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Commit | Line | Data |
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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 */ |
a1317e09 | 77 | static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event); |
d92d50a4 | 78 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
0a300767 | 79 | static int cpufreq_start_governor(struct cpufreq_policy *policy); |
b7898fda | 80 | static int cpufreq_exit_governor(struct cpufreq_policy *policy); |
1da177e4 LT |
81 | |
82 | /** | |
32ee8c3e DJ |
83 | * Two notifier lists: the "policy" list is involved in the |
84 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
85 | * "transition" list for kernel code that needs to handle |
86 | * changes to devices when the CPU clock speed changes. | |
87 | * The mutex locks both lists. | |
88 | */ | |
e041c683 | 89 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 90 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 91 | |
74212ca4 | 92 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
93 | static int __init init_cpufreq_transition_notifier_list(void) |
94 | { | |
95 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 96 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
97 | return 0; |
98 | } | |
b3438f82 | 99 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 100 | |
a7b422cd | 101 | static int off __read_mostly; |
da584455 | 102 | static int cpufreq_disabled(void) |
a7b422cd KRW |
103 | { |
104 | return off; | |
105 | } | |
106 | void disable_cpufreq(void) | |
107 | { | |
108 | off = 1; | |
109 | } | |
29464f28 | 110 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 111 | |
4d5dcc42 VK |
112 | bool have_governor_per_policy(void) |
113 | { | |
0b981e70 | 114 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 115 | } |
3f869d6d | 116 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 117 | |
944e9a03 VK |
118 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
119 | { | |
120 | if (have_governor_per_policy()) | |
121 | return &policy->kobj; | |
122 | else | |
123 | return cpufreq_global_kobject; | |
124 | } | |
125 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
126 | ||
5a31d594 VK |
127 | struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu) |
128 | { | |
129 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
130 | ||
131 | return policy && !policy_is_inactive(policy) ? | |
132 | policy->freq_table : NULL; | |
133 | } | |
134 | EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table); | |
135 | ||
72a4ce34 VK |
136 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
137 | { | |
138 | u64 idle_time; | |
139 | u64 cur_wall_time; | |
140 | u64 busy_time; | |
141 | ||
142 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
143 | ||
144 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
145 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
146 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
147 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
148 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
149 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
150 | ||
151 | idle_time = cur_wall_time - busy_time; | |
152 | if (wall) | |
153 | *wall = cputime_to_usecs(cur_wall_time); | |
154 | ||
155 | return cputime_to_usecs(idle_time); | |
156 | } | |
157 | ||
158 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
159 | { | |
160 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
161 | ||
162 | if (idle_time == -1ULL) | |
163 | return get_cpu_idle_time_jiffy(cpu, wall); | |
164 | else if (!io_busy) | |
165 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
166 | ||
167 | return idle_time; | |
168 | } | |
169 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
170 | ||
70e9e778 VK |
171 | /* |
172 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
173 | * drivers of SMP systems. It will do following: | |
174 | * - validate & show freq table passed | |
175 | * - set policies transition latency | |
176 | * - policy->cpus with all possible CPUs | |
177 | */ | |
178 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
179 | struct cpufreq_frequency_table *table, | |
180 | unsigned int transition_latency) | |
181 | { | |
182 | int ret; | |
183 | ||
184 | ret = cpufreq_table_validate_and_show(policy, table); | |
185 | if (ret) { | |
186 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
187 | return ret; | |
188 | } | |
189 | ||
190 | policy->cpuinfo.transition_latency = transition_latency; | |
191 | ||
192 | /* | |
58405af6 | 193 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
194 | * share the clock and voltage and clock. |
195 | */ | |
196 | cpumask_setall(policy->cpus); | |
197 | ||
198 | return 0; | |
199 | } | |
200 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
201 | ||
1f0bd44e | 202 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
203 | { |
204 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
205 | ||
988bed09 VK |
206 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
207 | } | |
1f0bd44e | 208 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
209 | |
210 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
211 | { | |
212 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
213 | ||
652ed95d | 214 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
215 | pr_err("%s: No %s associated to cpu: %d\n", |
216 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
217 | return 0; |
218 | } | |
219 | ||
220 | return clk_get_rate(policy->clk) / 1000; | |
221 | } | |
222 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
223 | ||
50e9c852 VK |
224 | /** |
225 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
226 | * | |
227 | * @cpu: cpu to find policy for. | |
228 | * | |
229 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
230 | * It also increments the kobject reference count to mark it busy and so would | |
231 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
232 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
233 | * freed as that depends on the kobj count. | |
234 | * | |
50e9c852 VK |
235 | * Return: A valid policy on success, otherwise NULL on failure. |
236 | */ | |
6eed9404 | 237 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 238 | { |
6eed9404 | 239 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
240 | unsigned long flags; |
241 | ||
1b947c90 | 242 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
243 | return NULL; |
244 | ||
1da177e4 | 245 | /* get the cpufreq driver */ |
1c3d85dd | 246 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 247 | |
6eed9404 VK |
248 | if (cpufreq_driver) { |
249 | /* get the CPU */ | |
988bed09 | 250 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
251 | if (policy) |
252 | kobject_get(&policy->kobj); | |
253 | } | |
1da177e4 | 254 | |
6eed9404 | 255 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 256 | |
3a3e9e06 | 257 | return policy; |
a9144436 | 258 | } |
1da177e4 LT |
259 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
260 | ||
50e9c852 VK |
261 | /** |
262 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
263 | * | |
264 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
265 | * | |
266 | * This decrements the kobject reference count incremented earlier by calling | |
267 | * cpufreq_cpu_get(). | |
50e9c852 | 268 | */ |
3a3e9e06 | 269 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 270 | { |
6eed9404 | 271 | kobject_put(&policy->kobj); |
1da177e4 LT |
272 | } |
273 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
274 | ||
1da177e4 LT |
275 | /********************************************************************* |
276 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
277 | *********************************************************************/ | |
278 | ||
279 | /** | |
280 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
281 | * | |
282 | * This function alters the system "loops_per_jiffy" for the clock | |
283 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 284 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
285 | * per-CPU loops_per_jiffy value wherever possible. |
286 | */ | |
858119e1 | 287 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 288 | { |
39c132ee VK |
289 | #ifndef CONFIG_SMP |
290 | static unsigned long l_p_j_ref; | |
291 | static unsigned int l_p_j_ref_freq; | |
292 | ||
1da177e4 LT |
293 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
294 | return; | |
295 | ||
296 | if (!l_p_j_ref_freq) { | |
297 | l_p_j_ref = loops_per_jiffy; | |
298 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
299 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
300 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 301 | } |
0b443ead | 302 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
303 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
304 | ci->new); | |
e837f9b5 JP |
305 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
306 | loops_per_jiffy, ci->new); | |
1da177e4 | 307 | } |
1da177e4 | 308 | #endif |
39c132ee | 309 | } |
1da177e4 | 310 | |
0956df9c | 311 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 312 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
313 | { |
314 | BUG_ON(irqs_disabled()); | |
315 | ||
d5aaffa9 DB |
316 | if (cpufreq_disabled()) |
317 | return; | |
318 | ||
1c3d85dd | 319 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 320 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 321 | state, freqs->new); |
1da177e4 | 322 | |
1da177e4 | 323 | switch (state) { |
e4472cb3 | 324 | |
1da177e4 | 325 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 326 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
327 | * which is not equal to what the cpufreq core thinks is |
328 | * "old frequency". | |
1da177e4 | 329 | */ |
1c3d85dd | 330 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
331 | if ((policy) && (policy->cpu == freqs->cpu) && |
332 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
333 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
334 | freqs->old, policy->cur); | |
e4472cb3 | 335 | freqs->old = policy->cur; |
1da177e4 LT |
336 | } |
337 | } | |
b4dfdbb3 | 338 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 339 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
340 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
341 | break; | |
e4472cb3 | 342 | |
1da177e4 LT |
343 | case CPUFREQ_POSTCHANGE: |
344 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
345 | pr_debug("FREQ: %lu - CPU: %lu\n", |
346 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 347 | trace_cpu_frequency(freqs->new, freqs->cpu); |
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 | ||
485 | static void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
486 | { | |
487 | mutex_lock(&cpufreq_fast_switch_lock); | |
488 | if (policy->fast_switch_enabled) { | |
489 | policy->fast_switch_enabled = false; | |
490 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
491 | cpufreq_fast_switch_count--; | |
492 | } | |
