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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/drivers/cpufreq/cpufreq.c | |
4 | * | |
5 | * Copyright (C) 2001 Russell King | |
6 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 7 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 8 | * |
c32b6b8e | 9 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 10 | * Added handling for CPU hotplug |
8ff69732 DJ |
11 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
12 | * Fix handling for CPU hotplug -- affected CPUs | |
1da177e4 LT |
13 | */ |
14 | ||
db701151 VK |
15 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
16 | ||
5ff0a268 | 17 | #include <linux/cpu.h> |
1da177e4 | 18 | #include <linux/cpufreq.h> |
5c238a8b | 19 | #include <linux/cpu_cooling.h> |
1da177e4 | 20 | #include <linux/delay.h> |
1da177e4 | 21 | #include <linux/device.h> |
5ff0a268 VK |
22 | #include <linux/init.h> |
23 | #include <linux/kernel_stat.h> | |
24 | #include <linux/module.h> | |
3fc54d37 | 25 | #include <linux/mutex.h> |
67d874c3 | 26 | #include <linux/pm_qos.h> |
5ff0a268 | 27 | #include <linux/slab.h> |
2f0aea93 | 28 | #include <linux/suspend.h> |
90de2a4a | 29 | #include <linux/syscore_ops.h> |
5ff0a268 | 30 | #include <linux/tick.h> |
6f4f2723 TR |
31 | #include <trace/events/power.h> |
32 | ||
b4f0676f | 33 | static LIST_HEAD(cpufreq_policy_list); |
f963735a | 34 | |
f963735a | 35 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
36 | #define for_each_suitable_policy(__policy, __active) \ |
37 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
38 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
39 | |
40 | #define for_each_active_policy(__policy) \ | |
41 | for_each_suitable_policy(__policy, true) | |
42 | #define for_each_inactive_policy(__policy) \ | |
43 | for_each_suitable_policy(__policy, false) | |
44 | ||
45 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
46 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
47 | ||
f7b27061 VK |
48 | /* Iterate over governors */ |
49 | static LIST_HEAD(cpufreq_governor_list); | |
50 | #define for_each_governor(__governor) \ | |
51 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
52 | ||
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); | |
aed8e0a1 RW |
77 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
78 | struct cpufreq_governor *new_gov, | |
79 | unsigned int new_pol); | |
45482c70 | 80 | |
1da177e4 | 81 | /** |
32ee8c3e DJ |
82 | * Two notifier lists: the "policy" list is involved in the |
83 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
84 | * "transition" list for kernel code that needs to handle |
85 | * changes to devices when the CPU clock speed changes. | |
86 | * The mutex locks both lists. | |
87 | */ | |
e041c683 | 88 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
cc85de36 | 89 | SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); |
1da177e4 | 90 | |
a7b422cd | 91 | static int off __read_mostly; |
da584455 | 92 | static int cpufreq_disabled(void) |
a7b422cd KRW |
93 | { |
94 | return off; | |
95 | } | |
96 | void disable_cpufreq(void) | |
97 | { | |
98 | off = 1; | |
99 | } | |
29464f28 | 100 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 101 | |
4d5dcc42 VK |
102 | bool have_governor_per_policy(void) |
103 | { | |
0b981e70 | 104 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 105 | } |
3f869d6d | 106 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 107 | |
944e9a03 VK |
108 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
109 | { | |
110 | if (have_governor_per_policy()) | |
111 | return &policy->kobj; | |
112 | else | |
113 | return cpufreq_global_kobject; | |
114 | } | |
115 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
116 | ||
72a4ce34 VK |
117 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
118 | { | |
119 | u64 idle_time; | |
120 | u64 cur_wall_time; | |
121 | u64 busy_time; | |
122 | ||
7fb1327e | 123 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 VK |
124 | |
125 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
126 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
127 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
128 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
129 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
130 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
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 | ||
6193079b VK |
619 | static struct cpufreq_governor *get_governor(const char *str_governor) |
620 | { | |
621 | struct cpufreq_governor *t; | |
622 | ||
623 | mutex_lock(&cpufreq_governor_mutex); | |
624 | t = find_governor(str_governor); | |
625 | if (!t) | |
626 | goto unlock; | |
627 | ||
628 | if (!try_module_get(t->owner)) | |
629 | t = NULL; | |
630 | ||
631 | unlock: | |
632 | mutex_unlock(&cpufreq_governor_mutex); | |
633 | ||
634 | return t; | |
635 | } | |
636 | ||
aed8e0a1 | 637 | static unsigned int cpufreq_parse_policy(char *str_governor) |
ab05d97a | 638 | { |
aed8e0a1 RW |
639 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) |
640 | return CPUFREQ_POLICY_PERFORMANCE; | |
641 | ||
642 | if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) | |
643 | return CPUFREQ_POLICY_POWERSAVE; | |
644 | ||
645 | return CPUFREQ_POLICY_UNKNOWN; | |
ab05d97a YH |
646 | } |
647 | ||
1da177e4 | 648 | /** |
5ddc6d4e | 649 | * cpufreq_parse_governor - parse a governor string only for has_target() |
aed8e0a1 | 650 | * @str_governor: Governor name. |
1da177e4 | 651 | */ |
aed8e0a1 | 652 | static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor) |
1da177e4 | 653 | { |
ab05d97a | 654 | struct cpufreq_governor *t; |
045149e6 | 655 | |
6193079b VK |
656 | t = get_governor(str_governor); |
657 | if (t) | |
658 | return t; | |
ea714970 | 659 | |
6193079b VK |
660 | if (request_module("cpufreq_%s", str_governor)) |
661 | return NULL; | |
045149e6 | 662 | |
6193079b | 663 | return get_governor(str_governor); |
1da177e4 | 664 | } |
1da177e4 | 665 | |
1da177e4 | 666 | /** |
e08f5f5b GS |
667 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
668 | * print out cpufreq information | |
1da177e4 LT |
669 | * |
670 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
671 | * "unsigned int". | |
672 | */ | |
673 | ||
32ee8c3e DJ |
674 | #define show_one(file_name, object) \ |
675 | static ssize_t show_##file_name \ | |
905d77cd | 676 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 677 | { \ |
29464f28 | 678 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
679 | } |
680 | ||
681 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
682 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 683 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
684 | show_one(scaling_min_freq, min); |
685 | show_one(scaling_max_freq, max); | |
c034b02e | 686 | |
f8475cef LB |
687 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
688 | { | |
689 | return 0; | |
690 | } | |
691 | ||
09347b29 | 692 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
693 | { |
694 | ssize_t ret; | |
f8475cef | 695 | unsigned int freq; |
c034b02e | 696 | |
f8475cef LB |
697 | freq = arch_freq_get_on_cpu(policy->cpu); |
698 | if (freq) | |
699 | ret = sprintf(buf, "%u\n", freq); | |
700 | else if (cpufreq_driver && cpufreq_driver->setpolicy && | |
701 | cpufreq_driver->get) | |
c034b02e DB |
702 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
703 | else | |
704 | ret = sprintf(buf, "%u\n", policy->cur); | |
705 | return ret; | |
706 | } | |
1da177e4 LT |
707 | |
708 | /** | |
709 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
710 | */ | |
711 | #define store_one(file_name, object) \ | |
712 | static ssize_t store_##file_name \ | |
905d77cd | 713 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 714 | { \ |
18c49926 VK |
715 | unsigned long val; \ |
716 | int ret; \ | |
1da177e4 | 717 | \ |
18c49926 | 718 | ret = sscanf(buf, "%lu", &val); \ |
1da177e4 LT |
719 | if (ret != 1) \ |
720 | return -EINVAL; \ | |
721 | \ | |
3000ce3c | 722 | ret = freq_qos_update_request(policy->object##_freq_req, val);\ |
18c49926 | 723 | return ret >= 0 ? count : ret; \ |
1da177e4 LT |
724 | } |
725 | ||
29464f28 DJ |
726 | store_one(scaling_min_freq, min); |
727 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
728 | |
729 | /** | |
730 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
731 | */ | |
905d77cd DJ |
732 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
733 | char *buf) | |
1da177e4 | 734 | { |
d92d50a4 | 735 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
736 | |
737 | if (cur_freq) | |
738 | return sprintf(buf, "%u\n", cur_freq); | |
739 | ||
740 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
741 | } |
742 | ||
1da177e4 LT |
743 | /** |
744 | * show_scaling_governor - show the current policy for the specified CPU | |
745 | */ | |
905d77cd | 746 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 747 | { |
29464f28 | 748 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
749 | return sprintf(buf, "powersave\n"); |
750 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
751 | return sprintf(buf, "performance\n"); | |
752 | else if (policy->governor) | |
4b972f0b | 753 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 754 | policy->governor->name); |
1da177e4 LT |
755 | return -EINVAL; |
756 | } | |
757 | ||
1da177e4 LT |
758 | /** |
759 | * store_scaling_governor - store policy for the specified CPU | |
760 | */ | |
905d77cd DJ |
761 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
762 | const char *buf, size_t count) | |
1da177e4 | 763 | { |
aed8e0a1 | 764 | char str_governor[16]; |
5136fa56 | 765 | int ret; |
1da177e4 | 766 | |
29464f28 | 767 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
768 | if (ret != 1) |
769 | return -EINVAL; | |
770 | ||
ab05d97a | 771 | if (cpufreq_driver->setpolicy) { |
aed8e0a1 RW |
772 | unsigned int new_pol; |
773 | ||
774 | new_pol = cpufreq_parse_policy(str_governor); | |
775 | if (!new_pol) | |
ab05d97a | 776 | return -EINVAL; |
aed8e0a1 RW |
777 | |
778 | ret = cpufreq_set_policy(policy, NULL, new_pol); | |
ab05d97a | 779 | } else { |
aed8e0a1 RW |
780 | struct cpufreq_governor *new_gov; |
781 | ||
782 | new_gov = cpufreq_parse_governor(str_governor); | |
783 | if (!new_gov) | |
ab05d97a | 784 | return -EINVAL; |
1da177e4 | 785 | |
aed8e0a1 RW |
786 | ret = cpufreq_set_policy(policy, new_gov, |
787 | CPUFREQ_POLICY_UNKNOWN); | |
a8b149d3 | 788 | |
aed8e0a1 RW |
789 | module_put(new_gov->owner); |
790 | } | |
a8b149d3 | 791 | |
88dc4384 | 792 | return ret ? ret : count; |
1da177e4 LT |
793 | } |
794 | ||
795 | /** | |
796 | * show_scaling_driver - show the cpufreq driver currently loaded | |
797 | */ | |
