Commit | Line | Data |
---|---|---|
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 | ||
1da177e4 | 53 | /** |
cd878479 | 54 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
55 | * level driver of CPUFreq support, and its spinlock. This lock |
56 | * also protects the cpufreq_cpu_data array. | |
57 | */ | |
1c3d85dd | 58 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 59 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 60 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 61 | |
2f0aea93 VK |
62 | /* Flag to suspend/resume CPUFreq governors */ |
63 | static bool cpufreq_suspended; | |
1da177e4 | 64 | |
9c0ebcf7 VK |
65 | static inline bool has_target(void) |
66 | { | |
67 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
68 | } | |
69 | ||
1da177e4 | 70 | /* internal prototypes */ |
d92d50a4 | 71 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
72 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
73 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
0a300767 | 74 | static int cpufreq_start_governor(struct cpufreq_policy *policy); |
a92604b4 RW |
75 | static void cpufreq_stop_governor(struct cpufreq_policy *policy); |
76 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); | |
45482c70 | 77 | |
1da177e4 | 78 | /** |
32ee8c3e DJ |
79 | * Two notifier lists: the "policy" list is involved in the |
80 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
81 | * "transition" list for kernel code that needs to handle |
82 | * changes to devices when the CPU clock speed changes. | |
83 | * The mutex locks both lists. | |
84 | */ | |
e041c683 | 85 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 86 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 87 | |
a7b422cd | 88 | static int off __read_mostly; |
da584455 | 89 | static int cpufreq_disabled(void) |
a7b422cd KRW |
90 | { |
91 | return off; | |
92 | } | |
93 | void disable_cpufreq(void) | |
94 | { | |
95 | off = 1; | |
96 | } | |
29464f28 | 97 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 98 | |
4d5dcc42 VK |
99 | bool have_governor_per_policy(void) |
100 | { | |
0b981e70 | 101 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 102 | } |
3f869d6d | 103 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 104 | |
944e9a03 VK |
105 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
106 | { | |
107 | if (have_governor_per_policy()) | |
108 | return &policy->kobj; | |
109 | else | |
110 | return cpufreq_global_kobject; | |
111 | } | |
112 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
113 | ||
72a4ce34 VK |
114 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
115 | { | |
5720821b | 116 | struct kernel_cpustat kcpustat; |
72a4ce34 | 117 | u64 cur_wall_time; |
5720821b | 118 | u64 idle_time; |
72a4ce34 VK |
119 | u64 busy_time; |
120 | ||
7fb1327e | 121 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 | 122 | |
5720821b FW |
123 | kcpustat_cpu_fetch(&kcpustat, cpu); |
124 | ||
125 | busy_time = kcpustat.cpustat[CPUTIME_USER]; | |
126 | busy_time += kcpustat.cpustat[CPUTIME_SYSTEM]; | |
127 | busy_time += kcpustat.cpustat[CPUTIME_IRQ]; | |
128 | busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ]; | |
129 | busy_time += kcpustat.cpustat[CPUTIME_STEAL]; | |
130 | busy_time += kcpustat.cpustat[CPUTIME_NICE]; | |
72a4ce34 VK |
131 | |
132 | idle_time = cur_wall_time - busy_time; | |
133 | if (wall) | |
7fb1327e | 134 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 135 | |
7fb1327e | 136 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
137 | } |
138 | ||
139 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
140 | { | |
141 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
142 | ||
143 | if (idle_time == -1ULL) | |
144 | return get_cpu_idle_time_jiffy(cpu, wall); | |
145 | else if (!io_busy) | |
146 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
147 | ||
148 | return idle_time; | |
149 | } | |
150 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
151 | ||
e7d5459d DE |
152 | __weak void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, |
153 | unsigned long max_freq) | |
154 | { | |
155 | } | |
156 | EXPORT_SYMBOL_GPL(arch_set_freq_scale); | |
157 | ||
70e9e778 VK |
158 | /* |
159 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
160 | * drivers of SMP systems. It will do following: | |
161 | * - validate & show freq table passed | |
162 | * - set policies transition latency | |
163 | * - policy->cpus with all possible CPUs | |
164 | */ | |
c4dcc8a1 | 165 | void cpufreq_generic_init(struct cpufreq_policy *policy, |
70e9e778 VK |
166 | struct cpufreq_frequency_table *table, |
167 | unsigned int transition_latency) | |
168 | { | |
92c99d15 | 169 | policy->freq_table = table; |
70e9e778 VK |
170 | policy->cpuinfo.transition_latency = transition_latency; |
171 | ||
172 | /* | |
58405af6 | 173 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
174 | * share the clock and voltage and clock. |
175 | */ | |
176 | cpumask_setall(policy->cpus); | |
70e9e778 VK |
177 | } |
178 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
179 | ||
1f0bd44e | 180 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
181 | { |
182 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
183 | ||
988bed09 VK |
184 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
185 | } | |
1f0bd44e | 186 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
187 | |
188 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
189 | { | |
190 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
191 | ||
652ed95d | 192 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
193 | pr_err("%s: No %s associated to cpu: %d\n", |
194 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
195 | return 0; |
196 | } | |
197 | ||
198 | return clk_get_rate(policy->clk) / 1000; | |
199 | } | |
200 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
201 | ||
50e9c852 | 202 | /** |
5d094fea RW |
203 | * cpufreq_cpu_get - Return policy for a CPU and mark it as busy. |
204 | * @cpu: CPU to find the policy for. | |
50e9c852 | 205 | * |
5d094fea RW |
206 | * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment |
207 | * the kobject reference counter of that policy. Return a valid policy on | |
208 | * success or NULL on failure. | |
50e9c852 | 209 | * |
5d094fea RW |
210 | * The policy returned by this function has to be released with the help of |
211 | * cpufreq_cpu_put() to balance its kobject reference counter properly. | |
50e9c852 | 212 | */ |
6eed9404 | 213 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 214 | { |
6eed9404 | 215 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
216 | unsigned long flags; |
217 | ||
1b947c90 | 218 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
219 | return NULL; |
220 | ||
1da177e4 | 221 | /* get the cpufreq driver */ |
1c3d85dd | 222 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 223 | |
6eed9404 VK |
224 | if (cpufreq_driver) { |
225 | /* get the CPU */ | |
988bed09 | 226 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
227 | if (policy) |
228 | kobject_get(&policy->kobj); | |
229 | } | |
1da177e4 | 230 | |
6eed9404 | 231 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 232 | |
3a3e9e06 | 233 | return policy; |
a9144436 | 234 | } |
1da177e4 LT |
235 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
236 | ||
50e9c852 | 237 | /** |
5d094fea RW |
238 | * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy. |
239 | * @policy: cpufreq policy returned by cpufreq_cpu_get(). | |
50e9c852 | 240 | */ |
3a3e9e06 | 241 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 242 | { |
6eed9404 | 243 | kobject_put(&policy->kobj); |
1da177e4 LT |
244 | } |
245 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
246 | ||
540a3758 RW |
247 | /** |
248 | * cpufreq_cpu_release - Unlock a policy and decrement its usage counter. | |
249 | * @policy: cpufreq policy returned by cpufreq_cpu_acquire(). | |
250 | */ | |
9083e498 | 251 | void cpufreq_cpu_release(struct cpufreq_policy *policy) |
540a3758 RW |
252 | { |
253 | if (WARN_ON(!policy)) | |
254 | return; | |
255 | ||
256 | lockdep_assert_held(&policy->rwsem); | |
257 | ||
258 | up_write(&policy->rwsem); | |
259 | ||
260 | cpufreq_cpu_put(policy); | |
261 | } | |
262 | ||
263 | /** | |
264 | * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it. | |
265 | * @cpu: CPU to find the policy for. | |
266 | * | |
267 | * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and | |
268 | * if the policy returned by it is not NULL, acquire its rwsem for writing. | |
269 | * Return the policy if it is active or release it and return NULL otherwise. | |
270 | * | |
271 | * The policy returned by this function has to be released with the help of | |
272 | * cpufreq_cpu_release() in order to release its rwsem and balance its usage | |
273 | * counter properly. | |
274 | */ | |
9083e498 | 275 | struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu) |
540a3758 RW |
276 | { |
277 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
278 | ||
279 | if (!policy) | |
280 | return NULL; | |
281 | ||
282 | down_write(&policy->rwsem); | |
283 | ||
284 | if (policy_is_inactive(policy)) { | |
285 | cpufreq_cpu_release(policy); | |
286 | return NULL; | |
287 | } | |
288 | ||
289 | return policy; | |
290 | } | |
291 | ||
1da177e4 LT |
292 | /********************************************************************* |
293 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
294 | *********************************************************************/ | |
295 | ||
296 | /** | |
297 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
298 | * | |
299 | * This function alters the system "loops_per_jiffy" for the clock | |
300 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 301 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
302 | * per-CPU loops_per_jiffy value wherever possible. |
303 | */ | |
858119e1 | 304 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 305 | { |
39c132ee VK |
306 | #ifndef CONFIG_SMP |
307 | static unsigned long l_p_j_ref; | |
308 | static unsigned int l_p_j_ref_freq; | |
309 | ||
1da177e4 LT |
310 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
311 | return; | |
312 | ||
313 | if (!l_p_j_ref_freq) { | |
314 | l_p_j_ref = loops_per_jiffy; | |
315 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
316 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
317 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 318 | } |
0b443ead | 319 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
320 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
321 | ci->new); | |
e837f9b5 JP |
322 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
323 | loops_per_jiffy, ci->new); | |
1da177e4 | 324 | } |
1da177e4 | 325 | #endif |
39c132ee | 326 | } |
1da177e4 | 327 | |
20b5324d VK |
328 | /** |
329 | * cpufreq_notify_transition - Notify frequency transition and adjust_jiffies. | |
330 | * @policy: cpufreq policy to enable fast frequency switching for. | |
331 | * @freqs: contain details of the frequency update. | |
332 | * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. | |
333 | * | |
334 | * This function calls the transition notifiers and the "adjust_jiffies" | |
335 | * function. It is called twice on all CPU frequency changes that have | |
336 | * external effects. | |
337 | */ | |
338 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
339 | struct cpufreq_freqs *freqs, | |
340 | unsigned int state) | |
1da177e4 | 341 | { |
df24014a VK |
342 | int cpu; |
343 | ||
1da177e4 LT |
344 | BUG_ON(irqs_disabled()); |
345 | ||
d5aaffa9 DB |
346 | if (cpufreq_disabled()) |
347 | return; | |
348 | ||
df24014a | 349 | freqs->policy = policy; |
1c3d85dd | 350 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 351 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 352 | state, freqs->new); |
1da177e4 | 353 | |
1da177e4 LT |
354 | switch (state) { |
355 | case CPUFREQ_PRECHANGE: | |
20b5324d VK |
356 | /* |
357 | * Detect if the driver reported a value as "old frequency" | |
e4472cb3 DJ |
358 | * which is not equal to what the cpufreq core thinks is |
359 | * "old frequency". | |
1da177e4 | 360 | */ |
98015228 VK |
361 | if (policy->cur && policy->cur != freqs->old) { |
362 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", | |
363 | freqs->old, policy->cur); | |
364 | freqs->old = policy->cur; | |
1da177e4 | 365 | } |
20b5324d | 366 | |
df24014a VK |
367 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
368 | CPUFREQ_PRECHANGE, freqs); | |
20b5324d | 369 | |
1da177e4 LT |
370 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
371 | break; | |
e4472cb3 | 372 | |
1da177e4 LT |