493 | mutex_unlock(&cpufreq_fast_switch_lock); | |
494 | } | |
1da177e4 | 495 | |
1da177e4 LT |
496 | /********************************************************************* |
497 | * SYSFS INTERFACE * | |
498 | *********************************************************************/ | |
8a5c74a1 | 499 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
500 | struct attribute *attr, char *buf) |
501 | { | |
502 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
503 | } | |
504 | ||
505 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
506 | const char *buf, size_t count) | |
507 | { | |
508 | int ret, enable; | |
509 | ||
510 | ret = sscanf(buf, "%d", &enable); | |
511 | if (ret != 1 || enable < 0 || enable > 1) | |
512 | return -EINVAL; | |
513 | ||
514 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
515 | pr_err("%s: Cannot %s BOOST!\n", |
516 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
517 | return -EINVAL; |
518 | } | |
519 | ||
e837f9b5 JP |
520 | pr_debug("%s: cpufreq BOOST %s\n", |
521 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
522 | |
523 | return count; | |
524 | } | |
525 | define_one_global_rw(boost); | |
1da177e4 | 526 | |
42f91fa1 | 527 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
528 | { |
529 | struct cpufreq_governor *t; | |
530 | ||
f7b27061 | 531 | for_each_governor(t) |
7c4f4539 | 532 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
533 | return t; |
534 | ||
535 | return NULL; | |
536 | } | |
537 | ||
1da177e4 LT |
538 | /** |
539 | * cpufreq_parse_governor - parse a governor string | |
540 | */ | |
905d77cd | 541 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
542 | struct cpufreq_governor **governor) |
543 | { | |
3bcb09a3 | 544 | int err = -EINVAL; |
1c3d85dd | 545 | |
1c3d85dd | 546 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 547 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 548 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 549 | err = 0; |
7c4f4539 | 550 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 551 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 552 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 553 | err = 0; |
1da177e4 | 554 | } |
2e1cc3a5 | 555 | } else { |
1da177e4 | 556 | struct cpufreq_governor *t; |
3bcb09a3 | 557 | |
3fc54d37 | 558 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 559 | |
42f91fa1 | 560 | t = find_governor(str_governor); |
3bcb09a3 | 561 | |
ea714970 | 562 | if (t == NULL) { |
1a8e1463 | 563 | int ret; |
ea714970 | 564 | |
1a8e1463 KC |
565 | mutex_unlock(&cpufreq_governor_mutex); |
566 | ret = request_module("cpufreq_%s", str_governor); | |
567 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 568 | |
1a8e1463 | 569 | if (ret == 0) |
42f91fa1 | 570 | t = find_governor(str_governor); |
ea714970 JF |
571 | } |
572 | ||
3bcb09a3 JF |
573 | if (t != NULL) { |
574 | *governor = t; | |
575 | err = 0; | |
1da177e4 | 576 | } |
3bcb09a3 | 577 | |
3fc54d37 | 578 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 579 | } |
3bcb09a3 | 580 | return err; |
1da177e4 | 581 | } |
1da177e4 | 582 | |
1da177e4 | 583 | /** |
e08f5f5b GS |
584 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
585 | * print out cpufreq information | |
1da177e4 LT |
586 | * |
587 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
588 | * "unsigned int". | |
589 | */ | |
590 | ||
32ee8c3e DJ |
591 | #define show_one(file_name, object) \ |
592 | static ssize_t show_##file_name \ | |
905d77cd | 593 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 594 | { \ |
29464f28 | 595 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
596 | } |
597 | ||
598 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
599 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 600 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
601 | show_one(scaling_min_freq, min); |
602 | show_one(scaling_max_freq, max); | |
c034b02e | 603 | |
09347b29 | 604 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
605 | { |
606 | ssize_t ret; | |
607 | ||
608 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
609 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
610 | else | |
611 | ret = sprintf(buf, "%u\n", policy->cur); | |
612 | return ret; | |
613 | } | |
1da177e4 | 614 | |
037ce839 | 615 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 616 | struct cpufreq_policy *new_policy); |
7970e08b | 617 | |
1da177e4 LT |
618 | /** |
619 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
620 | */ | |
621 | #define store_one(file_name, object) \ | |
622 | static ssize_t store_##file_name \ | |
905d77cd | 623 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 624 | { \ |
619c144c | 625 | int ret, temp; \ |
1da177e4 LT |
626 | struct cpufreq_policy new_policy; \ |
627 | \ | |
8fa5b631 | 628 | memcpy(&new_policy, policy, sizeof(*policy)); \ |
1da177e4 | 629 | \ |
29464f28 | 630 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
631 | if (ret != 1) \ |
632 | return -EINVAL; \ | |
633 | \ | |
619c144c | 634 | temp = new_policy.object; \ |
037ce839 | 635 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
636 | if (!ret) \ |
637 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
638 | \ |
639 | return ret ? ret : count; \ | |
640 | } | |
641 | ||
29464f28 DJ |
642 | store_one(scaling_min_freq, min); |
643 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
644 | |
645 | /** | |
646 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
647 | */ | |
905d77cd DJ |
648 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
649 | char *buf) | |
1da177e4 | 650 | { |
d92d50a4 | 651 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
652 | if (!cur_freq) |
653 | return sprintf(buf, "<unknown>"); | |
654 | return sprintf(buf, "%u\n", cur_freq); | |
655 | } | |
656 | ||
1da177e4 LT |
657 | /** |
658 | * show_scaling_governor - show the current policy for the specified CPU | |
659 | */ | |
905d77cd | 660 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 661 | { |
29464f28 | 662 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
663 | return sprintf(buf, "powersave\n"); |
664 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
665 | return sprintf(buf, "performance\n"); | |
666 | else if (policy->governor) | |
4b972f0b | 667 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 668 | policy->governor->name); |
1da177e4 LT |
669 | return -EINVAL; |
670 | } | |
671 | ||
1da177e4 LT |
672 | /** |
673 | * store_scaling_governor - store policy for the specified CPU | |
674 | */ | |
905d77cd DJ |
675 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
676 | const char *buf, size_t count) | |
1da177e4 | 677 | { |
5136fa56 | 678 | int ret; |
1da177e4 LT |
679 | char str_governor[16]; |
680 | struct cpufreq_policy new_policy; | |
681 | ||
8fa5b631 | 682 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 683 | |
29464f28 | 684 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
685 | if (ret != 1) |
686 | return -EINVAL; | |
687 | ||
e08f5f5b GS |
688 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
689 | &new_policy.governor)) | |
1da177e4 LT |
690 | return -EINVAL; |
691 | ||
037ce839 | 692 | ret = cpufreq_set_policy(policy, &new_policy); |
88dc4384 | 693 | return ret ? ret : count; |
1da177e4 LT |
694 | } |
695 | ||
696 | /** | |
697 | * show_scaling_driver - show the cpufreq driver currently loaded | |
698 | */ | |
905d77cd | 699 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 700 | { |
1c3d85dd | 701 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
702 | } |
703 | ||
704 | /** | |
705 | * show_scaling_available_governors - show the available CPUfreq governors | |
706 | */ | |
905d77cd DJ |
707 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
708 | char *buf) | |
1da177e4 LT |
709 | { |
710 | ssize_t i = 0; | |
711 | struct cpufreq_governor *t; | |
712 | ||
9c0ebcf7 | 713 | if (!has_target()) { |
1da177e4 LT |
714 | i += sprintf(buf, "performance powersave"); |
715 | goto out; | |
716 | } | |
717 | ||
f7b27061 | 718 | for_each_governor(t) { |
29464f28 DJ |
719 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
720 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 721 | goto out; |
4b972f0b | 722 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 723 | } |
7d5e350f | 724 | out: |
1da177e4 LT |
725 | i += sprintf(&buf[i], "\n"); |
726 | return i; | |
727 | } | |
e8628dd0 | 728 | |
f4fd3797 | 729 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
730 | { |
731 | ssize_t i = 0; | |
732 | unsigned int cpu; | |
733 | ||
835481d9 | 734 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
735 | if (i) |
736 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
737 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
738 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 739 | break; |
1da177e4 LT |
740 | } |
741 | i += sprintf(&buf[i], "\n"); | |
742 | return i; | |
743 | } | |
f4fd3797 | 744 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 745 | |
e8628dd0 DW |
746 | /** |
747 | * show_related_cpus - show the CPUs affected by each transition even if | |
748 | * hw coordination is in use | |
749 | */ | |
750 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
751 | { | |
f4fd3797 | 752 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
753 | } |
754 | ||
755 | /** | |
756 | * show_affected_cpus - show the CPUs affected by each transition | |
757 | */ | |
758 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
759 | { | |
f4fd3797 | 760 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
761 | } |
762 | ||
9e76988e | 763 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 764 | const char *buf, size_t count) |
9e76988e VP |
765 | { |
766 | unsigned int freq = 0; | |
767 | unsigned int ret; | |
768 | ||
879000f9 | 769 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
770 | return -EINVAL; |
771 | ||
772 | ret = sscanf(buf, "%u", &freq); | |
773 | if (ret != 1) | |
774 | return -EINVAL; | |
775 | ||
776 | policy->governor->store_setspeed(policy, freq); | |
777 | ||
778 | return count; | |
779 | } | |
780 | ||
781 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
782 | { | |
879000f9 | 783 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
784 | return sprintf(buf, "<unsupported>\n"); |
785 | ||
786 | return policy->governor->show_setspeed(policy, buf); | |
787 | } | |
1da177e4 | 788 | |
e2f74f35 | 789 | /** |
8bf1ac72 | 790 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
791 | */ |
792 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
793 | { | |
794 | unsigned int limit; | |
795 | int ret; | |
1c3d85dd RW |
796 | if (cpufreq_driver->bios_limit) { |
797 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
798 | if (!ret) |
799 | return sprintf(buf, "%u\n", limit); | |
800 | } | |
801 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
802 | } | |
803 | ||
6dad2a29 BP |
804 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
805 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
806 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
