->nb_min.notifier_call = cpufreq_notifier_min; |
1238 | policy->nb_max.notifier_call = cpufreq_notifier_max; | |
1239 | ||
3000ce3c RW |
1240 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MIN, |
1241 | &policy->nb_min); | |
67d874c3 VK |
1242 | if (ret) { |
1243 | dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n", | |
1244 | ret, cpumask_pr_args(policy->cpus)); | |
1245 | goto err_kobj_remove; | |
1246 | } | |
1247 | ||
3000ce3c RW |
1248 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MAX, |
1249 | &policy->nb_max); | |
67d874c3 VK |
1250 | if (ret) { |
1251 | dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n", | |
1252 | ret, cpumask_pr_args(policy->cpus)); | |
1253 | goto err_min_qos_notifier; | |
1254 | } | |
1255 | ||
c88a1f8b | 1256 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1257 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1258 | spin_lock_init(&policy->transition_lock); |
1259 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1260 | init_completion(&policy->kobj_unregister); |
1261 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1262 | |
a34e63b1 | 1263 | policy->cpu = cpu; |
e9698cc5 SB |
1264 | return policy; |
1265 | ||
67d874c3 | 1266 | err_min_qos_notifier: |
3000ce3c RW |
1267 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, |
1268 | &policy->nb_min); | |
67d874c3 VK |
1269 | err_kobj_remove: |
1270 | cpufreq_policy_put_kobj(policy); | |
edd4a893 VK |
1271 | err_free_real_cpus: |
1272 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1273 | err_free_rcpumask: |
1274 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1275 | err_free_cpumask: |
1276 | free_cpumask_var(policy->cpus); | |
1277 | err_free_policy: | |
1278 | kfree(policy); | |
1279 | ||
1280 | return NULL; | |
1281 | } | |
1282 | ||
f9f41e3e | 1283 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1284 | { |
988bed09 VK |
1285 | unsigned long flags; |
1286 | int cpu; | |
1287 | ||
1288 | /* Remove policy from list */ | |
1289 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1290 | list_del(&policy->policy_list); | |
1291 | ||
1292 | for_each_cpu(cpu, policy->related_cpus) | |
1293 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1294 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1295 | ||
3000ce3c RW |
1296 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MAX, |
1297 | &policy->nb_max); | |
1298 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, | |
1299 | &policy->nb_min); | |
6a149036 | 1300 | |
6941051d SH |
1301 | /* Cancel any pending policy->update work before freeing the policy. */ |
1302 | cancel_work_sync(&policy->update); | |
6a149036 VK |
1303 | |
1304 | if (policy->max_freq_req) { | |
1305 | /* | |
1306 | * CPUFREQ_CREATE_POLICY notification is sent only after | |
1307 | * successfully adding max_freq_req request. | |
1308 | */ | |
1309 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1310 | CPUFREQ_REMOVE_POLICY, policy); | |
3000ce3c | 1311 | freq_qos_remove_request(policy->max_freq_req); |
6a149036 VK |
1312 | } |
1313 | ||
3000ce3c | 1314 | freq_qos_remove_request(policy->min_freq_req); |
18c49926 | 1315 | kfree(policy->min_freq_req); |
67d874c3 | 1316 | |
f9f41e3e | 1317 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1318 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1319 | free_cpumask_var(policy->related_cpus); |
1320 | free_cpumask_var(policy->cpus); | |
1321 | kfree(policy); | |
1322 | } | |
1323 | ||
0b275352 | 1324 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1325 | { |
7f0c020a | 1326 | struct cpufreq_policy *policy; |
194d99c7 | 1327 | bool new_policy; |
1da177e4 | 1328 | unsigned long flags; |
0b275352 RW |
1329 | unsigned int j; |
1330 | int ret; | |
87549141 | 1331 | |
0b275352 | 1332 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1333 | |
bb29ae15 | 1334 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1335 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1336 | if (policy) { |
9104bb26 | 1337 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1338 | if (!policy_is_inactive(policy)) |
d9612a49 | 1339 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1340 | |
11ce707e | 1341 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1342 | new_policy = false; |
11ce707e RW |
1343 | down_write(&policy->rwsem); |
1344 | policy->cpu = cpu; | |
1345 | policy->governor = NULL; | |
1346 | up_write(&policy->rwsem); | |
1347 | } else { | |
194d99c7 | 1348 | new_policy = true; |
a34e63b1 | 1349 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1350 | if (!policy) |
d4d854d6 | 1351 | return -ENOMEM; |
72368d12 | 1352 | } |
0d66b91e | 1353 | |
91a12e91 VK |
1354 | if (!new_policy && cpufreq_driver->online) { |
1355 | ret = cpufreq_driver->online(policy); | |
1356 | if (ret) { | |
1357 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1358 | __LINE__); | |
1359 | goto out_exit_policy; | |
1360 | } | |
1da177e4 | 1361 | |
91a12e91 VK |
1362 | /* Recover policy->cpus using related_cpus */ |
1363 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1364 | } else { | |
1365 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1366 | |
91a12e91 VK |
1367 | /* |
1368 | * Call driver. From then on the cpufreq must be able | |
1369 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1370 | */ | |
1371 | ret = cpufreq_driver->init(policy); | |
1372 | if (ret) { | |
1373 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1374 | __LINE__); | |
1375 | goto out_free_policy; | |
1376 | } | |
d417e069 | 1377 | |
91a12e91 VK |
1378 | ret = cpufreq_table_validate_and_sort(policy); |
1379 | if (ret) | |
1380 | goto out_exit_policy; | |
6d4e81ed | 1381 | |
4d1f3a5b | 1382 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1383 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1384 | } |
559ed407 | 1385 | |
91a12e91 | 1386 | down_write(&policy->rwsem); |
5a7e56a5 VK |
1387 | /* |
1388 | * affected cpus must always be the one, which are online. We aren't | |
1389 | * managing offline cpus here. | |
1390 | */ | |
1391 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1392 | ||
194d99c7 | 1393 | if (new_policy) { |
2f0ba790 | 1394 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1395 | per_cpu(cpufreq_cpu_data, j) = policy; |
2f0ba790 RW |
1396 | add_cpu_dev_symlink(policy, j); |
1397 | } | |
18c49926 VK |
1398 | |
1399 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1400 | GFP_KERNEL); | |
1401 | if (!policy->min_freq_req) | |
1402 | goto out_destroy_policy; | |
1403 | ||
3000ce3c RW |
1404 | ret = freq_qos_add_request(&policy->constraints, |
1405 | policy->min_freq_req, FREQ_QOS_MIN, | |
1406 | policy->min); | |
18c49926 VK |
1407 | if (ret < 0) { |
1408 | /* | |
3000ce3c | 1409 | * So we don't call freq_qos_remove_request() for an |
18c49926 VK |
1410 | * uninitialized request. |
1411 | */ | |
1412 | kfree(policy->min_freq_req); | |
1413 | policy->min_freq_req = NULL; | |
18c49926 VK |
1414 | goto out_destroy_policy; |
1415 | } | |
1416 | ||
1417 | /* | |
1418 | * This must be initialized right here to avoid calling | |
3000ce3c | 1419 | * freq_qos_remove_request() on uninitialized request in case |
18c49926 VK |
1420 | * of errors. |
1421 | */ | |
1422 | policy->max_freq_req = policy->min_freq_req + 1; | |
1423 | ||
3000ce3c RW |
1424 | ret = freq_qos_add_request(&policy->constraints, |
1425 | policy->max_freq_req, FREQ_QOS_MAX, | |
1426 | policy->max); | |
18c49926 VK |
1427 | if (ret < 0) { |
1428 | policy->max_freq_req = NULL; | |
18c49926 VK |
1429 | goto out_destroy_policy; |