905d77cd | 798 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 799 | { |
1c3d85dd | 800 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
801 | } |
802 | ||
803 | /** | |
804 | * show_scaling_available_governors - show the available CPUfreq governors | |
805 | */ | |
905d77cd DJ |
806 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
807 | char *buf) | |
1da177e4 LT |
808 | { |
809 | ssize_t i = 0; | |
810 | struct cpufreq_governor *t; | |
811 | ||
9c0ebcf7 | 812 | if (!has_target()) { |
1da177e4 LT |
813 | i += sprintf(buf, "performance powersave"); |
814 | goto out; | |
815 | } | |
816 | ||
6193079b | 817 | mutex_lock(&cpufreq_governor_mutex); |
f7b27061 | 818 | for_each_governor(t) { |
29464f28 DJ |
819 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
820 | - (CPUFREQ_NAME_LEN + 2))) | |
6193079b | 821 | break; |
4b972f0b | 822 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 823 | } |
6193079b | 824 | mutex_unlock(&cpufreq_governor_mutex); |
7d5e350f | 825 | out: |
1da177e4 LT |
826 | i += sprintf(&buf[i], "\n"); |
827 | return i; | |
828 | } | |
e8628dd0 | 829 | |
f4fd3797 | 830 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
831 | { |
832 | ssize_t i = 0; | |
833 | unsigned int cpu; | |
834 | ||
835481d9 | 835 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
836 | if (i) |
837 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
838 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
839 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 840 | break; |
1da177e4 LT |
841 | } |
842 | i += sprintf(&buf[i], "\n"); | |
843 | return i; | |
844 | } | |
f4fd3797 | 845 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 846 | |
e8628dd0 DW |
847 | /** |
848 | * show_related_cpus - show the CPUs affected by each transition even if | |
849 | * hw coordination is in use | |
850 | */ | |
851 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
852 | { | |
f4fd3797 | 853 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
854 | } |
855 | ||
856 | /** | |
857 | * show_affected_cpus - show the CPUs affected by each transition | |
858 | */ | |
859 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
860 | { | |
f4fd3797 | 861 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
862 | } |
863 | ||
9e76988e | 864 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 865 | const char *buf, size_t count) |
9e76988e VP |
866 | { |
867 | unsigned int freq = 0; | |
868 | unsigned int ret; | |
869 | ||
879000f9 | 870 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
871 | return -EINVAL; |
872 | ||
873 | ret = sscanf(buf, "%u", &freq); | |
874 | if (ret != 1) | |
875 | return -EINVAL; | |
876 | ||
877 | policy->governor->store_setspeed(policy, freq); | |
878 | ||
879 | return count; | |
880 | } | |
881 | ||
882 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
883 | { | |
879000f9 | 884 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
885 | return sprintf(buf, "<unsupported>\n"); |
886 | ||
887 | return policy->governor->show_setspeed(policy, buf); | |
888 | } | |
1da177e4 | 889 | |
e2f74f35 | 890 | /** |
8bf1ac72 | 891 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
892 | */ |
893 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
894 | { | |
895 | unsigned int limit; | |
896 | int ret; | |
b23aa311 YH |
897 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); |
898 | if (!ret) | |
899 | return sprintf(buf, "%u\n", limit); | |
e2f74f35 TR |
900 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); |
901 | } | |
902 | ||
6dad2a29 BP |
903 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
904 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
905 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
906 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
907 | cpufreq_freq_attr_ro(scaling_available_governors); | |
908 | cpufreq_freq_attr_ro(scaling_driver); | |
909 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
910 | cpufreq_freq_attr_ro(bios_limit); | |
911 | cpufreq_freq_attr_ro(related_cpus); | |
912 | cpufreq_freq_attr_ro(affected_cpus); | |
913 | cpufreq_freq_attr_rw(scaling_min_freq); | |
914 | cpufreq_freq_attr_rw(scaling_max_freq); | |
915 | cpufreq_freq_attr_rw(scaling_governor); | |
916 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 917 | |
905d77cd | 918 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
919 | &cpuinfo_min_freq.attr, |
920 | &cpuinfo_max_freq.attr, | |
ed129784 | 921 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
922 | &scaling_min_freq.attr, |
923 | &scaling_max_freq.attr, | |
924 | &affected_cpus.attr, | |
e8628dd0 | 925 | &related_cpus.attr, |
1da177e4 LT |
926 | &scaling_governor.attr, |
927 | &scaling_driver.attr, | |
928 | &scaling_available_governors.attr, | |
9e76988e | 929 | &scaling_setspeed.attr, |
1da177e4 LT |
930 | NULL |
931 | }; | |
932 | ||
29464f28 DJ |
933 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
934 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 935 | |
29464f28 | 936 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 937 | { |
905d77cd DJ |
938 | struct cpufreq_policy *policy = to_policy(kobj); |
939 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 940 | ssize_t ret; |
6eed9404 | 941 | |
4d95fc25 KS |
942 | if (!fattr->show) |
943 | return -EIO; | |
944 | ||
ad7722da | 945 | down_read(&policy->rwsem); |
6541aef0 | 946 | ret = fattr->show(policy, buf); |
ad7722da | 947 | up_read(&policy->rwsem); |
1b750e3b | 948 | |
1da177e4 LT |
949 | return ret; |
950 | } | |
951 | ||
905d77cd DJ |
952 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
953 | const char *buf, size_t count) | |
1da177e4 | 954 | { |
905d77cd DJ |
955 | struct cpufreq_policy *policy = to_policy(kobj); |
956 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 957 | ssize_t ret = -EINVAL; |
6eed9404 | 958 | |
4d95fc25 KS |
959 | if (!fattr->store) |
960 | return -EIO; | |
961 | ||
9b3d9bb3 WL |
962 | /* |
963 | * cpus_read_trylock() is used here to work around a circular lock | |
964 | * dependency problem with respect to the cpufreq_register_driver(). | |
965 | */ | |
966 | if (!cpus_read_trylock()) | |
967 | return -EBUSY; | |
4f750c93 | 968 | |
6541aef0 RW |
969 | if (cpu_online(policy->cpu)) { |
970 | down_write(&policy->rwsem); | |
e08f5f5b | 971 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
972 | up_write(&policy->rwsem); |
973 | } | |
e08f5f5b | 974 | |
a92551e4 | 975 | cpus_read_unlock(); |
4f750c93 | 976 | |
1da177e4 LT |
977 | return ret; |
978 | } | |
979 | ||
905d77cd | 980 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 981 | { |
905d77cd | 982 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 983 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
984 | complete(&policy->kobj_unregister); |
985 | } | |
986 | ||
52cf25d0 | 987 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
988 | .show = show, |
989 | .store = store, | |
990 | }; | |
991 | ||
992 | static struct kobj_type ktype_cpufreq = { | |
993 | .sysfs_ops = &sysfs_ops, | |
994 | .default_attrs = default_attrs, | |
995 | .release = cpufreq_sysfs_release, | |
996 | }; | |
997 | ||
2f0ba790 | 998 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) |
87549141 | 999 | { |
2f0ba790 RW |
1000 | struct device *dev = get_cpu_device(cpu); |
1001 | ||
67d874c3 | 1002 | if (unlikely(!dev)) |
2f0ba790 RW |
1003 | return; |
1004 | ||
1005 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
1006 | return; | |
1007 | ||
26619804 | 1008 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
1009 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
1010 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
1011 | } |
1012 | ||
26619804 VK |
1013 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
1014 | struct device *dev) | |
87549141 | 1015 | { |
26619804 VK |
1016 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
1017 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
1018 | } |
1019 | ||
d9612a49 | 1020 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
1021 | { |
1022 | struct freq_attr **drv_attr; | |
909a694e | 1023 | int ret = 0; |
909a694e | 1024 | |
909a694e | 1025 | /* set up files for this cpu device */ |
1c3d85dd | 1026 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1027 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1028 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1029 | if (ret) | |
6d4e81ed | 1030 | return ret; |
909a694e DJ |
1031 | drv_attr++; |
1032 | } | |
1c3d85dd | 1033 | if (cpufreq_driver->get) { |
909a694e DJ |
1034 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1035 | if (ret) | |
6d4e81ed | 1036 | return ret; |
909a694e | 1037 | } |
c034b02e DB |
1038 | |
1039 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1040 | if (ret) | |
6d4e81ed | 1041 | return ret; |
c034b02e | 1042 | |
1c3d85dd | 1043 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1044 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1045 | if (ret) | |
6d4e81ed | 1046 | return ret; |
e2f74f35 | 1047 | } |
909a694e | 1048 | |
26619804 | 1049 | return 0; |
e18f1682 SB |
1050 | } |
1051 | ||
de1df26b RW |
1052 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
1053 | { | |
1054 | return NULL; | |
1055 | } | |
1056 | ||
7f0fa40f | 1057 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1058 | { |
aed8e0a1 RW |
1059 | struct cpufreq_governor *def_gov = cpufreq_default_governor(); |
1060 | struct cpufreq_governor *gov = NULL; | |
1061 | unsigned int pol = CPUFREQ_POLICY_UNKNOWN; | |
6193079b | 1062 | int ret; |
ab05d97a YH |
1063 | |
1064 | if (has_target()) { | |
aed8e0a1 | 1065 | /* Update policy governor to the one used before hotplug. */ |
6193079b | 1066 | gov = get_governor(policy->last_governor); |
ab05d97a YH |
1067 | if (gov) { |
1068 | pr_debug("Restoring governor %s for cpu %d\n", | |
aed8e0a1 RW |
1069 | policy->governor->name, policy->cpu); |
1070 | } else if (def_gov) { | |
ab05d97a | 1071 | gov = def_gov; |
6193079b | 1072 | __module_get(gov->owner); |
aed8e0a1 RW |
1073 | } else { |
1074 | return -ENODATA; | |
ab05d97a | 1075 | } |
de1df26b | 1076 | } else { |
ab05d97a YH |
1077 | /* Use the default policy if there is no last_policy. */ |
1078 | if (policy->last_policy) { | |
aed8e0a1 RW |
1079 | pol = policy->last_policy; |
1080 | } else if (def_gov) { | |
1081 | pol = cpufreq_parse_policy(def_gov->name); | |
a28af18d RW |
1082 | /* |
1083 | * In case the default governor is neiter "performance" | |
1084 | * nor "powersave", fall back to the initial policy | |
1085 | * value set by the driver. | |
1086 | */ | |
1087 | if (pol == CPUFREQ_POLICY_UNKNOWN) | |
1088 | pol = policy->policy; | |
ab05d97a | 1089 | } |
a28af18d RW |
1090 | if (pol != CPUFREQ_POLICY_PERFORMANCE && |