807 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
808 | cpufreq_freq_attr_ro(scaling_available_governors); | |
809 | cpufreq_freq_attr_ro(scaling_driver); | |
810 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
811 | cpufreq_freq_attr_ro(bios_limit); | |
812 | cpufreq_freq_attr_ro(related_cpus); | |
813 | cpufreq_freq_attr_ro(affected_cpus); | |
814 | cpufreq_freq_attr_rw(scaling_min_freq); | |
815 | cpufreq_freq_attr_rw(scaling_max_freq); | |
816 | cpufreq_freq_attr_rw(scaling_governor); | |
817 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 818 | |
905d77cd | 819 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
820 | &cpuinfo_min_freq.attr, |
821 | &cpuinfo_max_freq.attr, | |
ed129784 | 822 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
823 | &scaling_min_freq.attr, |
824 | &scaling_max_freq.attr, | |
825 | &affected_cpus.attr, | |
e8628dd0 | 826 | &related_cpus.attr, |
1da177e4 LT |
827 | &scaling_governor.attr, |
828 | &scaling_driver.attr, | |
829 | &scaling_available_governors.attr, | |
9e76988e | 830 | &scaling_setspeed.attr, |
1da177e4 LT |
831 | NULL |
832 | }; | |
833 | ||
29464f28 DJ |
834 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
835 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 836 | |
29464f28 | 837 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 838 | { |
905d77cd DJ |
839 | struct cpufreq_policy *policy = to_policy(kobj); |
840 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 841 | ssize_t ret; |
6eed9404 | 842 | |
ad7722da | 843 | down_read(&policy->rwsem); |
6541aef0 | 844 | ret = fattr->show(policy, buf); |
ad7722da | 845 | up_read(&policy->rwsem); |
1b750e3b | 846 | |
1da177e4 LT |
847 | return ret; |
848 | } | |
849 | ||
905d77cd DJ |
850 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
851 | const char *buf, size_t count) | |
1da177e4 | 852 | { |
905d77cd DJ |
853 | struct cpufreq_policy *policy = to_policy(kobj); |
854 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 855 | ssize_t ret = -EINVAL; |
6eed9404 | 856 | |
4f750c93 SB |
857 | get_online_cpus(); |
858 | ||
6541aef0 RW |
859 | if (cpu_online(policy->cpu)) { |
860 | down_write(&policy->rwsem); | |
e08f5f5b | 861 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
862 | up_write(&policy->rwsem); |
863 | } | |
e08f5f5b | 864 | |
4f750c93 SB |
865 | put_online_cpus(); |
866 | ||
1da177e4 LT |
867 | return ret; |
868 | } | |
869 | ||
905d77cd | 870 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 871 | { |
905d77cd | 872 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 873 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
874 | complete(&policy->kobj_unregister); |
875 | } | |
876 | ||
52cf25d0 | 877 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
878 | .show = show, |
879 | .store = store, | |
880 | }; | |
881 | ||
882 | static struct kobj_type ktype_cpufreq = { | |
883 | .sysfs_ops = &sysfs_ops, | |
884 | .default_attrs = default_attrs, | |
885 | .release = cpufreq_sysfs_release, | |
886 | }; | |
887 | ||
87549141 VK |
888 | static int add_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) |
889 | { | |
890 | struct device *cpu_dev; | |
891 | ||
892 | pr_debug("%s: Adding symlink for CPU: %u\n", __func__, cpu); | |
893 | ||
894 | if (!policy) | |
895 | return 0; | |
896 | ||
897 | cpu_dev = get_cpu_device(cpu); | |
898 | if (WARN_ON(!cpu_dev)) | |
899 | return 0; | |
900 | ||
901 | return sysfs_create_link(&cpu_dev->kobj, &policy->kobj, "cpufreq"); | |
902 | } | |
903 | ||
904 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) | |
905 | { | |
906 | struct device *cpu_dev; | |
907 | ||
908 | pr_debug("%s: Removing symlink for CPU: %u\n", __func__, cpu); | |
909 | ||
910 | cpu_dev = get_cpu_device(cpu); | |
911 | if (WARN_ON(!cpu_dev)) | |
912 | return; | |
913 | ||
914 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); | |
915 | } | |
916 | ||
917 | /* Add/remove symlinks for all related CPUs */ | |
308b60e7 | 918 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
919 | { |
920 | unsigned int j; | |
921 | int ret = 0; | |
922 | ||
87549141 | 923 | /* Some related CPUs might not be present (physically hotplugged) */ |
559ed407 | 924 | for_each_cpu(j, policy->real_cpus) { |
87549141 | 925 | ret = add_cpu_dev_symlink(policy, j); |
71c3461e RW |
926 | if (ret) |
927 | break; | |
19d6f7ec | 928 | } |
87549141 | 929 | |
19d6f7ec DJ |
930 | return ret; |
931 | } | |
932 | ||
87549141 VK |
933 | static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy) |
934 | { | |
935 | unsigned int j; | |
936 | ||
937 | /* Some related CPUs might not be present (physically hotplugged) */ | |
96bdda61 | 938 | for_each_cpu(j, policy->real_cpus) |
87549141 | 939 | remove_cpu_dev_symlink(policy, j); |
87549141 VK |
940 | } |
941 | ||
d9612a49 | 942 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
943 | { |
944 | struct freq_attr **drv_attr; | |
909a694e | 945 | int ret = 0; |
909a694e | 946 | |
909a694e | 947 | /* set up files for this cpu device */ |
1c3d85dd | 948 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 949 | while (drv_attr && *drv_attr) { |
909a694e DJ |
950 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
951 | if (ret) | |
6d4e81ed | 952 | return ret; |
909a694e DJ |
953 | drv_attr++; |
954 | } | |
1c3d85dd | 955 | if (cpufreq_driver->get) { |
909a694e DJ |
956 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
957 | if (ret) | |
6d4e81ed | 958 | return ret; |
909a694e | 959 | } |
c034b02e DB |
960 | |
961 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
962 | if (ret) | |
6d4e81ed | 963 | return ret; |
c034b02e | 964 | |
1c3d85dd | 965 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
966 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
967 | if (ret) | |
6d4e81ed | 968 | return ret; |
e2f74f35 | 969 | } |
909a694e | 970 | |
6d4e81ed | 971 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
972 | } |
973 | ||
de1df26b RW |
974 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
975 | { | |
976 | return NULL; | |
977 | } | |
978 | ||
7f0fa40f | 979 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 980 | { |
6e2c89d1 | 981 | struct cpufreq_governor *gov = NULL; |
e18f1682 | 982 | struct cpufreq_policy new_policy; |
e18f1682 | 983 | |
d5b73cd8 | 984 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 985 | |
6e2c89d1 | 986 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 987 | gov = find_governor(policy->last_governor); |
de1df26b | 988 | if (gov) { |
6e2c89d1 | 989 | pr_debug("Restoring governor %s for cpu %d\n", |
990 | policy->governor->name, policy->cpu); | |
de1df26b RW |
991 | } else { |
992 | gov = cpufreq_default_governor(); | |
993 | if (!gov) | |
994 | return -ENODATA; | |
995 | } | |
6e2c89d1 | 996 | |
997 | new_policy.governor = gov; | |
998 | ||
69030dd1 SP |
999 | /* Use the default policy if there is no last_policy. */ |
1000 | if (cpufreq_driver->setpolicy) { | |
1001 | if (policy->last_policy) | |
1002 | new_policy.policy = policy->last_policy; | |
1003 | else | |
1004 | cpufreq_parse_governor(gov->name, &new_policy.policy, | |
1005 | NULL); | |
1006 | } | |
ecf7e461 | 1007 | /* set default policy */ |
7f0fa40f | 1008 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
1009 | } |
1010 | ||
d9612a49 | 1011 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1012 | { |
9c0ebcf7 | 1013 | int ret = 0; |
fcf80582 | 1014 | |
bb29ae15 VK |
1015 | /* Has this CPU been taken care of already? */ |
1016 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1017 | return 0; | |
1018 | ||
49f18560 | 1019 | down_write(&policy->rwsem); |
9c0ebcf7 | 1020 | if (has_target()) { |
a1317e09 | 1021 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
3de9bdeb VK |
1022 | if (ret) { |
1023 | pr_err("%s: Failed to stop governor\n", __func__); | |
49f18560 | 1024 | goto unlock; |
3de9bdeb VK |
1025 | } |
1026 | } | |
fcf80582 | 1027 | |
fcf80582 | 1028 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1029 | |
9c0ebcf7 | 1030 | if (has_target()) { |
0a300767 | 1031 | ret = cpufreq_start_governor(policy); |
49f18560 | 1032 | if (ret) |
3de9bdeb | 1033 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1034 | } |
fcf80582 | 1035 | |
49f18560 VK |
1036 | unlock: |
1037 | up_write(&policy->rwsem); | |
1038 | return ret; | |
fcf80582 | 1039 | } |
1da177e4 | 1040 | |
11eb69b9 VK |
1041 | static void handle_update(struct work_struct *work) |
1042 | { | |
1043 | struct cpufreq_policy *policy = | |
1044 | container_of(work, struct cpufreq_policy, update); | |
1045 | unsigned int cpu = policy->cpu; | |
1046 | pr_debug("handle_update for cpu %u called\n", cpu); | |
1047 | cpufreq_update_policy(cpu); | |
fcf80582 | 1048 | } |
1da177e4 | 1049 | |
a34e63b1 | 1050 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 | 1051 | { |
a34e63b1 | 1052 | struct device *dev = get_cpu_device(cpu); |
e9698cc5 | 1053 | struct cpufreq_policy *policy; |
edd4a893 | 1054 | int ret; |
e9698cc5 | 1055 | |
a34e63b1 RW |
1056 | if (WARN_ON(!dev)) |
1057 | return NULL; | |
1058 | ||
e9698cc5 SB |
1059 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1060 | if (!policy) | |
1061 | return NULL; | |
1062 | ||
1063 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1064 | goto err_free_policy; | |
1065 | ||
1066 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1067 | goto err_free_cpumask; | |
1068 | ||
559ed407 RW |
1069 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1070 | goto err_free_rcpumask; | |
1071 | ||
edd4a893 VK |
1072 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1073 | cpufreq_global_kobject, "policy%u", cpu); | |
1074 | if (ret) { | |
1075 | pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); | |
1076 | goto err_free_real_cpus; | |
1077 | } | |
1078 | ||
c88a1f8b | 1079 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1080 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1081 | spin_lock_init(&policy->transition_lock); |
1082 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1083 | init_completion(&policy->kobj_unregister); |
1084 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1085 | |
a34e63b1 | 1086 | policy->cpu = cpu; |
e9698cc5 SB |
1087 | return policy; |
1088 | ||
edd4a893 VK |
1089 | err_free_real_cpus: |
1090 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1091 | err_free_rcpumask: |
1092 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1093 | err_free_cpumask: |
1094 | free_cpumask_var(policy->cpus); | |
1095 | err_free_policy: | |
1096 | kfree(policy); | |
1097 | ||
1098 | return NULL; | |
1099 | } | |
1100 | ||
2fc3384d | 1101 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify) |
42f921a6 VK |
1102 | { |
1103 | struct kobject *kobj; | |
1104 | struct completion *cmp; | |
1105 | ||
2fc3384d VK |
1106 | if (notify) |
1107 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1108 | CPUFREQ_REMOVE_POLICY, policy); | |
fcd7af91 | 1109 | |
87549141 VK |
1110 | down_write(&policy->rwsem); |
1111 | cpufreq_remove_dev_symlink(policy); | |
42f921a6 VK |