373 | case CPUFREQ_POSTCHANGE: |
374 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
20b5324d VK |
375 | pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, |
376 | cpumask_pr_args(policy->cpus)); | |
377 | ||
df24014a VK |
378 | for_each_cpu(cpu, policy->cpus) |
379 | trace_cpu_frequency(freqs->new, cpu); | |
380 | ||
381 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, | |
382 | CPUFREQ_POSTCHANGE, freqs); | |
20b5324d | 383 | |
1aefc75b | 384 | cpufreq_stats_record_transition(policy, freqs->new); |
20b5324d | 385 | policy->cur = freqs->new; |
1da177e4 | 386 | } |
1da177e4 | 387 | } |
bb176f7d | 388 | |
f7ba3b41 | 389 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 390 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
391 | struct cpufreq_freqs *freqs, int transition_failed) |
392 | { | |
393 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
394 | if (!transition_failed) | |
395 | return; | |
396 | ||
397 | swap(freqs->old, freqs->new); | |
398 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
399 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
400 | } | |
f7ba3b41 | 401 | |
12478cf0 SB |
402 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
403 | struct cpufreq_freqs *freqs) | |
404 | { | |
ca654dc3 SB |
405 | |
406 | /* | |
407 | * Catch double invocations of _begin() which lead to self-deadlock. | |
408 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
409 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
410 | * double invocations are very low. Moreover, there are scenarios | |
411 | * where these checks can emit false-positive warnings in these | |
412 | * drivers; so we avoid that by skipping them altogether. | |
413 | */ | |
414 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
415 | && current == policy->transition_task); | |
416 | ||
12478cf0 SB |
417 | wait: |
418 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
419 | ||
420 | spin_lock(&policy->transition_lock); | |
421 | ||
422 | if (unlikely(policy->transition_ongoing)) { | |
423 | spin_unlock(&policy->transition_lock); | |
424 | goto wait; | |
425 | } | |
426 | ||
427 | policy->transition_ongoing = true; | |
ca654dc3 | 428 | policy->transition_task = current; |
12478cf0 SB |
429 | |
430 | spin_unlock(&policy->transition_lock); | |
431 | ||
432 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
433 | } | |
434 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
435 | ||
436 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
437 | struct cpufreq_freqs *freqs, int transition_failed) | |
438 | { | |
0e7ea2f3 | 439 | if (WARN_ON(!policy->transition_ongoing)) |
12478cf0 SB |
440 | return; |
441 | ||
442 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
443 | ||
444 | policy->transition_ongoing = false; | |
ca654dc3 | 445 | policy->transition_task = NULL; |
12478cf0 SB |
446 | |
447 | wake_up(&policy->transition_wait); | |
448 | } | |
449 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
450 | ||
b7898fda RW |
451 | /* |
452 | * Fast frequency switching status count. Positive means "enabled", negative | |
453 | * means "disabled" and 0 means "not decided yet". | |
454 | */ | |
455 | static int cpufreq_fast_switch_count; | |
456 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
457 | ||
458 | static void cpufreq_list_transition_notifiers(void) | |
459 | { | |
460 | struct notifier_block *nb; | |
461 | ||
462 | pr_info("Registered transition notifiers:\n"); | |
463 | ||
464 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
465 | ||
466 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
d75f773c | 467 | pr_info("%pS\n", nb->notifier_call); |
b7898fda RW |
468 | |
469 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
470 | } | |
471 | ||
472 | /** | |
473 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
474 | * @policy: cpufreq policy to enable fast frequency switching for. | |
475 | * | |
476 | * Try to enable fast frequency switching for @policy. | |
477 | * | |
478 | * The attempt will fail if there is at least one transition notifier registered | |
479 | * at this point, as fast frequency switching is quite fundamentally at odds | |
480 | * with transition notifiers. Thus if successful, it will make registration of | |
481 | * transition notifiers fail going forward. | |
482 | */ | |
483 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
484 | { | |
485 | lockdep_assert_held(&policy->rwsem); | |
486 | ||
487 | if (!policy->fast_switch_possible) | |
488 | return; | |
489 | ||
490 | mutex_lock(&cpufreq_fast_switch_lock); | |
491 | if (cpufreq_fast_switch_count >= 0) { | |
492 | cpufreq_fast_switch_count++; | |
493 | policy->fast_switch_enabled = true; | |
494 | } else { | |
495 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
496 | policy->cpu); | |
497 | cpufreq_list_transition_notifiers(); | |
498 | } | |
499 | mutex_unlock(&cpufreq_fast_switch_lock); | |
500 | } | |
501 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
502 | ||
6c9d9c81 RW |
503 | /** |
504 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
505 | * @policy: cpufreq policy to disable fast frequency switching for. | |
506 | */ | |
507 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
508 | { |
509 | mutex_lock(&cpufreq_fast_switch_lock); | |
510 | if (policy->fast_switch_enabled) { | |
511 | policy->fast_switch_enabled = false; | |
512 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
513 | cpufreq_fast_switch_count--; | |
514 | } | |
515 | mutex_unlock(&cpufreq_fast_switch_lock); | |
516 | } | |
6c9d9c81 | 517 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 518 | |
e3c06236 SM |
519 | /** |
520 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
521 | * one. | |
522 | * @target_freq: target frequency to resolve. | |
523 | * | |
524 | * The target to driver frequency mapping is cached in the policy. | |
525 | * | |
526 | * Return: Lowest driver-supported frequency greater than or equal to the | |
527 | * given target_freq, subject to policy (min/max) and driver limitations. | |
528 | */ | |
529 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
530 | unsigned int target_freq) | |
531 | { | |
532 | target_freq = clamp_val(target_freq, policy->min, policy->max); | |
533 | policy->cached_target_freq = target_freq; | |
abe8bd02 VK |
534 | |
535 | if (cpufreq_driver->target_index) { | |
536 | int idx; | |
537 | ||
538 | idx = cpufreq_frequency_table_target(policy, target_freq, | |
539 | CPUFREQ_RELATION_L); | |
540 | policy->cached_resolved_idx = idx; | |
541 | return policy->freq_table[idx].frequency; | |
542 | } | |
543 | ||
e3c06236 SM |
544 | if (cpufreq_driver->resolve_freq) |
545 | return cpufreq_driver->resolve_freq(policy, target_freq); | |
abe8bd02 VK |
546 | |
547 | return target_freq; | |
e3c06236 | 548 | } |
ae2c1ca6 | 549 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 550 | |
aa7519af VK |
551 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
552 | { | |
553 | unsigned int latency; | |
554 | ||
555 | if (policy->transition_delay_us) | |
556 | return policy->transition_delay_us; | |
557 | ||
558 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
559 | if (latency) { |
560 | /* | |
561 | * For platforms that can change the frequency very fast (< 10 | |
562 | * us), the above formula gives a decent transition delay. But | |
563 | * for platforms where transition_latency is in milliseconds, it | |
564 | * ends up giving unrealistic values. | |
565 | * | |
566 | * Cap the default transition delay to 10 ms, which seems to be | |
567 | * a reasonable amount of time after which we should reevaluate | |
568 | * the frequency. | |
569 | */ | |
570 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
571 | } | |
aa7519af VK |
572 | |
573 | return LATENCY_MULTIPLIER; | |
574 | } | |
575 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
576 | ||
1da177e4 LT |
577 | /********************************************************************* |
578 | * SYSFS INTERFACE * | |
579 | *********************************************************************/ | |
8a5c74a1 | 580 | static ssize_t show_boost(struct kobject *kobj, |
625c85a6 | 581 | struct kobj_attribute *attr, char *buf) |
6f19efc0 LM |
582 | { |
583 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
584 | } | |
585 | ||
625c85a6 VK |
586 | static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr, |
587 | const char *buf, size_t count) | |
6f19efc0 LM |
588 | { |
589 | int ret, enable; | |
590 | ||
591 | ret = sscanf(buf, "%d", &enable); | |
592 | if (ret != 1 || enable < 0 || enable > 1) | |
593 | return -EINVAL; | |
594 | ||
595 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
596 | pr_err("%s: Cannot %s BOOST!\n", |
597 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
598 | return -EINVAL; |
599 | } | |
600 | ||
e837f9b5 JP |
601 | pr_debug("%s: cpufreq BOOST %s\n", |
602 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
603 | |
604 | return count; | |
605 | } | |
606 | define_one_global_rw(boost); | |
1da177e4 | 607 | |
42f91fa1 | 608 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
609 | { |
610 | struct cpufreq_governor *t; | |
611 | ||
f7b27061 | 612 | for_each_governor(t) |
7c4f4539 | 613 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
614 | return t; |
615 | ||
616 | return NULL; | |
617 | } | |
618 | ||
ab05d97a YH |
619 | static int cpufreq_parse_policy(char *str_governor, |
620 | struct cpufreq_policy *policy) | |
621 | { | |
622 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { | |
623 | policy->policy = CPUFREQ_POLICY_PERFORMANCE; | |
624 | return 0; | |
625 | } | |
626 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) { | |
627 | policy->policy = CPUFREQ_POLICY_POWERSAVE; | |
628 | return 0; | |
629 | } | |
630 | return -EINVAL; | |
631 | } | |
632 | ||
1da177e4 | 633 | /** |
5ddc6d4e | 634 | * cpufreq_parse_governor - parse a governor string only for has_target() |
1da177e4 | 635 | */ |
ae0ff89f RW |
636 | static int cpufreq_parse_governor(char *str_governor, |
637 | struct cpufreq_policy *policy) | |
1da177e4 | 638 | { |
ab05d97a | 639 | struct cpufreq_governor *t; |
045149e6 | 640 | |
ab05d97a | 641 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 642 | |
ab05d97a YH |
643 | t = find_governor(str_governor); |
644 | if (!t) { | |
645 | int ret; | |
3bcb09a3 | 646 | |
ab05d97a | 647 | mutex_unlock(&cpufreq_governor_mutex); |
045149e6 | 648 | |
ab05d97a YH |
649 | ret = request_module("cpufreq_%s", str_governor); |
650 | if (ret) | |
651 | return -EINVAL; | |
045149e6 | 652 | |
ab05d97a | 653 | mutex_lock(&cpufreq_governor_mutex); |
ea714970 | 654 | |
ab05d97a YH |
655 | t = find_governor(str_governor); |
656 | } | |
657 | if (t && !try_module_get(t->owner)) | |
658 | t = NULL; | |
ea714970 | 659 | |
ab05d97a | 660 | mutex_unlock(&cpufreq_governor_mutex); |
045149e6 | 661 | |
ab05d97a YH |
662 | if (t) { |
663 | policy->governor = t; | |
664 | return 0; | |
1da177e4 | 665 | } |
045149e6 RW |
666 | |
667 | return -EINVAL; | |
1da177e4 | 668 | } |
1da177e4 | 669 | |
1da177e4 | 670 | /** |
e08f5f5b GS |
671 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
672 | * print out cpufreq information | |
1da177e4 LT |
673 | * |
674 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
675 | * "unsigned int". | |
676 | */ | |
677 | ||
32ee8c3e DJ |
678 | #define show_one(file_name, object) \ |
679 | static ssize_t show_##file_name \ | |
905d77cd | 680 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 681 | { \ |
29464f28 | 682 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
683 | } |
684 | ||
685 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
686 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 687 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
688 | show_one(scaling_min_freq, min); |
689 | show_one(scaling_max_freq, max); | |
c034b02e | 690 | |
f8475cef LB |
691 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
692 | { | |
693 | return 0; | |
694 | } | |
695 | ||
09347b29 | 696 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
697 | { |
698 | ssize_t ret; | |
f8475cef | 699 | unsigned int freq; |
c034b02e | 700 | |
f8475cef LB |
701 | freq = arch_freq_get_on_cpu(policy->cpu); |
702 | if (freq) | |
703 | ret = sprintf(buf, "%u\n", freq); | |
704 | else if (cpufreq_driver && cpufreq_driver->setpolicy && | |
705 | cpufreq_driver->get) | |
c034b02e DB |
706 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
707 | else | |
708 | ret = sprintf(buf, "%u\n", policy->cur); | |
709 | return ret; | |
710 | } | |
1da177e4 LT |
711 | |
712 | /** | |
713 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
714 | */ | |