1091 | pol != CPUFREQ_POLICY_POWERSAVE) | |
1092 | return -ENODATA; | |
69030dd1 | 1093 | } |
ab05d97a | 1094 | |
6193079b VK |
1095 | ret = cpufreq_set_policy(policy, gov, pol); |
1096 | if (gov) | |
1097 | module_put(gov->owner); | |
1098 | ||
1099 | return ret; | |
909a694e DJ |
1100 | } |
1101 | ||
d9612a49 | 1102 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1103 | { |
9c0ebcf7 | 1104 | int ret = 0; |
fcf80582 | 1105 | |
bb29ae15 VK |
1106 | /* Has this CPU been taken care of already? */ |
1107 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1108 | return 0; | |
1109 | ||
49f18560 | 1110 | down_write(&policy->rwsem); |
45482c70 RW |
1111 | if (has_target()) |
1112 | cpufreq_stop_governor(policy); | |
fcf80582 | 1113 | |
fcf80582 | 1114 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1115 | |
9c0ebcf7 | 1116 | if (has_target()) { |
0a300767 | 1117 | ret = cpufreq_start_governor(policy); |
49f18560 | 1118 | if (ret) |
3de9bdeb | 1119 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1120 | } |
49f18560 VK |
1121 | up_write(&policy->rwsem); |
1122 | return ret; | |
fcf80582 | 1123 | } |
1da177e4 | 1124 | |
c57b25bd | 1125 | void refresh_frequency_limits(struct cpufreq_policy *policy) |
70a59fde | 1126 | { |
67d874c3 | 1127 | if (!policy_is_inactive(policy)) { |
67d874c3 | 1128 | pr_debug("updating policy for CPU %u\n", policy->cpu); |
70a59fde | 1129 | |
aed8e0a1 | 1130 | cpufreq_set_policy(policy, policy->governor, policy->policy); |
67d874c3 | 1131 | } |
70a59fde | 1132 | } |
c57b25bd | 1133 | EXPORT_SYMBOL(refresh_frequency_limits); |
70a59fde | 1134 | |
11eb69b9 VK |
1135 | static void handle_update(struct work_struct *work) |
1136 | { | |
1137 | struct cpufreq_policy *policy = | |
1138 | container_of(work, struct cpufreq_policy, update); | |
70a59fde VK |
1139 | |
1140 | pr_debug("handle_update for cpu %u called\n", policy->cpu); | |
67d874c3 | 1141 | down_write(&policy->rwsem); |
70a59fde | 1142 | refresh_frequency_limits(policy); |
67d874c3 VK |
1143 | up_write(&policy->rwsem); |
1144 | } | |
1145 | ||
1146 | static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq, | |
1147 | void *data) | |
1148 | { | |
1149 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min); | |
1150 | ||
1151 | schedule_work(&policy->update); | |
1152 | return 0; | |
1153 | } | |
1154 | ||
1155 | static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq, | |
1156 | void *data) | |
1157 | { | |
1158 | struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max); | |
1159 | ||
1160 | schedule_work(&policy->update); | |
1161 | return 0; | |
1162 | } | |
1163 | ||
1164 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) | |
1165 | { | |
1166 | struct kobject *kobj; | |
1167 | struct completion *cmp; | |
1168 | ||
1169 | down_write(&policy->rwsem); | |
1170 | cpufreq_stats_free_table(policy); | |
1171 | kobj = &policy->kobj; | |
1172 | cmp = &policy->kobj_unregister; | |
1173 | up_write(&policy->rwsem); | |
1174 | kobject_put(kobj); | |
1175 | ||
1176 | /* | |
1177 | * We need to make sure that the underlying kobj is | |
1178 | * actually not referenced anymore by anybody before we | |
1179 | * proceed with unloading. | |
1180 | */ | |
1181 | pr_debug("waiting for dropping of refcount\n"); | |
1182 | wait_for_completion(cmp); | |
1183 | pr_debug("wait complete\n"); | |
fcf80582 | 1184 | } |
1da177e4 | 1185 | |
a34e63b1 | 1186 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1187 | { |
1188 | struct cpufreq_policy *policy; | |
67d874c3 | 1189 | struct device *dev = get_cpu_device(cpu); |
edd4a893 | 1190 | int ret; |
e9698cc5 | 1191 | |
67d874c3 VK |
1192 | if (!dev) |
1193 | return NULL; | |
1194 | ||
e9698cc5 SB |
1195 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1196 | if (!policy) | |
1197 | return NULL; | |
1198 | ||
1199 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1200 | goto err_free_policy; | |
1201 | ||
1202 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1203 | goto err_free_cpumask; | |
1204 | ||
559ed407 RW |
1205 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1206 | goto err_free_rcpumask; | |
1207 | ||
edd4a893 VK |
1208 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1209 | cpufreq_global_kobject, "policy%u", cpu); | |
1210 | if (ret) { | |
67d874c3 | 1211 | dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret); |
2acb9bda RW |
1212 | /* |
1213 | * The entire policy object will be freed below, but the extra | |
1214 | * memory allocated for the kobject name needs to be freed by | |
1215 | * releasing the kobject. | |
1216 | */ | |
4ebe36c9 | 1217 | kobject_put(&policy->kobj); |
edd4a893 VK |
1218 | goto err_free_real_cpus; |
1219 | } | |
1220 | ||
3000ce3c RW |
1221 | freq_constraints_init(&policy->constraints); |
1222 | ||
67d874c3 VK |
1223 | policy->nb_min.notifier_call = cpufreq_notifier_min; |
1224 | policy->nb_max.notifier_call = cpufreq_notifier_max; | |
1225 | ||
3000ce3c RW |
1226 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MIN, |
1227 | &policy->nb_min); | |
67d874c3 VK |
1228 | if (ret) { |
1229 | dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n", | |
1230 | ret, cpumask_pr_args(policy->cpus)); | |
1231 | goto err_kobj_remove; | |
1232 | } | |
1233 | ||
3000ce3c RW |
1234 | ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MAX, |
1235 | &policy->nb_max); | |
67d874c3 VK |
1236 | if (ret) { |
1237 | dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n", | |
1238 | ret, cpumask_pr_args(policy->cpus)); | |
1239 | goto err_min_qos_notifier; | |
1240 | } | |
1241 | ||
c88a1f8b | 1242 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1243 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1244 | spin_lock_init(&policy->transition_lock); |
1245 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1246 | init_completion(&policy->kobj_unregister); |
1247 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1248 | |
a34e63b1 | 1249 | policy->cpu = cpu; |
e9698cc5 SB |
1250 | return policy; |
1251 | ||
67d874c3 | 1252 | err_min_qos_notifier: |
3000ce3c RW |
1253 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, |
1254 | &policy->nb_min); | |
67d874c3 VK |
1255 | err_kobj_remove: |
1256 | cpufreq_policy_put_kobj(policy); | |
edd4a893 VK |
1257 | err_free_real_cpus: |
1258 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1259 | err_free_rcpumask: |
1260 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1261 | err_free_cpumask: |
1262 | free_cpumask_var(policy->cpus); | |
1263 | err_free_policy: | |
1264 | kfree(policy); | |
1265 | ||
1266 | return NULL; | |
1267 | } | |
1268 | ||
f9f41e3e | 1269 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1270 | { |
988bed09 VK |
1271 | unsigned long flags; |
1272 | int cpu; | |
1273 | ||
1274 | /* Remove policy from list */ | |
1275 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1276 | list_del(&policy->policy_list); | |
1277 | ||
1278 | for_each_cpu(cpu, policy->related_cpus) | |
1279 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1280 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1281 | ||
3000ce3c RW |
1282 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MAX, |
1283 | &policy->nb_max); | |
1284 | freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN, | |
1285 | &policy->nb_min); | |
6a149036 | 1286 | |
6941051d SH |
1287 | /* Cancel any pending policy->update work before freeing the policy. */ |
1288 | cancel_work_sync(&policy->update); | |
1289 | ||
6a149036 VK |
1290 | if (policy->max_freq_req) { |
1291 | /* | |
1292 | * CPUFREQ_CREATE_POLICY notification is sent only after | |
1293 | * successfully adding max_freq_req request. | |
1294 | */ | |
1295 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1296 | CPUFREQ_REMOVE_POLICY, policy); | |
3000ce3c | 1297 | freq_qos_remove_request(policy->max_freq_req); |
6a149036 VK |
1298 | } |
1299 | ||
3000ce3c | 1300 | freq_qos_remove_request(policy->min_freq_req); |
18c49926 | 1301 | kfree(policy->min_freq_req); |
67d874c3 | 1302 | |
f9f41e3e | 1303 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1304 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1305 | free_cpumask_var(policy->related_cpus); |
1306 | free_cpumask_var(policy->cpus); | |
1307 | kfree(policy); | |
1308 | } | |
1309 | ||
0b275352 | 1310 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1311 | { |
7f0c020a | 1312 | struct cpufreq_policy *policy; |
194d99c7 | 1313 | bool new_policy; |
1da177e4 | 1314 | unsigned long flags; |
0b275352 RW |
1315 | unsigned int j; |
1316 | int ret; | |
87549141 | 1317 | |
0b275352 | 1318 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1319 | |
bb29ae15 | 1320 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1321 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1322 | if (policy) { |
9104bb26 | 1323 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1324 | if (!policy_is_inactive(policy)) |
d9612a49 | 1325 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1326 | |
11ce707e | 1327 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1328 | new_policy = false; |
11ce707e RW |
1329 | down_write(&policy->rwsem); |
1330 | policy->cpu = cpu; | |
1331 | policy->governor = NULL; | |
1332 | up_write(&policy->rwsem); | |
1333 | } else { | |
194d99c7 | 1334 | new_policy = true; |
a34e63b1 | 1335 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1336 | if (!policy) |
d4d854d6 | 1337 | return -ENOMEM; |
72368d12 | 1338 | } |
0d66b91e | 1339 | |
91a12e91 VK |
1340 | if (!new_policy && cpufreq_driver->online) { |
1341 | ret = cpufreq_driver->online(policy); | |
1342 | if (ret) { | |
1343 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1344 | __LINE__); | |
1345 | goto out_exit_policy; | |
1346 | } | |
1da177e4 | 1347 | |
91a12e91 VK |
1348 | /* Recover policy->cpus using related_cpus */ |
1349 | cpumask_copy(policy->cpus, policy->related_cpus); | |
1350 | } else { | |
1351 | cpumask_copy(policy->cpus, cpumask_of(cpu)); | |
643ae6e8 | 1352 | |
91a12e91 VK |
1353 | /* |
1354 | * Call driver. From then on the cpufreq must be able | |
1355 | * to accept all calls to ->verify and ->setpolicy for this CPU. | |
1356 | */ | |
1357 | ret = cpufreq_driver->init(policy); | |
1358 | if (ret) { | |
1359 | pr_debug("%s: %d: initialization failed\n", __func__, | |
1360 | __LINE__); | |
1361 | goto out_free_policy; | |
1362 | } | |
d417e069 | 1363 | |
91a12e91 VK |
1364 | ret = cpufreq_table_validate_and_sort(policy); |
1365 | if (ret) | |
1366 | goto out_exit_policy; | |
6d4e81ed | 1367 | |
4d1f3a5b | 1368 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1369 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1370 | } |
559ed407 | 1371 | |
91a12e91 | 1372 | down_write(&policy->rwsem); |
5a7e56a5 VK |
