Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
2f0aea93 | 29 | #include <linux/suspend.h> |
5ff0a268 | 30 | #include <linux/tick.h> |
6f4f2723 TR |
31 | #include <trace/events/power.h> |
32 | ||
1da177e4 | 33 | /** |
cd878479 | 34 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
35 | * level driver of CPUFreq support, and its spinlock. This lock |
36 | * also protects the cpufreq_cpu_data array. | |
37 | */ | |
1c3d85dd | 38 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 39 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
8414809c | 40 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback); |
bb176f7d | 41 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
6f1e4efd | 42 | DEFINE_MUTEX(cpufreq_governor_lock); |
c88a1f8b | 43 | static LIST_HEAD(cpufreq_policy_list); |
bb176f7d | 44 | |
084f3493 | 45 | /* This one keeps track of the previously set governor of a removed CPU */ |
e77b89f1 | 46 | static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor); |
1da177e4 | 47 | |
2f0aea93 VK |
48 | /* Flag to suspend/resume CPUFreq governors */ |
49 | static bool cpufreq_suspended; | |
50 | ||
9c0ebcf7 VK |
51 | static inline bool has_target(void) |
52 | { | |
53 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
54 | } | |
55 | ||
6eed9404 VK |
56 | /* |
57 | * rwsem to guarantee that cpufreq driver module doesn't unload during critical | |
58 | * sections | |
59 | */ | |
60 | static DECLARE_RWSEM(cpufreq_rwsem); | |
61 | ||
1da177e4 | 62 | /* internal prototypes */ |
29464f28 DJ |
63 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
64 | unsigned int event); | |
5a01f2e8 | 65 | static unsigned int __cpufreq_get(unsigned int cpu); |
65f27f38 | 66 | static void handle_update(struct work_struct *work); |
1da177e4 LT |
67 | |
68 | /** | |
32ee8c3e DJ |
69 | * Two notifier lists: the "policy" list is involved in the |
70 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
71 | * "transition" list for kernel code that needs to handle |
72 | * changes to devices when the CPU clock speed changes. | |
73 | * The mutex locks both lists. | |
74 | */ | |
e041c683 | 75 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 76 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 77 | |
74212ca4 | 78 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
79 | static int __init init_cpufreq_transition_notifier_list(void) |
80 | { | |
81 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 82 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
83 | return 0; |
84 | } | |
b3438f82 | 85 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 86 | |
a7b422cd | 87 | static int off __read_mostly; |
da584455 | 88 | static int cpufreq_disabled(void) |
a7b422cd KRW |
89 | { |
90 | return off; | |
91 | } | |
92 | void disable_cpufreq(void) | |
93 | { | |
94 | off = 1; | |
95 | } | |
1da177e4 | 96 | static LIST_HEAD(cpufreq_governor_list); |
29464f28 | 97 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 98 | |
4d5dcc42 VK |
99 | bool have_governor_per_policy(void) |
100 | { | |
0b981e70 | 101 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 102 | } |
3f869d6d | 103 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 104 | |
944e9a03 VK |
105 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
106 | { | |
107 | if (have_governor_per_policy()) | |
108 | return &policy->kobj; | |
109 | else | |
110 | return cpufreq_global_kobject; | |
111 | } | |
112 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
113 | ||
72a4ce34 VK |
114 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
115 | { | |
116 | u64 idle_time; | |
117 | u64 cur_wall_time; | |
118 | u64 busy_time; | |
119 | ||
120 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
121 | ||
122 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
123 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
124 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
125 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
126 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
127 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
128 | ||
129 | idle_time = cur_wall_time - busy_time; | |
130 | if (wall) | |
131 | *wall = cputime_to_usecs(cur_wall_time); | |
132 | ||
133 | return cputime_to_usecs(idle_time); | |
134 | } | |
135 | ||
136 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
137 | { | |
138 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
139 | ||
140 | if (idle_time == -1ULL) | |
141 | return get_cpu_idle_time_jiffy(cpu, wall); | |
142 | else if (!io_busy) | |
143 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
144 | ||
145 | return idle_time; | |
146 | } | |
147 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
148 | ||
70e9e778 VK |
149 | /* |
150 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
151 | * drivers of SMP systems. It will do following: | |
152 | * - validate & show freq table passed | |
153 | * - set policies transition latency | |
154 | * - policy->cpus with all possible CPUs | |
155 | */ | |
156 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
157 | struct cpufreq_frequency_table *table, | |
158 | unsigned int transition_latency) | |
159 | { | |
160 | int ret; | |
161 | ||
162 | ret = cpufreq_table_validate_and_show(policy, table); | |
163 | if (ret) { | |
164 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
165 | return ret; | |
166 | } | |
167 | ||
168 | policy->cpuinfo.transition_latency = transition_latency; | |
169 | ||
170 | /* | |
171 | * The driver only supports the SMP configuartion where all processors | |
172 | * share the clock and voltage and clock. | |
173 | */ | |
174 | cpumask_setall(policy->cpus); | |
175 | ||
176 | return 0; | |
177 | } | |
178 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
179 | ||
652ed95d VK |
180 | unsigned int cpufreq_generic_get(unsigned int cpu) |
181 | { | |
182 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
183 | ||
184 | if (!policy || IS_ERR(policy->clk)) { | |
e837f9b5 JP |
185 | pr_err("%s: No %s associated to cpu: %d\n", |
186 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
187 | return 0; |
188 | } | |
189 | ||
190 | return clk_get_rate(policy->clk) / 1000; | |
191 | } | |
192 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
193 | ||
e0b3165b VK |
194 | /* Only for cpufreq core internal use */ |
195 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) | |
196 | { | |
197 | return per_cpu(cpufreq_cpu_data, cpu); | |
198 | } | |
199 | ||
6eed9404 | 200 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 201 | { |
6eed9404 | 202 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
203 | unsigned long flags; |
204 | ||
6eed9404 VK |
205 | if (cpufreq_disabled() || (cpu >= nr_cpu_ids)) |
206 | return NULL; | |
207 | ||
208 | if (!down_read_trylock(&cpufreq_rwsem)) | |
209 | return NULL; | |
1da177e4 LT |
210 | |
211 | /* get the cpufreq driver */ | |
1c3d85dd | 212 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 213 | |