715 | #define store_one(file_name, object) \ | |
716 | static ssize_t store_##file_name \ | |
905d77cd | 717 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 718 | { \ |
18c49926 VK |
719 | unsigned long val; \ |
720 | int ret; \ | |
1da177e4 | 721 | \ |
18c49926 | 722 | ret = sscanf(buf, "%lu", &val); \ |
1da177e4 LT |
723 | if (ret != 1) \ |
724 | return -EINVAL; \ | |
725 | \ | |
3000ce3c | 726 | ret = freq_qos_update_request(policy->object##_freq_req, val);\ |
18c49926 | 727 | return ret >= 0 ? count : ret; \ |
1da177e4 LT |
728 | } |
729 | ||
29464f28 DJ |
730 | store_one(scaling_min_freq, min); |
731 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
732 | |
733 | /** | |
734 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
735 | */ | |
905d77cd DJ |
736 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
737 | char *buf) | |
1da177e4 | 738 | { |
d92d50a4 | 739 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
740 | |
741 | if (cur_freq) | |
742 | return sprintf(buf, "%u\n", cur_freq); | |
743 | ||
744 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
745 | } |
746 | ||
1da177e4 LT |
747 | /** |
748 | * show_scaling_governor - show the current policy for the specified CPU | |
749 | */ | |
905d77cd | 750 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 751 | { |
29464f28 | 752 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
753 | return sprintf(buf, "powersave\n"); |
754 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
755 | return sprintf(buf, "performance\n"); | |
756 | else if (policy->governor) | |
4b972f0b | 757 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 758 | policy->governor->name); |
1da177e4 LT |
759 | return -EINVAL; |
760 | } | |
761 | ||
1da177e4 LT |
762 | /** |
763 | * store_scaling_governor - store policy for the specified CPU | |
764 | */ | |
905d77cd DJ |
765 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
766 | const char *buf, size_t count) | |
1da177e4 | 767 | { |
5136fa56 | 768 | int ret; |
1da177e4 LT |
769 | char str_governor[16]; |
770 | struct cpufreq_policy new_policy; | |
771 | ||
8fa5b631 | 772 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 773 | |
29464f28 | 774 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
775 | if (ret != 1) |
776 | return -EINVAL; | |
777 | ||
ab05d97a YH |
778 | if (cpufreq_driver->setpolicy) { |
779 | if (cpufreq_parse_policy(str_governor, &new_policy)) | |
780 | return -EINVAL; | |
781 | } else { | |
782 | if (cpufreq_parse_governor(str_governor, &new_policy)) | |
783 | return -EINVAL; | |
784 | } | |
1da177e4 | 785 | |
037ce839 | 786 | ret = cpufreq_set_policy(policy, &new_policy); |
a8b149d3 RW |
787 | |
788 | if (new_policy.governor) | |
789 | module_put(new_policy.governor->owner); | |
790 | ||
88dc4384 | 791 | return ret ? ret : count; |
1da177e4 LT |
792 | } |
793 | ||
794 | /** | |
795 | * show_scaling_driver - show the cpufreq driver currently loaded | |
796 | */ | |
905d77cd | 797 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 798 | { |
1c3d85dd | 799 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
800 | } |
801 | ||
802 | /** | |
803 | * show_scaling_available_governors - show the available CPUfreq governors | |
804 | */ | |
905d77cd DJ |
805 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
806 | char *buf) | |
1da177e4 LT |
807 | { |
808 | ssize_t i = 0; | |
809 | struct cpufreq_governor *t; | |
810 | ||
9c0ebcf7 | 811 | if (!has_target()) { |
1da177e4 LT |
812 | i += sprintf(buf, "performance powersave"); |
813 | goto out; | |
814 | } | |
815 | ||
f7b27061 | 816 | for_each_governor(t) { |
29464f28 DJ |
817 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
818 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 819 | goto out; |
4b972f0b | 820 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 821 | } |
7d5e350f | 822 | out: |
1da177e4 LT |
823 | i += sprintf(&buf[i], "\n"); |
824 | return i; | |
825 | } | |
e8628dd0 | 826 | |
f4fd3797 | 827 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
828 | { |
829 | ssize_t i = 0; | |
830 | unsigned int cpu; | |
831 | ||
835481d9 | 832 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
833 | if (i) |
834 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
835 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
836 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 837 | break; |
1da177e4 LT |
838 | } |
839 | i += sprintf(&buf[i], "\n"); | |
840 | return i; | |
841 | } | |
f4fd3797 | 842 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 843 | |
e8628dd0 DW |
844 | /** |
845 | * show_related_cpus - show the CPUs affected by each transition even if | |
846 | * hw coordination is in use | |
847 | */ | |
848 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
849 | { | |
f4fd3797 | 850 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
851 | } |
852 | ||
853 | /** | |
854 | * show_affected_cpus - show the CPUs affected by each transition | |
855 | */ | |
856 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
857 | { | |
f4fd3797 | 858 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
859 | } |
860 | ||
9e76988e | 861 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 862 | const char *buf, size_t count) |
9e76988e VP |
863 | { |
864 | unsigned int freq = 0; | |
865 | unsigned int ret; | |
866 | ||
879000f9 | 867 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
868 | return -EINVAL; |
869 | ||
870 | ret = sscanf(buf, "%u", &freq); | |
871 | if (ret != 1) | |
872 | return -EINVAL; | |
873 | ||
874 | policy->governor->store_setspeed(policy, freq); | |
875 | ||
876 | return count; | |
877 | } | |
878 | ||
879 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
880 | { | |
879000f9 | 881 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
882 | return sprintf(buf, "<unsupported>\n"); |
883 | ||
884 | return policy->governor->show_setspeed(policy, buf); | |
885 | } | |
1da177e4 | 886 | |
e2f74f35 | 887 | /** |
8bf1ac72 | 888 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
889 | */ |
890 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
891 | { | |
892 | unsigned int limit; | |
893 | int ret; | |
b23aa311 YH |
894 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
895 | if (!ret) | |
896 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
897 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
898 | } | |
899 | ||
6dad2a29 BP |
900 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
901 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
902 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
903 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
904 | cpufreq_freq_attr_ro(scaling_available_governors); | |
905 | cpufreq_freq_attr_ro(scaling_driver); | |
906 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
907 | cpufreq_freq_attr_ro(bios_limit); | |
908 | cpufreq_freq_attr_ro(related_cpus); | |
909 | cpufreq_freq_attr_ro(affected_cpus); | |
910 | cpufreq_freq_attr_rw(scaling_min_freq); | |
911 | cpufreq_freq_attr_rw(scaling_max_freq); | |
912 | cpufreq_freq_attr_rw(scaling_governor); | |
913 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 914 | |
905d77cd | 915 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
916 | &cpuinfo_min_freq.attr, |
917 | &cpuinfo_max_freq.attr, | |
ed129784 | 918 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
919 | &scaling_min_freq.attr, |
920 | &scaling_max_freq.attr, | |
921 | &affected_cpus.attr, | |
e8628dd0 | 922 | &related_cpus.attr, |
1da177e4 LT |
923 | &scaling_governor.attr, |
924 | &scaling_driver.attr, | |
925 | &scaling_available_governors.attr, | |
9e76988e | 926 | &scaling_setspeed.attr, |
1da177e4 LT |
927 | NULL |
928 | }; | |
929 | ||
29464f28 DJ |
930 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
931 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 932 | |
29464f28 | 933 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 934 | { |
905d77cd DJ |
935 | struct cpufreq_policy *policy = to_policy(kobj); |
936 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 937 | ssize_t ret; |
6eed9404 | 938 | |
e6e8df07 KS |
939 | if (!fattr->show) |
940 | return -EIO; | |
941 | ||
ad7722da | 942 | down_read(&policy->rwsem); |
6541aef0 | 943 | ret = fattr->show(policy, buf); |
ad7722da | 944 | up_read(&policy->rwsem); |
1b750e3b | 945 | |
1da177e4 LT |
946 | return ret; |
947 | } | |
948 | ||
905d77cd DJ |
949 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
950 | const char *buf, size_t count) | |
1da177e4 | 951 | { |
905d77cd DJ |
952 | struct cpufreq_policy *policy = to_policy(kobj); |
953 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 954 | ssize_t ret = -EINVAL; |
6eed9404 | 955 | |
e6e8df07 KS |
956 | if (!fattr->store) |
957 | return -EIO; | |
958 | ||
9b3d9bb3 WL |
959 | /* |
960 | * cpus_read_trylock() is used here to work around a circular lock | |
961 | * dependency problem with respect to the cpufreq_register_driver(). | |
962 | */ | |
963 | if (!cpus_read_trylock()) | |
964 | return -EBUSY; | |
4f750c93 | 965 | |
6541aef0 RW |
966 | if (cpu_online(policy->cpu)) { |
967 | down_write(&policy->rwsem); | |
e08f5f5b | 968 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
969 | up_write(&policy->rwsem); |
970 | } | |
e08f5f5b | 971 | |
a92551e4 | 972 | cpus_read_unlock(); |
4f750c93 | 973 | |
1da177e4 LT |
974 | return ret; |
975 | } | |
976 | ||
905d77cd | 977 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 978 | { |
905d77cd | 979 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 980 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
981 | complete(&policy->kobj_unregister); |
982 | } | |
983 | ||
52cf25d0 | 984 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
985 | .show = show, |
986 | .store = store, | |
987 | }; | |
988 | ||
989 | static struct kobj_type ktype_cpufreq = { | |
990 | .sysfs_ops = &sysfs_ops, | |
991 | .default_attrs = default_attrs, | |
992 | .release = cpufreq_sysfs_release, | |
993 | }; | |
994 | ||
2f0ba790 | 995 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) |
87549141 | 996 | { |
2f0ba790 RW |
997 | struct device *dev = get_cpu_device(cpu); |
998 | ||
67d874c3 | 999 | if (unlikely(!dev)) |
2f0ba790 RW |
1000 | return; |
1001 | ||
1002 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
1003 | return; | |
1004 | ||
26619804 | 1005 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
1006 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
1007 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
1008 | } |
1009 | ||
26619804 VK |
1010 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
1011 | struct device *dev) | |
87549141 | 1012 | { |
26619804 VK |
1013 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1014 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
1015 | } |
1016 | ||
d9612a49 | 1017 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
1018 | { |
1019 | struct freq_attr **drv_attr; | |
909a694e | 1020 | int ret = 0; |
909a694e | 1021 | |
909a694e | 1022 | /* set up files for this cpu device */ |
1c3d85dd | 1023 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1024 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1025 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1026 | if (ret) | |
6d4e81ed | 1027 | return ret; |
909a694e DJ |
1028 | drv_attr++; |
1029 | } | |
1c3d85dd | 1030 | if (cpufreq_driver->get) { |
909a694e DJ |
1031 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1032 | if (ret) | |
6d4e81ed | 1033 | return ret; |
909a694e | 1034 | } |
c034b02e DB |
1035 | |
1036 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1037 | if (ret) | |
6d4e81ed | 1038 | return ret; |
c034b02e | 1039 | |
1c3d85dd | 1040 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1041 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1042 | if (ret) | |
6d4e81ed | 1043 | return ret; |
e2f74f35 | 1044 | } |
909a694e | 1045 | |
26619804 | 1046 | return 0; |
e18f1682 SB |
1047 | } |
1048 | ||
de1df26b RW |
1049 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
1050 | { | |
1051 | return NULL; | |
1052 | } | |
1053 | ||
7f0fa40f | 1054 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1055 | { |
ab05d97a | 1056 | struct cpufreq_governor *gov = NULL, *def_gov = NULL; |
e18f1682 | 1057 | struct cpufreq_policy new_policy; |
e18f1682 | 1058 | |
d5b73cd8 | 1059 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 1060 | |
ab05d97a YH |
1061 | def_gov = cpufreq_default_governor(); |
1062 | ||
1063 | if (has_target()) { | |
1064 | /* | |
1065 | * Update governor of new_policy to the governor used before | |
1066 | * hotplug | |
1067 | */ | |
1068 | gov = find_governor(policy->last_governor); | |