1112 | kobj = &policy->kobj; |
1113 | cmp = &policy->kobj_unregister; | |
87549141 | 1114 | up_write(&policy->rwsem); |
42f921a6 VK |
1115 | kobject_put(kobj); |
1116 | ||
1117 | /* | |
1118 | * We need to make sure that the underlying kobj is | |
1119 | * actually not referenced anymore by anybody before we | |
1120 | * proceed with unloading. | |
1121 | */ | |
1122 | pr_debug("waiting for dropping of refcount\n"); | |
1123 | wait_for_completion(cmp); | |
1124 | pr_debug("wait complete\n"); | |
1125 | } | |
1126 | ||
3654c5cc | 1127 | static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify) |
e9698cc5 | 1128 | { |
988bed09 VK |
1129 | unsigned long flags; |
1130 | int cpu; | |
1131 | ||
1132 | /* Remove policy from list */ | |
1133 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1134 | list_del(&policy->policy_list); | |
1135 | ||
1136 | for_each_cpu(cpu, policy->related_cpus) | |
1137 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1138 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1139 | ||
3654c5cc | 1140 | cpufreq_policy_put_kobj(policy, notify); |
559ed407 | 1141 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1142 | free_cpumask_var(policy->related_cpus); |
1143 | free_cpumask_var(policy->cpus); | |
1144 | kfree(policy); | |
1145 | } | |
1146 | ||
0b275352 | 1147 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1148 | { |
7f0c020a | 1149 | struct cpufreq_policy *policy; |
194d99c7 | 1150 | bool new_policy; |
1da177e4 | 1151 | unsigned long flags; |
0b275352 RW |
1152 | unsigned int j; |
1153 | int ret; | |
87549141 | 1154 | |
0b275352 | 1155 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1156 | |
bb29ae15 | 1157 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1158 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1159 | if (policy) { |
9104bb26 | 1160 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1161 | if (!policy_is_inactive(policy)) |
d9612a49 | 1162 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1163 | |
11ce707e | 1164 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1165 | new_policy = false; |
11ce707e RW |
1166 | down_write(&policy->rwsem); |
1167 | policy->cpu = cpu; | |
1168 | policy->governor = NULL; | |
1169 | up_write(&policy->rwsem); | |
1170 | } else { | |
194d99c7 | 1171 | new_policy = true; |
a34e63b1 | 1172 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1173 | if (!policy) |
d4d854d6 | 1174 | return -ENOMEM; |
72368d12 | 1175 | } |
0d66b91e | 1176 | |
835481d9 | 1177 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1178 | |
1da177e4 LT |
1179 | /* call driver. From then on the cpufreq must be able |
1180 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1181 | */ | |
1c3d85dd | 1182 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1183 | if (ret) { |
2d06d8c4 | 1184 | pr_debug("initialization failed\n"); |
8101f997 | 1185 | goto out_free_policy; |
1da177e4 | 1186 | } |
643ae6e8 | 1187 | |
6d4e81ed TV |
1188 | down_write(&policy->rwsem); |
1189 | ||
194d99c7 | 1190 | if (new_policy) { |
4d1f3a5b | 1191 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1192 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1193 | /* Remember CPUs present at the policy creation time. */ |
559ed407 | 1194 | cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask); |
4d1f3a5b | 1195 | } |
559ed407 | 1196 | |
5a7e56a5 VK |
1197 | /* |
1198 | * affected cpus must always be the one, which are online. We aren't | |
1199 | * managing offline cpus here. | |
1200 | */ | |
1201 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1202 | ||
194d99c7 | 1203 | if (new_policy) { |
5a7e56a5 VK |
1204 | policy->user_policy.min = policy->min; |
1205 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1206 | |
988bed09 VK |
1207 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1208 | for_each_cpu(j, policy->related_cpus) | |
1209 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1210 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1211 | } | |
652ed95d | 1212 | |
2ed99e39 | 1213 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1214 | policy->cur = cpufreq_driver->get(policy->cpu); |
1215 | if (!policy->cur) { | |
1216 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1217 | goto out_exit_policy; |
da60ce9f VK |
1218 | } |
1219 | } | |
1220 | ||
d3916691 VK |
1221 | /* |
1222 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1223 | * frequency table present with cpufreq core. In such cases CPU might be | |
1224 | * unstable if it has to run on that frequency for long duration of time | |
1225 | * and so its better to set it to a frequency which is specified in | |
1226 | * freq-table. This also makes cpufreq stats inconsistent as | |
1227 | * cpufreq-stats would fail to register because current frequency of CPU | |
1228 | * isn't found in freq-table. | |
1229 | * | |
1230 | * Because we don't want this change to effect boot process badly, we go | |
1231 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1232 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1233 | * is initialized to zero). | |
1234 | * | |
1235 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1236 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1237 | * equal to target-freq. | |
1238 | */ | |
1239 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1240 | && has_target()) { | |
1241 | /* Are we running at unknown frequency ? */ | |
1242 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1243 | if (ret == -EINVAL) { | |
1244 | /* Warn user and fix it */ | |
1245 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1246 | __func__, policy->cpu, policy->cur); | |
1247 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1248 | CPUFREQ_RELATION_L); | |
1249 | ||
1250 | /* | |
1251 | * Reaching here after boot in a few seconds may not | |
1252 | * mean that system will remain stable at "unknown" | |
1253 | * frequency for longer duration. Hence, a BUG_ON(). | |
1254 | */ | |
1255 | BUG_ON(ret); | |
1256 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1257 | __func__, policy->cpu, policy->cur); | |
1258 | } | |
1259 | } | |
1260 | ||
a1531acd TR |
1261 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1262 | CPUFREQ_START, policy); | |
1263 | ||
194d99c7 | 1264 | if (new_policy) { |
d9612a49 | 1265 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1266 | if (ret) |
8101f997 | 1267 | goto out_exit_policy; |
fcd7af91 VK |
1268 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1269 | CPUFREQ_CREATE_POLICY, policy); | |
8ff69732 | 1270 | |
988bed09 VK |
1271 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1272 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1273 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1274 | } | |
9515f4d6 | 1275 | |
7f0fa40f VK |
1276 | ret = cpufreq_init_policy(policy); |
1277 | if (ret) { | |
1278 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1279 | __func__, cpu, ret); | |
194d99c7 RW |
1280 | /* cpufreq_policy_free() will notify based on this */ |
1281 | new_policy = false; | |
1282 | goto out_exit_policy; | |
08fd8c1c | 1283 | } |
e18f1682 | 1284 | |
4e97b631 | 1285 | up_write(&policy->rwsem); |
08fd8c1c | 1286 | |
038c5b3e | 1287 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1288 | |
7c45cf31 VK |
1289 | /* Callback for handling stuff after policy is ready */ |
1290 | if (cpufreq_driver->ready) | |
1291 | cpufreq_driver->ready(policy); | |
1292 | ||
2d06d8c4 | 1293 | pr_debug("initialization complete\n"); |
87c32271 | 1294 | |
1da177e4 LT |
1295 | return 0; |
1296 | ||
8101f997 | 1297 | out_exit_policy: |
7106e02b PB |
1298 | up_write(&policy->rwsem); |
1299 | ||
da60ce9f VK |
1300 | if (cpufreq_driver->exit) |
1301 | cpufreq_driver->exit(policy); | |
8101f997 | 1302 | out_free_policy: |
194d99c7 | 1303 | cpufreq_policy_free(policy, !new_policy); |
1da177e4 LT |
1304 | return ret; |
1305 | } | |
1306 | ||
0b275352 RW |
1307 | /** |
1308 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1309 | * @dev: CPU device. | |
1310 | * @sif: Subsystem interface structure pointer (not used) | |
1311 | */ | |
1312 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1313 | { | |
1314 | unsigned cpu = dev->id; | |
1315 | int ret; | |
1316 | ||
1317 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1318 | ||
1319 | if (cpu_online(cpu)) { | |
1320 | ret = cpufreq_online(cpu); | |
1321 | } else { | |
1322 | /* | |
1323 | * A hotplug notifier will follow and we will handle it as CPU | |
1324 | * online then. For now, just create the sysfs link, unless | |
1325 | * there is no policy or the link is already present. | |
1326 | */ | |
1327 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
1328 | ||
1329 | ret = policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus) | |
1330 | ? add_cpu_dev_symlink(policy, cpu) : 0; | |
1331 | } | |
6eed9404 | 1332 | |
1da177e4 LT |
1333 | return ret; |
1334 | } | |
1335 | ||
69cee714 | 1336 | static void cpufreq_offline(unsigned int cpu) |
1da177e4 | 1337 | { |
3a3e9e06 | 1338 | struct cpufreq_policy *policy; |
69cee714 | 1339 | int ret; |
1da177e4 | 1340 | |
b8eed8af | 1341 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1342 | |
988bed09 | 1343 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1344 | if (!policy) { |
b8eed8af | 1345 | pr_debug("%s: No cpu_data found\n", __func__); |
15c0b4d2 | 1346 | return; |
1da177e4 | 1347 | } |
1da177e4 | 1348 | |
49f18560 | 1349 | down_write(&policy->rwsem); |
9c0ebcf7 | 1350 | if (has_target()) { |
a1317e09 | 1351 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
559ed407 | 1352 | if (ret) |
3de9bdeb | 1353 | pr_err("%s: Failed to stop governor\n", __func__); |
db5f2995 | 1354 | } |
1da177e4 | 1355 | |
9591becb | 1356 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1357 | |
9591becb VK |
1358 | if (policy_is_inactive(policy)) { |
1359 | if (has_target()) | |
1360 | strncpy(policy->last_governor, policy->governor->name, | |
1361 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1362 | else |
1363 | policy->last_policy = policy->policy; | |
9591becb VK |
1364 | } else if (cpu == policy->cpu) { |
1365 | /* Nominate new CPU */ | |
1366 | policy->cpu = cpumask_any(policy->cpus); | |
1367 | } | |
084f3493 | 1368 | |
9591becb VK |
1369 | /* Start governor again for active policy */ |
1370 | if (!policy_is_inactive(policy)) { | |
1371 | if (has_target()) { | |
0a300767 | 1372 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1373 | if (ret) |
1374 | pr_err("%s: Failed to start governor\n", __func__); | |
1375 | } | |
cedb70af | 1376 | |
49f18560 | 1377 | goto unlock; |
cedb70af SB |
1378 | } |
1379 | ||
69cee714 VK |
1380 | if (cpufreq_driver->stop_cpu) |
1381 | cpufreq_driver->stop_cpu(policy); | |
87549141 VK |
1382 | |
1383 | /* If cpu is last user of policy, free policy */ | |
1384 | if (has_target()) { | |
b7898fda | 1385 | ret = cpufreq_exit_governor(policy); |
559ed407 | 1386 | if (ret) |
87549141 | 1387 | pr_err("%s: Failed to exit governor\n", __func__); |
27ecddc2 | 1388 | } |