6eed9404 VK |
214 | if (cpufreq_driver) { |
215 | /* get the CPU */ | |
216 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
217 | if (policy) | |
218 | kobject_get(&policy->kobj); | |
219 | } | |
1da177e4 | 220 | |
6eed9404 | 221 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 222 | |
3a3e9e06 | 223 | if (!policy) |
6eed9404 | 224 | up_read(&cpufreq_rwsem); |
1da177e4 | 225 | |
3a3e9e06 | 226 | return policy; |
a9144436 | 227 | } |
1da177e4 LT |
228 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
229 | ||
3a3e9e06 | 230 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 231 | { |
d5aaffa9 DB |
232 | if (cpufreq_disabled()) |
233 | return; | |
234 | ||
6eed9404 VK |
235 | kobject_put(&policy->kobj); |
236 | up_read(&cpufreq_rwsem); | |
1da177e4 LT |
237 | } |
238 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
239 | ||
1da177e4 LT |
240 | /********************************************************************* |
241 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
242 | *********************************************************************/ | |
243 | ||
244 | /** | |
245 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
246 | * | |
247 | * This function alters the system "loops_per_jiffy" for the clock | |
248 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 249 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
250 | * per-CPU loops_per_jiffy value wherever possible. |
251 | */ | |
252 | #ifndef CONFIG_SMP | |
253 | static unsigned long l_p_j_ref; | |
bb176f7d | 254 | static unsigned int l_p_j_ref_freq; |
1da177e4 | 255 | |
858119e1 | 256 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 LT |
257 | { |
258 | if (ci->flags & CPUFREQ_CONST_LOOPS) | |
259 | return; | |
260 | ||
261 | if (!l_p_j_ref_freq) { | |
262 | l_p_j_ref = loops_per_jiffy; | |
263 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
264 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
265 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 266 | } |
bb176f7d | 267 | if ((val == CPUFREQ_POSTCHANGE && ci->old != ci->new) || |
42d4dc3f | 268 | (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) { |
e08f5f5b GS |
269 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
270 | ci->new); | |
e837f9b5 JP |
271 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
272 | loops_per_jiffy, ci->new); | |
1da177e4 LT |
273 | } |
274 | } | |
275 | #else | |
e08f5f5b GS |
276 | static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
277 | { | |
278 | return; | |
279 | } | |
1da177e4 LT |
280 | #endif |
281 | ||
0956df9c | 282 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 283 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
284 | { |
285 | BUG_ON(irqs_disabled()); | |
286 | ||
d5aaffa9 DB |
287 | if (cpufreq_disabled()) |
288 | return; | |
289 | ||
1c3d85dd | 290 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 291 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 292 | state, freqs->new); |
1da177e4 | 293 | |
1da177e4 | 294 | switch (state) { |
e4472cb3 | 295 | |
1da177e4 | 296 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 297 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
298 | * which is not equal to what the cpufreq core thinks is |
299 | * "old frequency". | |
1da177e4 | 300 | */ |
1c3d85dd | 301 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
302 | if ((policy) && (policy->cpu == freqs->cpu) && |
303 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
304 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
305 | freqs->old, policy->cur); | |
e4472cb3 | 306 | freqs->old = policy->cur; |
1da177e4 LT |
307 | } |
308 | } | |
b4dfdbb3 | 309 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 310 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
311 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
312 | break; | |
e4472cb3 | 313 | |
1da177e4 LT |
314 | case CPUFREQ_POSTCHANGE: |
315 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
316 | pr_debug("FREQ: %lu - CPU: %lu\n", |
317 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 318 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 319 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 320 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
321 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
322 | policy->cur = freqs->new; | |
1da177e4 LT |
323 | break; |
324 | } | |
1da177e4 | 325 | } |
bb176f7d | 326 | |
b43a7ffb VK |
327 | /** |
328 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
329 | * on frequency transition. | |
330 | * | |
331 | * This function calls the transition notifiers and the "adjust_jiffies" | |
332 | * function. It is called twice on all CPU frequency changes that have | |
333 | * external effects. | |
334 | */ | |
335 | void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
336 | struct cpufreq_freqs *freqs, unsigned int state) | |
337 | { | |
338 | for_each_cpu(freqs->cpu, policy->cpus) | |
339 | __cpufreq_notify_transition(policy, freqs, state); | |
340 | } | |
1da177e4 LT |
341 | EXPORT_SYMBOL_GPL(cpufreq_notify_transition); |
342 | ||
f7ba3b41 VK |
343 | /* Do post notifications when there are chances that transition has failed */ |
344 | void cpufreq_notify_post_transition(struct cpufreq_policy *policy, | |
345 | struct cpufreq_freqs *freqs, int transition_failed) | |
346 | { | |
347 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
348 | if (!transition_failed) | |
349 | return; | |
350 | ||
351 | swap(freqs->old, freqs->new); | |
352 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
353 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
354 | } | |
355 | EXPORT_SYMBOL_GPL(cpufreq_notify_post_transition); | |
356 | ||
1da177e4 | 357 | |
1da177e4 LT |
358 | /********************************************************************* |
359 | * SYSFS INTERFACE * | |
360 | *********************************************************************/ | |
8a5c74a1 | 361 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
362 | struct attribute *attr, char *buf) |
363 | { | |
364 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
365 | } | |
366 | ||
367 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
368 | const char *buf, size_t count) | |
369 | { | |
370 | int ret, enable; | |
371 | ||
372 | ret = sscanf(buf, "%d", &enable); | |
373 | if (ret != 1 || enable < 0 || enable > 1) | |
374 | return -EINVAL; | |
375 | ||
376 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
377 | pr_err("%s: Cannot %s BOOST!\n", |
378 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
379 | return -EINVAL; |
380 | } | |
381 | ||
e837f9b5 JP |
382 | pr_debug("%s: cpufreq BOOST %s\n", |
383 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
384 | |
385 | return count; | |
386 | } | |
387 | define_one_global_rw(boost); | |
1da177e4 | 388 | |
3bcb09a3 JF |
389 | static struct cpufreq_governor *__find_governor(const char *str_governor) |
390 | { | |