1069 | if (gov) { | |
1070 | pr_debug("Restoring governor %s for cpu %d\n", | |
6e2c89d1 | 1071 | policy->governor->name, policy->cpu); |
ab05d97a YH |
1072 | } else { |
1073 | if (!def_gov) | |
1074 | return -ENODATA; | |
1075 | gov = def_gov; | |
1076 | } | |
1077 | new_policy.governor = gov; | |
de1df26b | 1078 | } else { |
ab05d97a YH |
1079 | /* Use the default policy if there is no last_policy. */ |
1080 | if (policy->last_policy) { | |
69030dd1 | 1081 | new_policy.policy = policy->last_policy; |
ab05d97a YH |
1082 | } else { |
1083 | if (!def_gov) | |
1084 | return -ENODATA; | |
1085 | cpufreq_parse_policy(def_gov->name, &new_policy); | |
1086 | } | |
69030dd1 | 1087 | } |
ab05d97a | 1088 | |
7f0fa40f | 1089 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
1090 | } |
1091 | ||
d9612a49 | 1092 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1093 | { |
9c0ebcf7 | 1094 | int ret = 0; |
fcf80582 | 1095 | |
bb29ae15 VK |
1096 | /* Has this CPU been taken care of already? */ |
1097 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1098 | return 0; | |
1099 | ||
49f18560 | 1100 | down_write(&policy->rwsem); |
45482c70 RW |
1101 | if (has_target()) |
1102 | cpufreq_stop_governor(policy); | |
fcf80582 | 1103 | |
fcf80582 | 1104 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1105 | |
9c0ebcf7 | 1106 | if (has_target()) { |
0a300767 | 1107 | ret = cpufreq_start_governor(policy); |
49f18560 | 1108 | if (ret) |
3de9bdeb | 1109 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1110 | } |
49f18560 VK |
1111 | up_write(&policy->rwsem); |
1112 | return ret; | |
fcf80582 | 1113 | } |
1da177e4 | 1114 | |
c57b25bd | 1115 | void refresh_frequency_limits(struct cpufreq_policy *policy) |
70a59fde | 1116 | { |
67d874c3 | 1117 | struct cpufreq_policy new_policy; |
70a59fde | 1118 | |
67d874c3 VK |
1119 | if (!policy_is_inactive(policy)) { |
1120 | new_policy = *policy; | |
1121 | pr_debug("updating policy for CPU %u\n", policy->cpu); | |
70a59fde | 1122 | |
67d874c3 VK |
1123 | cpufreq_set_policy(policy, &new_policy); |
1124 | } | |
70a59fde | 1125 | } |
c57b25bd | 1126 | EXPORT_SYMBOL(refresh_frequency_limits); |
70a59fde | 1127 | |
11eb69b9 VK |
1128 | static void handle_update(struct work_struct *work) |
1129 | { | |
1130 | struct cpufreq_policy *policy = | |
1131 | container_of(work, struct cpufreq_policy, update); | |
70a59fde VK |
1132 | |
1133 | pr_debug("handle_update for cpu %u called\n", policy->cpu); | |
67d874c3 | 1134 | down_write(&policy->rwsem); |
70a59fde | 1135 | refresh_frequency_limits(policy); |
67d874c3 VK |
1136 | up_write(&policy->rwsem); |
1137 | } | |
1138 | ||
1139 | static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq, | |
1140 | void *data) | |
1141 | { | |
1142 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min); | |
1143 | ||
1144 | schedule_work(&policy->update); | |
1145 | return 0; | |
1146 | } | |
1147 | ||
1148 | static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq, | |
1149 | void *data) | |
1150 | { | |
1151 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max); | |
1152 | ||
1153 | schedule_work(&policy->update); | |
1154 | return 0; | |
1155 | } | |
1156 | ||
1157 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) | |
1158 | { | |
1159 | struct kobject *kobj; | |
1160 | struct completion *cmp; | |
1161 | ||
1162 | down_write(&policy->rwsem); | |
1163 | cpufreq_stats_free_table(policy); | |
1164 | kobj = &policy->kobj; | |
1165 | cmp = &policy->kobj_unregister; | |
1166 | up_write(&policy->rwsem); | |
1167 | kobject_put(kobj); | |
1168 | ||
1169 | /* | |
1170 | * We need to make sure that the underlying kobj is | |
1171 | * actually not referenced anymore by anybody before we | |
1172 | * proceed with unloading. | |
1173 | */ | |
1174 | pr_debug("waiting for dropping of refcount\n"); | |
1175 | wait_for_completion(cmp); | |
1176 | pr_debug("wait complete\n"); | |
fcf80582 | 1177 | } |
1da177e4 | 1178 | |
a34e63b1 | 1179 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1180 | { |
1181 | struct cpufreq_policy *policy; | |
67d874c3 | 1182 | struct device *dev = get_cpu_device(cpu); |
edd4a893 | 1183 | int ret; |
e9698cc5 | 1184 | |
67d874c3 VK |
1185 | if (!dev) |
1186 | return NULL; | |
1187 | ||
e9698cc5 SB |
1188 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1189 | if (!policy) | |
1190 | return NULL; | |
1191 | ||
1192 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1193 | goto err_free_policy; | |
1194 | ||
1195 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1196 | goto err_free_cpumask; | |
1197 | ||
559ed407 RW |
1198 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1199 | goto err_free_rcpumask; | |
1200 | ||
edd4a893 VK |
1201 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1202 | cpufreq_global_kobject, "policy%u", cpu); | |
1203 | if (ret) { | |
67d874c3 | 1204 | dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret); |
2acb9bda RW |
1205 | /* |
1206 | * The entire policy object will be freed below, but the extra | |
1207 | * memory allocated for the kobject name needs to be freed by | |
1208 | * releasing the kobject. | |
1209 | */ | |
4ebe36c9 | 1210 | kobject_put(&policy->kobj); |
edd4a893 VK |
1211 | goto err_free_real_cpus; |
1212 | } | |
1213 | ||
3000ce3c RW |
1214 | freq_constraints_init(&policy->constraints); |
1215 | ||
67d874c3 VK |
1216 | policy->nb_min.notifier_call = cpufreq_notifier_min; |
1217 | policy->nb_max.notifier_call = cpufreq_notifier_max; | |
1218 | ||
3000ce3c RW |
1219 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MIN, |
1220 | &policy->nb_min); | |
67d874c3 VK |
1221 | if (ret) { |
1222 | dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n", | |
1223 | ret, cpumask_pr_args(policy->cpus)); | |
1224 | goto err_kobj_remove; | |
1225 | } | |
1226 | ||
3000ce3c RW |
1227 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MAX, |
1228 | &policy->nb_max); | |
67d874c3 VK |
1229 | if (ret) { |
1230 | dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n", | |
1231 | ret, cpumask_pr_args(policy->cpus)); | |
1232 | goto err_min_qos_notifier; | |
1233 | } | |
1234 | ||
c88a1f8b | 1235 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1236 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1237 | spin_lock_init(&policy->transition_lock); |
1238 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1239 | init_completion(&policy->kobj_unregister); |
1240 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1241 | |
a34e63b1 | 1242 | policy->cpu = cpu; |
e9698cc5 SB |
1243 | return policy; |
1244 | ||
67d874c3 | 1245 | err_min_qos_notifier: |
3000ce3c RW |
1246 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, |
1247 | &policy->nb_min); | |
67d874c3 VK |
1248 | err_kobj_remove: |
1249 | cpufreq_policy_put_kobj(policy); | |
edd4a893 VK |
1250 | err_free_real_cpus: |
1251 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1252 | err_free_rcpumask: |
1253 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1254 | err_free_cpumask: |
1255 | free_cpumask_var(policy->cpus); | |
1256 | err_free_policy: | |
1257 | kfree(policy); | |
1258 | ||
1259 | return NULL; | |
1260 | } | |
1261 | ||
f9f41e3e | 1262 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1263 | { |
988bed09 VK |
1264 | unsigned long flags; |
1265 | int cpu; | |
1266 | ||
1267 | /* Remove policy from list */ | |
1268 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1269 | list_del(&policy->policy_list); | |
1270 | ||
1271 | for_each_cpu(cpu, policy->related_cpus) | |
1272 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1273 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1274 | ||
3000ce3c RW |
1275 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MAX, |
1276 | &policy->nb_max); | |
1277 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, | |
1278 | &policy->nb_min); | |
6a149036 | 1279 | |
6941051d SH |
1280 | /* Cancel any pending policy->update work before freeing the policy. */ |
1281 | cancel_work_sync(&policy->update); | |
6a149036 VK |
1282 | |
1283 | if (policy->max_freq_req) { | |
1284 | /* | |
1285 | * CPUFREQ_CREATE_POLICY notification is sent only after | |
1286 | * successfully adding max_freq_req request. | |
1287 | */ | |
1288 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1289 | CPUFREQ_REMOVE_POLICY, policy); | |
3000ce3c | 1290 | freq_qos_remove_request(policy->max_freq_req); |
6a149036 VK |
1291 | } |
1292 | ||
3000ce3c | 1293 | freq_qos_remove_request(policy->min_freq_req); |
18c49926 | 1294 | kfree(policy->min_freq_req); |
67d874c3 | 1295 | |
f9f41e3e | 1296 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1297 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1298 | free_cpumask_var(policy->related_cpus); |
1299 | free_cpumask_var(policy->cpus); | |
1300 | kfree(policy); | |
1301 | } | |
1302 | ||
0b275352 | 1303 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1304 | { |
7f0c020a | 1305 | struct cpufreq_policy *policy; |
194d99c7 | 1306 | bool new_policy; |
1da177e4 | 1307 | unsigned long flags; |
0b275352 RW |
1308 | unsigned int j; |
1309 | int ret; | |
87549141 | 1310 | |
0b275352 | 1311 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1312 | |
bb29ae15 | 1313 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1314 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1315 | if (policy) { |
9104bb26 | 1316 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1317 | if (!policy_is_inactive(policy)) |
d9612a49 | 1318 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1319 | |
11ce707e | 1320 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1321 | new_policy = false; |
11ce707e RW |
1322 | down_write(&policy->rwsem); |
1323 | policy->cpu = cpu; | |
1324 | policy->governor = NULL; | |
1325 | up_write(&policy->rwsem); | |
1326 | } else { | |
194d99c7 | 1327 | new_policy = true; |
a34e63b1 | 1328 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1329 | if (!policy) |
d4d854d6 | 1330 | return -ENOMEM; |
72368d12 | 1331 | } |
0d66b91e | 1332 | |
91a12e91 VK |
1333 | if (!new_policy && cpufreq_driver->online) { |
1334 | ret = cpufreq_driver->online(policy); | |
1335 | if (ret) { | |
1336 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1337 | __LINE__); | |
1338 | goto out_exit_policy; | |
1339 | } | |
1da177e4 | 1340 | |
91a12e91 VK |
1341 | /* Recover policy->cpus using related_cpus */ |
1342 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1343 | } else { | |
1344 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1345 | |
91a12e91 VK |
1346 | /* |
1347 | * Call driver. From then on the cpufreq must be able | |
1348 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1349 | */ | |
1350 | ret = cpufreq_driver->init(policy); | |
1351 | if (ret) { | |
1352 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1353 | __LINE__); | |
1354 | goto out_free_policy; | |
1355 | } | |
d417e069 | 1356 | |
91a12e91 VK |
1357 | ret = cpufreq_table_validate_and_sort(policy); |
1358 | if (ret) | |
1359 | goto out_exit_policy; | |
6d4e81ed | 1360 | |
4d1f3a5b | 1361 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1362 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1363 | } |
559ed407 | 1364 | |
91a12e91 | 1365 | down_write(&policy->rwsem); |
5a7e56a5 VK |
1366 | /* |
1367 | * affected cpus must always be the one, which are online. We aren't | |
1368 | * managing offline cpus here. | |
1369 | */ | |
1370 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1371 | ||
194d99c7 | 1372 | if (new_policy) { |
2f0ba790 | 1373 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1374 | per_cpu(cpufreq_cpu_data, j) = policy; |
2f0ba790 RW |
1375 | add_cpu_dev_symlink(policy, j); |
1376 | } | |
18c49926 VK |
1377 | |
1378 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1379 | GFP_KERNEL); | |
1380 | if (!policy->min_freq_req) | |
1381 | goto out_destroy_policy; | |
1382 | ||
3000ce3c RW |
1383 | ret = freq_qos_add_request(&policy->constraints, |
1384 | policy->min_freq_req, FREQ_QOS_MIN, | |
1385 | policy->min); | |
18c49926 VK |
1386 | if (ret < 0) { |
1387 | /* | |
3000ce3c | 1388 | * So we don't call freq_qos_remove_request() for an |
18c49926 VK |
1389 | * uninitialized request. |
1390 | */ | |
1391 | kfree(policy->min_freq_req); | |
1392 | policy->min_freq_req = NULL; | |
18c49926 VK |
1393 | goto out_destroy_policy; |
1394 | } | |
1395 | ||
1396 | /* | |
1397 | * This must be initialized right here to avoid calling | |
3000ce3c | 1398 | * freq_qos_remove_request() on uninitialized request in case |
18c49926 VK |
1399 | * of errors. |
1400 | */ | |
1401 | policy->max_freq_req = policy->min_freq_req + 1; | |
1402 | ||
3000ce3c RW |