1373 | /* |
1374 | * affected cpus must always be the one, which are online. We aren't | |
1375 | * managing offline cpus here. | |
1376 | */ | |
1377 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1378 | ||
194d99c7 | 1379 | if (new_policy) { |
2f0ba790 | 1380 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1381 | per_cpu(cpufreq_cpu_data, j) = policy; |
2f0ba790 RW |
1382 | add_cpu_dev_symlink(policy, j); |
1383 | } | |
18c49926 VK |
1384 | |
1385 | policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), | |
1386 | GFP_KERNEL); | |
1387 | if (!policy->min_freq_req) | |
1388 | goto out_destroy_policy; | |
1389 | ||
3000ce3c RW |
1390 | ret = freq_qos_add_request(&policy->constraints, |
1391 | policy->min_freq_req, FREQ_QOS_MIN, | |
1392 | policy->min); | |
18c49926 VK |
1393 | if (ret < 0) { |
1394 | /* | |
3000ce3c | 1395 | * So we don't call freq_qos_remove_request() for an |
18c49926 VK |
1396 | * uninitialized request. |
1397 | */ | |
1398 | kfree(policy->min_freq_req); | |
1399 | policy->min_freq_req = NULL; | |
18c49926 VK |
1400 | goto out_destroy_policy; |
1401 | } | |
1402 | ||
1403 | /* | |
1404 | * This must be initialized right here to avoid calling | |
3000ce3c | 1405 | * freq_qos_remove_request() on uninitialized request in case |
18c49926 VK |
1406 | * of errors. |
1407 | */ | |
1408 | policy->max_freq_req = policy->min_freq_req + 1; | |
1409 | ||
3000ce3c RW |
1410 | ret = freq_qos_add_request(&policy->constraints, |
1411 | policy->max_freq_req, FREQ_QOS_MAX, | |
1412 | policy->max); | |
18c49926 VK |
1413 | if (ret < 0) { |
1414 | policy->max_freq_req = NULL; | |
18c49926 VK |
1415 | goto out_destroy_policy; |
1416 | } | |
6a149036 VK |
1417 | |
1418 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1419 | CPUFREQ_CREATE_POLICY, policy); | |
988bed09 | 1420 | } |
652ed95d | 1421 | |
5ddc6d4e | 1422 | if (cpufreq_driver->get && has_target()) { |
da60ce9f VK |
1423 | policy->cur = cpufreq_driver->get(policy->cpu); |
1424 | if (!policy->cur) { | |
1425 | pr_err("%s: ->get() failed\n", __func__); | |
d417e069 | 1426 | goto out_destroy_policy; |
da60ce9f VK |
1427 | } |
1428 | } | |
1429 | ||
d3916691 VK |
1430 | /* |
1431 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1432 | * frequency table present with cpufreq core. In such cases CPU might be | |
1433 | * unstable if it has to run on that frequency for long duration of time | |
1434 | * and so its better to set it to a frequency which is specified in | |
1435 | * freq-table. This also makes cpufreq stats inconsistent as | |
1436 | * cpufreq-stats would fail to register because current frequency of CPU | |
1437 | * isn't found in freq-table. | |
1438 | * | |
1439 | * Because we don't want this change to effect boot process badly, we go | |
1440 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1441 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1442 | * is initialized to zero). | |
1443 | * | |
1444 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1445 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1446 | * equal to target-freq. | |
1447 | */ | |
1448 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1449 | && has_target()) { | |
1450 | /* Are we running at unknown frequency ? */ | |
1451 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1452 | if (ret == -EINVAL) { | |
1453 | /* Warn user and fix it */ | |
1454 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1455 | __func__, policy->cpu, policy->cur); | |
1456 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1457 | CPUFREQ_RELATION_L); | |
1458 | ||
1459 | /* | |
1460 | * Reaching here after boot in a few seconds may not | |
1461 | * mean that system will remain stable at "unknown" | |
1462 | * frequency for longer duration. Hence, a BUG_ON(). | |
1463 | */ | |
1464 | BUG_ON(ret); | |
1465 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1466 | __func__, policy->cpu, policy->cur); | |
1467 | } | |
1468 | } | |
1469 | ||
194d99c7 | 1470 | if (new_policy) { |
d9612a49 | 1471 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1472 | if (ret) |
d417e069 | 1473 | goto out_destroy_policy; |
1aefc75b RW |
1474 | |
1475 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1476 | |
988bed09 VK |
1477 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1478 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1479 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1480 | } | |
9515f4d6 | 1481 | |
7f0fa40f VK |
1482 | ret = cpufreq_init_policy(policy); |
1483 | if (ret) { | |
1484 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1485 | __func__, cpu, ret); | |
d417e069 | 1486 | goto out_destroy_policy; |
08fd8c1c | 1487 | } |
e18f1682 | 1488 | |
4e97b631 | 1489 | up_write(&policy->rwsem); |
08fd8c1c | 1490 | |
038c5b3e | 1491 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1492 | |
7c45cf31 VK |
1493 | /* Callback for handling stuff after policy is ready */ |
1494 | if (cpufreq_driver->ready) | |
1495 | cpufreq_driver->ready(policy); | |
1496 | ||
bcc61569 | 1497 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) |
5c238a8b AK |
1498 | policy->cdev = of_cpufreq_cooling_register(policy); |
1499 | ||
2d06d8c4 | 1500 | pr_debug("initialization complete\n"); |
87c32271 | 1501 | |
1da177e4 LT |
1502 | return 0; |
1503 | ||
d417e069 | 1504 | out_destroy_policy: |
b24b6478 VK |
1505 | for_each_cpu(j, policy->real_cpus) |
1506 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1507 | ||
7106e02b PB |
1508 | up_write(&policy->rwsem); |
1509 | ||
d417e069 | 1510 | out_exit_policy: |
da60ce9f VK |
1511 | if (cpufreq_driver->exit) |
1512 | cpufreq_driver->exit(policy); | |
2f0ba790 | 1513 | |
8101f997 | 1514 | out_free_policy: |
f9f41e3e | 1515 | cpufreq_policy_free(policy); |
1da177e4 LT |
1516 | return ret; |
1517 | } | |
1518 | ||
0b275352 RW |
1519 | /** |
1520 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1521 | * @dev: CPU device. | |
1522 | * @sif: Subsystem interface structure pointer (not used) | |
1523 | */ | |
1524 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1525 | { | |
a794d613 | 1526 | struct cpufreq_policy *policy; |
0b275352 | 1527 | unsigned cpu = dev->id; |
26619804 | 1528 | int ret; |
0b275352 RW |
1529 | |
1530 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1531 | ||
26619804 VK |
1532 | if (cpu_online(cpu)) { |
1533 | ret = cpufreq_online(cpu); | |
1534 | if (ret) | |
1535 | return ret; | |
1536 | } | |
0b275352 | 1537 | |
26619804 | 1538 | /* Create sysfs link on CPU registration */ |
a794d613 | 1539 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 RW |
1540 | if (policy) |
1541 | add_cpu_dev_symlink(policy, cpu); | |
26619804 | 1542 | |
2f0ba790 | 1543 | return 0; |
1da177e4 LT |
1544 | } |
1545 | ||
27622b06 | 1546 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1547 | { |
3a3e9e06 | 1548 | struct cpufreq_policy *policy; |
69cee714 | 1549 | int ret; |
1da177e4 | 1550 | |
b8eed8af | 1551 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1552 | |
988bed09 | 1553 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1554 | if (!policy) { |
b8eed8af | 1555 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1556 | return 0; |
1da177e4 | 1557 | } |
1da177e4 | 1558 | |
49f18560 | 1559 | down_write(&policy->rwsem); |
45482c70 RW |
1560 | if (has_target()) |
1561 | cpufreq_stop_governor(policy); | |
1da177e4 | 1562 | |
9591becb | 1563 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1564 | |
9591becb VK |
1565 | if (policy_is_inactive(policy)) { |
1566 | if (has_target()) | |
1567 | strncpy(policy->last_governor, policy->governor->name, | |
1568 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1569 | else |
1570 | policy->last_policy = policy->policy; | |
9591becb VK |
1571 | } else if (cpu == policy->cpu) { |
1572 | /* Nominate new CPU */ | |
1573 | policy->cpu = cpumask_any(policy->cpus); | |
1574 | } | |
084f3493 | 1575 | |
9591becb VK |
1576 | /* Start governor again for active policy */ |
1577 | if (!policy_is_inactive(policy)) { | |
1578 | if (has_target()) { | |
0a300767 | 1579 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1580 | if (ret) |
1581 | pr_err("%s: Failed to start governor\n", __func__); | |
1582 | } | |
cedb70af | 1583 | |
49f18560 | 1584 | goto unlock; |
cedb70af SB |
1585 | } |
1586 | ||
bcc61569 | 1587 | if (cpufreq_thermal_control_enabled(cpufreq_driver)) { |
5c238a8b AK |
1588 | cpufreq_cooling_unregister(policy->cdev); |
1589 | policy->cdev = NULL; | |
1590 | } | |
1591 | ||
69cee714 VK |
1592 | if (cpufreq_driver->stop_cpu) |
1593 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1594 | |
36be3418 RW |
1595 | if (has_target()) |
1596 | cpufreq_exit_governor(policy); | |
1da177e4 | 1597 | |
87549141 | 1598 | /* |
91a12e91 VK |
1599 | * Perform the ->offline() during light-weight tear-down, as |
1600 | * that allows fast recovery when the CPU comes back. | |
87549141 | 1601 | */ |
91a12e91 VK |
1602 | if (cpufreq_driver->offline) { |
1603 | cpufreq_driver->offline(policy); | |
1604 | } else if (cpufreq_driver->exit) { | |
87549141 | 1605 | cpufreq_driver->exit(policy); |
55582bcc SP |
1606 | policy->freq_table = NULL; |
1607 | } | |
49f18560 VK |
1608 | |
1609 | unlock: | |
1610 | up_write(&policy->rwsem); | |
27622b06 | 1611 | return 0; |
1da177e4 LT |
1612 | } |
1613 | ||
cedb70af | 1614 | /** |
27a862e9 | 1615 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1616 | * |
1617 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1618 | */ |
71db87ba | 1619 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1620 | { |
8a25a2fd | 1621 | unsigned int cpu = dev->id; |
559ed407 | 1622 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1623 | |
559ed407 | 1624 | if (!policy) |
1af115d6 | 1625 | return; |
87549141 | 1626 | |
69cee714 VK |
1627 | if (cpu_online(cpu)) |
1628 | cpufreq_offline(cpu); | |
87549141 | 1629 | |
559ed407 | 1630 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1631 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1632 | |
91a12e91 VK |
1633 | if (cpumask_empty(policy->real_cpus)) { |
1634 | /* We did light-weight exit earlier, do full tear down now */ | |
1635 | if (cpufreq_driver->offline) | |
1636 | cpufreq_driver->exit(policy); | |
1637 | ||
f9f41e3e | 1638 | cpufreq_policy_free(policy); |
91a12e91 | 1639 | } |
5a01f2e8 VP |
1640 | } |
1641 | ||
1da177e4 | 1642 | /** |
bb176f7d VK |
1643 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1644 | * in deep trouble. | |
a1e1dc41 | 1645 | * @policy: policy managing CPUs |
1da177e4 LT |
1646 | * @new_freq: CPU frequency the CPU actually runs at |
1647 | * | |
29464f28 DJ |
1648 | * We adjust to current frequency first, and need to clean up later. |