391 | struct cpufreq_governor *t; | |
392 | ||
393 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) | |
29464f28 | 394 | if (!strnicmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
395 | return t; |
396 | ||
397 | return NULL; | |
398 | } | |
399 | ||
1da177e4 LT |
400 | /** |
401 | * cpufreq_parse_governor - parse a governor string | |
402 | */ | |
905d77cd | 403 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
404 | struct cpufreq_governor **governor) |
405 | { | |
3bcb09a3 | 406 | int err = -EINVAL; |
1c3d85dd RW |
407 | |
408 | if (!cpufreq_driver) | |
3bcb09a3 JF |
409 | goto out; |
410 | ||
1c3d85dd | 411 | if (cpufreq_driver->setpolicy) { |
1da177e4 LT |
412 | if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
413 | *policy = CPUFREQ_POLICY_PERFORMANCE; | |
3bcb09a3 | 414 | err = 0; |
e08f5f5b GS |
415 | } else if (!strnicmp(str_governor, "powersave", |
416 | CPUFREQ_NAME_LEN)) { | |
1da177e4 | 417 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 418 | err = 0; |
1da177e4 | 419 | } |
9c0ebcf7 | 420 | } else if (has_target()) { |
1da177e4 | 421 | struct cpufreq_governor *t; |
3bcb09a3 | 422 | |
3fc54d37 | 423 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 JF |
424 | |
425 | t = __find_governor(str_governor); | |
426 | ||
ea714970 | 427 | if (t == NULL) { |
1a8e1463 | 428 | int ret; |
ea714970 | 429 | |
1a8e1463 KC |
430 | mutex_unlock(&cpufreq_governor_mutex); |
431 | ret = request_module("cpufreq_%s", str_governor); | |
432 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 433 | |
1a8e1463 KC |
434 | if (ret == 0) |
435 | t = __find_governor(str_governor); | |
ea714970 JF |
436 | } |
437 | ||
3bcb09a3 JF |
438 | if (t != NULL) { |
439 | *governor = t; | |
440 | err = 0; | |
1da177e4 | 441 | } |
3bcb09a3 | 442 | |
3fc54d37 | 443 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 444 | } |
29464f28 | 445 | out: |
3bcb09a3 | 446 | return err; |
1da177e4 | 447 | } |
1da177e4 | 448 | |
1da177e4 | 449 | /** |
e08f5f5b GS |
450 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
451 | * print out cpufreq information | |
1da177e4 LT |
452 | * |
453 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
454 | * "unsigned int". | |
455 | */ | |
456 | ||
32ee8c3e DJ |
457 | #define show_one(file_name, object) \ |
458 | static ssize_t show_##file_name \ | |
905d77cd | 459 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 460 | { \ |
29464f28 | 461 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
462 | } |
463 | ||
464 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
465 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 466 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
467 | show_one(scaling_min_freq, min); |
468 | show_one(scaling_max_freq, max); | |
469 | show_one(scaling_cur_freq, cur); | |
470 | ||
037ce839 | 471 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 472 | struct cpufreq_policy *new_policy); |
7970e08b | 473 | |
1da177e4 LT |
474 | /** |
475 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
476 | */ | |
477 | #define store_one(file_name, object) \ | |
478 | static ssize_t store_##file_name \ | |
905d77cd | 479 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 480 | { \ |
5136fa56 | 481 | int ret; \ |
1da177e4 LT |
482 | struct cpufreq_policy new_policy; \ |
483 | \ | |
484 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ | |
485 | if (ret) \ | |
486 | return -EINVAL; \ | |
487 | \ | |
29464f28 | 488 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
489 | if (ret != 1) \ |
490 | return -EINVAL; \ | |
491 | \ | |
037ce839 | 492 | ret = cpufreq_set_policy(policy, &new_policy); \ |
7970e08b | 493 | policy->user_policy.object = policy->object; \ |
1da177e4 LT |
494 | \ |
495 | return ret ? ret : count; \ | |
496 | } | |
497 | ||
29464f28 DJ |
498 | store_one(scaling_min_freq, min); |
499 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
500 | |
501 | /** | |
502 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
503 | */ | |
905d77cd DJ |
504 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
505 | char *buf) | |
1da177e4 | 506 | { |
5a01f2e8 | 507 | unsigned int cur_freq = __cpufreq_get(policy->cpu); |
1da177e4 LT |
508 | if (!cur_freq) |
509 | return sprintf(buf, "<unknown>"); | |
510 | return sprintf(buf, "%u\n", cur_freq); | |
511 | } | |
512 | ||
1da177e4 LT |
513 | /** |
514 | * show_scaling_governor - show the current policy for the specified CPU | |
515 | */ | |
905d77cd | 516 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 517 | { |
29464f28 | 518 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
519 | return sprintf(buf, "powersave\n"); |
520 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
521 | return sprintf(buf, "performance\n"); | |
522 | else if (policy->governor) | |
4b972f0b | 523 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 524 | policy->governor->name); |
1da177e4 LT |
525 | return -EINVAL; |
526 | } | |
527 | ||
1da177e4 LT |
528 | /** |
529 | * store_scaling_governor - store policy for the specified CPU | |
530 | */ | |
905d77cd DJ |
531 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
532 | const char *buf, size_t count) | |
1da177e4 | 533 | { |
5136fa56 | 534 | int ret; |
1da177e4 LT |
535 | char str_governor[16]; |
536 | struct cpufreq_policy new_policy; | |
537 | ||
538 | ret = cpufreq_get_policy(&new_policy, policy->cpu); | |
539 | if (ret) | |
540 | return ret; | |
541 | ||
29464f28 | 542 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
543 | if (ret != 1) |
544 | return -EINVAL; | |
545 | ||
e08f5f5b GS |
546 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
547 | &new_policy.governor)) | |
1da177e4 LT |
548 | return -EINVAL; |
549 | ||
037ce839 | 550 | ret = cpufreq_set_policy(policy, &new_policy); |
7970e08b TR |
551 | |
552 | policy->user_policy.policy = policy->policy; | |
553 | policy->user_policy.governor = policy->governor; | |
7970e08b | 554 | |
e08f5f5b GS |
555 | if (ret) |
556 | return ret; | |
557 | else | |
558 | return count; | |
1da177e4 LT |
559 | } |
560 | ||
561 | /** | |
562 | * show_scaling_driver - show the cpufreq driver currently loaded | |
563 | */ | |
905d77cd | 564 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 565 | { |
1c3d85dd | 566 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
567 | } |
568 | ||
569 | /** | |
570 | * show_scaling_available_governors - show the available CPUfreq governors | |
571 | */ | |
905d77cd DJ |
572 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
573 | char *buf) | |
1da177e4 LT |
574 | { |
575 | ssize_t i = 0; | |
576 | struct cpufreq_governor *t; | |
577 | ||
9c0ebcf7 | 578 | if (!has_target()) { |
1da177e4 LT |
579 | i += sprintf(buf, "performance powersave"); |
580 | goto out; | |
581 | } | |
582 | ||
583 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { | |
29464f28 DJ |
584 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
585 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 586 | goto out; |
