]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
2f0aea93 | 29 | #include <linux/suspend.h> |
90de2a4a | 30 | #include <linux/syscore_ops.h> |
5ff0a268 | 31 | #include <linux/tick.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
b4f0676f | 34 | static LIST_HEAD(cpufreq_policy_list); |
f963735a VK |
35 | |
36 | static inline bool policy_is_inactive(struct cpufreq_policy *policy) | |
37 | { | |
38 | return cpumask_empty(policy->cpus); | |
39 | } | |
40 | ||
f963735a | 41 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
42 | #define for_each_suitable_policy(__policy, __active) \ |
43 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
44 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
45 | |
46 | #define for_each_active_policy(__policy) \ | |
47 | for_each_suitable_policy(__policy, true) | |
48 | #define for_each_inactive_policy(__policy) \ | |
49 | for_each_suitable_policy(__policy, false) | |
50 | ||
51 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
52 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
53 | ||
f7b27061 VK |
54 | /* Iterate over governors */ |
55 | static LIST_HEAD(cpufreq_governor_list); | |
56 | #define for_each_governor(__governor) \ | |
57 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
58 | ||
1da177e4 | 59 | /** |
cd878479 | 60 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
61 | * level driver of CPUFreq support, and its spinlock. This lock |
62 | * also protects the cpufreq_cpu_data array. | |
63 | */ | |
1c3d85dd | 64 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 65 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 66 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 67 | |
2f0aea93 VK |
68 | /* Flag to suspend/resume CPUFreq governors */ |
69 | static bool cpufreq_suspended; | |
1da177e4 | 70 | |
9c0ebcf7 VK |
71 | static inline bool has_target(void) |
72 | { | |
73 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
74 | } | |
75 | ||
1da177e4 | 76 | /* internal prototypes */ |
d92d50a4 | 77 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
78 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
79 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
0a300767 | 80 | static int cpufreq_start_governor(struct cpufreq_policy *policy); |
a92604b4 RW |
81 | static void cpufreq_stop_governor(struct cpufreq_policy *policy); |
82 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); | |
45482c70 | 83 | |
1da177e4 | 84 | /** |
32ee8c3e DJ |
85 | * Two notifier lists: the "policy" list is involved in the |
86 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
87 | * "transition" list for kernel code that needs to handle |
88 | * changes to devices when the CPU clock speed changes. | |
89 | * The mutex locks both lists. | |
90 | */ | |
e041c683 | 91 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 92 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 93 | |
74212ca4 | 94 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
95 | static int __init init_cpufreq_transition_notifier_list(void) |
96 | { | |
97 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 98 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
99 | return 0; |
100 | } | |
b3438f82 | 101 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 102 | |
a7b422cd | 103 | static int off __read_mostly; |
da584455 | 104 | static int cpufreq_disabled(void) |
a7b422cd KRW |
105 | { |
106 | return off; | |
107 | } | |
108 | void disable_cpufreq(void) | |
109 | { | |
110 | off = 1; | |
111 | } | |
29464f28 | 112 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 113 | |
4d5dcc42 VK |
114 | bool have_governor_per_policy(void) |
115 | { | |
0b981e70 | 116 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 117 | } |
3f869d6d | 118 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 119 | |
944e9a03 VK |
120 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
121 | { | |
122 | if (have_governor_per_policy()) | |
123 | return &policy->kobj; | |
124 | else | |
125 | return cpufreq_global_kobject; | |
126 | } | |
127 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
128 | ||
72a4ce34 VK |
129 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
130 | { | |
131 | u64 idle_time; | |
132 | u64 cur_wall_time; | |
133 | u64 busy_time; | |
134 | ||
7fb1327e | 135 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 VK |
136 | |
137 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
138 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
139 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
140 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
141 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
142 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
143 | ||
144 | idle_time = cur_wall_time - busy_time; | |
145 | if (wall) | |
7fb1327e | 146 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 147 | |
7fb1327e | 148 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
149 | } |
150 | ||
151 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
152 | { | |
153 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
154 | ||
155 | if (idle_time == -1ULL) | |
156 | return get_cpu_idle_time_jiffy(cpu, wall); | |
157 | else if (!io_busy) | |
158 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
159 | ||
160 | return idle_time; | |
161 | } | |
162 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
163 | ||
e7d5459d DE |
164 | __weak void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, |
165 | unsigned long max_freq) | |
166 | { | |
167 | } | |
168 | EXPORT_SYMBOL_GPL(arch_set_freq_scale); | |
169 | ||
70e9e778 VK |
170 | /* |
171 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
172 | * drivers of SMP systems. It will do following: | |
173 | * - validate & show freq table passed | |
174 | * - set policies transition latency | |
175 | * - policy->cpus with all possible CPUs | |
176 | */ | |
177 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
178 | struct cpufreq_frequency_table *table, | |
179 | unsigned int transition_latency) | |
180 | { | |
181 | int ret; | |
182 | ||
183 | ret = cpufreq_table_validate_and_show(policy, table); | |
184 | if (ret) { | |
185 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
186 | return ret; | |
187 | } | |
188 | ||
189 | policy->cpuinfo.transition_latency = transition_latency; | |
190 | ||
191 | /* | |
58405af6 | 192 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
193 | * share the clock and voltage and clock. |
194 | */ | |
195 | cpumask_setall(policy->cpus); | |
196 | ||
197 | return 0; | |
198 | } | |
199 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
200 | ||
1f0bd44e | 201 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
202 | { |
203 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
204 | ||
988bed09 VK |
205 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
206 | } | |
1f0bd44e | 207 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
208 | |
209 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
210 | { | |
211 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
212 | ||
652ed95d | 213 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
214 | pr_err("%s: No %s associated to cpu: %d\n", |
215 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
216 | return 0; |
217 | } | |
218 | ||
219 | return clk_get_rate(policy->clk) / 1000; | |
220 | } | |
221 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
222 | ||
50e9c852 VK |
223 | /** |
224 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
225 | * | |
226 | * @cpu: cpu to find policy for. | |
227 | * | |
228 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
229 | * It also increments the kobject reference count to mark it busy and so would | |
230 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
231 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
232 | * freed as that depends on the kobj count. | |
233 | * | |
50e9c852 VK |
234 | * Return: A valid policy on success, otherwise NULL on failure. |
235 | */ | |
6eed9404 | 236 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 237 | { |
6eed9404 | 238 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
239 | unsigned long flags; |
240 | ||
1b947c90 | 241 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
242 | return NULL; |
243 | ||
1da177e4 | 244 | /* get the cpufreq driver */ |
1c3d85dd | 245 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 246 | |
6eed9404 VK |
247 | if (cpufreq_driver) { |
248 | /* get the CPU */ | |
988bed09 | 249 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
250 | if (policy) |
251 | kobject_get(&policy->kobj); | |
252 | } | |
1da177e4 | 253 | |
6eed9404 | 254 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 255 | |
3a3e9e06 | 256 | return policy; |
a9144436 | 257 | } |
1da177e4 LT |
258 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
259 | ||
50e9c852 VK |
260 | /** |
261 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
262 | * | |
263 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
264 | * | |
265 | * This decrements the kobject reference count incremented earlier by calling | |
266 | * cpufreq_cpu_get(). | |
50e9c852 | 267 | */ |
3a3e9e06 | 268 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 269 | { |
6eed9404 | 270 | kobject_put(&policy->kobj); |
1da177e4 LT |
271 | } |
272 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
273 | ||
1da177e4 LT |
274 | /********************************************************************* |
275 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
276 | *********************************************************************/ | |
277 | ||
278 | /** | |
279 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
280 | * | |
281 | * This function alters the system "loops_per_jiffy" for the clock | |
282 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 283 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
284 | * per-CPU loops_per_jiffy value wherever possible. |
285 | */ | |
858119e1 | 286 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 287 | { |
39c132ee VK |
288 | #ifndef CONFIG_SMP |
289 | static unsigned long l_p_j_ref; | |
290 | static unsigned int l_p_j_ref_freq; | |
291 | ||
1da177e4 LT |
292 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
293 | return; | |
294 | ||
295 | if (!l_p_j_ref_freq) { | |
296 | l_p_j_ref = loops_per_jiffy; | |
297 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
298 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
299 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 300 | } |
0b443ead | 301 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
302 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
303 | ci->new); | |
e837f9b5 JP |
304 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
305 | loops_per_jiffy, ci->new); | |
1da177e4 | 306 | } |
1da177e4 | 307 | #endif |
39c132ee | 308 | } |
1da177e4 | 309 | |
0956df9c | 310 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 311 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
312 | { |
313 | BUG_ON(irqs_disabled()); | |
314 | ||
d5aaffa9 DB |
315 | if (cpufreq_disabled()) |
316 | return; | |
317 | ||
1c3d85dd | 318 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 319 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 320 | state, freqs->new); |
1da177e4 | 321 | |
1da177e4 | 322 | switch (state) { |
e4472cb3 | 323 | |
1da177e4 | 324 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 325 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
326 | * which is not equal to what the cpufreq core thinks is |
327 | * "old frequency". | |
1da177e4 | 328 | */ |
1c3d85dd | 329 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
330 | if ((policy) && (policy->cpu == freqs->cpu) && |
331 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
332 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
333 | freqs->old, policy->cur); | |
e4472cb3 | 334 | freqs->old = policy->cur; |
1da177e4 LT |
335 | } |
336 | } | |