1430 | } | |
6a149036 VK |
1431 | |
1432 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1433 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1434 | } |
652ed95d | 1435 | |
5ddc6d4e | 1436 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1437 | policy->cur = cpufreq_driver->get(policy->cpu); |
1438 | if (!policy->cur) { | |
1439 | pr_err("%s: ->get() failed\n", __func__); | |
d417e069 | 1440 | goto out_destroy_policy; |
da60ce9f VK |
1441 | } |
1442 | } | |
1443 | ||
d3916691 VK |
1444 | /* |
1445 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1446 | * frequency table present with cpufreq core. In such cases CPU might be | |
1447 | * unstable if it has to run on that frequency for long duration of time | |
1448 | * and so its better to set it to a frequency which is specified in | |
1449 | * freq-table. This also makes cpufreq stats inconsistent as | |
1450 | * cpufreq-stats would fail to register because current frequency of CPU | |
1451 | * isn't found in freq-table. | |
1452 | * | |
1453 | * Because we don't want this change to effect boot process badly, we go | |
1454 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1455 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1456 | * is initialized to zero). | |
1457 | * | |
1458 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1459 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1460 | * equal to target-freq. | |
1461 | */ | |
1462 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1463 | && has_target()) { | |
1464 | /* Are we running at unknown frequency ? */ | |
1465 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1466 | if (ret == -EINVAL) { | |
1467 | /* Warn user and fix it */ | |
1468 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1469 | __func__, policy->cpu, policy->cur); | |
1470 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1471 | CPUFREQ_RELATION_L); | |
1472 | ||
1473 | /* | |
1474 | * Reaching here after boot in a few seconds may not | |
1475 | * mean that system will remain stable at "unknown" | |
1476 | * frequency for longer duration. Hence, a BUG_ON(). | |
1477 | */ | |
1478 | BUG_ON(ret); | |
1479 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1480 | __func__, policy->cpu, policy->cur); | |
1481 | } | |
1482 | } | |
1483 | ||
194d99c7 | 1484 | if (new_policy) { |
d9612a49 | 1485 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1486 | if (ret) |
d417e069 | 1487 | goto out_destroy_policy; |
1aefc75b RW |
1488 | |
1489 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1490 | |
988bed09 VK |
1491 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1492 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1493 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1494 | } | |
9515f4d6 | 1495 | |
7f0fa40f VK |
1496 | ret = cpufreq_init_policy(policy); |
1497 | if (ret) { | |
1498 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1499 | __func__, cpu, ret); | |
d417e069 | 1500 | goto out_destroy_policy; |
08fd8c1c | 1501 | } |
e18f1682 | 1502 | |
4e97b631 | 1503 | up_write(&policy->rwsem); |
08fd8c1c | 1504 | |
038c5b3e | 1505 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1506 | |
7c45cf31 VK |
1507 | /* Callback for handling stuff after policy is ready */ |
1508 | if (cpufreq_driver->ready) | |
1509 | cpufreq_driver->ready(policy); | |
1510 | ||
bcc61569 | 1511 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1512 | policy->cdev = of_cpufreq_cooling_register(policy); |
1513 | ||
2d06d8c4 | 1514 | pr_debug("initialization complete\n"); |
87c32271 | 1515 | |
1da177e4 LT |
1516 | return 0; |
1517 | ||
d417e069 | 1518 | out_destroy_policy: |
b24b6478 VK |
1519 | for_each_cpu(j, policy->real_cpus) |
1520 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1521 | ||
7106e02b PB |
1522 | up_write(&policy->rwsem); |
1523 | ||
d417e069 | 1524 | out_exit_policy: |
da60ce9f VK |
1525 | if (cpufreq_driver->exit) |
1526 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1527 | |
8101f997 | 1528 | out_free_policy: |
f9f41e3e | 1529 | cpufreq_policy_free(policy); |
1da177e4 LT |
1530 | return ret; |
1531 | } | |
1532 | ||
0b275352 RW |
1533 | /** |
1534 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1535 | * @dev: CPU device. | |
1536 | * @sif: Subsystem interface structure pointer (not used) | |
1537 | */ | |
1538 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1539 | { | |
a794d613 | 1540 | struct cpufreq_policy *policy; |
0b275352 | 1541 | unsigned cpu = dev->id; |
26619804 | 1542 | int ret; |
0b275352 RW |
1543 | |
1544 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1545 | ||
26619804 VK |
1546 | if (cpu_online(cpu)) { |
1547 | ret = cpufreq_online(cpu); | |
1548 | if (ret) | |
1549 | return ret; | |
1550 | } | |
0b275352 | 1551 | |
26619804 | 1552 | /* Create sysfs link on CPU registration */ |
a794d613 | 1553 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 RW |
1554 | if (policy) |
1555 | add_cpu_dev_symlink(policy, cpu); | |
26619804 | 1556 | |
2f0ba790 | 1557 | return 0; |
1da177e4 LT |
1558 | } |
1559 | ||
27622b06 | 1560 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1561 | { |
3a3e9e06 | 1562 | struct cpufreq_policy *policy; |
69cee714 | 1563 | int ret; |
1da177e4 | 1564 | |
b8eed8af | 1565 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1566 | |
988bed09 | 1567 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1568 | if (!policy) { |
b8eed8af | 1569 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1570 | return 0; |
1da177e4 | 1571 | } |
1da177e4 | 1572 | |
49f18560 | 1573 | down_write(&policy->rwsem); |
45482c70 RW |
1574 | if (has_target()) |
1575 | cpufreq_stop_governor(policy); | |
1da177e4 | 1576 | |
9591becb | 1577 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1578 | |
9591becb VK |
1579 | if (policy_is_inactive(policy)) { |
1580 | if (has_target()) | |
1581 | strncpy(policy->last_governor, policy->governor->name, | |
1582 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1583 | else |
1584 | policy->last_policy = policy->policy; | |
9591becb VK |
1585 | } else if (cpu == policy->cpu) { |
1586 | /* Nominate new CPU */ | |
1587 | policy->cpu = cpumask_any(policy->cpus); | |
1588 | } | |
084f3493 | 1589 | |
9591becb VK |
1590 | /* Start governor again for active policy */ |
1591 | if (!policy_is_inactive(policy)) { | |
1592 | if (has_target()) { | |
0a300767 | 1593 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1594 | if (ret) |
1595 | pr_err("%s: Failed to start governor\n", __func__); | |
1596 | } | |
cedb70af | 1597 | |
49f18560 | 1598 | goto unlock; |
cedb70af SB |
1599 | } |
1600 | ||
bcc61569 | 1601 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1602 | cpufreq_cooling_unregister(policy->cdev); |
1603 | policy->cdev = NULL; | |
1604 | } | |
1605 | ||
69cee714 VK |
1606 | if (cpufreq_driver->stop_cpu) |
1607 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1608 | |
36be3418 RW |
1609 | if (has_target()) |
1610 | cpufreq_exit_governor(policy); | |
1da177e4 | 1611 | |
87549141 | 1612 | /* |
91a12e91 VK |
1613 | * Perform the ->offline() during light-weight tear-down, as |
1614 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1615 | */ |
91a12e91 VK |
1616 | if (cpufreq_driver->offline) { |
1617 | cpufreq_driver->offline(policy); | |
1618 | } else if (cpufreq_driver->exit) { | |
87549141 | 1619 | cpufreq_driver->exit(policy); |
55582bcc SP |
1620 | policy->freq_table = NULL; |
1621 | } | |
49f18560 VK |
1622 | |
1623 | unlock: | |
1624 | up_write(&policy->rwsem); | |
27622b06 | 1625 | return 0; |