1403 | ret = freq_qos_add_request(&policy->constraints, |
1404 | policy->max_freq_req, FREQ_QOS_MAX, | |
1405 | policy->max); | |
18c49926 VK |
1406 | if (ret < 0) { |
1407 | policy->max_freq_req = NULL; | |
18c49926 VK |
1408 | goto out_destroy_policy; |
1409 | } | |
6a149036 VK |
1410 | |
1411 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1412 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1413 | } |
652ed95d | 1414 | |
5ddc6d4e | 1415 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1416 | policy->cur = cpufreq_driver->get(policy->cpu); |
1417 | if (!policy->cur) { | |
1418 | pr_err("%s: ->get() failed\n", __func__); | |
d417e069 | 1419 | goto out_destroy_policy; |
da60ce9f VK |
1420 | } |
1421 | } | |
1422 | ||
d3916691 VK |
1423 | /* |
1424 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1425 | * frequency table present with cpufreq core. In such cases CPU might be | |
1426 | * unstable if it has to run on that frequency for long duration of time | |
1427 | * and so its better to set it to a frequency which is specified in | |
1428 | * freq-table. This also makes cpufreq stats inconsistent as | |
1429 | * cpufreq-stats would fail to register because current frequency of CPU | |
1430 | * isn't found in freq-table. | |
1431 | * | |
1432 | * Because we don't want this change to effect boot process badly, we go | |
1433 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1434 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1435 | * is initialized to zero). | |
1436 | * | |
1437 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1438 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1439 | * equal to target-freq. | |
1440 | */ | |
1441 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1442 | && has_target()) { | |
1443 | /* Are we running at unknown frequency ? */ | |
1444 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1445 | if (ret == -EINVAL) { | |
1446 | /* Warn user and fix it */ | |
1447 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1448 | __func__, policy->cpu, policy->cur); | |
1449 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1450 | CPUFREQ_RELATION_L); | |
1451 | ||
1452 | /* | |
1453 | * Reaching here after boot in a few seconds may not | |
1454 | * mean that system will remain stable at "unknown" | |
1455 | * frequency for longer duration. Hence, a BUG_ON(). | |
1456 | */ | |
1457 | BUG_ON(ret); | |
1458 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1459 | __func__, policy->cpu, policy->cur); | |
1460 | } | |
1461 | } | |
1462 | ||
194d99c7 | 1463 | if (new_policy) { |
d9612a49 | 1464 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1465 | if (ret) |
d417e069 | 1466 | goto out_destroy_policy; |
1aefc75b RW |
1467 | |
1468 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1469 | |
988bed09 VK |
1470 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1471 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1472 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1473 | } | |
9515f4d6 | 1474 | |
7f0fa40f VK |
1475 | ret = cpufreq_init_policy(policy); |
1476 | if (ret) { | |
1477 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1478 | __func__, cpu, ret); | |
d417e069 | 1479 | goto out_destroy_policy; |
08fd8c1c | 1480 | } |
e18f1682 | 1481 | |
4e97b631 | 1482 | up_write(&policy->rwsem); |
08fd8c1c | 1483 | |
038c5b3e | 1484 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1485 | |
7c45cf31 VK |
1486 | /* Callback for handling stuff after policy is ready */ |
1487 | if (cpufreq_driver->ready) | |
1488 | cpufreq_driver->ready(policy); | |
1489 | ||
bcc61569 | 1490 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1491 | policy->cdev = of_cpufreq_cooling_register(policy); |
1492 | ||
2d06d8c4 | 1493 | pr_debug("initialization complete\n"); |
87c32271 | 1494 | |
1da177e4 LT |
1495 | return 0; |
1496 | ||
d417e069 | 1497 | out_destroy_policy: |
b24b6478 VK |
1498 | for_each_cpu(j, policy->real_cpus) |
1499 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1500 | ||
7106e02b PB |
1501 | up_write(&policy->rwsem); |
1502 | ||
d417e069 | 1503 | out_exit_policy: |
da60ce9f VK |
1504 | if (cpufreq_driver->exit) |
1505 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1506 | |
8101f997 | 1507 | out_free_policy: |
f9f41e3e | 1508 | cpufreq_policy_free(policy); |
1da177e4 LT |
1509 | return ret; |
1510 | } | |
1511 | ||
0b275352 RW |
1512 | /** |
1513 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1514 | * @dev: CPU device. | |
1515 | * @sif: Subsystem interface structure pointer (not used) | |
1516 | */ | |
1517 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1518 | { | |
a794d613 | 1519 | struct cpufreq_policy *policy; |
0b275352 | 1520 | unsigned cpu = dev->id; |
26619804 | 1521 | int ret; |
0b275352 RW |
1522 | |
1523 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1524 | ||
26619804 VK |
1525 | if (cpu_online(cpu)) { |
1526 | ret = cpufreq_online(cpu); | |
1527 | if (ret) | |
1528 | return ret; | |
1529 | } | |
0b275352 | 1530 | |
26619804 | 1531 | /* Create sysfs link on CPU registration */ |
a794d613 | 1532 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 RW |
1533 | if (policy) |
1534 | add_cpu_dev_symlink(policy, cpu); | |
26619804 | 1535 | |
2f0ba790 | 1536 | return 0; |
1da177e4 LT |
1537 | } |
1538 | ||
27622b06 | 1539 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1540 | { |
3a3e9e06 | 1541 | struct cpufreq_policy *policy; |
69cee714 | 1542 | int ret; |
1da177e4 | 1543 | |
b8eed8af | 1544 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1545 | |
988bed09 | 1546 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1547 | if (!policy) { |
b8eed8af | 1548 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1549 | return 0; |
1da177e4 | 1550 | } |
1da177e4 | 1551 | |
49f18560 | 1552 | down_write(&policy->rwsem); |
45482c70 RW |
1553 | if (has_target()) |
1554 | cpufreq_stop_governor(policy); | |
1da177e4 | 1555 | |
9591becb | 1556 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1557 | |
9591becb VK |
1558 | if (policy_is_inactive(policy)) { |
1559 | if (has_target()) | |
1560 | strncpy(policy->last_governor, policy->governor->name, | |
1561 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1562 | else |
1563 | policy->last_policy = policy->policy; | |
9591becb VK |
1564 | } else if (cpu == policy->cpu) { |
1565 | /* Nominate new CPU */ | |
1566 | policy->cpu = cpumask_any(policy->cpus); | |
1567 | } | |
084f3493 | 1568 | |
9591becb VK |
1569 | /* Start governor again for active policy */ |
1570 | if (!policy_is_inactive(policy)) { | |
1571 | if (has_target()) { | |
0a300767 | 1572 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1573 | if (ret) |
1574 | pr_err("%s: Failed to start governor\n", __func__); | |
1575 | } | |
cedb70af | 1576 | |
49f18560 | 1577 | goto unlock; |
cedb70af SB |
1578 | } |
1579 | ||
bcc61569 | 1580 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1581 | cpufreq_cooling_unregister(policy->cdev); |
1582 | policy->cdev = NULL; | |
1583 | } | |
1584 | ||
69cee714 VK |
1585 | if (cpufreq_driver->stop_cpu) |
1586 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1587 | |
36be3418 RW |
1588 | if (has_target()) |
1589 | cpufreq_exit_governor(policy); | |
1da177e4 | 1590 | |
87549141 | 1591 | /* |
91a12e91 VK |
1592 | * Perform the ->offline() during light-weight tear-down, as |
1593 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1594 | */ |
91a12e91 VK |
1595 | if (cpufreq_driver->offline) { |
1596 | cpufreq_driver->offline(policy); | |
1597 | } else if (cpufreq_driver->exit) { | |
87549141 | 1598 | cpufreq_driver->exit(policy); |
55582bcc SP |
1599 | policy->freq_table = NULL; |
1600 | } | |
49f18560 VK |
1601 | |
1602 | unlock: | |
1603 | up_write(&policy->rwsem); | |
27622b06 | 1604 | return 0; |
1da177e4 LT |
1605 | } |
1606 | ||
cedb70af | 1607 | /** |
27a862e9 | 1608 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1609 | * |
1610 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1611 | */ |
71db87ba | 1612 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1613 | { |
8a25a2fd | 1614 | unsigned int cpu = dev->id; |
559ed407 | 1615 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1616 | |
559ed407 | 1617 | if (!policy) |
1af115d6 | 1618 | return; |
87549141 | 1619 | |
69cee714 VK |
1620 | if (cpu_online(cpu)) |
1621 | cpufreq_offline(cpu); | |
87549141 | 1622 | |
559ed407 | 1623 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1624 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1625 | |
91a12e91 VK |
1626 | if (cpumask_empty(policy->real_cpus)) { |
1627 | /* We did light-weight exit earlier, do full tear down now */ | |
1628 | if (cpufreq_driver->offline) | |
1629 | cpufreq_driver->exit(policy); | |
1630 | ||
f9f41e3e | 1631 | cpufreq_policy_free(policy); |
91a12e91 | 1632 | } |
5a01f2e8 VP |
1633 | } |
1634 | ||
1da177e4 | 1635 | /** |
bb176f7d VK |
1636 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1637 | * in deep trouble. | |
a1e1dc41 | 1638 | * @policy: policy managing CPUs |
1da177e4 LT |
1639 | * @new_freq: CPU frequency the CPU actually runs at |
1640 | * | |
29464f28 DJ |
1641 | * We adjust to current frequency first, and need to clean up later. |
1642 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1643 | */ |
a1e1dc41 | 1644 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1645 | unsigned int new_freq) |
1da177e4 LT |
1646 | { |
1647 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1648 | |
e837f9b5 | 1649 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1650 | policy->cur, new_freq); |
1da177e4 | 1651 | |
a1e1dc41 | 1652 | freqs.old = policy->cur; |
1da177e4 | 1653 | freqs.new = new_freq; |
b43a7ffb | 1654 | |
8fec051e VK |
1655 | cpufreq_freq_transition_begin(policy, &freqs); |
1656 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1657 | } |
1658 | ||
5980752e VK |
1659 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1660 | { | |
1661 | unsigned int new_freq; | |
1662 | ||
1663 | new_freq = cpufreq_driver->get(policy->cpu); | |
1664 | if (!new_freq) | |
1665 | return 0; | |
1666 | ||
1667 | /* | |
1668 | * If fast frequency switching is used with the given policy, the check | |
1669 | * against policy->cur is pointless, so skip it in that case. | |
1670 | */ | |
1671 | if (policy->fast_switch_enabled || !has_target()) | |
1672 | return new_freq; | |
1673 | ||
1674 | if (policy->cur != new_freq) { | |
1675 | cpufreq_out_of_sync(policy, new_freq); | |
1676 | if (update) | |
1677 | schedule_work(&policy->update); | |
1678 | } | |
1679 | ||
1680 | return new_freq; | |
1681 | } | |
1682 | ||
32ee8c3e | 1683 | /** |
4ab70df4 | 1684 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1685 | * @cpu: CPU number |
1686 | * | |
1687 | * This is the last known freq, without actually getting it from the driver. | |
1688 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1689 | */ | |
1690 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1691 | { | |
9e21ba8b | 1692 | struct cpufreq_policy *policy; |
e08f5f5b | 1693 | unsigned int ret_freq = 0; |
c75361c0 | 1694 | unsigned long flags; |
95235ca2 | 1695 | |
c75361c0 RC |
1696 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1697 | ||
1698 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1699 | ret_freq = cpufreq_driver->get(cpu); | |
1700 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1701 | return ret_freq; | |
1702 | } | |
1703 | ||
1704 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1705 | |
1706 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1707 | if (policy) { |
e08f5f5b | 1708 | ret_freq = policy->cur; |
95235ca2 VP |
1709 | cpufreq_cpu_put(policy); |
1710 | } | |
1711 | ||
4d34a67d | 1712 | return ret_freq; |
95235ca2 VP |
1713 | } |
1714 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1715 | ||
3d737108 JB |
1716 | /** |
1717 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1718 | * @cpu: CPU number | |
1719 | * | |
1720 | * Just return the max possible frequency for a given CPU. | |
1721 | */ | |
1722 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1723 | { | |
1724 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1725 | unsigned int ret_freq = 0; | |
1726 | ||
1727 | if (policy) { | |
1728 | ret_freq = policy->max; | |
1729 | cpufreq_cpu_put(policy); | |
1730 | } | |
1731 | ||
1732 | return ret_freq; | |
1733 | } | |
1734 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1735 | ||
d92d50a4 | 1736 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1737 | { |
4db7c34c | 1738 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1739 | return 0; |
1da177e4 | 1740 | |