1649 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1650 | */ |
a1e1dc41 | 1651 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1652 | unsigned int new_freq) |
1da177e4 LT |
1653 | { |
1654 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1655 | |
e837f9b5 | 1656 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1657 | policy->cur, new_freq); |
1da177e4 | 1658 | |
a1e1dc41 | 1659 | freqs.old = policy->cur; |
1da177e4 | 1660 | freqs.new = new_freq; |
b43a7ffb | 1661 | |
8fec051e VK |
1662 | cpufreq_freq_transition_begin(policy, &freqs); |
1663 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1664 | } |
1665 | ||
5980752e VK |
1666 | static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update) |
1667 | { | |
1668 | unsigned int new_freq; | |
1669 | ||
1670 | new_freq = cpufreq_driver->get(policy->cpu); | |
1671 | if (!new_freq) | |
1672 | return 0; | |
1673 | ||
1674 | /* | |
1675 | * If fast frequency switching is used with the given policy, the check | |
1676 | * against policy->cur is pointless, so skip it in that case. | |
1677 | */ | |
1678 | if (policy->fast_switch_enabled || !has_target()) | |
1679 | return new_freq; | |
1680 | ||
1681 | if (policy->cur != new_freq) { | |
1682 | cpufreq_out_of_sync(policy, new_freq); | |
1683 | if (update) | |
1684 | schedule_work(&policy->update); | |
1685 | } | |
1686 | ||
1687 | return new_freq; | |
1688 | } | |
1689 | ||
32ee8c3e | 1690 | /** |
4ab70df4 | 1691 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1692 | * @cpu: CPU number |
1693 | * | |
1694 | * This is the last known freq, without actually getting it from the driver. | |
1695 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1696 | */ | |
1697 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1698 | { | |
9e21ba8b | 1699 | struct cpufreq_policy *policy; |
e08f5f5b | 1700 | unsigned int ret_freq = 0; |
c75361c0 | 1701 | unsigned long flags; |
95235ca2 | 1702 | |
c75361c0 RC |
1703 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1704 | ||
1705 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1706 | ret_freq = cpufreq_driver->get(cpu); | |
1707 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1708 | return ret_freq; | |
1709 | } | |
1710 | ||
1711 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1712 | |
1713 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1714 | if (policy) { |
e08f5f5b | 1715 | ret_freq = policy->cur; |
95235ca2 VP |
1716 | cpufreq_cpu_put(policy); |
1717 | } | |
1718 | ||
4d34a67d | 1719 | return ret_freq; |
95235ca2 VP |
1720 | } |
1721 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1722 | ||
3d737108 JB |
1723 | /** |
1724 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1725 | * @cpu: CPU number | |
1726 | * | |
1727 | * Just return the max possible frequency for a given CPU. | |
1728 | */ | |
1729 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1730 | { | |
1731 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1732 | unsigned int ret_freq = 0; | |
1733 | ||
1734 | if (policy) { | |
1735 | ret_freq = policy->max; | |
1736 | cpufreq_cpu_put(policy); | |
1737 | } | |
1738 | ||
1739 | return ret_freq; | |
1740 | } | |
1741 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1742 | ||
d92d50a4 | 1743 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1744 | { |
4db7c34c | 1745 | if (unlikely(policy_is_inactive(policy))) |
5980752e | 1746 | return 0; |
1da177e4 | 1747 | |
5980752e | 1748 | return cpufreq_verify_current_freq(policy, true); |
5a01f2e8 | 1749 | } |
1da177e4 | 1750 | |
5a01f2e8 VP |
1751 | /** |
1752 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1753 | * @cpu: CPU number | |
1754 | * | |
1755 | * Get the CPU current (static) CPU frequency | |
1756 | */ | |
1757 | unsigned int cpufreq_get(unsigned int cpu) | |
1758 | { | |
999976e0 | 1759 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1760 | unsigned int ret_freq = 0; |
5a01f2e8 | 1761 | |
999976e0 AP |
1762 | if (policy) { |
1763 | down_read(&policy->rwsem); | |
4db7c34c YH |
1764 | if (cpufreq_driver->get) |
1765 | ret_freq = __cpufreq_get(policy); | |
999976e0 | 1766 | up_read(&policy->rwsem); |
5a01f2e8 | 1767 | |
999976e0 AP |
1768 | cpufreq_cpu_put(policy); |
1769 | } | |
6eed9404 | 1770 | |
4d34a67d | 1771 | return ret_freq; |
1da177e4 LT |
1772 | } |
1773 | EXPORT_SYMBOL(cpufreq_get); | |
1774 | ||
8a25a2fd KS |
1775 | static struct subsys_interface cpufreq_interface = { |
1776 | .name = "cpufreq", | |
1777 | .subsys = &cpu_subsys, | |
1778 | .add_dev = cpufreq_add_dev, | |
1779 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1780 | }; |
1781 | ||
e28867ea VK |
1782 | /* |
1783 | * In case platform wants some specific frequency to be configured | |
1784 | * during suspend.. | |
1785 | */ | |
1786 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1787 | { | |
1788 | int ret; | |
1789 | ||
1790 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1791 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1792 | return 0; | |
e28867ea VK |
1793 | } |
1794 | ||
1795 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1796 | policy->suspend_freq); | |
1797 | ||
1798 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1799 | CPUFREQ_RELATION_H); | |
1800 | if (ret) | |
1801 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1802 | __func__, policy->suspend_freq, ret); | |
1803 | ||
1804 | return ret; | |
1805 | } | |
1806 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1807 | ||
42d4dc3f | 1808 | /** |
2f0aea93 | 1809 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1810 | * |
2f0aea93 VK |
1811 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1812 | * as some platforms can't change frequency after this point in suspend cycle. | |
1813 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1814 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1815 | */ |
2f0aea93 | 1816 | void cpufreq_suspend(void) |
42d4dc3f | 1817 | { |
3a3e9e06 | 1818 | struct cpufreq_policy *policy; |
42d4dc3f | 1819 | |
2f0aea93 VK |
1820 | if (!cpufreq_driver) |
1821 | return; | |
42d4dc3f | 1822 | |
ba41e1bc | 1823 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1824 | goto suspend; |
42d4dc3f | 1825 | |
2f0aea93 VK |
1826 | pr_debug("%s: Suspending Governors\n", __func__); |
1827 | ||
f963735a | 1828 | for_each_active_policy(policy) { |
ba41e1bc RW |
1829 | if (has_target()) { |
1830 | down_write(&policy->rwsem); | |
45482c70 | 1831 | cpufreq_stop_governor(policy); |
ba41e1bc | 1832 | up_write(&policy->rwsem); |
ba41e1bc RW |
1833 | } |
1834 | ||
1835 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
e9a7cc1d FF |
1836 | pr_err("%s: Failed to suspend driver: %s\n", __func__, |
1837 | cpufreq_driver->name); | |
42d4dc3f | 1838 | } |
b1b12bab VK |
1839 | |
1840 | suspend: | |
1841 | cpufreq_suspended = true; | |
42d4dc3f BH |
1842 | } |
1843 | ||
1da177e4 | 1844 | /** |
2f0aea93 | 1845 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1846 | * |
2f0aea93 VK |
1847 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1848 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1849 | */ |
2f0aea93 | 1850 | void cpufreq_resume(void) |
1da177e4 | 1851 | { |
3a3e9e06 | 1852 | struct cpufreq_policy *policy; |
49f18560 | 1853 | int ret; |
1da177e4 | 1854 | |
2f0aea93 | 1855 | if (!cpufreq_driver) |
703cbaa6 BY |
1856 | return; |
1857 | ||
1858 | if (unlikely(!cpufreq_suspended)) | |
2f0aea93 | 1859 | return; |
1da177e4 | 1860 | |
8e30444e LT |
1861 | cpufreq_suspended = false; |
1862 | ||
ba41e1bc | 1863 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1864 | return; |
1da177e4 | 1865 | |
2f0aea93 | 1866 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1867 | |
f963735a | 1868 | for_each_active_policy(policy) { |
49f18560 | 1869 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1870 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1871 | policy); | |
ba41e1bc | 1872 | } else if (has_target()) { |
49f18560 | 1873 | down_write(&policy->rwsem); |
0a300767 | 1874 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1875 | up_write(&policy->rwsem); |
1876 | ||
1877 | if (ret) | |
1878 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1879 | __func__, policy); | |
1880 | } | |
2f0aea93 VK |
1881 | } |
1882 | } | |
1da177e4 | 1883 | |
9d95046e BP |
1884 | /** |
1885 | * cpufreq_get_current_driver - return current driver's name | |
1886 | * | |
1887 | * Return the name string of the currently loaded cpufreq driver | |
1888 | * or NULL, if none. | |
1889 | */ | |
1890 | const char *cpufreq_get_current_driver(void) | |
1891 | { | |
1c3d85dd RW |
1892 | if (cpufreq_driver) |
1893 | return cpufreq_driver->name; | |
1894 | ||
1895 | return NULL; | |
9d95046e BP |
1896 | } |
1897 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1898 | |
51315cdf TP |
1899 | /** |
1900 | * cpufreq_get_driver_data - return current driver data | |
1901 | * | |
1902 | * Return the private data of the currently loaded cpufreq | |
1903 | * driver, or NULL if no cpufreq driver is loaded. | |
1904 | */ | |
1905 | void *cpufreq_get_driver_data(void) | |
1906 | { | |
1907 | if (cpufreq_driver) | |
1908 | return cpufreq_driver->driver_data; | |
1909 | ||
1910 | return NULL; | |
1911 | } | |
1912 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1913 | ||
1da177e4 LT |
1914 | /********************************************************************* |
1915 | * NOTIFIER LISTS INTERFACE * | |
1916 | *********************************************************************/ | |
1917 | ||
1918 | /** | |
1919 | * cpufreq_register_notifier - register a driver with cpufreq | |
1920 | * @nb: notifier function to register | |
1921 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1922 | * | |
32ee8c3e | 1923 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1924 | * are notified about clock rate changes (once before and once after |
1925 | * the transition), or a list of drivers that are notified about | |
1926 | * changes in cpufreq policy. | |
1927 | * | |
1928 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1929 | * blocking_notifier_chain_register. |
1da177e4 LT |
1930 | */ |
1931 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1932 | { | |
1933 | int ret; | |
1934 | ||
d5aaffa9 DB |
1935 | if (cpufreq_disabled()) |
1936 | return -EINVAL; | |
1937 | ||
1da177e4 LT |
1938 | switch (list) { |
1939 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1940 | mutex_lock(&cpufreq_fast_switch_lock); |
1941 | ||
1942 | if (cpufreq_fast_switch_count > 0) { | |
1943 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1944 | return -EBUSY; | |
1945 | } | |
b4dfdbb3 | 1946 | ret = srcu_notifier_chain_register( |
e041c683 | 1947 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1948 | if (!ret) |