1da177e4 LT |
1626 | } |
1627 | ||
a9909c21 | 1628 | /* |
27a862e9 | 1629 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1630 | * |
1631 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1632 | */ |
71db87ba | 1633 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1634 | { |
8a25a2fd | 1635 | unsigned int cpu = dev->id; |
559ed407 | 1636 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1637 | |
559ed407 | 1638 | if (!policy) |
1af115d6 | 1639 | return; |
87549141 | 1640 | |
69cee714 VK |
1641 | if (cpu_online(cpu)) |
1642 | cpufreq_offline(cpu); | |
87549141 | 1643 | |
559ed407 | 1644 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1645 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1646 | |
91a12e91 VK |
1647 | if (cpumask_empty(policy->real_cpus)) { |
1648 | /* We did light-weight exit earlier, do full tear down now */ | |
1649 | if (cpufreq_driver->offline) | |
1650 | cpufreq_driver->exit(policy); | |
1651 | ||
f9f41e3e | 1652 | cpufreq_policy_free(policy); |
91a12e91 | 1653 | } |
5a01f2e8 VP |
1654 | } |
1655 | ||
1da177e4 | 1656 | /** |
bb176f7d VK |
1657 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1658 | * in deep trouble. | |
a1e1dc41 | 1659 | * @policy: policy managing CPUs |
1da177e4 LT |
1660 | * @new_freq: CPU frequency the CPU actually runs at |
1661 | * | |
29464f28 DJ |
1662 | * We adjust to current frequency first, and need to clean up later. |
1663 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1664 | */ |
a1e1dc41 | 1665 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1666 | unsigned int new_freq) |
1da177e4 LT |
1667 | { |
1668 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1669 | |
e837f9b5 | 1670 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1671 | policy->cur, new_freq); |
1da177e4 | 1672 | |
a1e1dc41 | 1673 | freqs.old = policy->cur; |
1da177e4 | 1674 | freqs.new = new_freq; |
b43a7ffb | 1675 | |
8fec051e VK |
1676 | cpufreq_freq_transition_begin(policy, &freqs); |
1677 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1678 | } |
1679 | ||
5980752e VK |
1680 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1681 | { | |
1682 | unsigned int new_freq; | |
1683 | ||
1684 | new_freq = cpufreq_driver->get(policy->cpu); | |
1685 | if (!new_freq) | |
1686 | return 0; | |
1687 | ||
1688 | /* | |
1689 | * If fast frequency switching is used with the given policy, the check | |
1690 | * against policy->cur is pointless, so skip it in that case. | |
1691 | */ | |
1692 | if (policy->fast_switch_enabled || !has_target()) | |
1693 | return new_freq; | |
1694 | ||
1695 | if (policy->cur != new_freq) { | |
1696 | cpufreq_out_of_sync(policy, new_freq); | |
1697 | if (update) | |
1698 | schedule_work(&policy->update); | |
1699 | } | |
1700 | ||
1701 | return new_freq; | |
1702 | } | |
1703 | ||
32ee8c3e | 1704 | /** |
4ab70df4 | 1705 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1706 | * @cpu: CPU number |
1707 | * | |
1708 | * This is the last known freq, without actually getting it from the driver. | |
1709 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1710 | */ | |
1711 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1712 | { | |
9e21ba8b | 1713 | struct cpufreq_policy *policy; |
e08f5f5b | 1714 | unsigned int ret_freq = 0; |
c75361c0 | 1715 | unsigned long flags; |
95235ca2 | 1716 | |
c75361c0 RC |
1717 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1718 | ||
1719 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1720 | ret_freq = cpufreq_driver->get(cpu); | |
1721 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1722 | return ret_freq; | |
1723 | } | |
1724 | ||
1725 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1726 | |
1727 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1728 | if (policy) { |
e08f5f5b | 1729 | ret_freq = policy->cur; |
95235ca2 VP |
1730 | cpufreq_cpu_put(policy); |
1731 | } | |
1732 | ||
4d34a67d | 1733 | return ret_freq; |
95235ca2 VP |
1734 | } |
1735 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1736 | ||
3d737108 JB |
1737 | /** |
1738 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1739 | * @cpu: CPU number | |
1740 | * | |
1741 | * Just return the max possible frequency for a given CPU. | |
1742 | */ | |
1743 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1744 | { | |
1745 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1746 | unsigned int ret_freq = 0; | |
1747 | ||
1748 | if (policy) { | |
1749 | ret_freq = policy->max; | |
1750 | cpufreq_cpu_put(policy); | |
1751 | } | |
1752 | ||
1753 | return ret_freq; | |
1754 | } | |
1755 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1756 | ||
bbce8eaa IV |
1757 | /** |
1758 | * cpufreq_get_hw_max_freq - get the max hardware frequency of the CPU | |
1759 | * @cpu: CPU number | |
1760 | * | |
1761 | * The default return value is the max_freq field of cpuinfo. | |
1762 | */ | |
1763 | __weak unsigned int cpufreq_get_hw_max_freq(unsigned int cpu) | |
1764 | { | |
1765 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1766 | unsigned int ret_freq = 0; | |
1767 | ||
1768 | if (policy) { | |
1769 | ret_freq = policy->cpuinfo.max_freq; | |
1770 | cpufreq_cpu_put(policy); | |
1771 | } | |
1772 | ||
1773 | return ret_freq; | |
1774 | } | |
1775 | EXPORT_SYMBOL(cpufreq_get_hw_max_freq); | |
1776 | ||
d92d50a4 | 1777 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1778 | { |
4db7c34c | 1779 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1780 | return 0; |
1da177e4 | 1781 | |
5980752e | 1782 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1783 | } |
1da177e4 | 1784 | |
5a01f2e8 VP |
1785 | /** |
1786 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1787 | * @cpu: CPU number | |
1788 | * | |
1789 | * Get the CPU current (static) CPU frequency | |
1790 | */ | |
1791 | unsigned int cpufreq_get(unsigned int cpu) | |
1792 | { | |
999976e0 | 1793 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1794 | unsigned int ret_freq = 0; |
5a01f2e8 | 1795 | |
999976e0 AP |
1796 | if (policy) { |
1797 | down_read(&policy->rwsem); | |
4db7c34c YH |
1798 | if (cpufreq_driver->get) |
1799 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1800 | up_read(&policy->rwsem); |
5a01f2e8 | 1801 | |
999976e0 AP |
1802 | cpufreq_cpu_put(policy); |
1803 | } | |
6eed9404 | 1804 | |
4d34a67d | 1805 | return ret_freq; |
1da177e4 LT |
1806 | } |
1807 | EXPORT_SYMBOL(cpufreq_get); | |
1808 | ||
8a25a2fd KS |
1809 | static struct subsys_interface cpufreq_interface = { |
1810 | .name = "cpufreq", | |
1811 | .subsys = &cpu_subsys, | |
1812 | .add_dev = cpufreq_add_dev, | |
1813 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1814 | }; |
1815 | ||
e28867ea VK |
1816 | /* |
1817 | * In case platform wants some specific frequency to be configured | |
1818 | * during suspend.. | |
1819 | */ | |
1820 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1821 | { | |
1822 | int ret; | |
1823 | ||
1824 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1825 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1826 | return 0; | |
e28867ea VK |
1827 | } |
1828 | ||
1829 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1830 | policy->suspend_freq); | |
1831 | ||
1832 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1833 | CPUFREQ_RELATION_H); | |
1834 | if (ret) | |
1835 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1836 | __func__, policy->suspend_freq, ret); | |
1837 | ||
1838 | return ret; | |
1839 | } | |
1840 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1841 | ||