4b972f0b | 587 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 588 | } |
7d5e350f | 589 | out: |
1da177e4 LT |
590 | i += sprintf(&buf[i], "\n"); |
591 | return i; | |
592 | } | |
e8628dd0 | 593 | |
f4fd3797 | 594 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
595 | { |
596 | ssize_t i = 0; | |
597 | unsigned int cpu; | |
598 | ||
835481d9 | 599 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
600 | if (i) |
601 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
602 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
603 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 604 | break; |
1da177e4 LT |
605 | } |
606 | i += sprintf(&buf[i], "\n"); | |
607 | return i; | |
608 | } | |
f4fd3797 | 609 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 610 | |
e8628dd0 DW |
611 | /** |
612 | * show_related_cpus - show the CPUs affected by each transition even if | |
613 | * hw coordination is in use | |
614 | */ | |
615 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
616 | { | |
f4fd3797 | 617 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
618 | } |
619 | ||
620 | /** | |
621 | * show_affected_cpus - show the CPUs affected by each transition | |
622 | */ | |
623 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
624 | { | |
f4fd3797 | 625 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
626 | } |
627 | ||
9e76988e | 628 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 629 | const char *buf, size_t count) |
9e76988e VP |
630 | { |
631 | unsigned int freq = 0; | |
632 | unsigned int ret; | |
633 | ||
879000f9 | 634 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
635 | return -EINVAL; |
636 | ||
637 | ret = sscanf(buf, "%u", &freq); | |
638 | if (ret != 1) | |
639 | return -EINVAL; | |
640 | ||
641 | policy->governor->store_setspeed(policy, freq); | |
642 | ||
643 | return count; | |
644 | } | |
645 | ||
646 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
647 | { | |
879000f9 | 648 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
649 | return sprintf(buf, "<unsupported>\n"); |
650 | ||
651 | return policy->governor->show_setspeed(policy, buf); | |
652 | } | |
1da177e4 | 653 | |
e2f74f35 | 654 | /** |
8bf1ac72 | 655 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
656 | */ |
657 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
658 | { | |
659 | unsigned int limit; | |
660 | int ret; | |
1c3d85dd RW |
661 | if (cpufreq_driver->bios_limit) { |
662 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
663 | if (!ret) |
664 | return sprintf(buf, "%u\n", limit); | |
665 | } | |
666 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
667 | } | |
668 | ||
6dad2a29 BP |
669 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
670 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
671 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
672 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
673 | cpufreq_freq_attr_ro(scaling_available_governors); | |
674 | cpufreq_freq_attr_ro(scaling_driver); | |
675 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
676 | cpufreq_freq_attr_ro(bios_limit); | |
677 | cpufreq_freq_attr_ro(related_cpus); | |
678 | cpufreq_freq_attr_ro(affected_cpus); | |
679 | cpufreq_freq_attr_rw(scaling_min_freq); | |
680 | cpufreq_freq_attr_rw(scaling_max_freq); | |
681 | cpufreq_freq_attr_rw(scaling_governor); | |
682 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 683 | |
905d77cd | 684 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
685 | &cpuinfo_min_freq.attr, |
686 | &cpuinfo_max_freq.attr, | |
ed129784 | 687 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
688 | &scaling_min_freq.attr, |
689 | &scaling_max_freq.attr, | |
690 | &affected_cpus.attr, | |
e8628dd0 | 691 | &related_cpus.attr, |
1da177e4 LT |
692 | &scaling_governor.attr, |
693 | &scaling_driver.attr, | |
694 | &scaling_available_governors.attr, | |
9e76988e | 695 | &scaling_setspeed.attr, |
1da177e4 LT |
696 | NULL |
697 | }; | |
698 | ||
29464f28 DJ |
699 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
700 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 701 | |
29464f28 | 702 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 703 | { |
905d77cd DJ |
704 | struct cpufreq_policy *policy = to_policy(kobj); |
705 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 706 | ssize_t ret; |
6eed9404 VK |
707 | |
708 | if (!down_read_trylock(&cpufreq_rwsem)) | |
1b750e3b | 709 | return -EINVAL; |
5a01f2e8 | 710 | |
ad7722da | 711 | down_read(&policy->rwsem); |
5a01f2e8 | 712 | |
e08f5f5b GS |
713 | if (fattr->show) |
714 | ret = fattr->show(policy, buf); | |
715 | else | |
716 | ret = -EIO; | |
717 | ||
ad7722da | 718 | up_read(&policy->rwsem); |
6eed9404 | 719 | up_read(&cpufreq_rwsem); |
1b750e3b | 720 | |
1da177e4 LT |
721 | return ret; |
722 | } | |
723 | ||
905d77cd DJ |
724 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
725 | const char *buf, size_t count) | |
1da177e4 | 726 | { |
905d77cd DJ |
727 | struct cpufreq_policy *policy = to_policy(kobj); |
728 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 729 | ssize_t ret = -EINVAL; |
6eed9404 | 730 | |
4f750c93 SB |
731 | get_online_cpus(); |
732 | ||
733 | if (!cpu_online(policy->cpu)) | |
734 | goto unlock; | |
735 | ||
6eed9404 | 736 | if (!down_read_trylock(&cpufreq_rwsem)) |
4f750c93 | 737 | goto unlock; |
5a01f2e8 | 738 | |
ad7722da | 739 | down_write(&policy->rwsem); |
5a01f2e8 | 740 | |
e08f5f5b GS |
741 | if (fattr->store) |
742 | ret = fattr->store(policy, buf, count); | |
743 | else | |
744 | ret = -EIO; | |
745 | ||
ad7722da | 746 | up_write(&policy->rwsem); |
6eed9404 | 747 | |
6eed9404 | 748 | up_read(&cpufreq_rwsem); |
4f750c93 SB |
749 | unlock: |
750 | put_online_cpus(); | |
751 | ||
1da177e4 LT |
752 | return ret; |
753 | } | |
754 | ||
905d77cd | 755 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 756 | { |
905d77cd | 757 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 758 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
759 | complete(&policy->kobj_unregister); |
760 | } | |
761 | ||
52cf25d0 | 762 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
763 | .show = show, |
764 | .store = store, | |
765 | }; | |
766 | ||
767 | static struct kobj_type ktype_cpufreq = { | |
768 | .sysfs_ops = &sysfs_ops, | |
769 | .default_attrs = default_attrs, | |
770 | .release = cpufreq_sysfs_release, | |
771 | }; | |
772 | ||
2361be23 VK |
773 | struct kobject *cpufreq_global_kobject; |
774 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
775 | ||
776 | static int cpufreq_global_kobject_usage; | |
777 | ||
778 | int cpufreq_get_global_kobject(void) | |
779 | { | |
780 | if (!cpufreq_global_kobject_usage++) | |
781 | return kobject_add(cpufreq_global_kobject, | |
782 | &cpu_subsys.dev_root->kobj, "%s", "cpufreq"); | |
783 | ||
784 | return 0; | |
785 | } | |
786 | EXPORT_SYMBOL(cpufreq_get_global_kobject); | |
787 | ||