b4dfdbb3 | 337 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 338 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
339 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
340 | break; | |
e4472cb3 | 341 | |
1da177e4 LT |
342 | case CPUFREQ_POSTCHANGE: |
343 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
344 | pr_debug("FREQ: %lu - CPU: %lu\n", |
345 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 346 | trace_cpu_frequency(freqs->new, freqs->cpu); |
1aefc75b | 347 | cpufreq_stats_record_transition(policy, freqs->new); |
b4dfdbb3 | 348 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 349 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
350 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
351 | policy->cur = freqs->new; | |
1da177e4 LT |
352 | break; |
353 | } | |
1da177e4 | 354 | } |
bb176f7d | 355 | |
b43a7ffb VK |
356 | /** |
357 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
358 | * on frequency transition. | |
359 | * | |
360 | * This function calls the transition notifiers and the "adjust_jiffies" | |
361 | * function. It is called twice on all CPU frequency changes that have | |
362 | * external effects. | |
363 | */ | |
236a9800 | 364 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
365 | struct cpufreq_freqs *freqs, unsigned int state) |
366 | { | |
367 | for_each_cpu(freqs->cpu, policy->cpus) | |
368 | __cpufreq_notify_transition(policy, freqs, state); | |
369 | } | |
1da177e4 | 370 | |
f7ba3b41 | 371 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 372 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
373 | struct cpufreq_freqs *freqs, int transition_failed) |
374 | { | |
375 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
376 | if (!transition_failed) | |
377 | return; | |
378 | ||
379 | swap(freqs->old, freqs->new); | |
380 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
381 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
382 | } | |
f7ba3b41 | 383 | |
12478cf0 SB |
384 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
385 | struct cpufreq_freqs *freqs) | |
386 | { | |
ca654dc3 SB |
387 | |
388 | /* | |
389 | * Catch double invocations of _begin() which lead to self-deadlock. | |
390 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
391 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
392 | * double invocations are very low. Moreover, there are scenarios | |
393 | * where these checks can emit false-positive warnings in these | |
394 | * drivers; so we avoid that by skipping them altogether. | |
395 | */ | |
396 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
397 | && current == policy->transition_task); | |
398 | ||
12478cf0 SB |
399 | wait: |
400 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
401 | ||
402 | spin_lock(&policy->transition_lock); | |
403 | ||
404 | if (unlikely(policy->transition_ongoing)) { | |
405 | spin_unlock(&policy->transition_lock); | |
406 | goto wait; | |
407 | } | |
408 | ||
409 | policy->transition_ongoing = true; | |
ca654dc3 | 410 | policy->transition_task = current; |
12478cf0 SB |
411 | |
412 | spin_unlock(&policy->transition_lock); | |
413 | ||
414 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
415 | } | |
416 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
417 | ||
418 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
419 | struct cpufreq_freqs *freqs, int transition_failed) | |
420 | { | |
421 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
422 | return; | |
423 | ||
424 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
425 | ||
426 | policy->transition_ongoing = false; | |
ca654dc3 | 427 | policy->transition_task = NULL; |
12478cf0 SB |
428 | |
429 | wake_up(&policy->transition_wait); | |
430 | } | |
431 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
432 | ||
b7898fda RW |
433 | /* |
434 | * Fast frequency switching status count. Positive means "enabled", negative | |
435 | * means "disabled" and 0 means "not decided yet". | |
436 | */ | |
437 | static int cpufreq_fast_switch_count; | |
438 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
439 | ||
440 | static void cpufreq_list_transition_notifiers(void) | |
441 | { | |
442 | struct notifier_block *nb; | |
443 | ||
444 | pr_info("Registered transition notifiers:\n"); | |
445 | ||
446 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
447 | ||
448 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
449 | pr_info("%pF\n", nb->notifier_call); | |
450 | ||
451 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
452 | } | |
453 | ||
454 | /** | |
455 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
456 | * @policy: cpufreq policy to enable fast frequency switching for. | |
457 | * | |
458 | * Try to enable fast frequency switching for @policy. | |
459 | * | |
460 | * The attempt will fail if there is at least one transition notifier registered | |
461 | * at this point, as fast frequency switching is quite fundamentally at odds | |
462 | * with transition notifiers. Thus if successful, it will make registration of | |
463 | * transition notifiers fail going forward. | |
464 | */ | |
465 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
466 | { | |
467 | lockdep_assert_held(&policy->rwsem); | |
468 | ||
469 | if (!policy->fast_switch_possible) | |
470 | return; | |
471 | ||
472 | mutex_lock(&cpufreq_fast_switch_lock); | |
473 | if (cpufreq_fast_switch_count >= 0) { | |
474 | cpufreq_fast_switch_count++; | |
475 | policy->fast_switch_enabled = true; | |
476 | } else { | |
477 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
478 | policy->cpu); | |
479 | cpufreq_list_transition_notifiers(); | |
480 | } | |
481 | mutex_unlock(&cpufreq_fast_switch_lock); | |
482 | } | |
483 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
484 | ||
6c9d9c81 RW |
485 | /** |
486 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
487 | * @policy: cpufreq policy to disable fast frequency switching for. | |
488 | */ | |
489 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
490 | { |
491 | mutex_lock(&cpufreq_fast_switch_lock); | |
492 | if (policy->fast_switch_enabled) { | |
493 | policy->fast_switch_enabled = false; | |
494 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
495 | cpufreq_fast_switch_count--; | |
496 | } | |
497 | mutex_unlock(&cpufreq_fast_switch_lock); | |
498 | } | |
6c9d9c81 | 499 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 500 | |
e3c06236 SM |
501 | /** |
502 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
503 | * one. | |
504 | * @target_freq: target frequency to resolve. | |
505 | * | |
506 | * The target to driver frequency mapping is cached in the policy. | |
507 | * | |
508 | * Return: Lowest driver-supported frequency greater than or equal to the | |
509 | * given target_freq, subject to policy (min/max) and driver limitations. | |
510 | */ | |
511 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
512 | unsigned int target_freq) | |
513 | { | |
514 | target_freq = clamp_val(target_freq, policy->min, policy->max); | |
515 | policy->cached_target_freq = target_freq; | |
abe8bd02 VK |
516 | |
517 | if (cpufreq_driver->target_index) { | |
518 | int idx; | |
519 | ||
520 | idx = cpufreq_frequency_table_target(policy, target_freq, | |
521 | CPUFREQ_RELATION_L); | |
522 | policy->cached_resolved_idx = idx; | |
523 | return policy->freq_table[idx].frequency; | |
524 | } | |
525 | ||
e3c06236 SM |
526 | if (cpufreq_driver->resolve_freq) |
527 | return cpufreq_driver->resolve_freq(policy, target_freq); | |
abe8bd02 VK |
528 | |
529 | return target_freq; | |
e3c06236 | 530 | } |
ae2c1ca6 | 531 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 532 | |
aa7519af VK |
533 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
534 | { | |
535 | unsigned int latency; | |
536 | ||
537 | if (policy->transition_delay_us) | |
538 | return policy->transition_delay_us; | |
539 | ||
540 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
e948bc8f VK |
541 | if (latency) { |
542 | /* | |
543 | * For platforms that can change the frequency very fast (< 10 | |
544 | * us), the above formula gives a decent transition delay. But | |
545 | * for platforms where transition_latency is in milliseconds, it | |
546 | * ends up giving unrealistic values. | |
547 | * | |
548 | * Cap the default transition delay to 10 ms, which seems to be | |
549 | * a reasonable amount of time after which we should reevaluate | |
550 | * the frequency. | |
551 | */ | |
552 | return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); | |
553 | } | |
aa7519af VK |
554 | |
555 | return LATENCY_MULTIPLIER; | |
556 | } | |
557 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
558 | ||
1da177e4 LT |
559 | /********************************************************************* |
560 | * SYSFS INTERFACE * | |
561 | *********************************************************************/ | |
8a5c74a1 | 562 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
563 | struct attribute *attr, char *buf) |
564 | { | |
565 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
566 | } | |
567 | ||
568 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
569 | const char *buf, size_t count) | |
570 | { | |
571 | int ret, enable; | |
572 | ||
573 | ret = sscanf(buf, "%d", &enable); | |
574 | if (ret != 1 || enable < 0 || enable > 1) | |
575 | return -EINVAL; | |
576 | ||
577 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
578 | pr_err("%s: Cannot %s BOOST!\n", |
579 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
580 | return -EINVAL; |
581 | } | |
582 | ||
e837f9b5 JP |
583 | pr_debug("%s: cpufreq BOOST %s\n", |
584 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
585 | |
586 | return count; | |
587 | } | |
588 | define_one_global_rw(boost); | |
1da177e4 | 589 | |
42f91fa1 | 590 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
591 | { |
592 | struct cpufreq_governor *t; | |
593 | ||
f7b27061 | 594 | for_each_governor(t) |
7c4f4539 | 595 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
596 | return t; |
597 | ||
598 | return NULL; | |
599 | } | |
600 | ||
1da177e4 LT |
601 | /** |
602 | * cpufreq_parse_governor - parse a governor string | |
603 | */ | |
905d77cd | 604 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
605 | struct cpufreq_governor **governor) |
606 | { | |
3bcb09a3 | 607 | int err = -EINVAL; |
1c3d85dd | 608 | |
1c3d85dd | 609 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 610 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 611 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 612 | err = 0; |
7c4f4539 | 613 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 614 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 615 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 616 | err = 0; |
1da177e4 | 617 | } |
2e1cc3a5 | 618 | } else { |
1da177e4 | 619 | struct cpufreq_governor *t; |
3bcb09a3 | 620 | |
3fc54d37 | 621 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 622 | |
42f91fa1 | 623 | t = find_governor(str_governor); |
3bcb09a3 | 624 | |
ea714970 | 625 | if (t == NULL) { |
1a8e1463 | 626 | int ret; |
ea714970 | 627 | |
1a8e1463 KC |
628 | mutex_unlock(&cpufreq_governor_mutex); |
629 | ret = request_module("cpufreq_%s", str_governor); | |
630 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 631 | |
1a8e1463 | 632 | if (ret == 0) |
42f91fa1 | 633 | t = find_governor(str_governor); |
ea714970 JF |
634 | } |
635 | ||
3bcb09a3 JF |
636 | if (t != NULL) { |
637 | *governor = t; | |
638 | err = 0; | |
1da177e4 | 639 | } |
3bcb09a3 | 640 | |
3fc54d37 | 641 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 642 | } |
3bcb09a3 | 643 | return err; |
1da177e4 | 644 | } |
1da177e4 | 645 | |
1da177e4 | 646 | /** |
e08f5f5b GS |
647 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
648 | * print out cpufreq information | |
1da177e4 LT |
649 | * |
650 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
651 | * "unsigned int". | |
652 | */ | |
653 | ||
32ee8c3e DJ |
654 | #define show_one(file_name, object) \ |