1da177e4 | 1389 | |
87549141 VK |
1390 | /* |
1391 | * Perform the ->exit() even during light-weight tear-down, | |
1392 | * since this is a core component, and is essential for the | |
1393 | * subsequent light-weight ->init() to succeed. | |
1394 | */ | |
55582bcc | 1395 | if (cpufreq_driver->exit) { |
87549141 | 1396 | cpufreq_driver->exit(policy); |
55582bcc SP |
1397 | policy->freq_table = NULL; |
1398 | } | |
49f18560 VK |
1399 | |
1400 | unlock: | |
1401 | up_write(&policy->rwsem); | |
1da177e4 LT |
1402 | } |
1403 | ||
cedb70af | 1404 | /** |
27a862e9 | 1405 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1406 | * |
1407 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1408 | */ |
71db87ba | 1409 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1410 | { |
8a25a2fd | 1411 | unsigned int cpu = dev->id; |
559ed407 | 1412 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1413 | |
559ed407 | 1414 | if (!policy) |
1af115d6 | 1415 | return; |
87549141 | 1416 | |
69cee714 VK |
1417 | if (cpu_online(cpu)) |
1418 | cpufreq_offline(cpu); | |
87549141 | 1419 | |
559ed407 | 1420 | cpumask_clear_cpu(cpu, policy->real_cpus); |
f344dae0 | 1421 | remove_cpu_dev_symlink(policy, cpu); |
87549141 | 1422 | |
f344dae0 | 1423 | if (cpumask_empty(policy->real_cpus)) |
3654c5cc | 1424 | cpufreq_policy_free(policy, true); |
5a01f2e8 VP |
1425 | } |
1426 | ||
1da177e4 | 1427 | /** |
bb176f7d VK |
1428 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1429 | * in deep trouble. | |
a1e1dc41 | 1430 | * @policy: policy managing CPUs |
1da177e4 LT |
1431 | * @new_freq: CPU frequency the CPU actually runs at |
1432 | * | |
29464f28 DJ |
1433 | * We adjust to current frequency first, and need to clean up later. |
1434 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1435 | */ |
a1e1dc41 | 1436 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1437 | unsigned int new_freq) |
1da177e4 LT |
1438 | { |
1439 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1440 | |
e837f9b5 | 1441 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1442 | policy->cur, new_freq); |
1da177e4 | 1443 | |
a1e1dc41 | 1444 | freqs.old = policy->cur; |
1da177e4 | 1445 | freqs.new = new_freq; |
b43a7ffb | 1446 | |
8fec051e VK |
1447 | cpufreq_freq_transition_begin(policy, &freqs); |
1448 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1449 | } |
1450 | ||
32ee8c3e | 1451 | /** |
4ab70df4 | 1452 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1453 | * @cpu: CPU number |
1454 | * | |
1455 | * This is the last known freq, without actually getting it from the driver. | |
1456 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1457 | */ | |
1458 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1459 | { | |
9e21ba8b | 1460 | struct cpufreq_policy *policy; |
e08f5f5b | 1461 | unsigned int ret_freq = 0; |
c75361c0 | 1462 | unsigned long flags; |
95235ca2 | 1463 | |
c75361c0 RC |
1464 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1465 | ||
1466 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1467 | ret_freq = cpufreq_driver->get(cpu); | |
1468 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1469 | return ret_freq; | |
1470 | } | |
1471 | ||
1472 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1473 | |
1474 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1475 | if (policy) { |
e08f5f5b | 1476 | ret_freq = policy->cur; |
95235ca2 VP |
1477 | cpufreq_cpu_put(policy); |
1478 | } | |
1479 | ||
4d34a67d | 1480 | return ret_freq; |
95235ca2 VP |
1481 | } |
1482 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1483 | ||
3d737108 JB |
1484 | /** |
1485 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1486 | * @cpu: CPU number | |
1487 | * | |
1488 | * Just return the max possible frequency for a given CPU. | |
1489 | */ | |
1490 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1491 | { | |
1492 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1493 | unsigned int ret_freq = 0; | |
1494 | ||
1495 | if (policy) { | |
1496 | ret_freq = policy->max; | |
1497 | cpufreq_cpu_put(policy); | |
1498 | } | |
1499 | ||
1500 | return ret_freq; | |
1501 | } | |
1502 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1503 | ||
d92d50a4 | 1504 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1505 | { |
e08f5f5b | 1506 | unsigned int ret_freq = 0; |
5800043b | 1507 | |
1c3d85dd | 1508 | if (!cpufreq_driver->get) |
4d34a67d | 1509 | return ret_freq; |
1da177e4 | 1510 | |
d92d50a4 | 1511 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1512 | |
b7898fda RW |
1513 | /* |
1514 | * Updating inactive policies is invalid, so avoid doing that. Also | |
1515 | * if fast frequency switching is used with the given policy, the check | |
1516 | * against policy->cur is pointless, so skip it in that case too. | |
1517 | */ | |
1518 | if (unlikely(policy_is_inactive(policy)) || policy->fast_switch_enabled) | |
11e584cf VK |
1519 | return ret_freq; |
1520 | ||
e08f5f5b | 1521 | if (ret_freq && policy->cur && |
1c3d85dd | 1522 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1523 | /* verify no discrepancy between actual and |
1524 | saved value exists */ | |
1525 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1526 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1527 | schedule_work(&policy->update); |
1528 | } | |
1529 | } | |
1530 | ||
4d34a67d | 1531 | return ret_freq; |
5a01f2e8 | 1532 | } |
1da177e4 | 1533 | |
5a01f2e8 VP |
1534 | /** |
1535 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1536 | * @cpu: CPU number | |
1537 | * | |
1538 | * Get the CPU current (static) CPU frequency | |
1539 | */ | |
1540 | unsigned int cpufreq_get(unsigned int cpu) | |
1541 | { | |
999976e0 | 1542 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1543 | unsigned int ret_freq = 0; |
5a01f2e8 | 1544 | |
999976e0 AP |
1545 | if (policy) { |
1546 | down_read(&policy->rwsem); | |
d92d50a4 | 1547 | ret_freq = __cpufreq_get(policy); |
999976e0 | 1548 | up_read(&policy->rwsem); |
5a01f2e8 | 1549 | |
999976e0 AP |
1550 | cpufreq_cpu_put(policy); |
1551 | } | |
6eed9404 | 1552 | |
4d34a67d | 1553 | return ret_freq; |
1da177e4 LT |
1554 | } |
1555 | EXPORT_SYMBOL(cpufreq_get); | |
1556 | ||
999f5729 RW |
1557 | static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy) |
1558 | { | |
1559 | unsigned int new_freq; | |
1560 | ||
1561 | new_freq = cpufreq_driver->get(policy->cpu); | |
1562 | if (!new_freq) | |
1563 | return 0; | |
1564 | ||
1565 | if (!policy->cur) { | |
1566 | pr_debug("cpufreq: Driver did not initialize current freq\n"); | |
1567 | policy->cur = new_freq; | |
1568 | } else if (policy->cur != new_freq && has_target()) { | |
1569 | cpufreq_out_of_sync(policy, new_freq); | |
1570 | } | |
1571 | ||
1572 | return new_freq; | |
1573 | } | |
1574 | ||
8a25a2fd KS |
1575 | static struct subsys_interface cpufreq_interface = { |
1576 | .name = "cpufreq", | |
1577 | .subsys = &cpu_subsys, | |
1578 | .add_dev = cpufreq_add_dev, | |
1579 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1580 | }; |
1581 | ||
e28867ea VK |
1582 | /* |
1583 | * In case platform wants some specific frequency to be configured | |
1584 | * during suspend.. | |
1585 | */ | |
1586 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1587 | { | |
1588 | int ret; | |
1589 | ||
1590 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1591 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1592 | return 0; | |
e28867ea VK |
1593 | } |
1594 | ||
1595 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1596 | policy->suspend_freq); | |
1597 | ||
1598 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1599 | CPUFREQ_RELATION_H); | |
1600 | if (ret) | |
1601 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1602 | __func__, policy->suspend_freq, ret); | |
1603 | ||
1604 | return ret; | |
1605 | } | |
1606 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1607 | ||
42d4dc3f | 1608 | /** |
2f0aea93 | 1609 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1610 | * |
2f0aea93 VK |
1611 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1612 | * as some platforms can't change frequency after this point in suspend cycle. | |
1613 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1614 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1615 | */ |
2f0aea93 | 1616 | void cpufreq_suspend(void) |
42d4dc3f | 1617 | { |
3a3e9e06 | 1618 | struct cpufreq_policy *policy; |
49f18560 | 1619 | int ret; |
42d4dc3f | 1620 | |
2f0aea93 VK |
1621 | if (!cpufreq_driver) |
1622 | return; | |
42d4dc3f | 1623 | |
2f0aea93 | 1624 | if (!has_target()) |
b1b12bab | 1625 | goto suspend; |
42d4dc3f | 1626 | |
2f0aea93 VK |
1627 | pr_debug("%s: Suspending Governors\n", __func__); |
1628 | ||
f963735a | 1629 | for_each_active_policy(policy) { |
49f18560 | 1630 | down_write(&policy->rwsem); |
a1317e09 | 1631 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
49f18560 VK |
1632 | up_write(&policy->rwsem); |
1633 | ||
1634 | if (ret) | |
2f0aea93 VK |
1635 | pr_err("%s: Failed to stop governor for policy: %p\n", |
1636 | __func__, policy); | |
1637 | else if (cpufreq_driver->suspend | |
1638 | && cpufreq_driver->suspend(policy)) | |
1639 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1640 | policy); | |
42d4dc3f | 1641 | } |
b1b12bab VK |
1642 | |
1643 | suspend: | |
1644 | cpufreq_suspended = true; | |
42d4dc3f BH |
1645 | } |
1646 | ||
1da177e4 | 1647 | /** |
2f0aea93 | 1648 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1649 | * |
2f0aea93 VK |
1650 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1651 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1652 | */ |
2f0aea93 | 1653 | void cpufreq_resume(void) |
1da177e4 | 1654 | { |
3a3e9e06 | 1655 | struct cpufreq_policy *policy; |
49f18560 | 1656 | int ret; |
1da177e4 | 1657 | |
2f0aea93 VK |
1658 | if (!cpufreq_driver) |
1659 | return; | |
1da177e4 | 1660 | |
8e30444e LT |
1661 | cpufreq_suspended = false; |
1662 | ||
2f0aea93 | 1663 | if (!has_target()) |
e00e56df | 1664 | return; |
1da177e4 | 1665 | |
2f0aea93 | 1666 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1667 | |
f963735a | 1668 | for_each_active_policy(policy) { |
49f18560 | 1669 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1670 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1671 | policy); | |
49f18560 VK |
1672 | } else { |
1673 | down_write(&policy->rwsem); | |
0a300767 | 1674 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1675 | up_write(&policy->rwsem); |
1676 | ||
1677 | if (ret) | |
1678 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1679 | __func__, policy); | |
1680 | } | |
2f0aea93 VK |
1681 | } |
1682 | } | |
1da177e4 | 1683 | |
9d95046e BP |
1684 | /** |
1685 | * cpufreq_get_current_driver - return current driver's name | |
1686 | * | |
1687 | * Return the name string of the currently loaded cpufreq driver | |
1688 | * or NULL, if none. | |
1689 | */ | |
1690 | const char *cpufreq_get_current_driver(void) | |
1691 | { | |
1c3d85dd RW |
1692 | if (cpufreq_driver) |