1949 | cpufreq_fast_switch_count--; | |
1950 | ||
1951 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1952 | break; |
1953 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1954 | ret = blocking_notifier_chain_register( |
1955 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1956 | break; |
1957 | default: | |
1958 | ret = -EINVAL; | |
1959 | } | |
1da177e4 LT |
1960 | |
1961 | return ret; | |
1962 | } | |
1963 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1964 | ||
1da177e4 LT |
1965 | /** |
1966 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1967 | * @nb: notifier block to be unregistered | |
bb176f7d | 1968 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1969 | * |
1970 | * Remove a driver from the CPU frequency notifier list. | |
1971 | * | |
1972 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1973 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1974 | */ |
1975 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1976 | { | |
1977 | int ret; | |
1978 | ||
d5aaffa9 DB |
1979 | if (cpufreq_disabled()) |
1980 | return -EINVAL; | |
1981 | ||
1da177e4 LT |
1982 | switch (list) { |
1983 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1984 | mutex_lock(&cpufreq_fast_switch_lock); |
1985 | ||
b4dfdbb3 | 1986 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1987 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1988 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
1989 | cpufreq_fast_switch_count++; | |
1990 | ||
1991 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1992 | break; |
1993 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1994 | ret = blocking_notifier_chain_unregister( |
1995 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1996 | break; |
1997 | default: | |
1998 | ret = -EINVAL; | |
1999 | } | |
1da177e4 LT |
2000 | |
2001 | return ret; | |
2002 | } | |
2003 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
2004 | ||
2005 | ||
2006 | /********************************************************************* | |
2007 | * GOVERNORS * | |
2008 | *********************************************************************/ | |
2009 | ||
b7898fda RW |
2010 | /** |
2011 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
2012 | * @policy: cpufreq policy to switch the frequency for. | |
2013 | * @target_freq: New frequency to set (may be approximate). | |
2014 | * | |
2015 | * Carry out a fast frequency switch without sleeping. | |
2016 | * | |
2017 | * The driver's ->fast_switch() callback invoked by this function must be | |
2018 | * suitable for being called from within RCU-sched read-side critical sections | |
2019 | * and it is expected to select the minimum available frequency greater than or | |
2020 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
2021 | * | |
2022 | * This function must not be called if policy->fast_switch_enabled is unset. | |
2023 | * | |
2024 | * Governors calling this function must guarantee that it will never be invoked | |
2025 | * twice in parallel for the same policy and that it will never be called in | |
2026 | * parallel with either ->target() or ->target_index() for the same policy. | |
2027 | * | |
209887e6 VK |
2028 | * Returns the actual frequency set for the CPU. |
2029 | * | |
2030 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
2031 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
2032 | */ |
2033 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
2034 | unsigned int target_freq) | |
2035 | { | |
b9af6948 | 2036 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
b7898fda RW |
2037 | |
2038 | return cpufreq_driver->fast_switch(policy, target_freq); | |
2039 | } | |
2040 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
2041 | ||
1c03a2d0 VK |
2042 | /* Must set freqs->new to intermediate frequency */ |
2043 | static int __target_intermediate(struct cpufreq_policy *policy, | |
2044 | struct cpufreq_freqs *freqs, int index) | |
2045 | { | |
2046 | int ret; | |
2047 | ||
2048 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
2049 | ||
2050 | /* We don't need to switch to intermediate freq */ | |
2051 | if (!freqs->new) | |
2052 | return 0; | |
2053 | ||
2054 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
2055 | __func__, policy->cpu, freqs->old, freqs->new); | |
2056 | ||
2057 | cpufreq_freq_transition_begin(policy, freqs); | |
2058 | ret = cpufreq_driver->target_intermediate(policy, index); | |
2059 | cpufreq_freq_transition_end(policy, freqs, ret); | |
2060 | ||
2061 | if (ret) | |
2062 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
2063 | __func__, ret); | |
2064 | ||
2065 | return ret; | |
2066 | } | |
2067 | ||
23727845 | 2068 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 2069 | { |
1c03a2d0 VK |
2070 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
2071 | unsigned int intermediate_freq = 0; | |
23727845 | 2072 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
2073 | int retval = -EINVAL; |
2074 | bool notify; | |
2075 | ||
23727845 VK |
2076 | if (newfreq == policy->cur) |
2077 | return 0; | |
2078 | ||
8d65775d | 2079 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 2080 | if (notify) { |
1c03a2d0 VK |
2081 | /* Handle switching to intermediate frequency */ |
2082 | if (cpufreq_driver->get_intermediate) { | |
2083 | retval = __target_intermediate(policy, &freqs, index); | |
2084 | if (retval) | |
2085 | return retval; | |
2086 | ||
2087 | intermediate_freq = freqs.new; | |
2088 | /* Set old freq to intermediate */ | |
2089 | if (intermediate_freq) | |
2090 | freqs.old = freqs.new; | |
2091 | } | |
8d65775d | 2092 | |
23727845 | 2093 | freqs.new = newfreq; |
8d65775d VK |
2094 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
2095 | __func__, policy->cpu, freqs.old, freqs.new); | |
2096 | ||
2097 | cpufreq_freq_transition_begin(policy, &freqs); | |
2098 | } | |
2099 | ||
2100 | retval = cpufreq_driver->target_index(policy, index); | |
2101 | if (retval) | |
2102 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
2103 | retval); | |
2104 | ||
1c03a2d0 | 2105 | if (notify) { |
8d65775d VK |
2106 | cpufreq_freq_transition_end(policy, &freqs, retval); |
2107 | ||
1c03a2d0 VK |
2108 | /* |
2109 | * Failed after setting to intermediate freq? Driver should have | |
2110 | * reverted back to initial frequency and so should we. Check | |
2111 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 2112 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
2113 | */ |
2114 | if (unlikely(retval && intermediate_freq)) { | |
2115 | freqs.old = intermediate_freq; | |
2116 | freqs.new = policy->restore_freq; | |
2117 | cpufreq_freq_transition_begin(policy, &freqs); | |
2118 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
2119 | } | |
2120 | } | |
2121 | ||
8d65775d VK |
2122 | return retval; |
2123 | } | |
2124 | ||
1da177e4 LT |
2125 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
2126 | unsigned int target_freq, | |
2127 | unsigned int relation) | |
2128 | { | |
7249924e | 2129 | unsigned int old_target_freq = target_freq; |
d218ed77 | 2130 | int index; |
c32b6b8e | 2131 | |
a7b422cd KRW |
2132 | if (cpufreq_disabled()) |
2133 | return -ENODEV; | |
2134 | ||
7249924e | 2135 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 2136 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
2137 | |
2138 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2139 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2140 | |
9c0ebcf7 VK |
2141 | /* |
2142 | * This might look like a redundant call as we are checking it again | |
2143 | * after finding index. But it is left intentionally for cases where | |
2144 | * exactly same freq is called again and so we can save on few function | |
2145 | * calls. | |
2146 | */ | |
5a1c0228 VK |
2147 | if (target_freq == policy->cur) |
2148 | return 0; | |
2149 | ||
1c03a2d0 VK |
2150 | /* Save last value to restore later on errors */ |
2151 | policy->restore_freq = policy->cur; | |
2152 | ||
1c3d85dd | 2153 | if (cpufreq_driver->target) |
6019d23a | 2154 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 2155 | |
6019d23a RW |
2156 | if (!cpufreq_driver->target_index) |
2157 | return -EINVAL; | |
9c0ebcf7 | 2158 | |
d218ed77 | 2159 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 2160 | |
23727845 | 2161 | return __target_index(policy, index); |
1da177e4 LT |
2162 | } |
2163 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2164 | ||
1da177e4 LT |
2165 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2166 | unsigned int target_freq, | |
2167 | unsigned int relation) | |
2168 | { | |
62c23a89 | 2169 | int ret; |
1da177e4 | 2170 | |
ad7722da | 2171 | down_write(&policy->rwsem); |
1da177e4 LT |
2172 | |
2173 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2174 | ||
ad7722da | 2175 | up_write(&policy->rwsem); |
1da177e4 | 2176 | |
1da177e4 LT |
2177 | return ret; |
2178 | } | |
2179 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2180 | ||
de1df26b RW |
2181 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2182 | { | |
2183 | return NULL; | |
2184 | } | |
2185 | ||
a92604b4 | 2186 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2187 | { |
cc993cab | 2188 | int ret; |
6afde10c | 2189 | |
2f0aea93 VK |
2190 | /* Don't start any governor operations if we are entering suspend */ |
2191 | if (cpufreq_suspended) | |
2192 | return 0; | |
cb57720b EZ |
2193 | /* |
2194 | * Governor might not be initiated here if ACPI _PPC changed | |
2195 | * notification happened, so check it. | |
2196 | */ | |
2197 | if (!policy->governor) | |
2198 | return -EINVAL; | |
2f0aea93 | 2199 | |
ed4676e2 VK |
2200 | /* Platform doesn't want dynamic frequency switching ? */ |
2201 | if (policy->governor->dynamic_switching && | |
fc4c709f | 2202 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2203 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2204 | ||
2205 | if (gov) { | |
fe829ed8 | 2206 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2207 | policy->governor->name, gov->name); |
6afde10c | 2208 | policy->governor = gov; |
de1df26b RW |
2209 | } else { |
2210 | return -EINVAL; | |
6afde10c | 2211 | } |
1c256245 | 2212 | } |
1da177e4 | 2213 | |
a92604b4 RW |
2214 | if (!try_module_get(policy->governor->owner)) |
2215 | return -EINVAL; | |
95731ebb | 2216 | |
a92604b4 | 2217 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2218 | |
e788892b RW |
2219 | if (policy->governor->init) { |
2220 | ret = policy->governor->init(policy); | |
2221 | if (ret) { | |
36be3418 | 2222 | module_put(policy->governor->owner); |
e788892b RW |
2223 | return ret; |
2224 | } | |
36be3418 | 2225 | } |
1da177e4 | 2226 | |
a92604b4 RW |
2227 | return 0; |
2228 | } | |
2229 | ||