655 | static ssize_t show_##file_name \ | |
905d77cd | 656 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 657 | { \ |
29464f28 | 658 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
659 | } |
660 | ||
661 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
662 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 663 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
664 | show_one(scaling_min_freq, min); |
665 | show_one(scaling_max_freq, max); | |
c034b02e | 666 | |
f8475cef LB |
667 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
668 | { | |
669 | return 0; | |
670 | } | |
671 | ||
09347b29 | 672 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
673 | { |
674 | ssize_t ret; | |
f8475cef | 675 | unsigned int freq; |
c034b02e | 676 | |
f8475cef LB |
677 | freq = arch_freq_get_on_cpu(policy->cpu); |
678 | if (freq) | |
679 | ret = sprintf(buf, "%u\n", freq); | |
680 | else if (cpufreq_driver && cpufreq_driver->setpolicy && | |
681 | cpufreq_driver->get) | |
c034b02e DB |
682 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
683 | else | |
684 | ret = sprintf(buf, "%u\n", policy->cur); | |
685 | return ret; | |
686 | } | |
1da177e4 | 687 | |
037ce839 | 688 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 689 | struct cpufreq_policy *new_policy); |
7970e08b | 690 | |
1da177e4 LT |
691 | /** |
692 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
693 | */ | |
694 | #define store_one(file_name, object) \ | |
695 | static ssize_t store_##file_name \ | |
905d77cd | 696 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 697 | { \ |
619c144c | 698 | int ret, temp; \ |
1da177e4 LT |
699 | struct cpufreq_policy new_policy; \ |
700 | \ | |
8fa5b631 | 701 | memcpy(&new_policy, policy, sizeof(*policy)); \ |
1da177e4 | 702 | \ |
29464f28 | 703 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
704 | if (ret != 1) \ |
705 | return -EINVAL; \ | |
706 | \ | |
619c144c | 707 | temp = new_policy.object; \ |
037ce839 | 708 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
709 | if (!ret) \ |
710 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
711 | \ |
712 | return ret ? ret : count; \ | |
713 | } | |
714 | ||
29464f28 DJ |
715 | store_one(scaling_min_freq, min); |
716 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
717 | |
718 | /** | |
719 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
720 | */ | |
905d77cd DJ |
721 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
722 | char *buf) | |
1da177e4 | 723 | { |
d92d50a4 | 724 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
725 | |
726 | if (cur_freq) | |
727 | return sprintf(buf, "%u\n", cur_freq); | |
728 | ||
729 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
730 | } |
731 | ||
1da177e4 LT |
732 | /** |
733 | * show_scaling_governor - show the current policy for the specified CPU | |
734 | */ | |
905d77cd | 735 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 736 | { |
29464f28 | 737 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
738 | return sprintf(buf, "powersave\n"); |
739 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
740 | return sprintf(buf, "performance\n"); | |
741 | else if (policy->governor) | |
4b972f0b | 742 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 743 | policy->governor->name); |
1da177e4 LT |
744 | return -EINVAL; |
745 | } | |
746 | ||
1da177e4 LT |
747 | /** |
748 | * store_scaling_governor - store policy for the specified CPU | |
749 | */ | |
905d77cd DJ |
750 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
751 | const char *buf, size_t count) | |
1da177e4 | 752 | { |
5136fa56 | 753 | int ret; |
1da177e4 LT |
754 | char str_governor[16]; |
755 | struct cpufreq_policy new_policy; | |
756 | ||
8fa5b631 | 757 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 758 | |
29464f28 | 759 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
760 | if (ret != 1) |
761 | return -EINVAL; | |
762 | ||
e08f5f5b GS |
763 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
764 | &new_policy.governor)) | |
1da177e4 LT |
765 | return -EINVAL; |
766 | ||
037ce839 | 767 | ret = cpufreq_set_policy(policy, &new_policy); |
88dc4384 | 768 | return ret ? ret : count; |
1da177e4 LT |
769 | } |
770 | ||
771 | /** | |
772 | * show_scaling_driver - show the cpufreq driver currently loaded | |
773 | */ | |
905d77cd | 774 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 775 | { |
1c3d85dd | 776 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
777 | } |
778 | ||
779 | /** | |
780 | * show_scaling_available_governors - show the available CPUfreq governors | |
781 | */ | |
905d77cd DJ |
782 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
783 | char *buf) | |
1da177e4 LT |
784 | { |
785 | ssize_t i = 0; | |
786 | struct cpufreq_governor *t; | |
787 | ||
9c0ebcf7 | 788 | if (!has_target()) { |
1da177e4 LT |
789 | i += sprintf(buf, "performance powersave"); |
790 | goto out; | |
791 | } | |
792 | ||
f7b27061 | 793 | for_each_governor(t) { |
29464f28 DJ |
794 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
795 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 796 | goto out; |
4b972f0b | 797 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 798 | } |
7d5e350f | 799 | out: |
1da177e4 LT |
800 | i += sprintf(&buf[i], "\n"); |
801 | return i; | |
802 | } | |
e8628dd0 | 803 | |
f4fd3797 | 804 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
805 | { |
806 | ssize_t i = 0; | |
807 | unsigned int cpu; | |
808 | ||
835481d9 | 809 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
810 | if (i) |
811 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
812 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
813 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 814 | break; |
1da177e4 LT |
815 | } |
816 | i += sprintf(&buf[i], "\n"); | |
817 | return i; | |
818 | } | |
f4fd3797 | 819 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 820 | |
e8628dd0 DW |
821 | /** |
822 | * show_related_cpus - show the CPUs affected by each transition even if | |
823 | * hw coordination is in use | |
824 | */ | |
825 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
826 | { | |
f4fd3797 | 827 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
828 | } |
829 | ||
830 | /** | |
831 | * show_affected_cpus - show the CPUs affected by each transition | |
832 | */ | |
833 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
834 | { | |
f4fd3797 | 835 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
836 | } |
837 | ||
9e76988e | 838 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 839 | const char *buf, size_t count) |
9e76988e VP |
840 | { |
841 | unsigned int freq = 0; | |
842 | unsigned int ret; | |
843 | ||
879000f9 | 844 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
845 | return -EINVAL; |
846 | ||
847 | ret = sscanf(buf, "%u", &freq); | |
848 | if (ret != 1) | |
849 | return -EINVAL; | |
850 | ||
851 | policy->governor->store_setspeed(policy, freq); | |
852 | ||
853 | return count; | |
854 | } | |
855 | ||
856 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
857 | { | |
879000f9 | 858 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
859 | return sprintf(buf, "<unsupported>\n"); |
860 | ||
861 | return policy->governor->show_setspeed(policy, buf); | |
862 | } | |
1da177e4 | 863 | |
e2f74f35 | 864 | /** |
8bf1ac72 | 865 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
866 | */ |
867 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
868 | { | |
869 | unsigned int limit; | |
870 | int ret; | |
1c3d85dd RW |
871 | if (cpufreq_driver->bios_limit) { |
872 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
873 | if (!ret) |
874 | return sprintf(buf, "%u\n", limit); | |
875 | } | |
876 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
877 | } | |
878 | ||
6dad2a29 BP |
879 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
880 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
881 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
882 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
883 | cpufreq_freq_attr_ro(scaling_available_governors); | |
884 | cpufreq_freq_attr_ro(scaling_driver); | |
885 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
886 | cpufreq_freq_attr_ro(bios_limit); | |
887 | cpufreq_freq_attr_ro(related_cpus); | |
888 | cpufreq_freq_attr_ro(affected_cpus); | |
889 | cpufreq_freq_attr_rw(scaling_min_freq); | |
890 | cpufreq_freq_attr_rw(scaling_max_freq); | |
891 | cpufreq_freq_attr_rw(scaling_governor); | |
892 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 893 | |
905d77cd | 894 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
895 | &cpuinfo_min_freq.attr, |
896 | &cpuinfo_max_freq.attr, | |
ed129784 | 897 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
898 | &scaling_min_freq.attr, |
899 | &scaling_max_freq.attr, | |
900 | &affected_cpus.attr, | |
e8628dd0 | 901 | &related_cpus.attr, |
1da177e4 LT |
902 | &scaling_governor.attr, |
903 | &scaling_driver.attr, | |
904 | &scaling_available_governors.attr, | |
9e76988e | 905 | &scaling_setspeed.attr, |
1da177e4 LT |
906 | NULL |
907 | }; | |
908 | ||
29464f28 DJ |
909 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
910 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 911 | |
29464f28 | 912 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 913 | { |
905d77cd DJ |
914 | struct cpufreq_policy *policy = to_policy(kobj); |
915 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 916 | ssize_t ret; |
6eed9404 | 917 | |
ad7722da | 918 | down_read(&policy->rwsem); |
6541aef0 | 919 | ret = fattr->show(policy, buf); |
ad7722da | 920 | up_read(&policy->rwsem); |
1b750e3b | 921 | |
1da177e4 LT |
922 | return ret; |
923 | } | |
924 | ||
905d77cd DJ |
925 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
926 | const char *buf, size_t count) | |
1da177e4 | 927 | { |
905d77cd DJ |
928 | struct cpufreq_policy *policy = to_policy(kobj); |
929 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 930 | ssize_t ret = -EINVAL; |
6eed9404 | 931 | |
a92551e4 | 932 | cpus_read_lock(); |
4f750c93 | 933 | |
6541aef0 RW |
934 | if (cpu_online(policy->cpu)) { |
935 | down_write(&policy->rwsem); | |
e08f5f5b | 936 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
937 | up_write(&policy->rwsem); |
938 | } | |
e08f5f5b | 939 | |
a92551e4 | 940 | cpus_read_unlock(); |
4f750c93 | 941 | |
1da177e4 LT |
942 | return ret; |
943 | } | |
944 | ||
905d77cd | 945 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 946 | { |
905d77cd | 947 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 948 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
949 | complete(&policy->kobj_unregister); |
950 | } | |
951 | ||
52cf25d0 | 952 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
953 | .show = show, |
954 | .store = store, | |
955 | }; | |
956 | ||
957 | static struct kobj_type ktype_cpufreq = { | |
958 | .sysfs_ops = &sysfs_ops, | |
959 | .default_attrs = default_attrs, | |
960 | .release = cpufreq_sysfs_release, | |
961 | }; | |
962 | ||
2f0ba790 | 963 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) |
87549141 | 964 | { |
2f0ba790 RW |
965 | struct device *dev = get_cpu_device(cpu); |
966 | ||
967 | if (!dev) | |
968 | return; | |
969 | ||
970 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
971 | return; | |
972 | ||
26619804 | 973 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
974 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
975 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
976 | } |
977 | ||
26619804 VK |
978 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
979 | struct device *dev) | |
87549141 | 980 | { |
26619804 VK |
981 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
982 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
983 | } |
984 | ||
d9612a49 | 985 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
986 | { |
987 | struct freq_attr **drv_attr; | |
909a694e | 988 | int ret = 0; |
909a694e | 989 | |