1693 | return cpufreq_driver->name; | |
1694 | ||
1695 | return NULL; | |
9d95046e BP |
1696 | } |
1697 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1698 | |
51315cdf TP |
1699 | /** |
1700 | * cpufreq_get_driver_data - return current driver data | |
1701 | * | |
1702 | * Return the private data of the currently loaded cpufreq | |
1703 | * driver, or NULL if no cpufreq driver is loaded. | |
1704 | */ | |
1705 | void *cpufreq_get_driver_data(void) | |
1706 | { | |
1707 | if (cpufreq_driver) | |
1708 | return cpufreq_driver->driver_data; | |
1709 | ||
1710 | return NULL; | |
1711 | } | |
1712 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1713 | ||
1da177e4 LT |
1714 | /********************************************************************* |
1715 | * NOTIFIER LISTS INTERFACE * | |
1716 | *********************************************************************/ | |
1717 | ||
1718 | /** | |
1719 | * cpufreq_register_notifier - register a driver with cpufreq | |
1720 | * @nb: notifier function to register | |
1721 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1722 | * | |
32ee8c3e | 1723 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1724 | * are notified about clock rate changes (once before and once after |
1725 | * the transition), or a list of drivers that are notified about | |
1726 | * changes in cpufreq policy. | |
1727 | * | |
1728 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1729 | * blocking_notifier_chain_register. |
1da177e4 LT |
1730 | */ |
1731 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1732 | { | |
1733 | int ret; | |
1734 | ||
d5aaffa9 DB |
1735 | if (cpufreq_disabled()) |
1736 | return -EINVAL; | |
1737 | ||
74212ca4 CEB |
1738 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1739 | ||
1da177e4 LT |
1740 | switch (list) { |
1741 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1742 | mutex_lock(&cpufreq_fast_switch_lock); |
1743 | ||
1744 | if (cpufreq_fast_switch_count > 0) { | |
1745 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1746 | return -EBUSY; | |
1747 | } | |
b4dfdbb3 | 1748 | ret = srcu_notifier_chain_register( |
e041c683 | 1749 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1750 | if (!ret) |
1751 | cpufreq_fast_switch_count--; | |
1752 | ||
1753 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1754 | break; |
1755 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1756 | ret = blocking_notifier_chain_register( |
1757 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1758 | break; |
1759 | default: | |
1760 | ret = -EINVAL; | |
1761 | } | |
1da177e4 LT |
1762 | |
1763 | return ret; | |
1764 | } | |
1765 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1766 | ||
1da177e4 LT |
1767 | /** |
1768 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1769 | * @nb: notifier block to be unregistered | |
bb176f7d | 1770 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1771 | * |
1772 | * Remove a driver from the CPU frequency notifier list. | |
1773 | * | |
1774 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1775 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1776 | */ |
1777 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1778 | { | |
1779 | int ret; | |
1780 | ||
d5aaffa9 DB |
1781 | if (cpufreq_disabled()) |
1782 | return -EINVAL; | |
1783 | ||
1da177e4 LT |
1784 | switch (list) { |
1785 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1786 | mutex_lock(&cpufreq_fast_switch_lock); |
1787 | ||
b4dfdbb3 | 1788 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1789 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1790 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
1791 | cpufreq_fast_switch_count++; | |
1792 | ||
1793 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1794 | break; |
1795 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1796 | ret = blocking_notifier_chain_unregister( |
1797 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1798 | break; |
1799 | default: | |
1800 | ret = -EINVAL; | |
1801 | } | |
1da177e4 LT |
1802 | |
1803 | return ret; | |
1804 | } | |
1805 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1806 | ||
1807 | ||
1808 | /********************************************************************* | |
1809 | * GOVERNORS * | |
1810 | *********************************************************************/ | |
1811 | ||
b7898fda RW |
1812 | /** |
1813 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
1814 | * @policy: cpufreq policy to switch the frequency for. | |
1815 | * @target_freq: New frequency to set (may be approximate). | |
1816 | * | |
1817 | * Carry out a fast frequency switch without sleeping. | |
1818 | * | |
1819 | * The driver's ->fast_switch() callback invoked by this function must be | |
1820 | * suitable for being called from within RCU-sched read-side critical sections | |
1821 | * and it is expected to select the minimum available frequency greater than or | |
1822 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
1823 | * | |
1824 | * This function must not be called if policy->fast_switch_enabled is unset. | |
1825 | * | |
1826 | * Governors calling this function must guarantee that it will never be invoked | |
1827 | * twice in parallel for the same policy and that it will never be called in | |
1828 | * parallel with either ->target() or ->target_index() for the same policy. | |
1829 | * | |
1830 | * If CPUFREQ_ENTRY_INVALID is returned by the driver's ->fast_switch() | |
1831 | * callback to indicate an error condition, the hardware configuration must be | |
1832 | * preserved. | |
1833 | */ | |
1834 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
1835 | unsigned int target_freq) | |
1836 | { | |
1837 | clamp_val(target_freq, policy->min, policy->max); | |
1838 | ||
1839 | return cpufreq_driver->fast_switch(policy, target_freq); | |
1840 | } | |
1841 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
1842 | ||
1c03a2d0 VK |
1843 | /* Must set freqs->new to intermediate frequency */ |
1844 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1845 | struct cpufreq_freqs *freqs, int index) | |
1846 | { | |
1847 | int ret; | |
1848 | ||
1849 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1850 | ||
1851 | /* We don't need to switch to intermediate freq */ | |
1852 | if (!freqs->new) | |
1853 | return 0; | |
1854 | ||
1855 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1856 | __func__, policy->cpu, freqs->old, freqs->new); | |
1857 | ||
1858 | cpufreq_freq_transition_begin(policy, freqs); | |
1859 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1860 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1861 | ||
1862 | if (ret) | |
1863 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1864 | __func__, ret); | |
1865 | ||
1866 | return ret; | |
1867 | } | |
1868 | ||
8d65775d VK |
1869 | static int __target_index(struct cpufreq_policy *policy, |
1870 | struct cpufreq_frequency_table *freq_table, int index) | |
1871 | { | |
1c03a2d0 VK |
1872 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1873 | unsigned int intermediate_freq = 0; | |
8d65775d VK |
1874 | int retval = -EINVAL; |
1875 | bool notify; | |
1876 | ||
1877 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
8d65775d | 1878 | if (notify) { |
1c03a2d0 VK |
1879 | /* Handle switching to intermediate frequency */ |
1880 | if (cpufreq_driver->get_intermediate) { | |
1881 | retval = __target_intermediate(policy, &freqs, index); | |
1882 | if (retval) | |
1883 | return retval; | |
1884 | ||
1885 | intermediate_freq = freqs.new; | |
1886 | /* Set old freq to intermediate */ | |
1887 | if (intermediate_freq) | |
1888 | freqs.old = freqs.new; | |
1889 | } | |
8d65775d | 1890 | |
1c03a2d0 | 1891 | freqs.new = freq_table[index].frequency; |
8d65775d VK |
1892 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1893 | __func__, policy->cpu, freqs.old, freqs.new); | |
1894 | ||
1895 | cpufreq_freq_transition_begin(policy, &freqs); | |
1896 | } | |
1897 | ||
1898 | retval = cpufreq_driver->target_index(policy, index); | |
1899 | if (retval) | |
1900 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1901 | retval); | |
1902 | ||
1c03a2d0 | 1903 | if (notify) { |
8d65775d VK |
1904 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1905 | ||
1c03a2d0 VK |
1906 | /* |
1907 | * Failed after setting to intermediate freq? Driver should have | |
1908 | * reverted back to initial frequency and so should we. Check | |
1909 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1910 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1911 | */ |
1912 | if (unlikely(retval && intermediate_freq)) { | |
1913 | freqs.old = intermediate_freq; | |
1914 | freqs.new = policy->restore_freq; | |
1915 | cpufreq_freq_transition_begin(policy, &freqs); | |
1916 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1917 | } | |
1918 | } | |
1919 | ||
8d65775d VK |
1920 | return retval; |
1921 | } | |
1922 | ||
1da177e4 LT |
1923 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1924 | unsigned int target_freq, | |
1925 | unsigned int relation) | |
1926 | { | |
7249924e | 1927 | unsigned int old_target_freq = target_freq; |
6019d23a RW |
1928 | struct cpufreq_frequency_table *freq_table; |
1929 | int index, retval; | |
c32b6b8e | 1930 | |
a7b422cd KRW |
1931 | if (cpufreq_disabled()) |
1932 | return -ENODEV; | |
1933 | ||
7249924e VK |
1934 | /* Make sure that target_freq is within supported range */ |
1935 | if (target_freq > policy->max) | |
1936 | target_freq = policy->max; | |
1937 | if (target_freq < policy->min) | |
1938 | target_freq = policy->min; | |
1939 | ||
1940 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1941 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1942 | |
9c0ebcf7 VK |
1943 | /* |
1944 | * This might look like a redundant call as we are checking it again | |
1945 | * after finding index. But it is left intentionally for cases where | |
1946 | * exactly same freq is called again and so we can save on few function | |
1947 | * calls. | |
1948 | */ | |
5a1c0228 VK |
1949 | if (target_freq == policy->cur) |
1950 | return 0; | |
1951 | ||
1c03a2d0 VK |
1952 | /* Save last value to restore later on errors */ |
1953 | policy->restore_freq = policy->cur; | |
1954 | ||
1c3d85dd | 1955 | if (cpufreq_driver->target) |
6019d23a | 1956 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 1957 | |
6019d23a RW |
1958 | if (!cpufreq_driver->target_index) |
1959 | return -EINVAL; | |
9c0ebcf7 | 1960 | |
6019d23a RW |
1961 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
1962 | if (unlikely(!freq_table)) { | |
1963 | pr_err("%s: Unable to find freq_table\n", __func__); | |
1964 | return -EINVAL; | |
1965 | } | |
d4019f0a | 1966 | |
6019d23a RW |
1967 | retval = cpufreq_frequency_table_target(policy, freq_table, target_freq, |
1968 | relation, &index); | |
1969 | if (unlikely(retval)) { | |
1970 | pr_err("%s: Unable to find matching freq\n", __func__); | |
1971 | return retval; | |
9c0ebcf7 VK |
1972 | } |
1973 | ||
6019d23a RW |