42d4dc3f | 1842 | /** |
2f0aea93 | 1843 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1844 | * |
2f0aea93 VK |
1845 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1846 | * as some platforms can't change frequency after this point in suspend cycle. | |
1847 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1848 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1849 | */ |
2f0aea93 | 1850 | void cpufreq_suspend(void) |
42d4dc3f | 1851 | { |
3a3e9e06 | 1852 | struct cpufreq_policy *policy; |
42d4dc3f | 1853 | |
2f0aea93 VK |
1854 | if (!cpufreq_driver) |
1855 | return; | |
42d4dc3f | 1856 | |
ba41e1bc | 1857 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1858 | goto suspend; |
42d4dc3f | 1859 | |
2f0aea93 VK |
1860 | pr_debug("%s: Suspending Governors\n", __func__); |
1861 | ||
f963735a | 1862 | for_each_active_policy(policy) { |
ba41e1bc RW |
1863 | if (has_target()) { |
1864 | down_write(&policy->rwsem); | |
45482c70 | 1865 | cpufreq_stop_governor(policy); |
ba41e1bc | 1866 | up_write(&policy->rwsem); |
ba41e1bc RW |
1867 | } |
1868 | ||
1869 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1870 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1871 | cpufreq_driver->name); | |
42d4dc3f | 1872 | } |
b1b12bab VK |
1873 | |
1874 | suspend: | |
1875 | cpufreq_suspended = true; | |
42d4dc3f BH |
1876 | } |
1877 | ||
1da177e4 | 1878 | /** |
2f0aea93 | 1879 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1880 | * |
2f0aea93 VK |
1881 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1882 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1883 | */ |
2f0aea93 | 1884 | void cpufreq_resume(void) |
1da177e4 | 1885 | { |
3a3e9e06 | 1886 | struct cpufreq_policy *policy; |
49f18560 | 1887 | int ret; |
1da177e4 | 1888 | |
2f0aea93 | 1889 | if (!cpufreq_driver) |
703cbaa6 BY |
1890 | return; |
1891 | ||
1892 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1893 | return; |
1da177e4 | 1894 | |
8e30444e LT |
1895 | cpufreq_suspended = false; |
1896 | ||
ba41e1bc | 1897 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1898 | return; |
1da177e4 | 1899 | |
2f0aea93 | 1900 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1901 | |
f963735a | 1902 | for_each_active_policy(policy) { |
49f18560 | 1903 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1904 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1905 | policy); | |
ba41e1bc | 1906 | } else if (has_target()) { |
49f18560 | 1907 | down_write(&policy->rwsem); |
0a300767 | 1908 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1909 | up_write(&policy->rwsem); |
1910 | ||
1911 | if (ret) | |
1912 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1913 | __func__, policy); | |
1914 | } | |
2f0aea93 VK |
1915 | } |
1916 | } | |
1da177e4 | 1917 | |
9d95046e BP |
1918 | /** |
1919 | * cpufreq_get_current_driver - return current driver's name | |
1920 | * | |
1921 | * Return the name string of the currently loaded cpufreq driver | |
1922 | * or NULL, if none. | |
1923 | */ | |
1924 | const char *cpufreq_get_current_driver(void) | |
1925 | { | |
1c3d85dd RW |
1926 | if (cpufreq_driver) |
1927 | return cpufreq_driver->name; | |
1928 | ||
1929 | return NULL; | |
9d95046e BP |
1930 | } |
1931 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1932 | |
51315cdf TP |
1933 | /** |
1934 | * cpufreq_get_driver_data - return current driver data | |
1935 | * | |
1936 | * Return the private data of the currently loaded cpufreq | |
1937 | * driver, or NULL if no cpufreq driver is loaded. | |
1938 | */ | |
1939 | void *cpufreq_get_driver_data(void) | |
1940 | { | |
1941 | if (cpufreq_driver) | |
1942 | return cpufreq_driver->driver_data; | |
1943 | ||
1944 | return NULL; | |
1945 | } | |
1946 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1947 | ||
1da177e4 LT |
1948 | /********************************************************************* |
1949 | * NOTIFIER LISTS INTERFACE * | |
1950 | *********************************************************************/ | |
1951 | ||
1952 | /** | |
1953 | * cpufreq_register_notifier - register a driver with cpufreq | |
1954 | * @nb: notifier function to register | |
1955 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1956 | * | |
32ee8c3e | 1957 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1958 | * are notified about clock rate changes (once before and once after |
1959 | * the transition), or a list of drivers that are notified about | |
1960 | * changes in cpufreq policy. | |
1961 | * | |
1962 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1963 | * blocking_notifier_chain_register. |
1da177e4 LT |
1964 | */ |
1965 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1966 | { | |
1967 | int ret; | |
1968 | ||
d5aaffa9 DB |
1969 | if (cpufreq_disabled()) |
1970 | return -EINVAL; | |
1971 | ||
1da177e4 LT |
1972 | switch (list) { |
1973 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1974 | mutex_lock(&cpufreq_fast_switch_lock); |
1975 | ||
1976 | if (cpufreq_fast_switch_count > 0) { | |
1977 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1978 | return -EBUSY; | |
1979 | } | |
b4dfdbb3 | 1980 | ret = srcu_notifier_chain_register( |
e041c683 | 1981 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1982 | if (!ret) |
1983 | cpufreq_fast_switch_count--; | |
1984 | ||
1985 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1986 | break; |
1987 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1988 | ret = blocking_notifier_chain_register( |
1989 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1990 | break; |
1991 | default: | |
1992 | ret = -EINVAL; | |
1993 | } | |
1da177e4 LT |
1994 | |
1995 | return ret; | |
1996 | } | |
1997 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1998 | ||
1da177e4 LT |
1999 | /** |
2000 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
2001 | * @nb: notifier block to be unregistered | |
bb176f7d | 2002 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
2003 | * |
2004 | * Remove a driver from the CPU frequency notifier list. | |
2005 | * | |
2006 | * This function may sleep, and has the same return conditions as | |
e041c683 | 2007 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
2008 | */ |
2009 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
2010 | { | |
2011 | int ret; | |
2012 | ||
d5aaffa9 DB |
2013 | if (cpufreq_disabled()) |
2014 | return -EINVAL; | |
2015 | ||
1da177e4 LT |
2016 | switch (list) { |
2017 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
2018 | mutex_lock(&cpufreq_fast_switch_lock); |
2019 | ||
b4dfdbb3 | 2020 | ret = srcu_notifier_chain_unregister( |
e041c683 | 2021 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
2022 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
2023 | cpufreq_fast_switch_count++; | |
2024 | ||
2025 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
2026 | break; |
2027 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
2028 | ret = blocking_notifier_chain_unregister( |
2029 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
2030 | break; |
2031 | default: | |
2032 | ret = -EINVAL; | |
2033 | } | |
1da177e4 LT |
2034 | |
2035 | return ret; | |
2036 | } | |
2037 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
2038 | ||
2039 | ||
2040 | /********************************************************************* | |
2041 | * GOVERNORS * | |
2042 | *********************************************************************/ | |
2043 | ||
b7898fda RW |
2044 | /** |
2045 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