909a694e | 990 | /* set up files for this cpu device */ |
1c3d85dd | 991 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 992 | while (drv_attr && *drv_attr) { |
909a694e DJ |
993 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
994 | if (ret) | |
6d4e81ed | 995 | return ret; |
909a694e DJ |
996 | drv_attr++; |
997 | } | |
1c3d85dd | 998 | if (cpufreq_driver->get) { |
909a694e DJ |
999 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1000 | if (ret) | |
6d4e81ed | 1001 | return ret; |
909a694e | 1002 | } |
c034b02e DB |
1003 | |
1004 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1005 | if (ret) | |
6d4e81ed | 1006 | return ret; |
c034b02e | 1007 | |
1c3d85dd | 1008 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1009 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1010 | if (ret) | |
6d4e81ed | 1011 | return ret; |
e2f74f35 | 1012 | } |
909a694e | 1013 | |
26619804 | 1014 | return 0; |
e18f1682 SB |
1015 | } |
1016 | ||
de1df26b RW |
1017 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
1018 | { | |
1019 | return NULL; | |
1020 | } | |
1021 | ||
7f0fa40f | 1022 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1023 | { |
6e2c89d1 | 1024 | struct cpufreq_governor *gov = NULL; |
e18f1682 | 1025 | struct cpufreq_policy new_policy; |
e18f1682 | 1026 | |
d5b73cd8 | 1027 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 1028 | |
6e2c89d1 | 1029 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 1030 | gov = find_governor(policy->last_governor); |
de1df26b | 1031 | if (gov) { |
6e2c89d1 | 1032 | pr_debug("Restoring governor %s for cpu %d\n", |
1033 | policy->governor->name, policy->cpu); | |
de1df26b RW |
1034 | } else { |
1035 | gov = cpufreq_default_governor(); | |
1036 | if (!gov) | |
1037 | return -ENODATA; | |
1038 | } | |
6e2c89d1 | 1039 | |
1040 | new_policy.governor = gov; | |
1041 | ||
69030dd1 SP |
1042 | /* Use the default policy if there is no last_policy. */ |
1043 | if (cpufreq_driver->setpolicy) { | |
1044 | if (policy->last_policy) | |
1045 | new_policy.policy = policy->last_policy; | |
1046 | else | |
1047 | cpufreq_parse_governor(gov->name, &new_policy.policy, | |
1048 | NULL); | |
1049 | } | |
ecf7e461 | 1050 | /* set default policy */ |
7f0fa40f | 1051 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
1052 | } |
1053 | ||
d9612a49 | 1054 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1055 | { |
9c0ebcf7 | 1056 | int ret = 0; |
fcf80582 | 1057 | |
bb29ae15 VK |
1058 | /* Has this CPU been taken care of already? */ |
1059 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1060 | return 0; | |
1061 | ||
49f18560 | 1062 | down_write(&policy->rwsem); |
45482c70 RW |
1063 | if (has_target()) |
1064 | cpufreq_stop_governor(policy); | |
fcf80582 | 1065 | |
fcf80582 | 1066 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1067 | |
9c0ebcf7 | 1068 | if (has_target()) { |
0a300767 | 1069 | ret = cpufreq_start_governor(policy); |
49f18560 | 1070 | if (ret) |
3de9bdeb | 1071 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1072 | } |
49f18560 VK |
1073 | up_write(&policy->rwsem); |
1074 | return ret; | |
fcf80582 | 1075 | } |
1da177e4 | 1076 | |
11eb69b9 VK |
1077 | static void handle_update(struct work_struct *work) |
1078 | { | |
1079 | struct cpufreq_policy *policy = | |
1080 | container_of(work, struct cpufreq_policy, update); | |
1081 | unsigned int cpu = policy->cpu; | |
1082 | pr_debug("handle_update for cpu %u called\n", cpu); | |
1083 | cpufreq_update_policy(cpu); | |
fcf80582 | 1084 | } |
1da177e4 | 1085 | |
a34e63b1 | 1086 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1087 | { |
1088 | struct cpufreq_policy *policy; | |
edd4a893 | 1089 | int ret; |
e9698cc5 SB |
1090 | |
1091 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); | |
1092 | if (!policy) | |
1093 | return NULL; | |
1094 | ||
1095 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1096 | goto err_free_policy; | |
1097 | ||
1098 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1099 | goto err_free_cpumask; | |
1100 | ||
559ed407 RW |
1101 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1102 | goto err_free_rcpumask; | |
1103 | ||
edd4a893 VK |
1104 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1105 | cpufreq_global_kobject, "policy%u", cpu); | |
1106 | if (ret) { | |
1107 | pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); | |
1108 | goto err_free_real_cpus; | |
1109 | } | |
1110 | ||
c88a1f8b | 1111 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1112 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1113 | spin_lock_init(&policy->transition_lock); |
1114 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1115 | init_completion(&policy->kobj_unregister); |
1116 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1117 | |
a34e63b1 | 1118 | policy->cpu = cpu; |
e9698cc5 SB |
1119 | return policy; |
1120 | ||
edd4a893 VK |
1121 | err_free_real_cpus: |
1122 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1123 | err_free_rcpumask: |
1124 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1125 | err_free_cpumask: |
1126 | free_cpumask_var(policy->cpus); | |
1127 | err_free_policy: | |
1128 | kfree(policy); | |
1129 | ||
1130 | return NULL; | |
1131 | } | |
1132 | ||
f9f41e3e | 1133 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) |
42f921a6 VK |
1134 | { |
1135 | struct kobject *kobj; | |
1136 | struct completion *cmp; | |
1137 | ||
87549141 | 1138 | down_write(&policy->rwsem); |
1aefc75b | 1139 | cpufreq_stats_free_table(policy); |
42f921a6 VK |
1140 | kobj = &policy->kobj; |
1141 | cmp = &policy->kobj_unregister; | |
87549141 | 1142 | up_write(&policy->rwsem); |
42f921a6 VK |
1143 | kobject_put(kobj); |
1144 | ||
1145 | /* | |
1146 | * We need to make sure that the underlying kobj is | |
1147 | * actually not referenced anymore by anybody before we | |
1148 | * proceed with unloading. | |
1149 | */ | |
1150 | pr_debug("waiting for dropping of refcount\n"); | |
1151 | wait_for_completion(cmp); | |
1152 | pr_debug("wait complete\n"); | |
1153 | } | |
1154 | ||
f9f41e3e | 1155 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1156 | { |
988bed09 VK |
1157 | unsigned long flags; |
1158 | int cpu; | |
1159 | ||
1160 | /* Remove policy from list */ | |
1161 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1162 | list_del(&policy->policy_list); | |
1163 | ||
1164 | for_each_cpu(cpu, policy->related_cpus) | |
1165 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1166 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1167 | ||
f9f41e3e | 1168 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1169 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1170 | free_cpumask_var(policy->related_cpus); |
1171 | free_cpumask_var(policy->cpus); | |
1172 | kfree(policy); | |
1173 | } | |
1174 | ||
0b275352 | 1175 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1176 | { |
7f0c020a | 1177 | struct cpufreq_policy *policy; |
194d99c7 | 1178 | bool new_policy; |
1da177e4 | 1179 | unsigned long flags; |
0b275352 RW |
1180 | unsigned int j; |
1181 | int ret; | |
87549141 | 1182 | |
0b275352 | 1183 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1184 | |
bb29ae15 | 1185 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1186 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1187 | if (policy) { |
9104bb26 | 1188 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1189 | if (!policy_is_inactive(policy)) |
d9612a49 | 1190 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1191 | |
11ce707e | 1192 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1193 | new_policy = false; |
11ce707e RW |
1194 | down_write(&policy->rwsem); |
1195 | policy->cpu = cpu; | |
1196 | policy->governor = NULL; | |
1197 | up_write(&policy->rwsem); | |
1198 | } else { | |
194d99c7 | 1199 | new_policy = true; |
a34e63b1 | 1200 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1201 | if (!policy) |
d4d854d6 | 1202 | return -ENOMEM; |
72368d12 | 1203 | } |
0d66b91e | 1204 | |
835481d9 | 1205 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1206 | |
1da177e4 LT |
1207 | /* call driver. From then on the cpufreq must be able |
1208 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1209 | */ | |
1c3d85dd | 1210 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1211 | if (ret) { |
2d06d8c4 | 1212 | pr_debug("initialization failed\n"); |
8101f997 | 1213 | goto out_free_policy; |
1da177e4 | 1214 | } |
643ae6e8 | 1215 | |
6d4e81ed TV |
1216 | down_write(&policy->rwsem); |
1217 | ||
194d99c7 | 1218 | if (new_policy) { |
4d1f3a5b | 1219 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1220 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1221 | } |
559ed407 | 1222 | |
5a7e56a5 VK |
1223 | /* |
1224 | * affected cpus must always be the one, which are online. We aren't | |
1225 | * managing offline cpus here. | |
1226 | */ | |
1227 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1228 | ||
194d99c7 | 1229 | if (new_policy) { |
5a7e56a5 VK |
1230 | policy->user_policy.min = policy->min; |
1231 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1232 | |
2f0ba790 | 1233 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1234 | per_cpu(cpufreq_cpu_data, j) = policy; |
2f0ba790 RW |
1235 | add_cpu_dev_symlink(policy, j); |
1236 | } | |
ff010472 VK |
1237 | } else { |
1238 | policy->min = policy->user_policy.min; | |
1239 | policy->max = policy->user_policy.max; | |
988bed09 | 1240 | } |
652ed95d | 1241 | |
2ed99e39 | 1242 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1243 | policy->cur = cpufreq_driver->get(policy->cpu); |
1244 | if (!policy->cur) { | |
1245 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1246 | goto out_exit_policy; |
da60ce9f VK |
1247 | } |
1248 | } | |
1249 | ||
d3916691 VK |
1250 | /* |
1251 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1252 | * frequency table present with cpufreq core. In such cases CPU might be | |
1253 | * unstable if it has to run on that frequency for long duration of time | |
1254 | * and so its better to set it to a frequency which is specified in | |
1255 | * freq-table. This also makes cpufreq stats inconsistent as | |
1256 | * cpufreq-stats would fail to register because current frequency of CPU | |
1257 | * isn't found in freq-table. | |
1258 | * | |
1259 | * Because we don't want this change to effect boot process badly, we go | |
1260 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1261 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1262 | * is initialized to zero). | |
1263 | * | |
1264 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1265 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1266 | * equal to target-freq. | |
1267 | */ | |
1268 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1269 | && has_target()) { | |
1270 | /* Are we running at unknown frequency ? */ | |
1271 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1272 | if (ret == -EINVAL) { | |
1273 | /* Warn user and fix it */ | |
1274 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1275 | __func__, policy->cpu, policy->cur); | |
1276 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1277 | CPUFREQ_RELATION_L); | |
1278 | ||
1279 | /* | |
1280 | * Reaching here after boot in a few seconds may not | |
1281 | * mean that system will remain stable at "unknown" | |
1282 | * frequency for longer duration. Hence, a BUG_ON(). | |
1283 | */ | |
1284 | BUG_ON(ret); | |
1285 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1286 | __func__, policy->cpu, policy->cur); | |
1287 | } | |
1288 | } | |
1289 | ||
194d99c7 | 1290 | if (new_policy) { |
d9612a49 | 1291 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1292 | if (ret) |
8101f997 | 1293 | goto out_exit_policy; |
1aefc75b RW |
1294 | |
1295 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1296 | |
988bed09 VK |
1297 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1298 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1299 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1300 | } | |