2230 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2231 | { | |
2232 | if (cpufreq_suspended || !policy->governor) | |
2233 | return; | |
2234 | ||
2235 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2236 | ||
e788892b RW |
2237 | if (policy->governor->exit) |
2238 | policy->governor->exit(policy); | |
a92604b4 | 2239 | |
a92604b4 | 2240 | module_put(policy->governor->owner); |
1da177e4 LT |
2241 | } |
2242 | ||
0a300767 RW |
2243 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
2244 | { | |
2245 | int ret; | |
2246 | ||
a92604b4 RW |
2247 | if (cpufreq_suspended) |
2248 | return 0; | |
2249 | ||
2250 | if (!policy->governor) | |
2251 | return -EINVAL; | |
2252 | ||
2253 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2254 | ||
407d0fff | 2255 | if (cpufreq_driver->get) |
5980752e | 2256 | cpufreq_verify_current_freq(policy, false); |
3bbf8fe3 | 2257 | |
e788892b RW |
2258 | if (policy->governor->start) { |
2259 | ret = policy->governor->start(policy); | |
2260 | if (ret) | |
2261 | return ret; | |
2262 | } | |
2263 | ||
2264 | if (policy->governor->limits) | |
2265 | policy->governor->limits(policy); | |
d6ff44d6 | 2266 | |
d6ff44d6 | 2267 | return 0; |
0a300767 RW |
2268 | } |
2269 | ||
a92604b4 RW |
2270 | static void cpufreq_stop_governor(struct cpufreq_policy *policy) |
2271 | { | |
2272 | if (cpufreq_suspended || !policy->governor) | |
2273 | return; | |
2274 | ||
2275 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2276 | ||
e788892b RW |
2277 | if (policy->governor->stop) |
2278 | policy->governor->stop(policy); | |
a92604b4 RW |
2279 | } |
2280 | ||
2281 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2282 | { | |
2283 | if (cpufreq_suspended || !policy->governor) | |
2284 | return; | |
2285 | ||
2286 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2287 | ||
e788892b RW |
2288 | if (policy->governor->limits) |
2289 | policy->governor->limits(policy); | |
0a300767 RW |
2290 | } |
2291 | ||
1da177e4 LT |
2292 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2293 | { | |
3bcb09a3 | 2294 | int err; |
1da177e4 LT |
2295 | |
2296 | if (!governor) | |
2297 | return -EINVAL; | |
2298 | ||
a7b422cd KRW |
2299 | if (cpufreq_disabled()) |
2300 | return -ENODEV; | |
2301 | ||
3fc54d37 | 2302 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2303 | |
3bcb09a3 | 2304 | err = -EBUSY; |
42f91fa1 | 2305 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2306 | err = 0; |
2307 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2308 | } |
1da177e4 | 2309 | |
32ee8c3e | 2310 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2311 | return err; |
1da177e4 LT |
2312 | } |
2313 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2314 | ||
1da177e4 LT |
2315 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2316 | { | |
4573237b VK |
2317 | struct cpufreq_policy *policy; |
2318 | unsigned long flags; | |
90e41bac | 2319 | |
1da177e4 LT |
2320 | if (!governor) |
2321 | return; | |
2322 | ||
a7b422cd KRW |
2323 | if (cpufreq_disabled()) |
2324 | return; | |
2325 | ||
4573237b VK |
2326 | /* clear last_governor for all inactive policies */ |
2327 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2328 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2329 | if (!strcmp(policy->last_governor, governor->name)) { |
2330 | policy->governor = NULL; | |
4573237b | 2331 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2332 | } |
90e41bac | 2333 | } |
4573237b | 2334 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2335 | |
3fc54d37 | 2336 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2337 | list_del(&governor->governor_list); |
3fc54d37 | 2338 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2339 | } |
2340 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2341 | ||
2342 | ||
1da177e4 LT |
2343 | /********************************************************************* |
2344 | * POLICY INTERFACE * | |
2345 | *********************************************************************/ | |
2346 | ||
2347 | /** | |
2348 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2349 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2350 | * is written | |
1da177e4 LT |
2351 | * |
2352 | * Reads the current cpufreq policy. | |
2353 | */ | |
2354 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2355 | { | |
2356 | struct cpufreq_policy *cpu_policy; | |
2357 | if (!policy) | |
2358 | return -EINVAL; | |
2359 | ||
2360 | cpu_policy = cpufreq_cpu_get(cpu); | |
2361 | if (!cpu_policy) | |
2362 | return -EINVAL; | |
2363 | ||
d5b73cd8 | 2364 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2365 | |
2366 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2367 | return 0; |
2368 | } | |
2369 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2370 | ||
a0dbb819 RW |
2371 | /** |
2372 | * cpufreq_set_policy - Modify cpufreq policy parameters. | |
2373 | * @policy: Policy object to modify. | |
aed8e0a1 RW |
2374 | * @new_gov: Policy governor pointer. |
2375 | * @new_pol: Policy value (for drivers with built-in governors). | |
a0dbb819 | 2376 | * |
aed8e0a1 RW |
2377 | * Invoke the cpufreq driver's ->verify() callback to sanity-check the frequency |
2378 | * limits to be set for the policy, update @policy with the verified limits | |
2379 | * values and either invoke the driver's ->setpolicy() callback (if present) or | |
2380 | * carry out a governor update for @policy. That is, run the current governor's | |
2381 | * ->limits() callback (if @new_gov points to the same object as the one in | |
2382 | * @policy) or replace the governor for @policy with @new_gov. | |
a0dbb819 RW |
2383 | * |
2384 | * The cpuinfo part of @policy is not updated by this function. | |
153d7f3f | 2385 | */ |
aed8e0a1 RW |
2386 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
2387 | struct cpufreq_governor *new_gov, | |
2388 | unsigned int new_pol) | |
1da177e4 | 2389 | { |
aed8e0a1 | 2390 | struct cpufreq_policy_data new_data; |
d9a789c7 RW |
2391 | struct cpufreq_governor *old_gov; |
2392 | int ret; | |
1da177e4 | 2393 | |
aed8e0a1 RW |
2394 | memcpy(&new_data.cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
2395 | new_data.freq_table = policy->freq_table; | |
2396 | new_data.cpu = policy->cpu; | |
fba9573b | 2397 | /* |
67d874c3 VK |
2398 | * PM QoS framework collects all the requests from users and provide us |
2399 | * the final aggregated value here. | |
2400 | */ | |
aed8e0a1 RW |
2401 | new_data.min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN); |
2402 | new_data.max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX); | |
2403 | ||
2404 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", | |
2405 | new_data.cpu, new_data.min, new_data.max); | |
9c9a43ed | 2406 | |
1da177e4 | 2407 | /* verify the cpu speed can be set within this limit */ |
aed8e0a1 | 2408 | ret = cpufreq_driver->verify(&new_data); |
1da177e4 | 2409 | if (ret) |
d9a789c7 | 2410 | return ret; |
1da177e4 | 2411 | |
aed8e0a1 RW |
2412 | policy->min = new_data.min; |
2413 | policy->max = new_data.max; | |
601b2185 | 2414 | trace_cpu_frequency_limits(policy); |
1da177e4 | 2415 | |
e3c06236 SM |
2416 | policy->cached_target_freq = UINT_MAX; |
2417 | ||
2d06d8c4 | 2418 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2419 | policy->min, policy->max); |
1da177e4 | 2420 | |
1c3d85dd | 2421 | if (cpufreq_driver->setpolicy) { |
aed8e0a1 | 2422 | policy->policy = new_pol; |
2d06d8c4 | 2423 | pr_debug("setting range\n"); |
167a38dc | 2424 | return cpufreq_driver->setpolicy(policy); |
d9a789c7 | 2425 | } |
1da177e4 | 2426 | |
aed8e0a1 | 2427 | if (new_gov == policy->governor) { |
2bb4059e | 2428 | pr_debug("governor limits update\n"); |
a92604b4 | 2429 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2430 | return 0; |
0a300767 | 2431 | } |
7bd353a9 | 2432 | |
d9a789c7 RW |
2433 | pr_debug("governor switch\n"); |
2434 | ||
2435 | /* save old, working values */ | |
2436 | old_gov = policy->governor; | |
2437 | /* end old governor */ | |
2438 | if (old_gov) { | |
45482c70 | 2439 | cpufreq_stop_governor(policy); |
36be3418 | 2440 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2441 | } |
2442 | ||
d9a789c7 | 2443 | /* start new governor */ |
aed8e0a1 | 2444 | policy->governor = new_gov; |
a92604b4 | 2445 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2446 | if (!ret) { |
0a300767 RW |
2447 | ret = cpufreq_start_governor(policy); |
2448 | if (!ret) { | |
2bb4059e | 2449 | pr_debug("governor change\n"); |
531b5c9f | 2450 | sched_cpufreq_governor_change(policy, old_gov); |
0a300767 RW |
2451 | return 0; |
2452 | } | |
b7898fda | 2453 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2454 | } |
2455 | ||
2456 | /* new governor failed, so re-start old one */ | |
2457 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2458 | if (old_gov) { | |
2459 | policy->governor = old_gov; | |
a92604b4 | 2460 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2461 | policy->governor = NULL; |
2462 | else | |
0a300767 | 2463 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2464 | } |
2465 | ||
4bc384ae | 2466 | return ret; |
1da177e4 LT |
2467 | } |
2468 | ||
1da177e4 | 2469 | /** |
a0dbb819 RW |
2470 | * cpufreq_update_policy - Re-evaluate an existing cpufreq policy. |
2471 | * @cpu: CPU to re-evaluate the policy for. | |
1da177e4 | 2472 | * |
a0dbb819 | 2473 | * Update the current frequency for the cpufreq policy of @cpu and use |
18c49926 VK |
2474 | * cpufreq_set_policy() to re-apply the min and max limits, which triggers the |
2475 | * evaluation of policy notifiers and the cpufreq driver's ->verify() callback | |
2476 | * for the policy in question, among other things. | |
1da177e4 | 2477 | */ |
30248fef | 2478 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2479 | { |
540a3758 | 2480 | struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu); |
1da177e4 | 2481 | |
fefa8ff8 | 2482 | if (!policy) |
30248fef | 2483 | return; |
1da177e4 | 2484 | |
bb176f7d VK |
2485 | /* |
2486 | * BIOS might change freq behind our back | |
2487 | * -> ask driver for current freq and notify governors about a change | |
2488 | */ | |
5ddc6d4e | 2489 | if (cpufreq_driver->get && has_target() && |
5980752e | 2490 | (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false)))) |
348a2ec5 | 2491 | goto unlock; |
30248fef | 2492 | |
70a59fde | 2493 | refresh_frequency_limits(policy); |
1da177e4 | 2494 | |
fefa8ff8 | 2495 | unlock: |
540a3758 | 2496 | cpufreq_cpu_release(policy); |
1da177e4 LT |
2497 | } |
2498 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2499 | ||
5a25e3f7 RW |
2500 | /** |
2501 | * cpufreq_update_limits - Update policy limits for a given CPU. | |
2502 | * @cpu: CPU to update the policy limits for. | |
2503 | * | |