1974 | if (freq_table[index].frequency == policy->cur) |
1975 | return 0; | |
1976 | ||
1977 | return __target_index(policy, freq_table, index); | |
1da177e4 LT |
1978 | } |
1979 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1980 | ||
1da177e4 LT |
1981 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1982 | unsigned int target_freq, | |
1983 | unsigned int relation) | |
1984 | { | |
f1829e4a | 1985 | int ret = -EINVAL; |
1da177e4 | 1986 | |
ad7722da | 1987 | down_write(&policy->rwsem); |
1da177e4 LT |
1988 | |
1989 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1990 | ||
ad7722da | 1991 | up_write(&policy->rwsem); |
1da177e4 | 1992 | |
1da177e4 LT |
1993 | return ret; |
1994 | } | |
1995 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1996 | ||
de1df26b RW |
1997 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
1998 | { | |
1999 | return NULL; | |
2000 | } | |
2001 | ||
a1317e09 | 2002 | static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event) |
1da177e4 | 2003 | { |
cc993cab | 2004 | int ret; |
6afde10c | 2005 | |
2f0aea93 VK |
2006 | /* Don't start any governor operations if we are entering suspend */ |
2007 | if (cpufreq_suspended) | |
2008 | return 0; | |
cb57720b EZ |
2009 | /* |
2010 | * Governor might not be initiated here if ACPI _PPC changed | |
2011 | * notification happened, so check it. | |
2012 | */ | |
2013 | if (!policy->governor) | |
2014 | return -EINVAL; | |
2f0aea93 | 2015 | |
1c256245 TR |
2016 | if (policy->governor->max_transition_latency && |
2017 | policy->cpuinfo.transition_latency > | |
2018 | policy->governor->max_transition_latency) { | |
de1df26b RW |
2019 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2020 | ||
2021 | if (gov) { | |
e837f9b5 JP |
2022 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
2023 | policy->governor->name, gov->name); | |
6afde10c | 2024 | policy->governor = gov; |
de1df26b RW |
2025 | } else { |
2026 | return -EINVAL; | |
6afde10c | 2027 | } |
1c256245 | 2028 | } |
1da177e4 | 2029 | |
fe492f3f VK |
2030 | if (event == CPUFREQ_GOV_POLICY_INIT) |
2031 | if (!try_module_get(policy->governor->owner)) | |
2032 | return -EINVAL; | |
1da177e4 | 2033 | |
63431f78 | 2034 | pr_debug("%s: for CPU %u, event %u\n", __func__, policy->cpu, event); |
95731ebb | 2035 | |
1da177e4 LT |
2036 | ret = policy->governor->governor(policy, event); |
2037 | ||
4d5dcc42 VK |
2038 | if (!ret) { |
2039 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
2040 | policy->governor->initialized++; | |
2041 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
2042 | policy->governor->initialized--; | |
2043 | } | |
b394058f | 2044 | |
fe492f3f VK |
2045 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
2046 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
2047 | module_put(policy->governor->owner); |
2048 | ||
2049 | return ret; | |
2050 | } | |
2051 | ||
0a300767 RW |
2052 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
2053 | { | |
2054 | int ret; | |
2055 | ||
3bbf8fe3 RW |
2056 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) |
2057 | cpufreq_update_current_freq(policy); | |
2058 | ||
0a300767 RW |
2059 | ret = cpufreq_governor(policy, CPUFREQ_GOV_START); |
2060 | return ret ? ret : cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2061 | } | |
2062 | ||
b7898fda RW |
2063 | static int cpufreq_exit_governor(struct cpufreq_policy *policy) |
2064 | { | |
2065 | cpufreq_disable_fast_switch(policy); | |
2066 | return cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
2067 | } | |
2068 | ||
1da177e4 LT |
2069 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2070 | { | |
3bcb09a3 | 2071 | int err; |
1da177e4 LT |
2072 | |
2073 | if (!governor) | |
2074 | return -EINVAL; | |
2075 | ||
a7b422cd KRW |
2076 | if (cpufreq_disabled()) |
2077 | return -ENODEV; | |
2078 | ||
3fc54d37 | 2079 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2080 | |
b394058f | 2081 | governor->initialized = 0; |
3bcb09a3 | 2082 | err = -EBUSY; |
42f91fa1 | 2083 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2084 | err = 0; |
2085 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2086 | } |
1da177e4 | 2087 | |
32ee8c3e | 2088 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2089 | return err; |
1da177e4 LT |
2090 | } |
2091 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2092 | ||
1da177e4 LT |
2093 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2094 | { | |
4573237b VK |
2095 | struct cpufreq_policy *policy; |
2096 | unsigned long flags; | |
90e41bac | 2097 | |
1da177e4 LT |
2098 | if (!governor) |
2099 | return; | |
2100 | ||
a7b422cd KRW |
2101 | if (cpufreq_disabled()) |
2102 | return; | |
2103 | ||
4573237b VK |
2104 | /* clear last_governor for all inactive policies */ |
2105 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2106 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2107 | if (!strcmp(policy->last_governor, governor->name)) { |
2108 | policy->governor = NULL; | |
4573237b | 2109 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2110 | } |
90e41bac | 2111 | } |
4573237b | 2112 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2113 | |
3fc54d37 | 2114 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2115 | list_del(&governor->governor_list); |
3fc54d37 | 2116 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2117 | return; |
2118 | } | |
2119 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2120 | ||
2121 | ||
1da177e4 LT |
2122 | /********************************************************************* |
2123 | * POLICY INTERFACE * | |
2124 | *********************************************************************/ | |
2125 | ||
2126 | /** | |
2127 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2128 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2129 | * is written | |
1da177e4 LT |
2130 | * |
2131 | * Reads the current cpufreq policy. | |
2132 | */ | |
2133 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2134 | { | |
2135 | struct cpufreq_policy *cpu_policy; | |
2136 | if (!policy) | |
2137 | return -EINVAL; | |
2138 | ||
2139 | cpu_policy = cpufreq_cpu_get(cpu); | |
2140 | if (!cpu_policy) | |
2141 | return -EINVAL; | |
2142 | ||
d5b73cd8 | 2143 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2144 | |
2145 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2146 | return 0; |
2147 | } | |
2148 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2149 | ||
153d7f3f | 2150 | /* |
037ce839 VK |
2151 | * policy : current policy. |
2152 | * new_policy: policy to be set. | |
153d7f3f | 2153 | */ |
037ce839 | 2154 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2155 | struct cpufreq_policy *new_policy) |
1da177e4 | 2156 | { |
d9a789c7 RW |
2157 | struct cpufreq_governor *old_gov; |
2158 | int ret; | |
1da177e4 | 2159 | |
e837f9b5 JP |
2160 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2161 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2162 | |
d5b73cd8 | 2163 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2164 | |
fba9573b PX |
2165 | /* |
2166 | * This check works well when we store new min/max freq attributes, | |
2167 | * because new_policy is a copy of policy with one field updated. | |
2168 | */ | |
2169 | if (new_policy->min > new_policy->max) | |
d9a789c7 | 2170 | return -EINVAL; |
9c9a43ed | 2171 | |
1da177e4 | 2172 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2173 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2174 | if (ret) |
d9a789c7 | 2175 | return ret; |
1da177e4 | 2176 | |
1da177e4 | 2177 | /* adjust if necessary - all reasons */ |
e041c683 | 2178 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2179 | CPUFREQ_ADJUST, new_policy); |
1da177e4 | 2180 | |
bb176f7d VK |
2181 | /* |
2182 | * verify the cpu speed can be set within this limit, which might be | |
2183 | * different to the first one | |
2184 | */ | |
3a3e9e06 | 2185 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2186 | if (ret) |
d9a789c7 | 2187 | return ret; |
1da177e4 LT |
2188 | |
2189 | /* notification of the new policy */ | |
e041c683 | 2190 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2191 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2192 | |
3a3e9e06 VK |
2193 | policy->min = new_policy->min; |
2194 | policy->max = new_policy->max; | |
1da177e4 | 2195 | |
2d06d8c4 | 2196 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2197 | policy->min, policy->max); |
1da177e4 | 2198 | |
1c3d85dd | 2199 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2200 | policy->policy = new_policy->policy; |
2d06d8c4 | 2201 | pr_debug("setting range\n"); |
d9a789c7 RW |
2202 | return cpufreq_driver->setpolicy(new_policy); |
2203 | } | |
1da177e4 | 2204 | |
0a300767 RW |
2205 | if (new_policy->governor == policy->governor) { |
2206 | pr_debug("cpufreq: governor limits update\n"); | |
2207 | return cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2208 | } | |
7bd353a9 | 2209 | |
d9a789c7 RW |
2210 | pr_debug("governor switch\n"); |
2211 | ||
2212 | /* save old, working values */ | |
2213 | old_gov = policy->governor; | |
2214 | /* end old governor */ | |
2215 | if (old_gov) { | |
a1317e09 | 2216 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
4bc384ae VK |
2217 | if (ret) { |
2218 | /* This can happen due to race with other operations */ | |
2219 | pr_debug("%s: Failed to Stop Governor: %s (%d)\n", | |
2220 | __func__, old_gov->name, ret); | |
2221 | return ret; | |
2222 | } | |
2223 | ||
b7898fda | 2224 | ret = cpufreq_exit_governor(policy); |
4bc384ae VK |
2225 | if (ret) { |
2226 | pr_err("%s: Failed to Exit Governor: %s (%d)\n", | |
2227 | __func__, old_gov->name, ret); | |
2228 | return ret; | |
2229 | } | |
1da177e4 LT |
2230 | } |
2231 | ||
d9a789c7 RW |
2232 | /* start new governor */ |
2233 | policy->governor = new_policy->governor; | |
a1317e09 | 2234 | ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); |
4bc384ae | 2235 | if (!ret) { |
0a300767 RW |
2236 | ret = cpufreq_start_governor(policy); |
2237 | if (!ret) { | |
2238 | pr_debug("cpufreq: governor change\n"); | |
2239 | return 0; | |
2240 | } | |
b7898fda | 2241 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2242 | } |
2243 | ||
2244 | /* new governor failed, so re-start old one */ | |
2245 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2246 | if (old_gov) { | |
2247 | policy->governor = old_gov; | |
a1317e09 | 2248 | if (cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) |
4bc384ae VK |
2249 | policy->governor = NULL; |
2250 | else | |
0a300767 | 2251 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2252 | } |
2253 | ||
4bc384ae | 2254 | return ret; |
1da177e4 LT |
2255 | } |
2256 | ||
1da177e4 LT |
2257 | /** |
2258 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2259 | * @cpu: CPU which shall be re-evaluated | |
2260 | * | |
25985edc | 2261 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2262 | * at different times. |
2263 | */ | |
2264 | int cpufreq_update_policy(unsigned int cpu) | |
2265 | { | |
3a3e9e06 VK |