2046 | * @policy: cpufreq policy to switch the frequency for. | |
2047 | * @target_freq: New frequency to set (may be approximate). | |
2048 | * | |
2049 | * Carry out a fast frequency switch without sleeping. | |
2050 | * | |
2051 | * The driver's ->fast_switch() callback invoked by this function must be | |
2052 | * suitable for being called from within RCU-sched read-side critical sections | |
2053 | * and it is expected to select the minimum available frequency greater than or | |
2054 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2055 | * | |
2056 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2057 | * | |
2058 | * Governors calling this function must guarantee that it will never be invoked | |
2059 | * twice in parallel for the same policy and that it will never be called in | |
2060 | * parallel with either ->target() or ->target_index() for the same policy. | |
2061 | * | |
209887e6 VK |
2062 | * Returns the actual frequency set for the CPU. |
2063 | * | |
2064 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2065 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2066 | */ |
2067 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2068 | unsigned int target_freq) | |
2069 | { | |
1a0419b0 IV |
2070 | unsigned int freq; |
2071 | ||
b9af6948 | 2072 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
1a0419b0 IV |
2073 | freq = cpufreq_driver->fast_switch(policy, target_freq); |
2074 | ||
96f60cdd VK |
2075 | if (!freq) |
2076 | return 0; | |
2077 | ||
1a0419b0 IV |
2078 | arch_set_freq_scale(policy->related_cpus, freq, |
2079 | policy->cpuinfo.max_freq); | |
96f60cdd | 2080 | cpufreq_stats_record_transition(policy, freq); |
b7898fda | 2081 | |
1a0419b0 | 2082 | return freq; |
b7898fda RW |
2083 | } |
2084 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2085 | ||
1c03a2d0 VK |
2086 | /* Must set freqs->new to intermediate frequency */ |
2087 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2088 | struct cpufreq_freqs *freqs, int index) | |
2089 | { | |
2090 | int ret; | |
2091 | ||
2092 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2093 | ||
2094 | /* We don't need to switch to intermediate freq */ | |
2095 | if (!freqs->new) | |
2096 | return 0; | |
2097 | ||
2098 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2099 | __func__, policy->cpu, freqs->old, freqs->new); | |
2100 | ||
2101 | cpufreq_freq_transition_begin(policy, freqs); | |
2102 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2103 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2104 | ||
2105 | if (ret) | |
2106 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2107 | __func__, ret); | |
2108 | ||
2109 | return ret; | |
2110 | } | |
2111 | ||
23727845 | 2112 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2113 | { |
1c03a2d0 VK |
2114 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
2115 | unsigned int intermediate_freq = 0; | |
23727845 | 2116 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2117 | int retval = -EINVAL; |
2118 | bool notify; | |
2119 | ||
23727845 VK |
2120 | if (newfreq == policy->cur) |
2121 | return 0; | |
2122 | ||
8d65775d | 2123 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2124 | if (notify) { |
1c03a2d0 VK |
2125 | /* Handle switching to intermediate frequency */ |
2126 | if (cpufreq_driver->get_intermediate) { | |
2127 | retval = __target_intermediate(policy, &freqs, index); | |
2128 | if (retval) | |
2129 | return retval; | |
2130 | ||
2131 | intermediate_freq = freqs.new; | |
2132 | /* Set old freq to intermediate */ | |
2133 | if (intermediate_freq) | |
2134 | freqs.old = freqs.new; | |
2135 | } | |
8d65775d | 2136 | |
23727845 | 2137 | freqs.new = newfreq; |
8d65775d VK |
2138 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2139 | __func__, policy->cpu, freqs.old, freqs.new); | |
2140 | ||
2141 | cpufreq_freq_transition_begin(policy, &freqs); | |
2142 | } | |
2143 | ||
2144 | retval = cpufreq_driver->target_index(policy, index); | |
2145 | if (retval) | |
2146 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2147 | retval); | |
2148 | ||
1c03a2d0 | 2149 | if (notify) { |
8d65775d VK |
2150 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2151 | ||
1c03a2d0 VK |
2152 | /* |
2153 | * Failed after setting to intermediate freq? Driver should have | |
2154 | * reverted back to initial frequency and so should we. Check | |
2155 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2156 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2157 | */ |
2158 | if (unlikely(retval && intermediate_freq)) { | |
2159 | freqs.old = intermediate_freq; | |
2160 | freqs.new = policy->restore_freq; | |
2161 | cpufreq_freq_transition_begin(policy, &freqs); | |
2162 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2163 | } | |
2164 | } | |
2165 | ||
8d65775d VK |
2166 | return retval; |
2167 | } | |
2168 | ||
1da177e4 LT |
2169 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2170 | unsigned int target_freq, | |
2171 | unsigned int relation) | |
2172 | { | |
7249924e | 2173 | unsigned int old_target_freq = target_freq; |
d218ed77 | 2174 | int index; |
c32b6b8e | 2175 | |
a7b422cd KRW |
2176 | if (cpufreq_disabled()) |
2177 | return -ENODEV; | |
2178 | ||
7249924e | 2179 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 2180 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
2181 | |
2182 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2183 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2184 | |
9c0ebcf7 VK |
2185 | /* |
2186 | * This might look like a redundant call as we are checking it again | |
2187 | * after finding index. But it is left intentionally for cases where | |
2188 | * exactly same freq is called again and so we can save on few function | |
2189 | * calls. | |
2190 | */ | |
5a1c0228 VK |
2191 | if (target_freq == policy->cur) |
2192 | return 0; | |
2193 | ||
1c03a2d0 VK |
2194 | /* Save last value to restore later on errors */ |
2195 | policy->restore_freq = policy->cur; | |
2196 | ||
1c3d85dd | 2197 | if (cpufreq_driver->target) |
6019d23a | 2198 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 2199 | |
6019d23a RW |
2200 | if (!cpufreq_driver->target_index) |
2201 | return -EINVAL; | |
9c0ebcf7 | 2202 | |
d218ed77 | 2203 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 2204 | |
23727845 | 2205 | return __target_index(policy, index); |
1da177e4 LT |
2206 | } |
2207 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2208 | ||
1da177e4 LT |
2209 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2210 | unsigned int target_freq, | |
2211 | unsigned int relation) | |
2212 | { | |
62c23a89 | 2213 | int ret; |
1da177e4 | 2214 | |
ad7722da | 2215 | down_write(&policy->rwsem); |
1da177e4 LT |
2216 | |
2217 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2218 | ||
ad7722da | 2219 | up_write(&policy->rwsem); |
1da177e4 | 2220 | |
1da177e4 LT |
2221 | return ret; |
2222 | } | |
2223 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2224 | ||
de1df26b RW |
2225 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2226 | { | |
2227 | return NULL; | |
2228 | } | |
2229 | ||
a92604b4 | 2230 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2231 | { |
cc993cab | 2232 | int ret; |
6afde10c | 2233 | |
2f0aea93 VK |
2234 | /* Don't start any governor operations if we are entering suspend */ |
2235 | if (cpufreq_suspended) | |
2236 | return 0; | |
cb57720b EZ |
2237 | /* |
2238 | * Governor might not be initiated here if ACPI _PPC changed | |
2239 | * notification happened, so check it. | |
2240 | */ | |