788 | void cpufreq_put_global_kobject(void) | |
789 | { | |
790 | if (!--cpufreq_global_kobject_usage) | |
791 | kobject_del(cpufreq_global_kobject); | |
792 | } | |
793 | EXPORT_SYMBOL(cpufreq_put_global_kobject); | |
794 | ||
795 | int cpufreq_sysfs_create_file(const struct attribute *attr) | |
796 | { | |
797 | int ret = cpufreq_get_global_kobject(); | |
798 | ||
799 | if (!ret) { | |
800 | ret = sysfs_create_file(cpufreq_global_kobject, attr); | |
801 | if (ret) | |
802 | cpufreq_put_global_kobject(); | |
803 | } | |
804 | ||
805 | return ret; | |
806 | } | |
807 | EXPORT_SYMBOL(cpufreq_sysfs_create_file); | |
808 | ||
809 | void cpufreq_sysfs_remove_file(const struct attribute *attr) | |
810 | { | |
811 | sysfs_remove_file(cpufreq_global_kobject, attr); | |
812 | cpufreq_put_global_kobject(); | |
813 | } | |
814 | EXPORT_SYMBOL(cpufreq_sysfs_remove_file); | |
815 | ||
19d6f7ec | 816 | /* symlink affected CPUs */ |
308b60e7 | 817 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
818 | { |
819 | unsigned int j; | |
820 | int ret = 0; | |
821 | ||
822 | for_each_cpu(j, policy->cpus) { | |
8a25a2fd | 823 | struct device *cpu_dev; |
19d6f7ec | 824 | |
308b60e7 | 825 | if (j == policy->cpu) |
19d6f7ec | 826 | continue; |
19d6f7ec | 827 | |
e8fdde10 | 828 | pr_debug("Adding link for CPU: %u\n", j); |
8a25a2fd KS |
829 | cpu_dev = get_cpu_device(j); |
830 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
19d6f7ec | 831 | "cpufreq"); |
71c3461e RW |
832 | if (ret) |
833 | break; | |
19d6f7ec DJ |
834 | } |
835 | return ret; | |
836 | } | |
837 | ||
308b60e7 | 838 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy, |
8a25a2fd | 839 | struct device *dev) |
909a694e DJ |
840 | { |
841 | struct freq_attr **drv_attr; | |
909a694e | 842 | int ret = 0; |
909a694e DJ |
843 | |
844 | /* prepare interface data */ | |
845 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, | |
8a25a2fd | 846 | &dev->kobj, "cpufreq"); |
909a694e DJ |
847 | if (ret) |
848 | return ret; | |
849 | ||
850 | /* set up files for this cpu device */ | |
1c3d85dd | 851 | drv_attr = cpufreq_driver->attr; |
909a694e DJ |
852 | while ((drv_attr) && (*drv_attr)) { |
853 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); | |
854 | if (ret) | |
1c3d85dd | 855 | goto err_out_kobj_put; |
909a694e DJ |
856 | drv_attr++; |
857 | } | |
1c3d85dd | 858 | if (cpufreq_driver->get) { |
909a694e DJ |
859 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
860 | if (ret) | |
1c3d85dd | 861 | goto err_out_kobj_put; |
909a694e | 862 | } |
9c0ebcf7 | 863 | if (has_target()) { |
909a694e DJ |
864 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); |
865 | if (ret) | |
1c3d85dd | 866 | goto err_out_kobj_put; |
909a694e | 867 | } |
1c3d85dd | 868 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
869 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
870 | if (ret) | |
1c3d85dd | 871 | goto err_out_kobj_put; |
e2f74f35 | 872 | } |
909a694e | 873 | |
308b60e7 | 874 | ret = cpufreq_add_dev_symlink(policy); |
ecf7e461 DJ |
875 | if (ret) |
876 | goto err_out_kobj_put; | |
877 | ||
e18f1682 SB |
878 | return ret; |
879 | ||
880 | err_out_kobj_put: | |
881 | kobject_put(&policy->kobj); | |
882 | wait_for_completion(&policy->kobj_unregister); | |
883 | return ret; | |
884 | } | |
885 | ||
886 | static void cpufreq_init_policy(struct cpufreq_policy *policy) | |
887 | { | |
6e2c89d1 | 888 | struct cpufreq_governor *gov = NULL; |
e18f1682 SB |
889 | struct cpufreq_policy new_policy; |
890 | int ret = 0; | |
891 | ||
d5b73cd8 | 892 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 893 | |
6e2c89d1 | 894 | /* Update governor of new_policy to the governor used before hotplug */ |
895 | gov = __find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu)); | |
896 | if (gov) | |
897 | pr_debug("Restoring governor %s for cpu %d\n", | |
898 | policy->governor->name, policy->cpu); | |
899 | else | |
900 | gov = CPUFREQ_DEFAULT_GOVERNOR; | |
901 | ||
902 | new_policy.governor = gov; | |
903 | ||
a27a9ab7 JB |
904 | /* Use the default policy if its valid. */ |
905 | if (cpufreq_driver->setpolicy) | |
6e2c89d1 | 906 | cpufreq_parse_governor(gov->name, &new_policy.policy, NULL); |
ecf7e461 DJ |
907 | |
908 | /* set default policy */ | |
037ce839 | 909 | ret = cpufreq_set_policy(policy, &new_policy); |
ecf7e461 | 910 | if (ret) { |
2d06d8c4 | 911 | pr_debug("setting policy failed\n"); |
1c3d85dd RW |
912 | if (cpufreq_driver->exit) |
913 | cpufreq_driver->exit(policy); | |
ecf7e461 | 914 | } |
909a694e DJ |
915 | } |
916 | ||
fcf80582 | 917 | #ifdef CONFIG_HOTPLUG_CPU |
d8d3b471 | 918 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, |
42f921a6 | 919 | unsigned int cpu, struct device *dev) |
fcf80582 | 920 | { |
9c0ebcf7 | 921 | int ret = 0; |
fcf80582 VK |
922 | unsigned long flags; |
923 | ||
9c0ebcf7 | 924 | if (has_target()) { |
3de9bdeb VK |
925 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
926 | if (ret) { | |
927 | pr_err("%s: Failed to stop governor\n", __func__); | |
928 | return ret; | |
929 | } | |
930 | } | |
fcf80582 | 931 | |
ad7722da | 932 | down_write(&policy->rwsem); |
2eaa3e2d | 933 | |
0d1857a1 | 934 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 935 | |
fcf80582 VK |
936 | cpumask_set_cpu(cpu, policy->cpus); |
937 | per_cpu(cpufreq_cpu_data, cpu) = policy; | |
0d1857a1 | 938 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fcf80582 | 939 | |
ad7722da | 940 | up_write(&policy->rwsem); |
2eaa3e2d | 941 | |
9c0ebcf7 | 942 | if (has_target()) { |
3de9bdeb VK |
943 | if ((ret = __cpufreq_governor(policy, CPUFREQ_GOV_START)) || |
944 | (ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS))) { | |
945 | pr_err("%s: Failed to start governor\n", __func__); | |
946 | return ret; | |
947 | } | |
820c6ca2 | 948 | } |
fcf80582 | 949 | |
42f921a6 | 950 | return sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); |
fcf80582 VK |
951 | } |
952 | #endif | |
1da177e4 | 953 | |
8414809c SB |
954 | static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu) |
955 | { | |
956 | struct cpufreq_policy *policy; | |
957 | unsigned long flags; | |
958 | ||
44871c9c | 959 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
8414809c SB |
960 | |
961 | policy = per_cpu(cpufreq_cpu_data_fallback, cpu); | |
962 | ||
44871c9c | 963 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
8414809c | 964 | |
6e2c89d1 | 965 | policy->governor = NULL; |
966 | ||
8414809c SB |
967 | return policy; |
968 | } | |
969 | ||
e9698cc5 SB |
970 | static struct cpufreq_policy *cpufreq_policy_alloc(void) |
971 | { | |
972 | struct cpufreq_policy *policy; | |
973 | ||
974 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); | |
975 | if (!policy) | |
976 | return NULL; | |
977 | ||
978 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
979 | goto err_free_policy; | |
980 | ||
981 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
982 | goto err_free_cpumask; | |