2266 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2267 | struct cpufreq_policy new_policy; | |
f1829e4a | 2268 | int ret; |
1da177e4 | 2269 | |
fefa8ff8 AP |
2270 | if (!policy) |
2271 | return -ENODEV; | |
1da177e4 | 2272 | |
ad7722da | 2273 | down_write(&policy->rwsem); |
1da177e4 | 2274 | |
2d06d8c4 | 2275 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2276 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2277 | new_policy.min = policy->user_policy.min; |
2278 | new_policy.max = policy->user_policy.max; | |
1da177e4 | 2279 | |
bb176f7d VK |
2280 | /* |
2281 | * BIOS might change freq behind our back | |
2282 | * -> ask driver for current freq and notify governors about a change | |
2283 | */ | |
2ed99e39 | 2284 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
999f5729 | 2285 | new_policy.cur = cpufreq_update_current_freq(policy); |
bd0fa9bb VK |
2286 | if (WARN_ON(!new_policy.cur)) { |
2287 | ret = -EIO; | |
fefa8ff8 | 2288 | goto unlock; |
bd0fa9bb | 2289 | } |
0961dd0d TR |
2290 | } |
2291 | ||
037ce839 | 2292 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2293 | |
fefa8ff8 | 2294 | unlock: |
ad7722da | 2295 | up_write(&policy->rwsem); |
5a01f2e8 | 2296 | |
3a3e9e06 | 2297 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2298 | return ret; |
2299 | } | |
2300 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2301 | ||
2760984f | 2302 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2303 | unsigned long action, void *hcpu) |
2304 | { | |
2305 | unsigned int cpu = (unsigned long)hcpu; | |
c32b6b8e | 2306 | |
0b275352 RW |
2307 | switch (action & ~CPU_TASKS_FROZEN) { |
2308 | case CPU_ONLINE: | |
2309 | cpufreq_online(cpu); | |
2310 | break; | |
5302c3fb | 2311 | |
0b275352 | 2312 | case CPU_DOWN_PREPARE: |
69cee714 | 2313 | cpufreq_offline(cpu); |
0b275352 | 2314 | break; |
5302c3fb | 2315 | |
0b275352 RW |
2316 | case CPU_DOWN_FAILED: |
2317 | cpufreq_online(cpu); | |
2318 | break; | |
c32b6b8e AR |
2319 | } |
2320 | return NOTIFY_OK; | |
2321 | } | |
2322 | ||
9c36f746 | 2323 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2324 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2325 | }; |
1da177e4 | 2326 | |
6f19efc0 LM |
2327 | /********************************************************************* |
2328 | * BOOST * | |
2329 | *********************************************************************/ | |
2330 | static int cpufreq_boost_set_sw(int state) | |
2331 | { | |
2332 | struct cpufreq_frequency_table *freq_table; | |
2333 | struct cpufreq_policy *policy; | |
2334 | int ret = -EINVAL; | |
2335 | ||
f963735a | 2336 | for_each_active_policy(policy) { |
6f19efc0 LM |
2337 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2338 | if (freq_table) { | |
2339 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2340 | freq_table); | |
2341 | if (ret) { | |
2342 | pr_err("%s: Policy frequency update failed\n", | |
2343 | __func__); | |
2344 | break; | |
2345 | } | |
49f18560 VK |
2346 | |
2347 | down_write(&policy->rwsem); | |
6f19efc0 | 2348 | policy->user_policy.max = policy->max; |
a1317e09 | 2349 | cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
49f18560 | 2350 | up_write(&policy->rwsem); |
6f19efc0 LM |
2351 | } |
2352 | } | |
2353 | ||
2354 | return ret; | |
2355 | } | |
2356 | ||
2357 | int cpufreq_boost_trigger_state(int state) | |
2358 | { | |
2359 | unsigned long flags; | |
2360 | int ret = 0; | |
2361 | ||
2362 | if (cpufreq_driver->boost_enabled == state) | |
2363 | return 0; | |
2364 | ||
2365 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2366 | cpufreq_driver->boost_enabled = state; | |
2367 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2368 | ||
2369 | ret = cpufreq_driver->set_boost(state); | |
2370 | if (ret) { | |
2371 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2372 | cpufreq_driver->boost_enabled = !state; | |
2373 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2374 | ||
e837f9b5 JP |
2375 | pr_err("%s: Cannot %s BOOST\n", |
2376 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2377 | } |
2378 | ||
2379 | return ret; | |
2380 | } | |
2381 | ||
41669da0 | 2382 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2383 | { |
7a6c79f2 | 2384 | return likely(cpufreq_driver) && cpufreq_driver->set_boost; |
6f19efc0 | 2385 | } |
6f19efc0 | 2386 | |
44139ed4 VK |
2387 | static int create_boost_sysfs_file(void) |
2388 | { | |
2389 | int ret; | |
2390 | ||
c82bd444 | 2391 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2392 | if (ret) |
2393 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2394 | __func__); | |
2395 | ||
2396 | return ret; | |
2397 | } | |
2398 | ||
2399 | static void remove_boost_sysfs_file(void) | |
2400 | { | |
2401 | if (cpufreq_boost_supported()) | |
c82bd444 | 2402 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2403 | } |
2404 | ||
2405 | int cpufreq_enable_boost_support(void) | |
2406 | { | |
2407 | if (!cpufreq_driver) | |
2408 | return -EINVAL; | |
2409 | ||
2410 | if (cpufreq_boost_supported()) | |
2411 | return 0; | |
2412 | ||
7a6c79f2 | 2413 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2414 | |
2415 | /* This will get removed on driver unregister */ | |
2416 | return create_boost_sysfs_file(); | |
2417 | } | |
2418 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2419 | ||
6f19efc0 LM |
2420 | int cpufreq_boost_enabled(void) |
2421 | { | |
2422 | return cpufreq_driver->boost_enabled; | |
2423 | } | |
2424 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2425 | ||
1da177e4 LT |
2426 | /********************************************************************* |
2427 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2428 | *********************************************************************/ | |
2429 | ||
2430 | /** | |
2431 | * cpufreq_register_driver - register a CPU Frequency driver | |
2432 | * @driver_data: A struct cpufreq_driver containing the values# | |
2433 | * submitted by the CPU Frequency driver. | |
2434 | * | |
bb176f7d | 2435 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2436 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2437 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2438 | * |
2439 | */ | |
221dee28 | 2440 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2441 | { |
2442 | unsigned long flags; | |
2443 | int ret; | |
2444 | ||
a7b422cd KRW |
2445 | if (cpufreq_disabled()) |
2446 | return -ENODEV; | |
2447 | ||
1da177e4 | 2448 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2449 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2450 | driver_data->target) || |
2451 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2452 | driver_data->target)) || |
2453 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2454 | return -EINVAL; |
2455 | ||
2d06d8c4 | 2456 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2457 | |
fdd320da RW |
2458 | /* Protect against concurrent CPU online/offline. */ |
2459 | get_online_cpus(); | |
2460 | ||
0d1857a1 | 2461 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2462 | if (cpufreq_driver) { |
0d1857a1 | 2463 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2464 | ret = -EEXIST; |
2465 | goto out; | |
1da177e4 | 2466 | } |
1c3d85dd | 2467 | cpufreq_driver = driver_data; |
0d1857a1 | 2468 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2469 | |
bc68b7df VK |
2470 | if (driver_data->setpolicy) |
2471 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2472 | ||
7a6c79f2 RW |
2473 | if (cpufreq_boost_supported()) { |
2474 | ret = create_boost_sysfs_file(); | |
2475 | if (ret) | |
2476 | goto err_null_driver; | |
2477 | } | |
6f19efc0 | 2478 | |
8a25a2fd | 2479 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2480 | if (ret) |
6f19efc0 | 2481 | goto err_boost_unreg; |
1da177e4 | 2482 | |
ce1bcfe9 VK |
2483 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2484 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2485 | /* if all ->init() calls failed, unregister */ |
ce1bcfe9 VK |
2486 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2487 | driver_data->name); | |
2488 | goto err_if_unreg; | |
1da177e4 LT |
2489 | } |
2490 | ||
8f5bc2ab | 2491 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2492 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2493 | |
fdd320da RW |
2494 | out: |
2495 | put_online_cpus(); | |
2496 | return ret; | |
2497 | ||
8a25a2fd KS |
2498 | err_if_unreg: |
2499 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2500 | err_boost_unreg: |
44139ed4 | 2501 | remove_boost_sysfs_file(); |
8f5bc2ab | 2502 | err_null_driver: |
0d1857a1 | 2503 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2504 | cpufreq_driver = NULL; |
0d1857a1 | 2505 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da | 2506 | goto out; |
1da177e4 LT |
2507 | } |
2508 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2509 | ||
1da177e4 LT |
2510 | /** |
2511 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2512 | * | |
bb176f7d | 2513 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2514 | * the right to do so, i.e. if you have succeeded in initialising before! |
2515 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2516 | * currently not initialised. | |
2517 | */ | |
221dee28 | 2518 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2519 | { |
2520 | unsigned long flags; | |
2521 | ||
1c3d85dd | 2522 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2523 | return -EINVAL; |
1da177e4 | 2524 | |
2d06d8c4 | 2525 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2526 | |
454d3a25 SAS |
2527 | /* Protect against concurrent cpu hotplug */ |
2528 | get_online_cpus(); | |
8a25a2fd | 2529 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2530 | remove_boost_sysfs_file(); |
65edc68c | 2531 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2532 | |
0d1857a1 | 2533 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2534 | |
1c3d85dd | 2535 | cpufreq_driver = NULL; |
6eed9404 | 2536 | |
0d1857a1 | 2537 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
454d3a25 | 2538 | put_online_cpus(); |
1da177e4 LT |
2539 | |
2540 | return 0; | |
2541 | } | |
2542 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2543 | |
90de2a4a DA |
2544 | /* |
2545 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2546 | * or mutexes when secondary CPUs are halted. | |
2547 | */ | |
2548 | static struct syscore_ops cpufreq_syscore_ops = { | |
2549 | .shutdown = cpufreq_suspend, | |
2550 | }; | |
2551 | ||
c82bd444 VK |
2552 | struct kobject *cpufreq_global_kobject; |
2553 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2554 | ||
5a01f2e8 VP |
2555 | static int __init cpufreq_core_init(void) |
2556 | { | |
a7b422cd KRW |
2557 | if (cpufreq_disabled()) |
2558 | return -ENODEV; | |
2559 | ||
8eec1020 | 2560 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2561 | BUG_ON(!cpufreq_global_kobject); |
2562 | ||
90de2a4a DA |
2563 | register_syscore_ops(&cpufreq_syscore_ops); |
2564 | ||
5a01f2e8 VP |
2565 | return 0; |
2566 | } | |
5a01f2e8 | 2567 | core_initcall(cpufreq_core_init); |