2241 | if (!policy->governor) | |
2242 | return -EINVAL; | |
2f0aea93 | 2243 | |
ed4676e2 VK |
2244 | /* Platform doesn't want dynamic frequency switching ? */ |
2245 | if (policy->governor->dynamic_switching && | |
fc4c709f | 2246 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2247 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2248 | ||
2249 | if (gov) { | |
fe829ed8 | 2250 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2251 | policy->governor->name, gov->name); |
6afde10c | 2252 | policy->governor = gov; |
de1df26b RW |
2253 | } else { |
2254 | return -EINVAL; | |
6afde10c | 2255 | } |
1c256245 | 2256 | } |
1da177e4 | 2257 | |
a92604b4 RW |
2258 | if (!try_module_get(policy->governor->owner)) |
2259 | return -EINVAL; | |
95731ebb | 2260 | |
a92604b4 | 2261 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2262 | |
e788892b RW |
2263 | if (policy->governor->init) { |
2264 | ret = policy->governor->init(policy); | |
2265 | if (ret) { | |
36be3418 | 2266 | module_put(policy->governor->owner); |
e788892b RW |
2267 | return ret; |
2268 | } | |
36be3418 | 2269 | } |
1da177e4 | 2270 | |
a92604b4 RW |
2271 | return 0; |
2272 | } | |
2273 | ||
2274 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2275 | { | |
2276 | if (cpufreq_suspended || !policy->governor) | |
2277 | return; | |
2278 | ||
2279 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2280 | ||
e788892b RW |
2281 | if (policy->governor->exit) |
2282 | policy->governor->exit(policy); | |
a92604b4 | 2283 | |
a92604b4 | 2284 | module_put(policy->governor->owner); |
1da177e4 LT |
2285 | } |
2286 | ||
f6ebbcf0 | 2287 | int cpufreq_start_governor(struct cpufreq_policy *policy) |
0a300767 RW |
2288 | { |
2289 | int ret; | |
2290 | ||
a92604b4 RW |
2291 | if (cpufreq_suspended) |
2292 | return 0; | |
2293 | ||
2294 | if (!policy->governor) | |
2295 | return -EINVAL; | |
2296 | ||
2297 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2298 | ||
407d0fff | 2299 | if (cpufreq_driver->get) |
5980752e | 2300 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2301 | |
e788892b RW |
2302 | if (policy->governor->start) { |
2303 | ret = policy->governor->start(policy); | |
2304 | if (ret) | |
2305 | return ret; | |
2306 | } | |
2307 | ||
2308 | if (policy->governor->limits) | |
2309 | policy->governor->limits(policy); | |
d6ff44d6 | 2310 | |
d6ff44d6 | 2311 | return 0; |
0a300767 RW |
2312 | } |
2313 | ||
f6ebbcf0 | 2314 | void cpufreq_stop_governor(struct cpufreq_policy *policy) |
a92604b4 RW |
2315 | { |
2316 | if (cpufreq_suspended || !policy->governor) | |
2317 | return; | |
2318 | ||
2319 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2320 | ||
e788892b RW |
2321 | if (policy->governor->stop) |
2322 | policy->governor->stop(policy); | |
a92604b4 RW |
2323 | } |
2324 | ||
2325 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2326 | { | |
2327 | if (cpufreq_suspended || !policy->governor) | |
2328 | return; | |
2329 | ||
2330 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2331 | ||
e788892b RW |
2332 | if (policy->governor->limits) |
2333 | policy->governor->limits(policy); | |
0a300767 RW |
2334 | } |
2335 | ||
1da177e4 LT |
2336 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2337 | { | |
3bcb09a3 | 2338 | int err; |
1da177e4 LT |
2339 | |
2340 | if (!governor) | |
2341 | return -EINVAL; | |
2342 | ||
a7b422cd KRW |
2343 | if (cpufreq_disabled()) |
2344 | return -ENODEV; | |
2345 | ||
3fc54d37 | 2346 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2347 | |
3bcb09a3 | 2348 | err = -EBUSY; |
42f91fa1 | 2349 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2350 | err = 0; |
2351 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2352 | } |
1da177e4 | 2353 | |
32ee8c3e | 2354 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2355 | return err; |
1da177e4 LT |
2356 | } |
2357 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2358 | ||
1da177e4 LT |
2359 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2360 | { | |
4573237b VK |
2361 | struct cpufreq_policy *policy; |
2362 | unsigned long flags; | |
90e41bac | 2363 | |
1da177e4 LT |
2364 | if (!governor) |
2365 | return; | |
2366 | ||
a7b422cd KRW |
2367 | if (cpufreq_disabled()) |
2368 | return; | |
2369 | ||
4573237b VK |
2370 | /* clear last_governor for all inactive policies */ |
2371 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2372 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2373 | if (!strcmp(policy->last_governor, governor->name)) { |
2374 | policy->governor = NULL; | |
4573237b | 2375 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2376 | } |
90e41bac | 2377 | } |
4573237b | 2378 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2379 | |
3fc54d37 | 2380 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2381 | list_del(&governor->governor_list); |
3fc54d37 | 2382 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2383 | } |
2384 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2385 | ||
2386 | ||
1da177e4 LT |
2387 | /********************************************************************* |
2388 | * POLICY INTERFACE * | |
2389 | *********************************************************************/ | |
2390 | ||
2391 | /** | |
2392 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2393 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2394 | * is written | |
a9909c21 | 2395 | * @cpu: CPU to find the policy for |
1da177e4 LT |
2396 | * |
2397 | * Reads the current cpufreq policy. | |
2398 | */ | |
2399 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2400 | { | |
2401 | struct cpufreq_policy *cpu_policy; | |
2402 | if (!policy) | |
2403 | return -EINVAL; | |
2404 | ||
2405 | cpu_policy = cpufreq_cpu_get(cpu); | |
2406 | if (!cpu_policy) | |
2407 | return -EINVAL; | |
2408 | ||
d5b73cd8 | 2409 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2410 | |
2411 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2412 | return 0; |
2413 | } | |
2414 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2415 | ||
a0dbb819 RW |
2416 | /** |
2417 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2418 | * @policy: Policy object to modify. | |
1e4f63ae RW |
2419 | * @new_gov: Policy governor pointer. |
2420 | * @new_pol: Policy value (for drivers with built-in governors). | |
a0dbb819 | 2421 | * |
1e4f63ae RW |
2422 | * Invoke the cpufreq driver's ->verify() callback to sanity-check the frequency |
2423 | * limits to be set for the policy, update @policy with the verified limits | |
2424 | * values and either invoke the driver's ->setpolicy() callback (if present) or | |
2425 | * carry out a governor update for @policy. That is, run the current governor's | |
2426 | * ->limits() callback (if @new_gov points to the same object as the one in | |
2427 | * @policy) or replace the governor for @policy with @new_gov. | |
a0dbb819 RW |
2428 | * |
2429 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2430 | */ |
1e4f63ae RW |
2431 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
2432 | struct cpufreq_governor *new_gov, | |
2433 | unsigned int new_pol) | |
1da177e4 | 2434 | { |
1e4f63ae | 2435 | struct cpufreq_policy_data new_data; |
d9a789c7 RW |
2436 | struct cpufreq_governor *old_gov; |
2437 | int ret; | |
1da177e4 | 2438 | |
1e4f63ae RW |
2439 | memcpy(&new_data.cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
2440 | new_data.freq_table = policy->freq_table; | |
2441 | new_data.cpu = policy->cpu; | |
fba9573b | 2442 | /* |
67d874c3 VK |
2443 | * PM QoS framework collects all the requests from users and provide us |