9515f4d6 | 1301 | |
7f0fa40f VK |
1302 | ret = cpufreq_init_policy(policy); |
1303 | if (ret) { | |
1304 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1305 | __func__, cpu, ret); | |
194d99c7 RW |
1306 | /* cpufreq_policy_free() will notify based on this */ |
1307 | new_policy = false; | |
1308 | goto out_exit_policy; | |
08fd8c1c | 1309 | } |
e18f1682 | 1310 | |
4e97b631 | 1311 | up_write(&policy->rwsem); |
08fd8c1c | 1312 | |
038c5b3e | 1313 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1314 | |
7c45cf31 VK |
1315 | /* Callback for handling stuff after policy is ready */ |
1316 | if (cpufreq_driver->ready) | |
1317 | cpufreq_driver->ready(policy); | |
1318 | ||
2d06d8c4 | 1319 | pr_debug("initialization complete\n"); |
87c32271 | 1320 | |
1da177e4 LT |
1321 | return 0; |
1322 | ||
8101f997 | 1323 | out_exit_policy: |
7106e02b PB |
1324 | up_write(&policy->rwsem); |
1325 | ||
da60ce9f VK |
1326 | if (cpufreq_driver->exit) |
1327 | cpufreq_driver->exit(policy); | |
2f0ba790 RW |
1328 | |
1329 | for_each_cpu(j, policy->real_cpus) | |
1330 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1331 | ||
8101f997 | 1332 | out_free_policy: |
f9f41e3e | 1333 | cpufreq_policy_free(policy); |
1da177e4 LT |
1334 | return ret; |
1335 | } | |
1336 | ||
0b275352 RW |
1337 | /** |
1338 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1339 | * @dev: CPU device. | |
1340 | * @sif: Subsystem interface structure pointer (not used) | |
1341 | */ | |
1342 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1343 | { | |
a794d613 | 1344 | struct cpufreq_policy *policy; |
0b275352 | 1345 | unsigned cpu = dev->id; |
26619804 | 1346 | int ret; |
0b275352 RW |
1347 | |
1348 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1349 | ||
26619804 VK |
1350 | if (cpu_online(cpu)) { |
1351 | ret = cpufreq_online(cpu); | |
1352 | if (ret) | |
1353 | return ret; | |
1354 | } | |
0b275352 | 1355 | |
26619804 | 1356 | /* Create sysfs link on CPU registration */ |
a794d613 | 1357 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 RW |
1358 | if (policy) |
1359 | add_cpu_dev_symlink(policy, cpu); | |
26619804 | 1360 | |
2f0ba790 | 1361 | return 0; |
1da177e4 LT |
1362 | } |
1363 | ||
27622b06 | 1364 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1365 | { |
3a3e9e06 | 1366 | struct cpufreq_policy *policy; |
69cee714 | 1367 | int ret; |
1da177e4 | 1368 | |
b8eed8af | 1369 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1370 | |
988bed09 | 1371 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1372 | if (!policy) { |
b8eed8af | 1373 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1374 | return 0; |
1da177e4 | 1375 | } |
1da177e4 | 1376 | |
49f18560 | 1377 | down_write(&policy->rwsem); |
45482c70 RW |
1378 | if (has_target()) |
1379 | cpufreq_stop_governor(policy); | |
1da177e4 | 1380 | |
9591becb | 1381 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1382 | |
9591becb VK |
1383 | if (policy_is_inactive(policy)) { |
1384 | if (has_target()) | |
1385 | strncpy(policy->last_governor, policy->governor->name, | |
1386 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1387 | else |
1388 | policy->last_policy = policy->policy; | |
9591becb VK |
1389 | } else if (cpu == policy->cpu) { |
1390 | /* Nominate new CPU */ | |
1391 | policy->cpu = cpumask_any(policy->cpus); | |
1392 | } | |
084f3493 | 1393 | |
9591becb VK |
1394 | /* Start governor again for active policy */ |
1395 | if (!policy_is_inactive(policy)) { | |
1396 | if (has_target()) { | |
0a300767 | 1397 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1398 | if (ret) |
1399 | pr_err("%s: Failed to start governor\n", __func__); | |
1400 | } | |
cedb70af | 1401 | |
49f18560 | 1402 | goto unlock; |
cedb70af SB |
1403 | } |
1404 | ||
69cee714 VK |
1405 | if (cpufreq_driver->stop_cpu) |
1406 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1407 | |
36be3418 RW |
1408 | if (has_target()) |
1409 | cpufreq_exit_governor(policy); | |
1da177e4 | 1410 | |
87549141 VK |
1411 | /* |
1412 | * Perform the ->exit() even during light-weight tear-down, | |
1413 | * since this is a core component, and is essential for the | |
1414 | * subsequent light-weight ->init() to succeed. | |
1415 | */ | |
55582bcc | 1416 | if (cpufreq_driver->exit) { |
87549141 | 1417 | cpufreq_driver->exit(policy); |
55582bcc SP |
1418 | policy->freq_table = NULL; |
1419 | } | |
49f18560 VK |
1420 | |
1421 | unlock: | |
1422 | up_write(&policy->rwsem); | |
27622b06 | 1423 | return 0; |
1da177e4 LT |
1424 | } |
1425 | ||
cedb70af | 1426 | /** |
27a862e9 | 1427 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1428 | * |
1429 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1430 | */ |
71db87ba | 1431 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1432 | { |
8a25a2fd | 1433 | unsigned int cpu = dev->id; |
559ed407 | 1434 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1435 | |
559ed407 | 1436 | if (!policy) |
1af115d6 | 1437 | return; |
87549141 | 1438 | |
69cee714 VK |
1439 | if (cpu_online(cpu)) |
1440 | cpufreq_offline(cpu); | |
87549141 | 1441 | |
559ed407 | 1442 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1443 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1444 | |
f344dae0 | 1445 | if (cpumask_empty(policy->real_cpus)) |
f9f41e3e | 1446 | cpufreq_policy_free(policy); |
5a01f2e8 VP |
1447 | } |
1448 | ||
1da177e4 | 1449 | /** |
bb176f7d VK |
1450 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1451 | * in deep trouble. | |
a1e1dc41 | 1452 | * @policy: policy managing CPUs |
1da177e4 LT |
1453 | * @new_freq: CPU frequency the CPU actually runs at |
1454 | * | |
29464f28 DJ |
1455 | * We adjust to current frequency first, and need to clean up later. |
1456 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1457 | */ |
a1e1dc41 | 1458 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1459 | unsigned int new_freq) |
1da177e4 LT |
1460 | { |
1461 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1462 | |
e837f9b5 | 1463 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1464 | policy->cur, new_freq); |
1da177e4 | 1465 | |
a1e1dc41 | 1466 | freqs.old = policy->cur; |
1da177e4 | 1467 | freqs.new = new_freq; |
b43a7ffb | 1468 | |
8fec051e VK |
1469 | cpufreq_freq_transition_begin(policy, &freqs); |
1470 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1471 | } |
1472 | ||
32ee8c3e | 1473 | /** |
4ab70df4 | 1474 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1475 | * @cpu: CPU number |
1476 | * | |
1477 | * This is the last known freq, without actually getting it from the driver. | |
1478 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1479 | */ | |
1480 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1481 | { | |
9e21ba8b | 1482 | struct cpufreq_policy *policy; |
e08f5f5b | 1483 | unsigned int ret_freq = 0; |
c75361c0 | 1484 | unsigned long flags; |
95235ca2 | 1485 | |
c75361c0 RC |
1486 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1487 | ||
1488 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1489 | ret_freq = cpufreq_driver->get(cpu); | |
1490 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1491 | return ret_freq; | |
1492 | } | |
1493 | ||
1494 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1495 | |
1496 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1497 | if (policy) { |
e08f5f5b | 1498 | ret_freq = policy->cur; |
95235ca2 VP |
1499 | cpufreq_cpu_put(policy); |
1500 | } | |
1501 | ||
4d34a67d | 1502 | return ret_freq; |
95235ca2 VP |
1503 | } |
1504 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1505 | ||
3d737108 JB |
1506 | /** |
1507 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1508 | * @cpu: CPU number | |
1509 | * | |
1510 | * Just return the max possible frequency for a given CPU. | |
1511 | */ | |
1512 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1513 | { | |
1514 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1515 | unsigned int ret_freq = 0; | |
1516 | ||
1517 | if (policy) { | |
1518 | ret_freq = policy->max; | |
1519 | cpufreq_cpu_put(policy); | |
1520 | } | |
1521 | ||
1522 | return ret_freq; | |
1523 | } | |
1524 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1525 | ||
d92d50a4 | 1526 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1527 | { |
e08f5f5b | 1528 | unsigned int ret_freq = 0; |
5800043b | 1529 | |
1c3d85dd | 1530 | if (!cpufreq_driver->get) |
4d34a67d | 1531 | return ret_freq; |
1da177e4 | 1532 | |
d92d50a4 | 1533 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1534 | |
b7898fda RW |
1535 | /* |
1536 | * Updating inactive policies is invalid, so avoid doing that. Also | |
1537 | * if fast frequency switching is used with the given policy, the check | |
1538 | * against policy->cur is pointless, so skip it in that case too. | |
1539 | */ | |
1540 | if (unlikely(policy_is_inactive(policy)) || policy->fast_switch_enabled) | |
11e584cf VK |
1541 | return ret_freq; |
1542 | ||
e08f5f5b | 1543 | if (ret_freq && policy->cur && |
1c3d85dd | 1544 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1545 | /* verify no discrepancy between actual and |
1546 | saved value exists */ | |
1547 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1548 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1549 | schedule_work(&policy->update); |
1550 | } | |
1551 | } | |
1552 | ||
4d34a67d | 1553 | return ret_freq; |
5a01f2e8 | 1554 | } |
1da177e4 | 1555 | |
5a01f2e8 VP |
1556 | /** |
1557 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1558 | * @cpu: CPU number | |
1559 | * | |
1560 | * Get the CPU current (static) CPU frequency | |
1561 | */ | |
1562 | unsigned int cpufreq_get(unsigned int cpu) | |
1563 | { | |
999976e0 | 1564 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1565 | unsigned int ret_freq = 0; |
5a01f2e8 | 1566 | |
999976e0 AP |
1567 | if (policy) { |
1568 | down_read(&policy->rwsem); | |
182e36af RW |
1569 | |
1570 | if (!policy_is_inactive(policy)) | |
1571 | ret_freq = __cpufreq_get(policy); | |
1572 | ||
999976e0 | 1573 | up_read(&policy->rwsem); |
5a01f2e8 | 1574 | |
999976e0 AP |
1575 | cpufreq_cpu_put(policy); |
1576 | } | |
6eed9404 | 1577 | |
4d34a67d | 1578 | return ret_freq; |
1da177e4 LT |
1579 | } |
1580 | EXPORT_SYMBOL(cpufreq_get); | |
1581 | ||
999f5729 RW |
1582 | static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy) |
1583 | { | |
1584 | unsigned int new_freq; | |
1585 | ||
1586 | new_freq = cpufreq_driver->get(policy->cpu); | |
1587 | if (!new_freq) | |
1588 | return 0; | |
1589 | ||
1590 | if (!policy->cur) { | |
1591 | pr_debug("cpufreq: Driver did not initialize current freq\n"); | |
1592 | policy->cur = new_freq; | |
1593 | } else if (policy->cur != new_freq && has_target()) { | |
1594 | cpufreq_out_of_sync(policy, new_freq); | |
1595 | } | |
1596 | ||
1597 | return new_freq; | |
1598 | } | |
1599 | ||
8a25a2fd KS |
1600 | static struct subsys_interface cpufreq_interface = { |
1601 | .name = "cpufreq", | |
1602 | .subsys = &cpu_subsys, | |
1603 | .add_dev = cpufreq_add_dev, | |
1604 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1605 | }; |
1606 | ||
e28867ea VK |
1607 | /* |
1608 | * In case platform wants some specific frequency to be configured | |
1609 | * during suspend.. | |
1610 | */ | |
1611 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1612 | { | |
1613 | int ret; | |
1614 | ||
1615 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1616 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1617 | return 0; | |
e28867ea VK |
1618 | } |
1619 | ||
1620 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1621 | policy->suspend_freq); | |
1622 | ||
1623 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1624 | CPUFREQ_RELATION_H); | |
1625 | if (ret) | |
1626 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1627 | __func__, policy->suspend_freq, ret); | |
1628 | ||
1629 | return ret; | |
1630 | } | |
1631 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1632 | ||
42d4dc3f | 1633 | /** |