983 | ||
c88a1f8b | 984 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 985 | init_rwsem(&policy->rwsem); |
986 | ||
e9698cc5 SB |
987 | return policy; |
988 | ||
989 | err_free_cpumask: | |
990 | free_cpumask_var(policy->cpus); | |
991 | err_free_policy: | |
992 | kfree(policy); | |
993 | ||
994 | return NULL; | |
995 | } | |
996 | ||
42f921a6 VK |
997 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) |
998 | { | |
999 | struct kobject *kobj; | |
1000 | struct completion *cmp; | |
1001 | ||
fcd7af91 VK |
1002 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1003 | CPUFREQ_REMOVE_POLICY, policy); | |
1004 | ||
42f921a6 VK |
1005 | down_read(&policy->rwsem); |
1006 | kobj = &policy->kobj; | |
1007 | cmp = &policy->kobj_unregister; | |
1008 | up_read(&policy->rwsem); | |
1009 | kobject_put(kobj); | |
1010 | ||
1011 | /* | |
1012 | * We need to make sure that the underlying kobj is | |
1013 | * actually not referenced anymore by anybody before we | |
1014 | * proceed with unloading. | |
1015 | */ | |
1016 | pr_debug("waiting for dropping of refcount\n"); | |
1017 | wait_for_completion(cmp); | |
1018 | pr_debug("wait complete\n"); | |
1019 | } | |
1020 | ||
e9698cc5 SB |
1021 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
1022 | { | |
1023 | free_cpumask_var(policy->related_cpus); | |
1024 | free_cpumask_var(policy->cpus); | |
1025 | kfree(policy); | |
1026 | } | |
1027 | ||
0d66b91e SB |
1028 | static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
1029 | { | |
99ec899e | 1030 | if (WARN_ON(cpu == policy->cpu)) |
cb38ed5c SB |
1031 | return; |
1032 | ||
ad7722da | 1033 | down_write(&policy->rwsem); |
8efd5765 | 1034 | |
0d66b91e SB |
1035 | policy->last_cpu = policy->cpu; |
1036 | policy->cpu = cpu; | |
1037 | ||
ad7722da | 1038 | up_write(&policy->rwsem); |
8efd5765 | 1039 | |
0d66b91e SB |
1040 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1041 | CPUFREQ_UPDATE_POLICY_CPU, policy); | |
1042 | } | |
1043 | ||
a82fab29 SB |
1044 | static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, |
1045 | bool frozen) | |
1da177e4 | 1046 | { |
fcf80582 | 1047 | unsigned int j, cpu = dev->id; |
65922465 | 1048 | int ret = -ENOMEM; |
1da177e4 | 1049 | struct cpufreq_policy *policy; |
1da177e4 | 1050 | unsigned long flags; |
90e41bac | 1051 | #ifdef CONFIG_HOTPLUG_CPU |
1b274294 | 1052 | struct cpufreq_policy *tpolicy; |
90e41bac | 1053 | #endif |
1da177e4 | 1054 | |
c32b6b8e AR |
1055 | if (cpu_is_offline(cpu)) |
1056 | return 0; | |
1057 | ||
2d06d8c4 | 1058 | pr_debug("adding CPU %u\n", cpu); |
1da177e4 LT |
1059 | |
1060 | #ifdef CONFIG_SMP | |
1061 | /* check whether a different CPU already registered this | |
1062 | * CPU because it is in the same boat. */ | |
1063 | policy = cpufreq_cpu_get(cpu); | |
1064 | if (unlikely(policy)) { | |
8ff69732 | 1065 | cpufreq_cpu_put(policy); |
1da177e4 LT |
1066 | return 0; |
1067 | } | |
5025d628 | 1068 | #endif |
fcf80582 | 1069 | |
6eed9404 VK |
1070 | if (!down_read_trylock(&cpufreq_rwsem)) |
1071 | return 0; | |
1072 | ||
fcf80582 VK |
1073 | #ifdef CONFIG_HOTPLUG_CPU |
1074 | /* Check if this cpu was hot-unplugged earlier and has siblings */ | |
0d1857a1 | 1075 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1b274294 VK |
1076 | list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) { |
1077 | if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) { | |
0d1857a1 | 1078 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
42f921a6 | 1079 | ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev); |
6eed9404 VK |
1080 | up_read(&cpufreq_rwsem); |
1081 | return ret; | |
2eaa3e2d | 1082 | } |
fcf80582 | 1083 | } |
0d1857a1 | 1084 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
1085 | #endif |
1086 | ||
72368d12 RW |
1087 | /* |
1088 | * Restore the saved policy when doing light-weight init and fall back | |
1089 | * to the full init if that fails. | |
1090 | */ | |
1091 | policy = frozen ? cpufreq_policy_restore(cpu) : NULL; | |
1092 | if (!policy) { | |
1093 | frozen = false; | |
8414809c | 1094 | policy = cpufreq_policy_alloc(); |
72368d12 RW |
1095 | if (!policy) |
1096 | goto nomem_out; | |
1097 | } | |
0d66b91e SB |
1098 | |
1099 | /* | |
1100 | * In the resume path, since we restore a saved policy, the assignment | |
1101 | * to policy->cpu is like an update of the existing policy, rather than | |
1102 | * the creation of a brand new one. So we need to perform this update | |
1103 | * by invoking update_policy_cpu(). | |
1104 | */ | |
1105 | if (frozen && cpu != policy->cpu) | |
1106 | update_policy_cpu(policy, cpu); | |
1107 | else | |
1108 | policy->cpu = cpu; | |
1109 | ||
835481d9 | 1110 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1111 | |
1da177e4 | 1112 | init_completion(&policy->kobj_unregister); |
65f27f38 | 1113 | INIT_WORK(&policy->update, handle_update); |
1da177e4 LT |
1114 | |
1115 | /* call driver. From then on the cpufreq must be able | |
1116 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1117 | */ | |
1c3d85dd | 1118 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1119 | if (ret) { |
2d06d8c4 | 1120 | pr_debug("initialization failed\n"); |
2eaa3e2d | 1121 | goto err_set_policy_cpu; |
1da177e4 | 1122 | } |
643ae6e8 | 1123 | |
5a7e56a5 VK |
1124 | /* related cpus should atleast have policy->cpus */ |
1125 | cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); | |
1126 | ||
1127 | /* | |
1128 | * affected cpus must always be the one, which are online. We aren't | |
1129 | * managing offline cpus here. | |
1130 | */ | |
1131 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1132 | ||
1133 | if (!frozen) { | |
1134 | policy->user_policy.min = policy->min; | |
1135 | policy->user_policy.max = policy->max; | |
1136 | } | |
1137 | ||
4e97b631 | 1138 | down_write(&policy->rwsem); |
652ed95d VK |
1139 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1140 | for_each_cpu(j, policy->cpus) | |
1141 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1142 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1143 | ||
da60ce9f VK |
1144 | if (cpufreq_driver->get) { |
1145 | policy->cur = cpufreq_driver->get(policy->cpu); | |
1146 | if (!policy->cur) { | |
1147 | pr_err("%s: ->get() failed\n", __func__); | |
1148 | goto err_get_freq; | |
1149 | } | |
1150 | } | |
1151 | ||
d3916691 VK |
1152 | /* |
1153 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1154 | * frequency table present with cpufreq core. In such cases CPU might be | |
1155 | * unstable if it has to run on that frequency for long duration of time | |
1156 | * and so its better to set it to a frequency which is specified in | |
1157 | * freq-table. This also makes cpufreq stats inconsistent as | |
1158 | * cpufreq-stats would fail to register because current frequency of CPU | |
1159 | * isn't found in freq-table. | |
1160 | * | |
1161 | * Because we don't want this change to effect boot process badly, we go | |