2444 | * the final aggregated value here. | |
2445 | */ | |
1e4f63ae RW |
2446 | new_data.min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); |
2447 | new_data.max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); | |
2448 | ||
2449 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", | |
2450 | new_data.cpu, new_data.min, new_data.max); | |
9c9a43ed | 2451 | |
737ffb27 VK |
2452 | /* |
2453 | * Verify that the CPU speed can be set within these limits and make sure | |
2454 | * that min <= max. | |
2455 | */ | |
1e4f63ae | 2456 | ret = cpufreq_driver->verify(&new_data); |
1da177e4 | 2457 | if (ret) |
d9a789c7 | 2458 | return ret; |
1da177e4 | 2459 | |
1e4f63ae RW |
2460 | policy->min = new_data.min; |
2461 | policy->max = new_data.max; | |
601b2185 | 2462 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2463 | |
e3c06236 SM |
2464 | policy->cached_target_freq = UINT_MAX; |
2465 | ||
2d06d8c4 | 2466 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2467 | policy->min, policy->max); |
1da177e4 | 2468 | |
1c3d85dd | 2469 | if (cpufreq_driver->setpolicy) { |
1e4f63ae | 2470 | policy->policy = new_pol; |
2d06d8c4 | 2471 | pr_debug("setting range\n"); |
167a38dc | 2472 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2473 | } |
1da177e4 | 2474 | |
1e4f63ae | 2475 | if (new_gov == policy->governor) { |
2bb4059e | 2476 | pr_debug("governor limits update\n"); |
a92604b4 | 2477 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2478 | return 0; |
0a300767 | 2479 | } |
7bd353a9 | 2480 | |
d9a789c7 RW |
2481 | pr_debug("governor switch\n"); |
2482 | ||
2483 | /* save old, working values */ | |
2484 | old_gov = policy->governor; | |
2485 | /* end old governor */ | |
2486 | if (old_gov) { | |
45482c70 | 2487 | cpufreq_stop_governor(policy); |
36be3418 | 2488 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2489 | } |
2490 | ||
d9a789c7 | 2491 | /* start new governor */ |
1e4f63ae | 2492 | policy->governor = new_gov; |
a92604b4 | 2493 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2494 | if (!ret) { |
0a300767 RW |
2495 | ret = cpufreq_start_governor(policy); |
2496 | if (!ret) { | |
2bb4059e | 2497 | pr_debug("governor change\n"); |
531b5c9f | 2498 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2499 | return 0; |
2500 | } | |
b7898fda | 2501 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2502 | } |
2503 | ||
2504 | /* new governor failed, so re-start old one */ | |
2505 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2506 | if (old_gov) { | |
2507 | policy->governor = old_gov; | |
a92604b4 | 2508 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2509 | policy->governor = NULL; |
2510 | else | |
0a300767 | 2511 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2512 | } |
2513 | ||
4bc384ae | 2514 | return ret; |
1da177e4 LT |
2515 | } |
2516 | ||
1da177e4 | 2517 | /** |
a0dbb819 RW |
2518 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2519 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2520 | * |
a0dbb819 | 2521 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2522 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2523 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2524 | * for the policy in question, among other things. | |
1da177e4 | 2525 | */ |
30248fef | 2526 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2527 | { |
540a3758 | 2528 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2529 | |
fefa8ff8 | 2530 | if (!policy) |
30248fef | 2531 | return; |
1da177e4 | 2532 | |
bb176f7d VK |
2533 | /* |
2534 | * BIOS might change freq behind our back | |
2535 | * -> ask driver for current freq and notify governors about a change | |
2536 | */ | |
5ddc6d4e | 2537 | if (cpufreq_driver->get && has_target() && |
5980752e | 2538 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2539 | goto unlock; |
30248fef | 2540 | |
70a59fde | 2541 | refresh_frequency_limits(policy); |
1da177e4 | 2542 | |
fefa8ff8 | 2543 | unlock: |
540a3758 | 2544 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2545 | } |
2546 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2547 | ||
5a25e3f7 RW |
2548 | /** |
2549 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2550 | * @cpu: CPU to update the policy limits for. | |
2551 | * | |
2552 | * Invoke the driver's ->update_limits callback if present or call | |
2553 | * cpufreq_update_policy() for @cpu. | |
2554 | */ | |
2555 | void cpufreq_update_limits(unsigned int cpu) | |
2556 | { | |
2557 | if (cpufreq_driver->update_limits) | |
2558 | cpufreq_driver->update_limits(cpu); | |
2559 | else | |
2560 | cpufreq_update_policy(cpu); | |
2561 | } | |
2562 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2563 | ||
6f19efc0 LM |
2564 | /********************************************************************* |
2565 | * BOOST * | |
2566 | *********************************************************************/ | |
cf6fada7 | 2567 | static int cpufreq_boost_set_sw(struct cpufreq_policy *policy, int state) |
6f19efc0 | 2568 | { |
cf6fada7 | 2569 | int ret; |
49f18560 | 2570 | |
cf6fada7 XW |
2571 | if (!policy->freq_table) |
2572 | return -ENXIO; | |
f8bfc116 | 2573 | |
cf6fada7 XW |
2574 | ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table); |
2575 | if (ret) { | |
2576 | pr_err("%s: Policy frequency update failed\n", __func__); | |
2577 | return ret; | |
6f19efc0 LM |
2578 | } |
2579 | ||
cf6fada7 XW |
2580 | ret = freq_qos_update_request(policy->max_freq_req, policy->max); |
2581 | if (ret < 0) | |
2582 | return ret; | |
2583 | ||
552abb88 | 2584 | return 0; |
6f19efc0 LM |
2585 | } |
2586 | ||
2587 | int cpufreq_boost_trigger_state(int state) | |
2588 | { | |
cf6fada7 | 2589 | struct cpufreq_policy *policy; |
6f19efc0 LM |
2590 | unsigned long flags; |
2591 | int ret = 0; | |
2592 | ||
2593 | if (cpufreq_driver->boost_enabled == state) | |
2594 | return 0; | |
2595 | ||
2596 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2597 | cpufreq_driver->boost_enabled = state; | |
2598 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2599 | ||
cf6fada7 XW |
2600 | get_online_cpus(); |
2601 | for_each_active_policy(policy) { | |
2602 | ret = cpufreq_driver->set_boost(policy, state); | |
2603 | if (ret) | |
2604 | goto err_reset_state; | |
6f19efc0 | 2605 | } |
cf6fada7 XW |
2606 | put_online_cpus(); |
2607 | ||
2608 | return 0; | |
2609 | ||
2610 | err_reset_state: | |
2611 | put_online_cpus(); | |
2612 | ||
2613 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2614 | cpufreq_driver->boost_enabled = !state; | |
2615 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2616 | ||
2617 | pr_err("%s: Cannot %s BOOST\n", | |
2618 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2619 | |
2620 | return ret; | |
2621 | } | |
2622 | ||
41669da0 | 2623 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2624 | { |
89f98d7e | 2625 | return cpufreq_driver->set_boost; |
6f19efc0 | 2626 | } |
6f19efc0 | 2627 | |
44139ed4 VK |
2628 | static int create_boost_sysfs_file(void) |
2629 | { | |
2630 | int ret; | |
2631 | ||
c82bd444 | 2632 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2633 | if (ret) |
2634 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2635 | __func__); | |
2636 | ||
2637 | return ret; | |
2638 | } | |
2639 | ||
2640 | static void remove_boost_sysfs_file(void) | |
2641 | { | |
2642 | if (cpufreq_boost_supported()) | |
c82bd444 | 2643 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2644 | } |
2645 | ||
2646 | int cpufreq_enable_boost_support(void) | |
2647 | { | |