5980752e | 1741 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1742 | } |
1da177e4 | 1743 | |
5a01f2e8 VP |
1744 | /** |
1745 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1746 | * @cpu: CPU number | |
1747 | * | |
1748 | * Get the CPU current (static) CPU frequency | |
1749 | */ | |
1750 | unsigned int cpufreq_get(unsigned int cpu) | |
1751 | { | |
999976e0 | 1752 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1753 | unsigned int ret_freq = 0; |
5a01f2e8 | 1754 | |
999976e0 AP |
1755 | if (policy) { |
1756 | down_read(&policy->rwsem); | |
4db7c34c YH |
1757 | if (cpufreq_driver->get) |
1758 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1759 | up_read(&policy->rwsem); |
5a01f2e8 | 1760 | |
999976e0 AP |
1761 | cpufreq_cpu_put(policy); |
1762 | } | |
6eed9404 | 1763 | |
4d34a67d | 1764 | return ret_freq; |
1da177e4 LT |
1765 | } |
1766 | EXPORT_SYMBOL(cpufreq_get); | |
1767 | ||
8a25a2fd KS |
1768 | static struct subsys_interface cpufreq_interface = { |
1769 | .name = "cpufreq", | |
1770 | .subsys = &cpu_subsys, | |
1771 | .add_dev = cpufreq_add_dev, | |
1772 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1773 | }; |
1774 | ||
e28867ea VK |
1775 | /* |
1776 | * In case platform wants some specific frequency to be configured | |
1777 | * during suspend.. | |
1778 | */ | |
1779 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1780 | { | |
1781 | int ret; | |
1782 | ||
1783 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1784 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1785 | return 0; | |
e28867ea VK |
1786 | } |
1787 | ||
1788 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1789 | policy->suspend_freq); | |
1790 | ||
1791 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1792 | CPUFREQ_RELATION_H); | |
1793 | if (ret) | |
1794 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1795 | __func__, policy->suspend_freq, ret); | |
1796 | ||
1797 | return ret; | |
1798 | } | |
1799 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1800 | ||
42d4dc3f | 1801 | /** |
2f0aea93 | 1802 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1803 | * |
2f0aea93 VK |
1804 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1805 | * as some platforms can't change frequency after this point in suspend cycle. | |
1806 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1807 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1808 | */ |
2f0aea93 | 1809 | void cpufreq_suspend(void) |
42d4dc3f | 1810 | { |
3a3e9e06 | 1811 | struct cpufreq_policy *policy; |
42d4dc3f | 1812 | |
2f0aea93 VK |
1813 | if (!cpufreq_driver) |
1814 | return; | |
42d4dc3f | 1815 | |
ba41e1bc | 1816 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1817 | goto suspend; |
42d4dc3f | 1818 | |
2f0aea93 VK |
1819 | pr_debug("%s: Suspending Governors\n", __func__); |
1820 | ||
f963735a | 1821 | for_each_active_policy(policy) { |
ba41e1bc RW |
1822 | if (has_target()) { |
1823 | down_write(&policy->rwsem); | |
45482c70 | 1824 | cpufreq_stop_governor(policy); |
ba41e1bc | 1825 | up_write(&policy->rwsem); |
ba41e1bc RW |
1826 | } |
1827 | ||
1828 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1829 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1830 | cpufreq_driver->name); | |
42d4dc3f | 1831 | } |
b1b12bab VK |
1832 | |
1833 | suspend: | |
1834 | cpufreq_suspended = true; | |
42d4dc3f BH |
1835 | } |
1836 | ||
1da177e4 | 1837 | /** |
2f0aea93 | 1838 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1839 | * |
2f0aea93 VK |
1840 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1841 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1842 | */ |
2f0aea93 | 1843 | void cpufreq_resume(void) |
1da177e4 | 1844 | { |
3a3e9e06 | 1845 | struct cpufreq_policy *policy; |
49f18560 | 1846 | int ret; |
1da177e4 | 1847 | |
2f0aea93 | 1848 | if (!cpufreq_driver) |
703cbaa6 BY |
1849 | return; |
1850 | ||
1851 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1852 | return; |
1da177e4 | 1853 | |
8e30444e LT |
1854 | cpufreq_suspended = false; |
1855 | ||
ba41e1bc | 1856 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1857 | return; |
1da177e4 | 1858 | |
2f0aea93 | 1859 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1860 | |
f963735a | 1861 | for_each_active_policy(policy) { |
49f18560 | 1862 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1863 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1864 | policy); | |
ba41e1bc | 1865 | } else if (has_target()) { |
49f18560 | 1866 | down_write(&policy->rwsem); |
0a300767 | 1867 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1868 | up_write(&policy->rwsem); |
1869 | ||
1870 | if (ret) | |
1871 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1872 | __func__, policy); | |
1873 | } | |
2f0aea93 VK |
1874 | } |
1875 | } | |
1da177e4 | 1876 | |
9d95046e BP |
1877 | /** |
1878 | * cpufreq_get_current_driver - return current driver's name | |
1879 | * | |
1880 | * Return the name string of the currently loaded cpufreq driver | |
1881 | * or NULL, if none. | |
1882 | */ | |
1883 | const char *cpufreq_get_current_driver(void) | |
1884 | { | |
1c3d85dd RW |
1885 | if (cpufreq_driver) |
1886 | return cpufreq_driver->name; | |
1887 | ||
1888 | return NULL; | |
9d95046e BP |
1889 | } |
1890 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1891 | |
51315cdf TP |
1892 | /** |
1893 | * cpufreq_get_driver_data - return current driver data | |
1894 | * | |
1895 | * Return the private data of the currently loaded cpufreq | |
1896 | * driver, or NULL if no cpufreq driver is loaded. | |
1897 | */ | |
1898 | void *cpufreq_get_driver_data(void) | |
1899 | { | |
1900 | if (cpufreq_driver) | |
1901 | return cpufreq_driver->driver_data; | |
1902 | ||
1903 | return NULL; | |
1904 | } | |
1905 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1906 | ||
1da177e4 LT |
1907 | /********************************************************************* |
1908 | * NOTIFIER LISTS INTERFACE * | |
1909 | *********************************************************************/ | |
1910 | ||
1911 | /** | |
1912 | * cpufreq_register_notifier - register a driver with cpufreq | |
1913 | * @nb: notifier function to register | |
1914 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1915 | * | |
32ee8c3e | 1916 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1917 | * are notified about clock rate changes (once before and once after |
1918 | * the transition), or a list of drivers that are notified about | |
1919 | * changes in cpufreq policy. | |
1920 | * | |
1921 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1922 | * blocking_notifier_chain_register. |
1da177e4 LT |
1923 | */ |
1924 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1925 | { | |
1926 | int ret; | |
1927 | ||
d5aaffa9 DB |
1928 | if (cpufreq_disabled()) |
1929 | return -EINVAL; | |
1930 | ||
1da177e4 LT |
1931 | switch (list) { |
1932 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1933 | mutex_lock(&cpufreq_fast_switch_lock); |
1934 | ||
1935 | if (cpufreq_fast_switch_count > 0) { | |
1936 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1937 | return -EBUSY; | |
1938 | } | |
b4dfdbb3 | 1939 | ret = srcu_notifier_chain_register( |
e041c683 | 1940 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1941 | if (!ret) |
1942 | cpufreq_fast_switch_count--; | |
1943 | ||
1944 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1945 | break; |
1946 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1947 | ret = blocking_notifier_chain_register( |
1948 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1949 | break; |
1950 | default: | |
1951 | ret = -EINVAL; | |
1952 | } | |
1da177e4 LT |
1953 | |
1954 | return ret; | |
1955 | } | |
1956 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1957 | ||
1da177e4 LT |
1958 | /** |
1959 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1960 | * @nb: notifier block to be unregistered | |
bb176f7d | 1961 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1962 | * |
1963 | * Remove a driver from the CPU frequency notifier list. | |
1964 | * | |
1965 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1966 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1967 | */ |
1968 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1969 | { | |
1970 | int ret; | |
1971 | ||
d5aaffa9 DB |
1972 | if (cpufreq_disabled()) |
1973 | return -EINVAL; | |
1974 | ||
1da177e4 LT |
1975 | switch (list) { |
1976 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1977 | mutex_lock(&cpufreq_fast_switch_lock); |
1978 | ||
b4dfdbb3 | 1979 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1980 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1981 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
1982 | cpufreq_fast_switch_count++; | |
1983 | ||
1984 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1985 | break; |
1986 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1987 | ret = blocking_notifier_chain_unregister( |
1988 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1989 | break; |
1990 | default: | |
1991 | ret = -EINVAL; | |
1992 | } | |
1da177e4 LT |
1993 | |
1994 | return ret; | |
1995 | } | |
1996 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1997 | ||
1998 | ||
1999 | /********************************************************************* | |
2000 | * GOVERNORS * | |
2001 | *********************************************************************/ | |
2002 | ||
b7898fda RW |
2003 | /** |
2004 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
2005 | * @policy: cpufreq policy to switch the frequency for. | |
2006 | * @target_freq: New frequency to set (may be approximate). | |
2007 | * | |
2008 | * Carry out a fast frequency switch without sleeping. | |
2009 | * | |
2010 | * The driver's ->fast_switch() callback invoked by this function must be | |
2011 | * suitable for being called from within RCU-sched read-side critical sections | |
2012 | * and it is expected to select the minimum available frequency greater than or | |
2013 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2014 | * | |
2015 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2016 | * | |
2017 | * Governors calling this function must guarantee that it will never be invoked | |
2018 | * twice in parallel for the same policy and that it will never be called in | |
2019 | * parallel with either ->target() or ->target_index() for the same policy. | |
2020 | * | |
209887e6 VK |
2021 | * Returns the actual frequency set for the CPU. |
2022 | * | |
2023 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2024 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2025 | */ |
2026 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2027 | unsigned int target_freq) | |
2028 | { | |
b9af6948 | 2029 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
b7898fda RW |
2030 | |
2031 | return cpufreq_driver->fast_switch(policy, target_freq); | |
2032 | } | |
2033 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2034 | ||
1c03a2d0 VK |
2035 | /* Must set freqs->new to intermediate frequency */ |
2036 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2037 | struct cpufreq_freqs *freqs, int index) | |
2038 | { | |
2039 | int ret; | |
2040 | ||
2041 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2042 | ||
2043 | /* We don't need to switch to intermediate freq */ | |
2044 | if (!freqs->new) | |
2045 | return 0; | |
2046 | ||
2047 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2048 | __func__, policy->cpu, freqs->old, freqs->new); | |
2049 | ||
2050 | cpufreq_freq_transition_begin(policy, freqs); | |
2051 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2052 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2053 | ||
2054 | if (ret) | |
2055 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2056 | __func__, ret); | |
2057 | ||
2058 | return ret; | |
2059 | } | |
2060 | ||
23727845 | 2061 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2062 | { |
1c03a2d0 VK |
2063 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
2064 | unsigned int intermediate_freq = 0; | |
23727845 | 2065 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2066 | int retval = -EINVAL; |
2067 | bool notify; | |
2068 | ||
23727845 VK |
2069 | if (newfreq == policy->cur) |
2070 | return 0; | |
2071 | ||
8d65775d | 2072 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2073 | if (notify) { |
1c03a2d0 VK |
2074 | /* Handle switching to intermediate frequency */ |
2075 | if (cpufreq_driver->get_intermediate) { | |
2076 | retval = __target_intermediate(policy, &freqs, index); | |
2077 | if (retval) | |
2078 | return retval; | |
2079 | ||
2080 | intermediate_freq = freqs.new; | |