1162 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1163 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1164 | * is initialized to zero). | |
1165 | * | |
1166 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1167 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1168 | * equal to target-freq. | |
1169 | */ | |
1170 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1171 | && has_target()) { | |
1172 | /* Are we running at unknown frequency ? */ | |
1173 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1174 | if (ret == -EINVAL) { | |
1175 | /* Warn user and fix it */ | |
1176 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1177 | __func__, policy->cpu, policy->cur); | |
1178 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1179 | CPUFREQ_RELATION_L); | |
1180 | ||
1181 | /* | |
1182 | * Reaching here after boot in a few seconds may not | |
1183 | * mean that system will remain stable at "unknown" | |
1184 | * frequency for longer duration. Hence, a BUG_ON(). | |
1185 | */ | |
1186 | BUG_ON(ret); | |
1187 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1188 | __func__, policy->cpu, policy->cur); | |
1189 | } | |
1190 | } | |
1191 | ||
a1531acd TR |
1192 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1193 | CPUFREQ_START, policy); | |
1194 | ||
a82fab29 | 1195 | if (!frozen) { |
308b60e7 | 1196 | ret = cpufreq_add_dev_interface(policy, dev); |
a82fab29 SB |
1197 | if (ret) |
1198 | goto err_out_unregister; | |
fcd7af91 VK |
1199 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1200 | CPUFREQ_CREATE_POLICY, policy); | |
a82fab29 | 1201 | } |
8ff69732 | 1202 | |
9515f4d6 VK |
1203 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1204 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1205 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1206 | ||
e18f1682 SB |
1207 | cpufreq_init_policy(policy); |
1208 | ||
08fd8c1c VK |
1209 | if (!frozen) { |
1210 | policy->user_policy.policy = policy->policy; | |
1211 | policy->user_policy.governor = policy->governor; | |
1212 | } | |
4e97b631 | 1213 | up_write(&policy->rwsem); |
08fd8c1c | 1214 | |
038c5b3e | 1215 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
6eed9404 VK |
1216 | up_read(&cpufreq_rwsem); |
1217 | ||
2d06d8c4 | 1218 | pr_debug("initialization complete\n"); |
87c32271 | 1219 | |
1da177e4 LT |
1220 | return 0; |
1221 | ||
1da177e4 | 1222 | err_out_unregister: |
652ed95d | 1223 | err_get_freq: |
0d1857a1 | 1224 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
474deff7 | 1225 | for_each_cpu(j, policy->cpus) |
7a6aedfa | 1226 | per_cpu(cpufreq_cpu_data, j) = NULL; |
0d1857a1 | 1227 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1228 | |
da60ce9f VK |
1229 | if (cpufreq_driver->exit) |
1230 | cpufreq_driver->exit(policy); | |
2eaa3e2d | 1231 | err_set_policy_cpu: |
72368d12 RW |
1232 | if (frozen) { |
1233 | /* Do not leave stale fallback data behind. */ | |
1234 | per_cpu(cpufreq_cpu_data_fallback, cpu) = NULL; | |
42f921a6 | 1235 | cpufreq_policy_put_kobj(policy); |
72368d12 | 1236 | } |
e9698cc5 | 1237 | cpufreq_policy_free(policy); |
42f921a6 | 1238 | |
1da177e4 | 1239 | nomem_out: |
6eed9404 VK |
1240 | up_read(&cpufreq_rwsem); |
1241 | ||
1da177e4 LT |
1242 | return ret; |
1243 | } | |
1244 | ||
a82fab29 SB |
1245 | /** |
1246 | * cpufreq_add_dev - add a CPU device | |
1247 | * | |
1248 | * Adds the cpufreq interface for a CPU device. | |
1249 | * | |
1250 | * The Oracle says: try running cpufreq registration/unregistration concurrently | |
1251 | * with with cpu hotplugging and all hell will break loose. Tried to clean this | |
1252 | * mess up, but more thorough testing is needed. - Mathieu | |
1253 | */ | |
1254 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1255 | { | |
1256 | return __cpufreq_add_dev(dev, sif, false); | |
1257 | } | |
1258 | ||
3a3e9e06 | 1259 | static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, |
42f921a6 | 1260 | unsigned int old_cpu) |
f9ba680d SB |
1261 | { |
1262 | struct device *cpu_dev; | |
f9ba680d SB |
1263 | int ret; |
1264 | ||
1265 | /* first sibling now owns the new sysfs dir */ | |
9c8f1ee4 | 1266 | cpu_dev = get_cpu_device(cpumask_any_but(policy->cpus, old_cpu)); |
a82fab29 | 1267 | |
f9ba680d | 1268 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); |
3a3e9e06 | 1269 | ret = kobject_move(&policy->kobj, &cpu_dev->kobj); |
f9ba680d | 1270 | if (ret) { |
e837f9b5 | 1271 | pr_err("%s: Failed to move kobj: %d\n", __func__, ret); |
f9ba680d | 1272 | |
ad7722da | 1273 | down_write(&policy->rwsem); |
3a3e9e06 | 1274 | cpumask_set_cpu(old_cpu, policy->cpus); |
ad7722da | 1275 | up_write(&policy->rwsem); |
f9ba680d | 1276 | |
3a3e9e06 | 1277 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, |
f9ba680d SB |
1278 | "cpufreq"); |
1279 | ||
1280 | return -EINVAL; | |
1281 | } | |
1282 | ||
1283 | return cpu_dev->id; | |
1284 | } | |
1285 | ||
cedb70af SB |
1286 | static int __cpufreq_remove_dev_prepare(struct device *dev, |
1287 | struct subsys_interface *sif, | |
1288 | bool frozen) | |
1da177e4 | 1289 | { |
f9ba680d | 1290 | unsigned int cpu = dev->id, cpus; |
3de9bdeb | 1291 | int new_cpu, ret; |
1da177e4 | 1292 | unsigned long flags; |
3a3e9e06 | 1293 | struct cpufreq_policy *policy; |
1da177e4 | 1294 | |
b8eed8af | 1295 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1296 | |
0d1857a1 | 1297 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 1298 | |
3a3e9e06 | 1299 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2eaa3e2d | 1300 | |
8414809c SB |
1301 | /* Save the policy somewhere when doing a light-weight tear-down */ |
1302 | if (frozen) | |
3a3e9e06 | 1303 | per_cpu(cpufreq_cpu_data_fallback, cpu) = policy; |
8414809c | 1304 | |
0d1857a1 | 1305 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1306 | |
3a3e9e06 | 1307 | if (!policy) { |
b8eed8af | 1308 | pr_debug("%s: No cpu_data found\n", __func__); |
1da177e4 LT |
1309 | return -EINVAL; |
1310 | } | |
1da177e4 | 1311 | |
9c0ebcf7 | 1312 | if (has_target()) { |
3de9bdeb VK |
1313 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1314 | if (ret) { | |
1315 | pr_err("%s: Failed to stop governor\n", __func__); | |
1316 | return ret; | |
1317 | } | |
1318 | } | |
1da177e4 | 1319 | |
1c3d85dd | 1320 | if (!cpufreq_driver->setpolicy) |
fa69e33f | 1321 | strncpy(per_cpu(cpufreq_cpu_governor, cpu), |
3a3e9e06 | 1322 | policy->governor->name, CPUFREQ_NAME_LEN); |
1da177e4 | 1323 | |
ad7722da | 1324 | down_read(&policy->rwsem); |
3a3e9e06 | 1325 | cpus = cpumask_weight(policy->cpus); |
ad7722da | 1326 | up_read(&policy->rwsem); |
084f3493 | 1327 | |
61173f25 | 1328 | if (cpu != policy->cpu) { |
6964d91d | 1329 | sysfs_remove_link(&dev->kobj, "cpufreq"); |
73bf0fc2 | 1330 | } else if (cpus > 1) { |
42f921a6 | 1331 | new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu); |
f9ba680d | 1332 | if (new_cpu >= 0) { |
3a3e9e06 | 1333 | update_policy_cpu(policy, new_cpu); |
a82fab29 SB |
1334 | |