2648 | if (!cpufreq_driver) | |
2649 | return -EINVAL; | |
2650 | ||
2651 | if (cpufreq_boost_supported()) | |
2652 | return 0; | |
2653 | ||
7a6c79f2 | 2654 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2655 | |
2656 | /* This will get removed on driver unregister */ | |
2657 | return create_boost_sysfs_file(); | |
2658 | } | |
2659 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2660 | ||
6f19efc0 LM |
2661 | int cpufreq_boost_enabled(void) |
2662 | { | |
2663 | return cpufreq_driver->boost_enabled; | |
2664 | } | |
2665 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2666 | ||
1da177e4 LT |
2667 | /********************************************************************* |
2668 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2669 | *********************************************************************/ | |
27622b06 | 2670 | static enum cpuhp_state hp_online; |
1da177e4 | 2671 | |
c4a3fa26 CY |
2672 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2673 | { | |
2674 | cpufreq_online(cpu); | |
2675 | ||
2676 | return 0; | |
2677 | } | |
2678 | ||
2679 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2680 | { | |
2681 | cpufreq_offline(cpu); | |
2682 | ||
2683 | return 0; | |
2684 | } | |
2685 | ||
1da177e4 LT |
2686 | /** |
2687 | * cpufreq_register_driver - register a CPU Frequency driver | |
2688 | * @driver_data: A struct cpufreq_driver containing the values# | |
2689 | * submitted by the CPU Frequency driver. | |
2690 | * | |
bb176f7d | 2691 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2692 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2693 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2694 | * |
2695 | */ | |
221dee28 | 2696 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2697 | { |
2698 | unsigned long flags; | |
2699 | int ret; | |
2700 | ||
a7b422cd KRW |
2701 | if (cpufreq_disabled()) |
2702 | return -ENODEV; | |
2703 | ||
46770be0 VK |
2704 | /* |
2705 | * The cpufreq core depends heavily on the availability of device | |
2706 | * structure, make sure they are available before proceeding further. | |
2707 | */ | |
2708 | if (!get_cpu_device(0)) | |
2709 | return -EPROBE_DEFER; | |
2710 | ||
1da177e4 | 2711 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2712 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2713 | driver_data->target) || |
2714 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2715 | driver_data->target)) || |
a9a22b57 | 2716 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2717 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2718 | return -EINVAL; |
2719 | ||
2d06d8c4 | 2720 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2721 | |
fdd320da | 2722 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2723 | cpus_read_lock(); |
fdd320da | 2724 | |
0d1857a1 | 2725 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2726 | if (cpufreq_driver) { |
0d1857a1 | 2727 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2728 | ret = -EEXIST; |
2729 | goto out; | |
1da177e4 | 2730 | } |
1c3d85dd | 2731 | cpufreq_driver = driver_data; |
0d1857a1 | 2732 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2733 | |
874f6353 IV |
2734 | /* |
2735 | * Mark support for the scheduler's frequency invariance engine for | |
2736 | * drivers that implement target(), target_index() or fast_switch(). | |
2737 | */ | |
2738 | if (!cpufreq_driver->setpolicy) { | |
2739 | static_branch_enable_cpuslocked(&cpufreq_freq_invariance); | |
2740 | pr_debug("supports frequency invariance"); | |
2741 | } | |
2742 | ||
bc68b7df VK |
2743 | if (driver_data->setpolicy) |
2744 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2745 | ||
7a6c79f2 RW |
2746 | if (cpufreq_boost_supported()) { |
2747 | ret = create_boost_sysfs_file(); | |
2748 | if (ret) | |
2749 | goto err_null_driver; | |
2750 | } | |
6f19efc0 | 2751 | |
8a25a2fd | 2752 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2753 | if (ret) |
6f19efc0 | 2754 | goto err_boost_unreg; |
1da177e4 | 2755 | |
ce1bcfe9 VK |
2756 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2757 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2758 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2759 | ret = -ENODEV; |
ce1bcfe9 VK |
2760 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2761 | driver_data->name); | |
2762 | goto err_if_unreg; | |
1da177e4 LT |
2763 | } |
2764 | ||
a92551e4 SAS |
2765 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2766 | "cpufreq:online", | |
2767 | cpuhp_cpufreq_online, | |
2768 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2769 | if (ret < 0) |
2770 | goto err_if_unreg; | |
2771 | hp_online = ret; | |
5372e054 | 2772 | ret = 0; |
27622b06 | 2773 | |
2d06d8c4 | 2774 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2775 | goto out; |
fdd320da | 2776 | |
8a25a2fd KS |
2777 | err_if_unreg: |
2778 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2779 | err_boost_unreg: |
44139ed4 | 2780 | remove_boost_sysfs_file(); |
8f5bc2ab | 2781 | err_null_driver: |
0d1857a1 | 2782 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2783 | cpufreq_driver = NULL; |
0d1857a1 | 2784 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2785 | out: |
a92551e4 | 2786 | cpus_read_unlock(); |
3834abb4 | 2787 | return ret; |
1da177e4 LT |
2788 | } |
2789 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2790 | ||
a9909c21 | 2791 | /* |
1da177e4 LT |
2792 | * cpufreq_unregister_driver - unregister the current CPUFreq driver |
2793 | * | |
bb176f7d | 2794 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2795 | * the right to do so, i.e. if you have succeeded in initialising before! |
2796 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2797 | * currently not initialised. | |
2798 | */ | |
221dee28 | 2799 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2800 | { |
2801 | unsigned long flags; | |
2802 | ||
1c3d85dd | 2803 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2804 | return -EINVAL; |
1da177e4 | 2805 | |
2d06d8c4 | 2806 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2807 | |
454d3a25 | 2808 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2809 | cpus_read_lock(); |
8a25a2fd | 2810 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2811 | remove_boost_sysfs_file(); |
874f6353 | 2812 | static_branch_disable_cpuslocked(&cpufreq_freq_invariance); |
a92551e4 | 2813 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2814 | |
0d1857a1 | 2815 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2816 | |
1c3d85dd | 2817 | cpufreq_driver = NULL; |
6eed9404 | 2818 | |
0d1857a1 | 2819 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2820 | cpus_read_unlock(); |
1da177e4 LT |
2821 | |
2822 | return 0; | |
2823 | } | |
2824 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2825 | |
2826 | static int __init cpufreq_core_init(void) | |
2827 | { | |
8412b456 QP |
2828 | struct cpufreq_governor *gov = cpufreq_default_governor(); |
2829 | ||
a7b422cd KRW |
2830 | if (cpufreq_disabled()) |
2831 | return -ENODEV; | |
2832 | ||
8eec1020 | 2833 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2834 | BUG_ON(!cpufreq_global_kobject); |
2835 | ||
8412b456 QP |
2836 | if (!strlen(default_governor)) |
2837 | strncpy(default_governor, gov->name, CPUFREQ_NAME_LEN); | |
2838 | ||
5a01f2e8 VP |
2839 | return 0; |
2840 | } | |
d82f2692 | 2841 | module_param(off, int, 0444); |
8412b456 | 2842 | module_param_string(default_governor, default_governor, CPUFREQ_NAME_LEN, 0444); |
5a01f2e8 | 2843 | core_initcall(cpufreq_core_init); |