2081 | /* Set old freq to intermediate */ | |
2082 | if (intermediate_freq) | |
2083 | freqs.old = freqs.new; | |
2084 | } | |
8d65775d | 2085 | |
23727845 | 2086 | freqs.new = newfreq; |
8d65775d VK |
2087 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2088 | __func__, policy->cpu, freqs.old, freqs.new); | |
2089 | ||
2090 | cpufreq_freq_transition_begin(policy, &freqs); | |
2091 | } | |
2092 | ||
2093 | retval = cpufreq_driver->target_index(policy, index); | |
2094 | if (retval) | |
2095 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2096 | retval); | |
2097 | ||
1c03a2d0 | 2098 | if (notify) { |
8d65775d VK |
2099 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2100 | ||
1c03a2d0 VK |
2101 | /* |
2102 | * Failed after setting to intermediate freq? Driver should have | |
2103 | * reverted back to initial frequency and so should we. Check | |
2104 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2105 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2106 | */ |
2107 | if (unlikely(retval && intermediate_freq)) { | |
2108 | freqs.old = intermediate_freq; | |
2109 | freqs.new = policy->restore_freq; | |
2110 | cpufreq_freq_transition_begin(policy, &freqs); | |
2111 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2112 | } | |
2113 | } | |
2114 | ||
8d65775d VK |
2115 | return retval; |
2116 | } | |
2117 | ||
1da177e4 LT |
2118 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2119 | unsigned int target_freq, | |
2120 | unsigned int relation) | |
2121 | { | |
7249924e | 2122 | unsigned int old_target_freq = target_freq; |
d218ed77 | 2123 | int index; |
c32b6b8e | 2124 | |
a7b422cd KRW |
2125 | if (cpufreq_disabled()) |
2126 | return -ENODEV; | |
2127 | ||
7249924e | 2128 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 2129 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
2130 | |
2131 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2132 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2133 | |
9c0ebcf7 VK |
2134 | /* |
2135 | * This might look like a redundant call as we are checking it again | |
2136 | * after finding index. But it is left intentionally for cases where | |
2137 | * exactly same freq is called again and so we can save on few function | |
2138 | * calls. | |
2139 | */ | |
5a1c0228 VK |
2140 | if (target_freq == policy->cur) |
2141 | return 0; | |
2142 | ||
1c03a2d0 VK |
2143 | /* Save last value to restore later on errors */ |
2144 | policy->restore_freq = policy->cur; | |
2145 | ||
1c3d85dd | 2146 | if (cpufreq_driver->target) |
6019d23a | 2147 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 2148 | |
6019d23a RW |
2149 | if (!cpufreq_driver->target_index) |
2150 | return -EINVAL; | |
9c0ebcf7 | 2151 | |
d218ed77 | 2152 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 2153 | |
23727845 | 2154 | return __target_index(policy, index); |
1da177e4 LT |
2155 | } |
2156 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2157 | ||
1da177e4 LT |
2158 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2159 | unsigned int target_freq, | |
2160 | unsigned int relation) | |
2161 | { | |
62c23a89 | 2162 | int ret; |
1da177e4 | 2163 | |
ad7722da | 2164 | down_write(&policy->rwsem); |
1da177e4 LT |
2165 | |
2166 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2167 | ||
ad7722da | 2168 | up_write(&policy->rwsem); |
1da177e4 | 2169 | |
1da177e4 LT |
2170 | return ret; |
2171 | } | |
2172 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2173 | ||
de1df26b RW |
2174 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2175 | { | |
2176 | return NULL; | |
2177 | } | |
2178 | ||
a92604b4 | 2179 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2180 | { |
cc993cab | 2181 | int ret; |
6afde10c | 2182 | |
2f0aea93 VK |
2183 | /* Don't start any governor operations if we are entering suspend */ |
2184 | if (cpufreq_suspended) | |
2185 | return 0; | |
cb57720b EZ |
2186 | /* |
2187 | * Governor might not be initiated here if ACPI _PPC changed | |
2188 | * notification happened, so check it. | |
2189 | */ | |
2190 | if (!policy->governor) | |
2191 | return -EINVAL; | |
2f0aea93 | 2192 | |
ed4676e2 VK |
2193 | /* Platform doesn't want dynamic frequency switching ? */ |
2194 | if (policy->governor->dynamic_switching && | |
fc4c709f | 2195 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2196 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2197 | ||
2198 | if (gov) { | |
fe829ed8 | 2199 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2200 | policy->governor->name, gov->name); |
6afde10c | 2201 | policy->governor = gov; |
de1df26b RW |
2202 | } else { |
2203 | return -EINVAL; | |
6afde10c | 2204 | } |
1c256245 | 2205 | } |
1da177e4 | 2206 | |
a92604b4 RW |
2207 | if (!try_module_get(policy->governor->owner)) |
2208 | return -EINVAL; | |
95731ebb | 2209 | |
a92604b4 | 2210 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2211 | |
e788892b RW |
2212 | if (policy->governor->init) { |
2213 | ret = policy->governor->init(policy); | |
2214 | if (ret) { | |
36be3418 | 2215 | module_put(policy->governor->owner); |
e788892b RW |
2216 | return ret; |
2217 | } | |
36be3418 | 2218 | } |
1da177e4 | 2219 | |
a92604b4 RW |
2220 | return 0; |
2221 | } | |
2222 | ||
2223 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2224 | { | |
2225 | if (cpufreq_suspended || !policy->governor) | |
2226 | return; | |
2227 | ||
2228 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2229 | ||
e788892b RW |
2230 | if (policy->governor->exit) |
2231 | policy->governor->exit(policy); | |
a92604b4 | 2232 | |
a92604b4 | 2233 | module_put(policy->governor->owner); |
1da177e4 LT |
2234 | } |
2235 | ||
0a300767 RW |
2236 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
2237 | { | |
2238 | int ret; | |
2239 | ||
a92604b4 RW |
2240 | if (cpufreq_suspended) |
2241 | return 0; | |
2242 | ||
2243 | if (!policy->governor) | |
2244 | return -EINVAL; | |
2245 | ||
2246 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2247 | ||
407d0fff | 2248 | if (cpufreq_driver->get) |
5980752e | 2249 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2250 | |
e788892b RW |
2251 | if (policy->governor->start) { |
2252 | ret = policy->governor->start(policy); | |
2253 | if (ret) | |
2254 | return ret; | |
2255 | } | |
2256 | ||
2257 | if (policy->governor->limits) | |
2258 | policy->governor->limits(policy); | |
d6ff44d6 | 2259 | |
d6ff44d6 | 2260 | return 0; |
0a300767 RW |
2261 | } |
2262 | ||
a92604b4 RW |
2263 | static void cpufreq_stop_governor(struct cpufreq_policy *policy) |
2264 | { | |
2265 | if (cpufreq_suspended || !policy->governor) | |
2266 | return; | |
2267 | ||
2268 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2269 | ||
e788892b RW |
2270 | if (policy->governor->stop) |
2271 | policy->governor->stop(policy); | |
a92604b4 RW |
2272 | } |
2273 | ||
2274 | static void cpufreq_governor_limits(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->limits) |
2282 | policy->governor->limits(policy); | |
0a300767 RW |
2283 | } |
2284 | ||
1da177e4 LT |
2285 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2286 | { | |
3bcb09a3 | 2287 | int err; |
1da177e4 LT |
2288 | |
2289 | if (!governor) | |
2290 | return -EINVAL; | |
2291 | ||
a7b422cd KRW |
2292 | if (cpufreq_disabled()) |
2293 | return -ENODEV; | |
2294 | ||
3fc54d37 | 2295 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2296 | |
3bcb09a3 | 2297 | err = -EBUSY; |
42f91fa1 | 2298 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2299 | err = 0; |
2300 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2301 | } |
1da177e4 | 2302 | |
32ee8c3e | 2303 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2304 | return err; |
1da177e4 LT |
2305 | } |
2306 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2307 | ||
1da177e4 LT |
2308 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2309 | { | |
4573237b VK |
2310 | struct cpufreq_policy *policy; |
2311 | unsigned long flags; | |
90e41bac | 2312 | |
1da177e4 LT |
2313 | if (!governor) |
2314 | return; | |
2315 | ||
a7b422cd KRW |
2316 | if (cpufreq_disabled()) |
2317 | return; | |
2318 | ||
4573237b VK |
2319 | /* clear last_governor for all inactive policies */ |
2320 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2321 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2322 | if (!strcmp(policy->last_governor, governor->name)) { |
2323 | policy->governor = NULL; | |
4573237b | 2324 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2325 | } |
90e41bac | 2326 | } |
4573237b | 2327 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2328 | |
3fc54d37 | 2329 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2330 | list_del(&governor->governor_list); |
3fc54d37 | 2331 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2332 | } |
2333 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2334 | ||
2335 | ||
1da177e4 LT |
2336 | /********************************************************************* |
2337 | * POLICY INTERFACE * | |
2338 | *********************************************************************/ | |
2339 | ||
2340 | /** | |
2341 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2342 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2343 | * is written | |
1da177e4 LT |
2344 | * |
2345 | * Reads the current cpufreq policy. | |
2346 | */ | |
2347 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2348 | { | |
2349 | struct cpufreq_policy *cpu_policy; | |
2350 | if (!policy) | |
2351 | return -EINVAL; | |
2352 | ||
2353 | cpu_policy = cpufreq_cpu_get(cpu); | |
2354 | if (!cpu_policy) | |
2355 | return -EINVAL; | |
2356 | ||
d5b73cd8 | 2357 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2358 | |
2359 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2360 | return 0; |
2361 | } | |
2362 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2363 | ||
a0dbb819 RW |
2364 | /** |
2365 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2366 | * @policy: Policy object to modify. | |
2367 | * @new_policy: New policy data. | |
2368 | * | |
df0eea44 VK |
2369 | * Pass @new_policy to the cpufreq driver's ->verify() callback. Next, copy the |
2370 | * min and max parameters of @new_policy to @policy and either invoke the | |
2371 | * driver's ->setpolicy() callback (if present) or carry out a governor update | |
2372 | * for @policy. That is, run the current governor's ->limits() callback (if the | |
2373 | * governor field in @new_policy points to the same object as the one in | |
2374 | * @policy) or replace the governor for @policy with the new one stored in | |
2375 | * @new_policy. | |
a0dbb819 RW |
2376 | * |
2377 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2378 | */ |
9083e498 RW |
2379 | int cpufreq_set_policy(struct cpufreq_policy *policy, |
2380 | struct cpufreq_policy *new_policy) | |
1da177e4 | 2381 | { |
d9a789c7 RW |
2382 | struct cpufreq_governor *old_gov; |
2383 | int ret; | |
1da177e4 | 2384 | |
e837f9b5 JP |
2385 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2386 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2387 | |
d5b73cd8 | 2388 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2389 | |
fba9573b | 2390 | /* |
67d874c3 VK |
2391 | * PM QoS framework collects all the requests from users and provide us |
2392 | * the final aggregated value here. | |
2393 | */ | |
3000ce3c RW |
2394 | new_policy->min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); |
2395 | new_policy->max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); | |
9c9a43ed | 2396 | |
737ffb27 VK |
2397 | /* |
2398 | * Verify that the CPU speed can be set within these limits and make sure | |
2399 | * that min <= max. | |
2400 | */ | |
3a3e9e06 | 2401 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2402 | if (ret) |
d9a789c7 | 2403 | return ret; |
1da177e4 | 2404 | |
3a3e9e06 VK |
2405 | policy->min = new_policy->min; |
2406 | policy->max = new_policy->max; | |
601b2185 | 2407 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2408 | |
e3c06236 SM |
2409 | policy->cached_target_freq = UINT_MAX; |
2410 | ||
2d06d8c4 | 2411 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2412 | policy->min, policy->max); |
1da177e4 | 2413 | |
1c3d85dd | 2414 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2415 | policy->policy = new_policy->policy; |
2d06d8c4 | 2416 | pr_debug("setting range\n"); |
167a38dc | 2417 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2418 | } |
1da177e4 | 2419 | |
0a300767 | 2420 | if (new_policy->governor == policy->governor) { |
2bb4059e | 2421 | pr_debug("governor limits update\n"); |
a92604b4 | 2422 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2423 | return 0; |