2f0aea93 | 1634 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1635 | * |
2f0aea93 VK |
1636 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1637 | * as some platforms can't change frequency after this point in suspend cycle. | |
1638 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1639 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1640 | */ |
2f0aea93 | 1641 | void cpufreq_suspend(void) |
42d4dc3f | 1642 | { |
3a3e9e06 | 1643 | struct cpufreq_policy *policy; |
42d4dc3f | 1644 | |
2f0aea93 VK |
1645 | if (!cpufreq_driver) |
1646 | return; | |
42d4dc3f | 1647 | |
ba41e1bc | 1648 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1649 | goto suspend; |
42d4dc3f | 1650 | |
2f0aea93 VK |
1651 | pr_debug("%s: Suspending Governors\n", __func__); |
1652 | ||
f963735a | 1653 | for_each_active_policy(policy) { |
ba41e1bc RW |
1654 | if (has_target()) { |
1655 | down_write(&policy->rwsem); | |
45482c70 | 1656 | cpufreq_stop_governor(policy); |
ba41e1bc | 1657 | up_write(&policy->rwsem); |
ba41e1bc RW |
1658 | } |
1659 | ||
1660 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
2f0aea93 VK |
1661 | pr_err("%s: Failed to suspend driver: %p\n", __func__, |
1662 | policy); | |
42d4dc3f | 1663 | } |
b1b12bab VK |
1664 | |
1665 | suspend: | |
1666 | cpufreq_suspended = true; | |
42d4dc3f BH |
1667 | } |
1668 | ||
1da177e4 | 1669 | /** |
2f0aea93 | 1670 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1671 | * |
2f0aea93 VK |
1672 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1673 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1674 | */ |
2f0aea93 | 1675 | void cpufreq_resume(void) |
1da177e4 | 1676 | { |
3a3e9e06 | 1677 | struct cpufreq_policy *policy; |
49f18560 | 1678 | int ret; |
1da177e4 | 1679 | |
2f0aea93 VK |
1680 | if (!cpufreq_driver) |
1681 | return; | |
1da177e4 | 1682 | |
8e30444e LT |
1683 | cpufreq_suspended = false; |
1684 | ||
ba41e1bc | 1685 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1686 | return; |
1da177e4 | 1687 | |
2f0aea93 | 1688 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1689 | |
f963735a | 1690 | for_each_active_policy(policy) { |
49f18560 | 1691 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1692 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1693 | policy); | |
ba41e1bc | 1694 | } else if (has_target()) { |
49f18560 | 1695 | down_write(&policy->rwsem); |
0a300767 | 1696 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1697 | up_write(&policy->rwsem); |
1698 | ||
1699 | if (ret) | |
1700 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1701 | __func__, policy); | |
1702 | } | |
2f0aea93 VK |
1703 | } |
1704 | } | |
1da177e4 | 1705 | |
9d95046e BP |
1706 | /** |
1707 | * cpufreq_get_current_driver - return current driver's name | |
1708 | * | |
1709 | * Return the name string of the currently loaded cpufreq driver | |
1710 | * or NULL, if none. | |
1711 | */ | |
1712 | const char *cpufreq_get_current_driver(void) | |
1713 | { | |
1c3d85dd RW |
1714 | if (cpufreq_driver) |
1715 | return cpufreq_driver->name; | |
1716 | ||
1717 | return NULL; | |
9d95046e BP |
1718 | } |
1719 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1720 | |
51315cdf TP |
1721 | /** |
1722 | * cpufreq_get_driver_data - return current driver data | |
1723 | * | |
1724 | * Return the private data of the currently loaded cpufreq | |
1725 | * driver, or NULL if no cpufreq driver is loaded. | |
1726 | */ | |
1727 | void *cpufreq_get_driver_data(void) | |
1728 | { | |
1729 | if (cpufreq_driver) | |
1730 | return cpufreq_driver->driver_data; | |
1731 | ||
1732 | return NULL; | |
1733 | } | |
1734 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1735 | ||
1da177e4 LT |
1736 | /********************************************************************* |
1737 | * NOTIFIER LISTS INTERFACE * | |
1738 | *********************************************************************/ | |
1739 | ||
1740 | /** | |
1741 | * cpufreq_register_notifier - register a driver with cpufreq | |
1742 | * @nb: notifier function to register | |
1743 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1744 | * | |
32ee8c3e | 1745 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1746 | * are notified about clock rate changes (once before and once after |
1747 | * the transition), or a list of drivers that are notified about | |
1748 | * changes in cpufreq policy. | |
1749 | * | |
1750 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1751 | * blocking_notifier_chain_register. |
1da177e4 LT |
1752 | */ |
1753 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1754 | { | |
1755 | int ret; | |
1756 | ||
d5aaffa9 DB |
1757 | if (cpufreq_disabled()) |
1758 | return -EINVAL; | |
1759 | ||
74212ca4 CEB |
1760 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1761 | ||
1da177e4 LT |
1762 | switch (list) { |
1763 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1764 | mutex_lock(&cpufreq_fast_switch_lock); |
1765 | ||
1766 | if (cpufreq_fast_switch_count > 0) { | |
1767 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1768 | return -EBUSY; | |
1769 | } | |
b4dfdbb3 | 1770 | ret = srcu_notifier_chain_register( |
e041c683 | 1771 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1772 | if (!ret) |
1773 | cpufreq_fast_switch_count--; | |
1774 | ||
1775 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1776 | break; |
1777 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1778 | ret = blocking_notifier_chain_register( |
1779 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1780 | break; |
1781 | default: | |
1782 | ret = -EINVAL; | |
1783 | } | |
1da177e4 LT |
1784 | |
1785 | return ret; | |
1786 | } | |
1787 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1788 | ||
1da177e4 LT |
1789 | /** |
1790 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1791 | * @nb: notifier block to be unregistered | |
bb176f7d | 1792 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1793 | * |
1794 | * Remove a driver from the CPU frequency notifier list. | |
1795 | * | |
1796 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1797 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1798 | */ |
1799 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1800 | { | |
1801 | int ret; | |
1802 | ||
d5aaffa9 DB |
1803 | if (cpufreq_disabled()) |
1804 | return -EINVAL; | |
1805 | ||
1da177e4 LT |
1806 | switch (list) { |
1807 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1808 | mutex_lock(&cpufreq_fast_switch_lock); |
1809 | ||
b4dfdbb3 | 1810 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1811 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1812 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
1813 | cpufreq_fast_switch_count++; | |
1814 | ||
1815 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1816 | break; |
1817 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1818 | ret = blocking_notifier_chain_unregister( |
1819 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1820 | break; |
1821 | default: | |
1822 | ret = -EINVAL; | |
1823 | } | |
1da177e4 LT |
1824 | |
1825 | return ret; | |
1826 | } | |
1827 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1828 | ||
1829 | ||
1830 | /********************************************************************* | |
1831 | * GOVERNORS * | |
1832 | *********************************************************************/ | |
1833 | ||
b7898fda RW |
1834 | /** |
1835 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
1836 | * @policy: cpufreq policy to switch the frequency for. | |
1837 | * @target_freq: New frequency to set (may be approximate). | |
1838 | * | |
1839 | * Carry out a fast frequency switch without sleeping. | |
1840 | * | |
1841 | * The driver's ->fast_switch() callback invoked by this function must be | |
1842 | * suitable for being called from within RCU-sched read-side critical sections | |
1843 | * and it is expected to select the minimum available frequency greater than or | |
1844 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
1845 | * | |
1846 | * This function must not be called if policy->fast_switch_enabled is unset. | |
1847 | * | |
1848 | * Governors calling this function must guarantee that it will never be invoked | |
1849 | * twice in parallel for the same policy and that it will never be called in | |
1850 | * parallel with either ->target() or ->target_index() for the same policy. | |
1851 | * | |
209887e6 VK |
1852 | * Returns the actual frequency set for the CPU. |
1853 | * | |
1854 | * If 0 is returned by the driver's ->fast_switch() callback to indicate an | |
1855 | * error condition, the hardware configuration must be preserved. | |
b7898fda RW |
1856 | */ |
1857 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
1858 | unsigned int target_freq) | |
1859 | { | |
b9af6948 | 1860 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
b7898fda RW |
1861 | |
1862 | return cpufreq_driver->fast_switch(policy, target_freq); | |
1863 | } | |
1864 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
1865 | ||
1c03a2d0 VK |
1866 | /* Must set freqs->new to intermediate frequency */ |
1867 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1868 | struct cpufreq_freqs *freqs, int index) | |
1869 | { | |
1870 | int ret; | |
1871 | ||
1872 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1873 | ||
1874 | /* We don't need to switch to intermediate freq */ | |
1875 | if (!freqs->new) | |
1876 | return 0; | |
1877 | ||
1878 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1879 | __func__, policy->cpu, freqs->old, freqs->new); | |
1880 | ||
1881 | cpufreq_freq_transition_begin(policy, freqs); | |
1882 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1883 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1884 | ||
1885 | if (ret) | |
1886 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1887 | __func__, ret); | |
1888 | ||
1889 | return ret; | |
1890 | } | |
1891 | ||
23727845 | 1892 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 1893 | { |
1c03a2d0 VK |
1894 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1895 | unsigned int intermediate_freq = 0; | |
23727845 | 1896 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
1897 | int retval = -EINVAL; |
1898 | bool notify; | |
1899 | ||
23727845 VK |
1900 | if (newfreq == policy->cur) |
1901 | return 0; | |
1902 | ||
8d65775d | 1903 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 1904 | if (notify) { |
1c03a2d0 VK |
1905 | /* Handle switching to intermediate frequency */ |
1906 | if (cpufreq_driver->get_intermediate) { | |
1907 | retval = __target_intermediate(policy, &freqs, index); | |
1908 | if (retval) | |
1909 | return retval; | |
1910 | ||
1911 | intermediate_freq = freqs.new; | |
1912 | /* Set old freq to intermediate */ | |
1913 | if (intermediate_freq) | |
1914 | freqs.old = freqs.new; | |
1915 | } | |
8d65775d | 1916 | |
23727845 | 1917 | freqs.new = newfreq; |
8d65775d VK |
1918 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1919 | __func__, policy->cpu, freqs.old, freqs.new); | |
1920 | ||
1921 | cpufreq_freq_transition_begin(policy, &freqs); | |
1922 | } | |
1923 | ||
1924 | retval = cpufreq_driver->target_index(policy, index); | |
1925 | if (retval) | |
1926 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1927 | retval); | |
1928 | ||
1c03a2d0 | 1929 | if (notify) { |
8d65775d VK |
1930 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1931 | ||
1c03a2d0 VK |
1932 | /* |
1933 | * Failed after setting to intermediate freq? Driver should have | |
1934 | * reverted back to initial frequency and so should we. Check | |
1935 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1936 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1937 | */ |
1938 | if (unlikely(retval && intermediate_freq)) { | |
1939 | freqs.old = intermediate_freq; | |
1940 | freqs.new = policy->restore_freq; | |
1941 | cpufreq_freq_transition_begin(policy, &freqs); | |
1942 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1943 | } | |
1944 | } | |