2504 | * Invoke the driver's ->update_limits callback if present or call | |
2505 | * cpufreq_update_policy() for @cpu. | |
2506 | */ | |
2507 | void cpufreq_update_limits(unsigned int cpu) | |
2508 | { | |
2509 | if (cpufreq_driver->update_limits) | |
2510 | cpufreq_driver->update_limits(cpu); | |
2511 | else | |
2512 | cpufreq_update_policy(cpu); | |
2513 | } | |
2514 | EXPORT_SYMBOL_GPL(cpufreq_update_limits); | |
2515 | ||
6f19efc0 LM |
2516 | /********************************************************************* |
2517 | * BOOST * | |
2518 | *********************************************************************/ | |
2519 | static int cpufreq_boost_set_sw(int state) | |
2520 | { | |
6f19efc0 | 2521 | struct cpufreq_policy *policy; |
6f19efc0 | 2522 | |
f963735a | 2523 | for_each_active_policy(policy) { |
155096a6 RW |
2524 | int ret; |
2525 | ||
f8bfc116 | 2526 | if (!policy->freq_table) |
155096a6 | 2527 | return -ENXIO; |
49f18560 | 2528 | |
f8bfc116 VK |
2529 | ret = cpufreq_frequency_table_cpuinfo(policy, |
2530 | policy->freq_table); | |
2531 | if (ret) { | |
2532 | pr_err("%s: Policy frequency update failed\n", | |
2533 | __func__); | |
155096a6 | 2534 | return ret; |
6f19efc0 | 2535 | } |
f8bfc116 | 2536 | |
3000ce3c | 2537 | ret = freq_qos_update_request(policy->max_freq_req, policy->max); |
e61a4125 | 2538 | if (ret < 0) |
155096a6 | 2539 | return ret; |
6f19efc0 LM |
2540 | } |
2541 | ||
155096a6 | 2542 | return 0; |
6f19efc0 LM |
2543 | } |
2544 | ||
2545 | int cpufreq_boost_trigger_state(int state) | |
2546 | { | |
2547 | unsigned long flags; | |
2548 | int ret = 0; | |
2549 | ||
2550 | if (cpufreq_driver->boost_enabled == state) | |
2551 | return 0; | |
2552 | ||
2553 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2554 | cpufreq_driver->boost_enabled = state; | |
2555 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2556 | ||
2557 | ret = cpufreq_driver->set_boost(state); | |
2558 | if (ret) { | |
2559 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2560 | cpufreq_driver->boost_enabled = !state; | |
2561 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2562 | ||
e837f9b5 JP |
2563 | pr_err("%s: Cannot %s BOOST\n", |
2564 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2565 | } |
2566 | ||
2567 | return ret; | |
2568 | } | |
2569 | ||
41669da0 | 2570 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2571 | { |
89f98d7e | 2572 | return cpufreq_driver->set_boost; |
6f19efc0 | 2573 | } |
6f19efc0 | 2574 | |
44139ed4 VK |
2575 | static int create_boost_sysfs_file(void) |
2576 | { | |
2577 | int ret; | |
2578 | ||
c82bd444 | 2579 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2580 | if (ret) |
2581 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2582 | __func__); | |
2583 | ||
2584 | return ret; | |
2585 | } | |
2586 | ||
2587 | static void remove_boost_sysfs_file(void) | |
2588 | { | |
2589 | if (cpufreq_boost_supported()) | |
c82bd444 | 2590 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2591 | } |
2592 | ||
2593 | int cpufreq_enable_boost_support(void) | |
2594 | { | |
2595 | if (!cpufreq_driver) | |
2596 | return -EINVAL; | |
2597 | ||
2598 | if (cpufreq_boost_supported()) | |
2599 | return 0; | |
2600 | ||
7a6c79f2 | 2601 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2602 | |
2603 | /* This will get removed on driver unregister */ | |
2604 | return create_boost_sysfs_file(); | |
2605 | } | |
2606 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2607 | ||
6f19efc0 LM |
2608 | int cpufreq_boost_enabled(void) |
2609 | { | |
2610 | return cpufreq_driver->boost_enabled; | |
2611 | } | |
2612 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2613 | ||
1da177e4 LT |
2614 | /********************************************************************* |
2615 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2616 | *********************************************************************/ | |
27622b06 | 2617 | static enum cpuhp_state hp_online; |
1da177e4 | 2618 | |
c4a3fa26 CY |
2619 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2620 | { | |
2621 | cpufreq_online(cpu); | |
2622 | ||
2623 | return 0; | |
2624 | } | |
2625 | ||
2626 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2627 | { | |
2628 | cpufreq_offline(cpu); | |
2629 | ||
2630 | return 0; | |
2631 | } | |
2632 | ||
3ee81b45 TG |
2633 | static char cpufreq_driver_name[CPUFREQ_NAME_LEN]; |
2634 | ||
2635 | static int __init cpufreq_driver_setup(char *str) | |
2636 | { | |
2637 | strlcpy(cpufreq_driver_name, str, CPUFREQ_NAME_LEN); | |
2638 | return 1; | |
2639 | } | |
2640 | ||
2641 | /* | |
2642 | * Set this name to only allow one specific cpu freq driver, e.g., | |
2643 | * cpufreq_driver=powernow-k8 | |
2644 | */ | |
2645 | __setup("cpufreq_driver=", cpufreq_driver_setup); | |
2646 | ||
1da177e4 LT |
2647 | /** |
2648 | * cpufreq_register_driver - register a CPU Frequency driver | |
2649 | * @driver_data: A struct cpufreq_driver containing the values# | |
2650 | * submitted by the CPU Frequency driver. | |
2651 | * | |
bb176f7d | 2652 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2653 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2654 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2655 | * |
2656 | */ | |
221dee28 | 2657 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2658 | { |
2659 | unsigned long flags; | |
2660 | int ret; | |
2661 | ||
a7b422cd KRW |
2662 | if (cpufreq_disabled()) |
2663 | return -ENODEV; | |
2664 | ||
d97f8989 VK |
2665 | /* |
2666 | * The cpufreq core depends heavily on the availability of device | |
2667 | * structure, make sure they are available before proceeding further. | |
2668 | */ | |
2669 | if (!get_cpu_device(0)) | |
2670 | return -EPROBE_DEFER; | |
2671 | ||
1da177e4 | 2672 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2673 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2674 | driver_data->target) || |
2675 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 | 2676 | driver_data->target)) || |
a9a22b57 | 2677 | (!driver_data->get_intermediate != !driver_data->target_intermediate) || |
91a12e91 | 2678 | (!driver_data->online != !driver_data->offline)) |
1da177e4 LT |
2679 | return -EINVAL; |
2680 | ||
3ee81b45 TG |
2681 | pr_debug("trying to register driver %s, cpufreq_driver=%s\n", |
2682 | driver_data->name, cpufreq_driver_name); | |
2683 | ||
2684 | if (cpufreq_driver_name[0]) | |
2685 | if (!driver_data->name || | |
2686 | strcmp(cpufreq_driver_name, driver_data->name)) | |
2687 | return -EINVAL; | |
1da177e4 | 2688 | |
fdd320da | 2689 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2690 | cpus_read_lock(); |
fdd320da | 2691 | |
0d1857a1 | 2692 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2693 | if (cpufreq_driver) { |
0d1857a1 | 2694 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2695 | ret = -EEXIST; |
2696 | goto out; | |
1da177e4 | 2697 | } |
1c3d85dd | 2698 | cpufreq_driver = driver_data; |
0d1857a1 | 2699 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2700 | |
bc68b7df VK |
2701 | if (driver_data->setpolicy) |
2702 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2703 | ||
7a6c79f2 RW |
2704 | if (cpufreq_boost_supported()) { |
2705 | ret = create_boost_sysfs_file(); | |
2706 | if (ret) | |
2707 | goto err_null_driver; | |
2708 | } | |
6f19efc0 | 2709 | |
8a25a2fd | 2710 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2711 | if (ret) |
6f19efc0 | 2712 | goto err_boost_unreg; |
1da177e4 | 2713 | |
ce1bcfe9 VK |
2714 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2715 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2716 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2717 | ret = -ENODEV; |
ce1bcfe9 VK |
2718 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2719 | driver_data->name); | |
2720 | goto err_if_unreg; | |
1da177e4 LT |
2721 | } |
2722 | ||
a92551e4 SAS |
2723 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2724 | "cpufreq:online", | |
2725 | cpuhp_cpufreq_online, | |
2726 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2727 | if (ret < 0) |
2728 | goto err_if_unreg; | |
2729 | hp_online = ret; | |
5372e054 | 2730 | ret = 0; |
27622b06 | 2731 | |
2d06d8c4 | 2732 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2733 | goto out; |
fdd320da | 2734 | |
8a25a2fd KS |
2735 | err_if_unreg: |
2736 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2737 | err_boost_unreg: |
44139ed4 | 2738 | remove_boost_sysfs_file(); |
8f5bc2ab | 2739 | err_null_driver: |
0d1857a1 | 2740 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2741 | cpufreq_driver = NULL; |
0d1857a1 | 2742 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2743 | out: |
a92551e4 | 2744 | cpus_read_unlock(); |
3834abb4 | 2745 | return ret; |
1da177e4 LT |
2746 | } |
2747 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2748 | ||
1da177e4 LT |
2749 | /** |
2750 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2751 | * | |
bb176f7d | 2752 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2753 | * the right to do so, i.e. if you have succeeded in initialising before! |
2754 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2755 | * currently not initialised. | |
2756 | */ | |
221dee28 | 2757 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2758 | { |
2759 | unsigned long flags; | |
2760 | ||
1c3d85dd | 2761 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2762 | return -EINVAL; |
1da177e4 | 2763 | |
2d06d8c4 | 2764 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2765 | |
454d3a25 | 2766 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2767 | cpus_read_lock(); |
8a25a2fd | 2768 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2769 | remove_boost_sysfs_file(); |
a92551e4 | 2770 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2771 | |
0d1857a1 | 2772 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2773 | |
1c3d85dd | 2774 | cpufreq_driver = NULL; |
6eed9404 | 2775 | |
0d1857a1 | 2776 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2777 | cpus_read_unlock(); |
1da177e4 LT |
2778 | |
2779 | return 0; | |
2780 | } | |
2781 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2782 | |
c82bd444 VK |
2783 | struct kobject *cpufreq_global_kobject; |
2784 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2785 | ||
5a01f2e8 VP |
2786 | static int __init cpufreq_core_init(void) |
2787 | { | |
a7b422cd KRW |
2788 | if (cpufreq_disabled()) |
2789 | return -ENODEV; | |
2790 | ||
8eec1020 | 2791 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2792 | BUG_ON(!cpufreq_global_kobject); |
2793 | ||
5a01f2e8 VP |
2794 | return 0; |
2795 | } | |
d82f2692 | 2796 | module_param(off, int, 0444); |
5a01f2e8 | 2797 | core_initcall(cpufreq_core_init); |