0a300767 | 2424 | } |
7bd353a9 | 2425 | |
d9a789c7 RW |
2426 | pr_debug("governor switch\n"); |
2427 | ||
2428 | /* save old, working values */ | |
2429 | old_gov = policy->governor; | |
2430 | /* end old governor */ | |
2431 | if (old_gov) { | |
45482c70 | 2432 | cpufreq_stop_governor(policy); |
36be3418 | 2433 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2434 | } |
2435 | ||
d9a789c7 RW |
2436 | /* start new governor */ |
2437 | policy->governor = new_policy->governor; | |
a92604b4 | 2438 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2439 | if (!ret) { |
0a300767 RW |
2440 | ret = cpufreq_start_governor(policy); |
2441 | if (!ret) { | |
2bb4059e | 2442 | pr_debug("governor change\n"); |
531b5c9f | 2443 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2444 | return 0; |
2445 | } | |
b7898fda | 2446 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2447 | } |
2448 | ||
2449 | /* new governor failed, so re-start old one */ | |
2450 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2451 | if (old_gov) { | |
2452 | policy->governor = old_gov; | |
a92604b4 | 2453 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2454 | policy->governor = NULL; |
2455 | else | |
0a300767 | 2456 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2457 | } |
2458 | ||
4bc384ae | 2459 | return ret; |
1da177e4 LT |
2460 | } |
2461 | ||
1da177e4 | 2462 | /** |
a0dbb819 RW |
2463 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2464 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2465 | * |
a0dbb819 | 2466 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2467 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2468 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2469 | * for the policy in question, among other things. | |
1da177e4 | 2470 | */ |
30248fef | 2471 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2472 | { |
540a3758 | 2473 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2474 | |
fefa8ff8 | 2475 | if (!policy) |
30248fef | 2476 | return; |
1da177e4 | 2477 | |
bb176f7d VK |
2478 | /* |
2479 | * BIOS might change freq behind our back | |
2480 | * -> ask driver for current freq and notify governors about a change | |
2481 | */ | |
5ddc6d4e | 2482 | if (cpufreq_driver->get && has_target() && |
5980752e | 2483 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2484 | goto unlock; |
30248fef | 2485 | |
70a59fde | 2486 | refresh_frequency_limits(policy); |
1da177e4 | 2487 | |
fefa8ff8 | 2488 | unlock: |
540a3758 | 2489 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2490 | } |
2491 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2492 | ||
5a25e3f7 RW |
2493 | /** |
2494 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2495 | * @cpu: CPU to update the policy limits for. | |
2496 | * | |
2497 | * Invoke the driver's ->update_limits callback if present or call | |
2498 | * cpufreq_update_policy() for @cpu. | |
2499 | */ | |
2500 | void cpufreq_update_limits(unsigned int cpu) | |
2501 | { | |
2502 | if (cpufreq_driver->update_limits) | |
2503 | cpufreq_driver->update_limits(cpu); | |
2504 | else | |
2505 | cpufreq_update_policy(cpu); | |
2506 | } | |
2507 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2508 | ||
6f19efc0 LM |
2509 | /********************************************************************* |
2510 | * BOOST * | |
2511 | *********************************************************************/ | |
2512 | static int cpufreq_boost_set_sw(int state) | |
2513 | { | |
6f19efc0 LM |
2514 | struct cpufreq_policy *policy; |
2515 | int ret = -EINVAL; | |
2516 | ||
f963735a | 2517 | for_each_active_policy(policy) { |
f8bfc116 VK |
2518 | if (!policy->freq_table) |
2519 | continue; | |
49f18560 | 2520 | |
f8bfc116 VK |
2521 | ret = cpufreq_frequency_table_cpuinfo(policy, |
2522 | policy->freq_table); | |
2523 | if (ret) { | |
2524 | pr_err("%s: Policy frequency update failed\n", | |
2525 | __func__); | |
2526 | break; | |
6f19efc0 | 2527 | } |
f8bfc116 | 2528 | |
3000ce3c | 2529 | ret = freq_qos_update_request(policy->max_freq_req, policy->max); |
e61a4125 | 2530 | if (ret < 0) |
18c49926 | 2531 | break; |
6f19efc0 LM |
2532 | } |
2533 | ||
2534 | return ret; | |
2535 | } | |
2536 | ||
2537 | int cpufreq_boost_trigger_state(int state) | |
2538 | { | |
2539 | unsigned long flags; | |
2540 | int ret = 0; | |
2541 | ||
2542 | if (cpufreq_driver->boost_enabled == state) | |
2543 | return 0; | |
2544 | ||
2545 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2546 | cpufreq_driver->boost_enabled = state; | |
2547 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2548 | ||
2549 | ret = cpufreq_driver->set_boost(state); | |
2550 | if (ret) { | |
2551 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2552 | cpufreq_driver->boost_enabled = !state; | |
2553 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2554 | ||
e837f9b5 JP |
2555 | pr_err("%s: Cannot %s BOOST\n", |
2556 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2557 | } |
2558 | ||
2559 | return ret; | |
2560 | } | |
2561 | ||
41669da0 | 2562 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2563 | { |
89f98d7e | 2564 | return cpufreq_driver->set_boost; |
6f19efc0 | 2565 | } |
6f19efc0 | 2566 | |
44139ed4 VK |
2567 | static int create_boost_sysfs_file(void) |
2568 | { | |
2569 | int ret; | |
2570 | ||
c82bd444 | 2571 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2572 | if (ret) |
2573 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2574 | __func__); | |
2575 | ||
2576 | return ret; | |
2577 | } | |
2578 | ||
2579 | static void remove_boost_sysfs_file(void) | |
2580 | { | |
2581 | if (cpufreq_boost_supported()) | |
c82bd444 | 2582 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2583 | } |
2584 | ||
2585 | int cpufreq_enable_boost_support(void) | |
2586 | { | |
2587 | if (!cpufreq_driver) | |
2588 | return -EINVAL; | |
2589 | ||
2590 | if (cpufreq_boost_supported()) | |
2591 | return 0; | |
2592 | ||
7a6c79f2 | 2593 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2594 | |
2595 | /* This will get removed on driver unregister */ | |
2596 | return create_boost_sysfs_file(); | |
2597 | } | |
2598 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2599 | ||
6f19efc0 LM |
2600 | int cpufreq_boost_enabled(void) |
2601 | { | |
2602 | return cpufreq_driver->boost_enabled; | |
2603 | } | |
2604 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2605 | ||
1da177e4 LT |
2606 | /********************************************************************* |
2607 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2608 | *********************************************************************/ | |
27622b06 | 2609 | static enum cpuhp_state hp_online; |
1da177e4 | 2610 | |
c4a3fa26 CY |
2611 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2612 | { | |
2613 | cpufreq_online(cpu); | |
2614 | ||
2615 | return 0; | |
2616 | } | |
2617 | ||
2618 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2619 | { | |
2620 | cpufreq_offline(cpu); | |
2621 | ||
2622 | return 0; | |
2623 | } | |
2624 | ||
1da177e4 LT |
2625 | /** |
2626 | * cpufreq_register_driver - register a CPU Frequency driver | |
2627 | * @driver_data: A struct cpufreq_driver containing the values# | |
2628 | * submitted by the CPU Frequency driver. | |
2629 | * | |
bb176f7d | 2630 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2631 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2632 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2633 | * |
2634 | */ | |
221dee28 | 2635 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2636 | { |
2637 | unsigned long flags; | |
2638 | int ret; | |
2639 | ||
a7b422cd KRW |
2640 | if (cpufreq_disabled()) |
2641 | return -ENODEV; | |
2642 | ||
46770be0 VK |
2643 | /* |
2644 | * The cpufreq core depends heavily on the availability of device | |
2645 | * structure, make sure they are available before proceeding further. | |
2646 | */ | |
2647 | if (!get_cpu_device(0)) | |
2648 | return -EPROBE_DEFER; | |
2649 | ||
1da177e4 | 2650 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2651 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2652 | driver_data->target) || |
2653 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2654 | driver_data->target)) || |
a9a22b57 | 2655 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2656 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2657 | return -EINVAL; |
2658 | ||
2d06d8c4 | 2659 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2660 | |
fdd320da | 2661 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2662 | cpus_read_lock(); |
fdd320da | 2663 | |
0d1857a1 | 2664 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2665 | if (cpufreq_driver) { |
0d1857a1 | 2666 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2667 | ret = -EEXIST; |
2668 | goto out; | |
1da177e4 | 2669 | } |
1c3d85dd | 2670 | cpufreq_driver = driver_data; |
0d1857a1 | 2671 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2672 | |
bc68b7df VK |
2673 | if (driver_data->setpolicy) |
2674 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2675 | ||
7a6c79f2 RW |
2676 | if (cpufreq_boost_supported()) { |
2677 | ret = create_boost_sysfs_file(); | |
2678 | if (ret) | |
2679 | goto err_null_driver; | |
2680 | } | |
6f19efc0 | 2681 | |
8a25a2fd | 2682 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2683 | if (ret) |
6f19efc0 | 2684 | goto err_boost_unreg; |
1da177e4 | 2685 | |
ce1bcfe9 VK |
2686 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2687 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2688 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2689 | ret = -ENODEV; |
ce1bcfe9 VK |
2690 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2691 | driver_data->name); | |
2692 | goto err_if_unreg; | |
1da177e4 LT |
2693 | } |
2694 | ||
a92551e4 SAS |
2695 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2696 | "cpufreq:online", | |
2697 | cpuhp_cpufreq_online, | |
2698 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2699 | if (ret < 0) |
2700 | goto err_if_unreg; | |
2701 | hp_online = ret; | |
5372e054 | 2702 | ret = 0; |
27622b06 | 2703 | |
2d06d8c4 | 2704 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2705 | goto out; |
fdd320da | 2706 | |
8a25a2fd KS |
2707 | err_if_unreg: |
2708 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2709 | err_boost_unreg: |
44139ed4 | 2710 | remove_boost_sysfs_file(); |
8f5bc2ab | 2711 | err_null_driver: |
0d1857a1 | 2712 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2713 | cpufreq_driver = NULL; |
0d1857a1 | 2714 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2715 | out: |
a92551e4 | 2716 | cpus_read_unlock(); |
3834abb4 | 2717 | return ret; |
1da177e4 LT |
2718 | } |
2719 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2720 | ||
1da177e4 LT |
2721 | /** |
2722 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2723 | * | |
bb176f7d | 2724 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2725 | * the right to do so, i.e. if you have succeeded in initialising before! |
2726 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2727 | * currently not initialised. | |
2728 | */ | |
221dee28 | 2729 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2730 | { |
2731 | unsigned long flags; | |
2732 | ||
1c3d85dd | 2733 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2734 | return -EINVAL; |
1da177e4 | 2735 | |
2d06d8c4 | 2736 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2737 | |
454d3a25 | 2738 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2739 | cpus_read_lock(); |
8a25a2fd | 2740 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2741 | remove_boost_sysfs_file(); |
a92551e4 | 2742 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2743 | |
0d1857a1 | 2744 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2745 | |
1c3d85dd | 2746 | cpufreq_driver = NULL; |
6eed9404 | 2747 | |
0d1857a1 | 2748 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2749 | cpus_read_unlock(); |
1da177e4 LT |
2750 | |
2751 | return 0; | |
2752 | } | |
2753 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2754 | |
c82bd444 VK |
2755 | struct kobject *cpufreq_global_kobject; |
2756 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2757 | ||
5a01f2e8 VP |
2758 | static int __init cpufreq_core_init(void) |
2759 | { | |
a7b422cd KRW |
2760 | if (cpufreq_disabled()) |
2761 | return -ENODEV; | |
2762 | ||
8eec1020 | 2763 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2764 | BUG_ON(!cpufreq_global_kobject); |
2765 | ||
5a01f2e8 VP |
2766 | return 0; |
2767 | } | |
d82f2692 | 2768 | module_param(off, int, 0444); |
5a01f2e8 | 2769 | core_initcall(cpufreq_core_init); |