1945 | ||
8d65775d VK |
1946 | return retval; |
1947 | } | |
1948 | ||
1da177e4 LT |
1949 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1950 | unsigned int target_freq, | |
1951 | unsigned int relation) | |
1952 | { | |
7249924e | 1953 | unsigned int old_target_freq = target_freq; |
d218ed77 | 1954 | int index; |
c32b6b8e | 1955 | |
a7b422cd KRW |
1956 | if (cpufreq_disabled()) |
1957 | return -ENODEV; | |
1958 | ||
7249924e | 1959 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 1960 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
1961 | |
1962 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1963 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1964 | |
9c0ebcf7 VK |
1965 | /* |
1966 | * This might look like a redundant call as we are checking it again | |
1967 | * after finding index. But it is left intentionally for cases where | |
1968 | * exactly same freq is called again and so we can save on few function | |
1969 | * calls. | |
1970 | */ | |
5a1c0228 VK |
1971 | if (target_freq == policy->cur) |
1972 | return 0; | |
1973 | ||
1c03a2d0 VK |
1974 | /* Save last value to restore later on errors */ |
1975 | policy->restore_freq = policy->cur; | |
1976 | ||
1c3d85dd | 1977 | if (cpufreq_driver->target) |
6019d23a | 1978 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 1979 | |
6019d23a RW |
1980 | if (!cpufreq_driver->target_index) |
1981 | return -EINVAL; | |
9c0ebcf7 | 1982 | |
d218ed77 | 1983 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 1984 | |
23727845 | 1985 | return __target_index(policy, index); |
1da177e4 LT |
1986 | } |
1987 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1988 | ||
1da177e4 LT |
1989 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1990 | unsigned int target_freq, | |
1991 | unsigned int relation) | |
1992 | { | |
f1829e4a | 1993 | int ret = -EINVAL; |
1da177e4 | 1994 | |
ad7722da | 1995 | down_write(&policy->rwsem); |
1da177e4 LT |
1996 | |
1997 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1998 | ||
ad7722da | 1999 | up_write(&policy->rwsem); |
1da177e4 | 2000 | |
1da177e4 LT |
2001 | return ret; |
2002 | } | |
2003 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2004 | ||
de1df26b RW |
2005 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
2006 | { | |
2007 | return NULL; | |
2008 | } | |
2009 | ||
a92604b4 | 2010 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2011 | { |
cc993cab | 2012 | int ret; |
6afde10c | 2013 | |
2f0aea93 VK |
2014 | /* Don't start any governor operations if we are entering suspend */ |
2015 | if (cpufreq_suspended) | |
2016 | return 0; | |
cb57720b EZ |
2017 | /* |
2018 | * Governor might not be initiated here if ACPI _PPC changed | |
2019 | * notification happened, so check it. | |
2020 | */ | |
2021 | if (!policy->governor) | |
2022 | return -EINVAL; | |
2f0aea93 | 2023 | |
ed4676e2 VK |
2024 | /* Platform doesn't want dynamic frequency switching ? */ |
2025 | if (policy->governor->dynamic_switching && | |
fc4c709f | 2026 | cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { |
de1df26b RW |
2027 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2028 | ||
2029 | if (gov) { | |
fe829ed8 | 2030 | pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", |
e837f9b5 | 2031 | policy->governor->name, gov->name); |
6afde10c | 2032 | policy->governor = gov; |
de1df26b RW |
2033 | } else { |
2034 | return -EINVAL; | |
6afde10c | 2035 | } |
1c256245 | 2036 | } |
1da177e4 | 2037 | |
a92604b4 RW |
2038 | if (!try_module_get(policy->governor->owner)) |
2039 | return -EINVAL; | |
95731ebb | 2040 | |
a92604b4 | 2041 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2042 | |
e788892b RW |
2043 | if (policy->governor->init) { |
2044 | ret = policy->governor->init(policy); | |
2045 | if (ret) { | |
36be3418 | 2046 | module_put(policy->governor->owner); |
e788892b RW |
2047 | return ret; |
2048 | } | |
36be3418 | 2049 | } |
1da177e4 | 2050 | |
a92604b4 RW |
2051 | return 0; |
2052 | } | |
2053 | ||
2054 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2055 | { | |
2056 | if (cpufreq_suspended || !policy->governor) | |
2057 | return; | |
2058 | ||
2059 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2060 | ||
e788892b RW |
2061 | if (policy->governor->exit) |
2062 | policy->governor->exit(policy); | |
a92604b4 | 2063 | |
a92604b4 | 2064 | module_put(policy->governor->owner); |
1da177e4 LT |
2065 | } |
2066 | ||
0a300767 RW |
2067 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
2068 | { | |
2069 | int ret; | |
2070 | ||
a92604b4 RW |
2071 | if (cpufreq_suspended) |
2072 | return 0; | |
2073 | ||
2074 | if (!policy->governor) | |
2075 | return -EINVAL; | |
2076 | ||
2077 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2078 | ||
3bbf8fe3 RW |
2079 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) |
2080 | cpufreq_update_current_freq(policy); | |
2081 | ||
e788892b RW |
2082 | if (policy->governor->start) { |
2083 | ret = policy->governor->start(policy); | |
2084 | if (ret) | |
2085 | return ret; | |
2086 | } | |
2087 | ||
2088 | if (policy->governor->limits) | |
2089 | policy->governor->limits(policy); | |
d6ff44d6 | 2090 | |
d6ff44d6 | 2091 | return 0; |
0a300767 RW |
2092 | } |
2093 | ||
a92604b4 RW |
2094 | static void cpufreq_stop_governor(struct cpufreq_policy *policy) |
2095 | { | |
2096 | if (cpufreq_suspended || !policy->governor) | |
2097 | return; | |
2098 | ||
2099 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2100 | ||
e788892b RW |
2101 | if (policy->governor->stop) |
2102 | policy->governor->stop(policy); | |
a92604b4 RW |
2103 | } |
2104 | ||
2105 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2106 | { | |
2107 | if (cpufreq_suspended || !policy->governor) | |
2108 | return; | |
2109 | ||
2110 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2111 | ||
e788892b RW |
2112 | if (policy->governor->limits) |
2113 | policy->governor->limits(policy); | |
0a300767 RW |
2114 | } |
2115 | ||
1da177e4 LT |
2116 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2117 | { | |
3bcb09a3 | 2118 | int err; |
1da177e4 LT |
2119 | |
2120 | if (!governor) | |
2121 | return -EINVAL; | |
2122 | ||
a7b422cd KRW |
2123 | if (cpufreq_disabled()) |
2124 | return -ENODEV; | |
2125 | ||
3fc54d37 | 2126 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2127 | |
3bcb09a3 | 2128 | err = -EBUSY; |
42f91fa1 | 2129 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2130 | err = 0; |
2131 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2132 | } |
1da177e4 | 2133 | |
32ee8c3e | 2134 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2135 | return err; |
1da177e4 LT |
2136 | } |
2137 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2138 | ||
1da177e4 LT |
2139 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2140 | { | |
4573237b VK |
2141 | struct cpufreq_policy *policy; |
2142 | unsigned long flags; | |
90e41bac | 2143 | |
1da177e4 LT |
2144 | if (!governor) |
2145 | return; | |
2146 | ||
a7b422cd KRW |
2147 | if (cpufreq_disabled()) |
2148 | return; | |
2149 | ||
4573237b VK |
2150 | /* clear last_governor for all inactive policies */ |
2151 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2152 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2153 | if (!strcmp(policy->last_governor, governor->name)) { |
2154 | policy->governor = NULL; | |
4573237b | 2155 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2156 | } |
90e41bac | 2157 | } |
4573237b | 2158 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2159 | |
3fc54d37 | 2160 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2161 | list_del(&governor->governor_list); |
3fc54d37 | 2162 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2163 | return; |
2164 | } | |
2165 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2166 | ||
2167 | ||
1da177e4 LT |
2168 | /********************************************************************* |
2169 | * POLICY INTERFACE * | |
2170 | *********************************************************************/ | |
2171 | ||
2172 | /** | |
2173 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2174 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2175 | * is written | |
1da177e4 LT |
2176 | * |
2177 | * Reads the current cpufreq policy. | |
2178 | */ | |
2179 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2180 | { | |
2181 | struct cpufreq_policy *cpu_policy; | |
2182 | if (!policy) | |
2183 | return -EINVAL; | |
2184 | ||
2185 | cpu_policy = cpufreq_cpu_get(cpu); | |
2186 | if (!cpu_policy) | |
2187 | return -EINVAL; | |
2188 | ||
d5b73cd8 | 2189 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2190 | |
2191 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2192 | return 0; |
2193 | } | |
2194 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2195 | ||
153d7f3f | 2196 | /* |
037ce839 VK |
2197 | * policy : current policy. |
2198 | * new_policy: policy to be set. | |
153d7f3f | 2199 | */ |
037ce839 | 2200 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2201 | struct cpufreq_policy *new_policy) |
1da177e4 | 2202 | { |
d9a789c7 RW |
2203 | struct cpufreq_governor *old_gov; |
2204 | int ret; | |
1da177e4 | 2205 | |
e837f9b5 JP |
2206 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2207 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2208 | |
d5b73cd8 | 2209 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2210 | |
fba9573b PX |
2211 | /* |
2212 | * This check works well when we store new min/max freq attributes, | |
2213 | * because new_policy is a copy of policy with one field updated. | |
2214 | */ | |
2215 | if (new_policy->min > new_policy->max) | |
d9a789c7 | 2216 | return -EINVAL; |
9c9a43ed | 2217 | |
1da177e4 | 2218 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2219 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2220 | if (ret) |
d9a789c7 | 2221 | return ret; |
1da177e4 | 2222 | |
1da177e4 | 2223 | /* adjust if necessary - all reasons */ |
e041c683 | 2224 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2225 | CPUFREQ_ADJUST, new_policy); |
1da177e4 | 2226 | |
bb176f7d VK |
2227 | /* |
2228 | * verify the cpu speed can be set within this limit, which might be | |
2229 | * different to the first one | |
2230 | */ | |
3a3e9e06 | 2231 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2232 | if (ret) |
d9a789c7 | 2233 | return ret; |
1da177e4 LT |
2234 | |
2235 | /* notification of the new policy */ | |
e041c683 | 2236 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2237 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2238 | |
3a3e9e06 VK |
2239 | policy->min = new_policy->min; |
2240 | policy->max = new_policy->max; | |
1da177e4 | 2241 | |
e3c06236 SM |
2242 | policy->cached_target_freq = UINT_MAX; |
2243 | ||
2d06d8c4 | 2244 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2245 | policy->min, policy->max); |
1da177e4 | 2246 | |
1c3d85dd | 2247 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2248 | policy->policy = new_policy->policy; |
2d06d8c4 | 2249 | pr_debug("setting range\n"); |
d9a789c7 RW |
2250 | return cpufreq_driver->setpolicy(new_policy); |
2251 | } | |
1da177e4 | 2252 | |
0a300767 RW |
2253 | if (new_policy->governor == policy->governor) { |
2254 | pr_debug("cpufreq: governor limits update\n"); | |
a92604b4 | 2255 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2256 | return 0; |
0a300767 | 2257 | } |
7bd353a9 | 2258 | |
d9a789c7 RW |
2259 | pr_debug("governor switch\n"); |
2260 | ||
2261 | /* save old, working values */ | |
2262 | old_gov = policy->governor; | |
2263 | /* end old governor */ | |
2264 | if (old_gov) { | |
45482c70 | 2265 | cpufreq_stop_governor(policy); |
36be3418 | 2266 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2267 | } |
2268 | ||
d9a789c7 RW |
2269 | /* start new governor */ |
2270 | policy->governor = new_policy->governor; | |
a92604b4 | 2271 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2272 | if (!ret) { |
0a300767 RW |
2273 | ret = cpufreq_start_governor(policy); |
2274 | if (!ret) { | |
2275 | pr_debug("cpufreq: governor change\n"); | |
2276 | return 0; | |
2277 | } | |
b7898fda | 2278 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2279 | } |
2280 | ||
2281 | /* new governor failed, so re-start old one */ | |
2282 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2283 | if (old_gov) { | |
2284 | policy->governor = old_gov; | |
a92604b4 | 2285 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2286 | policy->governor = NULL; |
2287 | else | |
0a300767 | 2288 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2289 | } |
2290 | ||
4bc384ae | 2291 | return ret; |
1da177e4 LT |
2292 | } |
2293 | ||
1da177e4 LT |
2294 | /** |
2295 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2296 | * @cpu: CPU which shall be re-evaluated | |
2297 | * | |
25985edc | 2298 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2299 | * at different times. |
2300 | */ | |
30248fef | 2301 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2302 | { |
3a3e9e06 VK |
2303 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2304 | struct cpufreq_policy new_policy; | |
1da177e4 | 2305 | |
fefa8ff8 | 2306 | if (!policy) |
30248fef | 2307 | return; |
1da177e4 | 2308 | |
ad7722da | 2309 | down_write(&policy->rwsem); |
1da177e4 | 2310 | |
30248fef | 2311 | if (policy_is_inactive(policy)) |
182e36af | 2312 | goto unlock; |
182e36af | 2313 | |
2d06d8c4 | 2314 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2315 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2316 | new_policy.min = policy->user_policy.min; |
2317 | new_policy.max = policy->user_policy.max; | |
1da177e4 | 2318 | |
bb176f7d VK |
2319 | /* |
2320 | * BIOS might change freq behind our back | |
2321 | * -> ask driver for current freq and notify governors about a change | |
2322 | */ | |
2ed99e39 | 2323 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
30248fef | 2324 | if (cpufreq_suspended) |
742c87bf | 2325 | goto unlock; |
30248fef | 2326 | |
999f5729 | 2327 | new_policy.cur = cpufreq_update_current_freq(policy); |
30248fef | 2328 | if (WARN_ON(!new_policy.cur)) |
fefa8ff8 | 2329 | goto unlock; |
0961dd0d TR |
2330 | } |
2331 | ||
30248fef | 2332 | cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2333 | |
fefa8ff8 | 2334 | unlock: |
ad7722da | 2335 | up_write(&policy->rwsem); |
5a01f2e8 | 2336 | |
3a3e9e06 | 2337 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2338 | } |
2339 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2340 | ||
6f19efc0 LM |
2341 | /********************************************************************* |
2342 | * BOOST * | |
2343 | *********************************************************************/ | |
2344 | static int cpufreq_boost_set_sw(int state) | |
2345 | { | |
6f19efc0 LM |
2346 | struct cpufreq_policy *policy; |
2347 | int ret = -EINVAL; | |
2348 | ||
f963735a | 2349 | for_each_active_policy(policy) { |
f8bfc116 VK |
2350 | if (!policy->freq_table) |
2351 | continue; | |
49f18560 | 2352 | |
f8bfc116 VK |
2353 | ret = cpufreq_frequency_table_cpuinfo(policy, |
2354 | policy->freq_table); | |
2355 | if (ret) { | |
2356 | pr_err("%s: Policy frequency update failed\n", | |
2357 | __func__); | |
2358 | break; | |
6f19efc0 | 2359 | } |
f8bfc116 VK |
2360 | |
2361 | down_write(&policy->rwsem); | |
2362 | policy->user_policy.max = policy->max; | |
2363 | cpufreq_governor_limits(policy); | |
2364 | up_write(&policy->rwsem); | |
6f19efc0 LM |
2365 | } |
2366 | ||
2367 | return ret; | |
2368 | } | |
2369 | ||
2370 | int cpufreq_boost_trigger_state(int state) | |
2371 | { | |
2372 | unsigned long flags; | |
2373 | int ret = 0; | |
2374 | ||
2375 | if (cpufreq_driver->boost_enabled == state) | |
2376 | return 0; | |
2377 | ||
2378 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2379 | cpufreq_driver->boost_enabled = state; | |
2380 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2381 | ||
2382 | ret = cpufreq_driver->set_boost(state); | |
2383 | if (ret) { | |
2384 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2385 | cpufreq_driver->boost_enabled = !state; | |
2386 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2387 | ||
e837f9b5 JP |
2388 | pr_err("%s: Cannot %s BOOST\n", |
2389 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2390 | } |
2391 | ||
2392 | return ret; | |
2393 | } | |
2394 | ||
41669da0 | 2395 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2396 | { |
7a6c79f2 | 2397 | return likely(cpufreq_driver) && cpufreq_driver->set_boost; |
6f19efc0 | 2398 | } |
6f19efc0 | 2399 | |
44139ed4 VK |
2400 | static int create_boost_sysfs_file(void) |
2401 | { | |
2402 | int ret; | |
2403 | ||
c82bd444 | 2404 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2405 | if (ret) |
2406 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2407 | __func__); | |
2408 | ||
2409 | return ret; | |
2410 | } | |
2411 | ||
2412 | static void remove_boost_sysfs_file(void) | |
2413 | { | |
2414 | if (cpufreq_boost_supported()) | |
c82bd444 | 2415 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2416 | } |
2417 | ||
2418 | int cpufreq_enable_boost_support(void) | |
2419 | { | |
2420 | if (!cpufreq_driver) | |
2421 | return -EINVAL; | |
2422 | ||
2423 | if (cpufreq_boost_supported()) | |
2424 | return 0; | |
2425 | ||
7a6c79f2 | 2426 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2427 | |
2428 | /* This will get removed on driver unregister */ | |
2429 | return create_boost_sysfs_file(); | |
2430 | } | |
2431 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2432 | ||
6f19efc0 LM |
2433 | int cpufreq_boost_enabled(void) |
2434 | { | |
2435 | return cpufreq_driver->boost_enabled; | |
2436 | } | |
2437 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2438 | ||
1da177e4 LT |
2439 | /********************************************************************* |
2440 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2441 | *********************************************************************/ | |
27622b06 | 2442 | static enum cpuhp_state hp_online; |
1da177e4 | 2443 | |
c4a3fa26 CY |
2444 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2445 | { | |
2446 | cpufreq_online(cpu); | |
2447 | ||
2448 | return 0; | |
2449 | } | |
2450 | ||
2451 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2452 | { | |
2453 | cpufreq_offline(cpu); | |
2454 | ||
2455 | return 0; | |
2456 | } | |
2457 | ||
1da177e4 LT |
2458 | /** |
2459 | * cpufreq_register_driver - register a CPU Frequency driver | |
2460 | * @driver_data: A struct cpufreq_driver containing the values# | |
2461 | * submitted by the CPU Frequency driver. | |
2462 | * | |
bb176f7d | 2463 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2464 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2465 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2466 | * |
2467 | */ | |
221dee28 | 2468 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2469 | { |
2470 | unsigned long flags; | |
2471 | int ret; | |
2472 | ||
a7b422cd KRW |
2473 | if (cpufreq_disabled()) |
2474 | return -ENODEV; | |
2475 | ||
1da177e4 | 2476 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2477 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2478 | driver_data->target) || |
2479 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2480 | driver_data->target)) || |
2481 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2482 | return -EINVAL; |
2483 | ||
2d06d8c4 | 2484 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2485 | |
fdd320da | 2486 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2487 | cpus_read_lock(); |
fdd320da | 2488 | |
0d1857a1 | 2489 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2490 | if (cpufreq_driver) { |
0d1857a1 | 2491 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2492 | ret = -EEXIST; |
2493 | goto out; | |
1da177e4 | 2494 | } |
1c3d85dd | 2495 | cpufreq_driver = driver_data; |
0d1857a1 | 2496 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2497 | |
bc68b7df VK |
2498 | if (driver_data->setpolicy) |
2499 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2500 | ||
7a6c79f2 RW |
2501 | if (cpufreq_boost_supported()) { |
2502 | ret = create_boost_sysfs_file(); | |
2503 | if (ret) | |
2504 | goto err_null_driver; | |
2505 | } | |
6f19efc0 | 2506 | |
8a25a2fd | 2507 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2508 | if (ret) |
6f19efc0 | 2509 | goto err_boost_unreg; |
1da177e4 | 2510 | |
ce1bcfe9 VK |
2511 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2512 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2513 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2514 | ret = -ENODEV; |
ce1bcfe9 VK |
2515 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2516 | driver_data->name); | |
2517 | goto err_if_unreg; | |
1da177e4 LT |
2518 | } |
2519 | ||
a92551e4 SAS |
2520 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2521 | "cpufreq:online", | |
2522 | cpuhp_cpufreq_online, | |
2523 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2524 | if (ret < 0) |
2525 | goto err_if_unreg; | |
2526 | hp_online = ret; | |
5372e054 | 2527 | ret = 0; |
27622b06 | 2528 | |
2d06d8c4 | 2529 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2530 | goto out; |
fdd320da | 2531 | |
8a25a2fd KS |
2532 | err_if_unreg: |
2533 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2534 | err_boost_unreg: |
44139ed4 | 2535 | remove_boost_sysfs_file(); |
8f5bc2ab | 2536 | err_null_driver: |
0d1857a1 | 2537 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2538 | cpufreq_driver = NULL; |
0d1857a1 | 2539 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2540 | out: |
a92551e4 | 2541 | cpus_read_unlock(); |
3834abb4 | 2542 | return ret; |
1da177e4 LT |
2543 | } |
2544 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2545 | ||
1da177e4 LT |
2546 | /** |
2547 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2548 | * | |
bb176f7d | 2549 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2550 | * the right to do so, i.e. if you have succeeded in initialising before! |
2551 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2552 | * currently not initialised. | |
2553 | */ | |
221dee28 | 2554 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2555 | { |
2556 | unsigned long flags; | |
2557 | ||
1c3d85dd | 2558 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2559 | return -EINVAL; |
1da177e4 | 2560 | |
2d06d8c4 | 2561 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2562 | |
454d3a25 | 2563 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2564 | cpus_read_lock(); |
8a25a2fd | 2565 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2566 | remove_boost_sysfs_file(); |
a92551e4 | 2567 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2568 | |
0d1857a1 | 2569 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2570 | |
1c3d85dd | 2571 | cpufreq_driver = NULL; |
6eed9404 | 2572 | |
0d1857a1 | 2573 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2574 | cpus_read_unlock(); |
1da177e4 LT |
2575 | |
2576 | return 0; | |
2577 | } | |
2578 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2579 | |
90de2a4a DA |
2580 | /* |
2581 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2582 | * or mutexes when secondary CPUs are halted. | |
2583 | */ | |
2584 | static struct syscore_ops cpufreq_syscore_ops = { | |
2585 | .shutdown = cpufreq_suspend, | |
2586 | }; | |
2587 | ||
c82bd444 VK |
2588 | struct kobject *cpufreq_global_kobject; |
2589 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2590 | ||
5a01f2e8 VP |
2591 | static int __init cpufreq_core_init(void) |
2592 | { | |
a7b422cd KRW |
2593 | if (cpufreq_disabled()) |
2594 | return -ENODEV; | |
2595 | ||
8eec1020 | 2596 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2597 | BUG_ON(!cpufreq_global_kobject); |
2598 | ||
90de2a4a DA |
2599 | register_syscore_ops(&cpufreq_syscore_ops); |
2600 | ||
5a01f2e8 VP |
2601 | return 0; |
2602 | } | |
d82f2692 | 2603 | module_param(off, int, 0444); |
5a01f2e8 | 2604 | core_initcall(cpufreq_core_init); |