1335 | if (!frozen) { | |
75949c9a | 1336 | pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n", |
e837f9b5 | 1337 | __func__, new_cpu, cpu); |
a82fab29 | 1338 | } |
1da177e4 LT |
1339 | } |
1340 | } | |
1da177e4 | 1341 | |
cedb70af SB |
1342 | return 0; |
1343 | } | |
1344 | ||
1345 | static int __cpufreq_remove_dev_finish(struct device *dev, | |
1346 | struct subsys_interface *sif, | |
1347 | bool frozen) | |
1348 | { | |
1349 | unsigned int cpu = dev->id, cpus; | |
1350 | int ret; | |
1351 | unsigned long flags; | |
1352 | struct cpufreq_policy *policy; | |
cedb70af SB |
1353 | |
1354 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1355 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1356 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1357 | ||
1358 | if (!policy) { | |
1359 | pr_debug("%s: No cpu_data found\n", __func__); | |
1360 | return -EINVAL; | |
1361 | } | |
1362 | ||
ad7722da | 1363 | down_write(&policy->rwsem); |
cedb70af | 1364 | cpus = cpumask_weight(policy->cpus); |
9c8f1ee4 VK |
1365 | |
1366 | if (cpus > 1) | |
1367 | cpumask_clear_cpu(cpu, policy->cpus); | |
ad7722da | 1368 | up_write(&policy->rwsem); |
cedb70af | 1369 | |
b8eed8af VK |
1370 | /* If cpu is last user of policy, free policy */ |
1371 | if (cpus == 1) { | |
9c0ebcf7 | 1372 | if (has_target()) { |
3de9bdeb VK |
1373 | ret = __cpufreq_governor(policy, |
1374 | CPUFREQ_GOV_POLICY_EXIT); | |
1375 | if (ret) { | |
1376 | pr_err("%s: Failed to exit governor\n", | |
e837f9b5 | 1377 | __func__); |
3de9bdeb VK |
1378 | return ret; |
1379 | } | |
edab2fbc | 1380 | } |
2a998599 | 1381 | |
42f921a6 VK |
1382 | if (!frozen) |
1383 | cpufreq_policy_put_kobj(policy); | |
7d26e2d5 | 1384 | |
8414809c SB |
1385 | /* |
1386 | * Perform the ->exit() even during light-weight tear-down, | |
1387 | * since this is a core component, and is essential for the | |
1388 | * subsequent light-weight ->init() to succeed. | |
b8eed8af | 1389 | */ |
1c3d85dd | 1390 | if (cpufreq_driver->exit) |
3a3e9e06 | 1391 | cpufreq_driver->exit(policy); |
27ecddc2 | 1392 | |
9515f4d6 VK |
1393 | /* Remove policy from list of active policies */ |
1394 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1395 | list_del(&policy->policy_list); | |
1396 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1397 | ||
8414809c | 1398 | if (!frozen) |
3a3e9e06 | 1399 | cpufreq_policy_free(policy); |
2a998599 | 1400 | } else { |
9c0ebcf7 | 1401 | if (has_target()) { |
3de9bdeb VK |
1402 | if ((ret = __cpufreq_governor(policy, CPUFREQ_GOV_START)) || |
1403 | (ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS))) { | |
1404 | pr_err("%s: Failed to start governor\n", | |
e837f9b5 | 1405 | __func__); |
3de9bdeb VK |
1406 | return ret; |
1407 | } | |
2a998599 | 1408 | } |
27ecddc2 | 1409 | } |
1da177e4 | 1410 | |
474deff7 | 1411 | per_cpu(cpufreq_cpu_data, cpu) = NULL; |
1da177e4 LT |
1412 | return 0; |
1413 | } | |
1414 | ||
cedb70af | 1415 | /** |
27a862e9 | 1416 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1417 | * |
1418 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1419 | */ |
8a25a2fd | 1420 | static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1421 | { |
8a25a2fd | 1422 | unsigned int cpu = dev->id; |
27a862e9 | 1423 | int ret; |
ec28297a VP |
1424 | |
1425 | if (cpu_is_offline(cpu)) | |
1426 | return 0; | |
1427 | ||
27a862e9 VK |
1428 | ret = __cpufreq_remove_dev_prepare(dev, sif, false); |
1429 | ||
1430 | if (!ret) | |
1431 | ret = __cpufreq_remove_dev_finish(dev, sif, false); | |
1432 | ||
1433 | return ret; | |
5a01f2e8 VP |
1434 | } |
1435 | ||
65f27f38 | 1436 | static void handle_update(struct work_struct *work) |
1da177e4 | 1437 | { |
65f27f38 DH |
1438 | struct cpufreq_policy *policy = |
1439 | container_of(work, struct cpufreq_policy, update); | |
1440 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1441 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1442 | cpufreq_update_policy(cpu); |
1443 | } | |
1444 | ||
1445 | /** | |
bb176f7d VK |
1446 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1447 | * in deep trouble. | |
1da177e4 LT |
1448 | * @cpu: cpu number |
1449 | * @old_freq: CPU frequency the kernel thinks the CPU runs at | |
1450 | * @new_freq: CPU frequency the CPU actually runs at | |
1451 | * | |
29464f28 DJ |
1452 | * We adjust to current frequency first, and need to clean up later. |
1453 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1454 | */ |
e08f5f5b GS |
1455 | static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, |
1456 | unsigned int new_freq) | |
1da177e4 | 1457 | { |
b43a7ffb | 1458 | struct cpufreq_policy *policy; |
1da177e4 | 1459 | struct cpufreq_freqs freqs; |
b43a7ffb VK |
1460 | unsigned long flags; |
1461 | ||
e837f9b5 JP |
1462 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
1463 | old_freq, new_freq); | |
1da177e4 | 1464 | |
1da177e4 LT |
1465 | freqs.old = old_freq; |
1466 | freqs.new = new_freq; | |
b43a7ffb VK |
1467 | |
1468 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1469 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1470 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1471 | ||
1472 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); | |
1473 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); | |
1da177e4 LT |
1474 | } |
1475 | ||
32ee8c3e | 1476 | /** |
4ab70df4 | 1477 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1478 | * @cpu: CPU number |
1479 | * | |
1480 | * This is the last known freq, without actually getting it from the driver. | |
1481 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1482 | */ | |
1483 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1484 | { | |
9e21ba8b | 1485 | struct cpufreq_policy *policy; |
e08f5f5b | 1486 | unsigned int ret_freq = 0; |
95235ca2 | 1487 | |
1c3d85dd RW |
1488 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1489 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1490 | |
1491 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1492 | if (policy) { |
e08f5f5b | 1493 | ret_freq = policy->cur; |
95235ca2 VP |
1494 | cpufreq_cpu_put(policy); |
1495 | } | |
1496 | ||
4d34a67d | 1497 | return ret_freq; |
95235ca2 VP |
1498 | } |
1499 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1500 | ||
3d737108 JB |
1501 | /** |
1502 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1503 | * @cpu: CPU number | |
1504 | * | |
1505 | * Just return the max possible frequency for a given CPU. | |
1506 | */ | |
1507 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1508 | { | |
1509 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1510 | unsigned int ret_freq = 0; | |
1511 | ||
1512 | if (policy) { | |
1513 | ret_freq = policy->max; | |
1514 | cpufreq_cpu_put(policy); | |
1515 | } | |
1516 | ||
1517 | return ret_freq; | |
1518 | } | |
1519 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1520 | ||
5a01f2e8 | 1521 | static unsigned int __cpufreq_get(unsigned int cpu) |
1da177e4 | 1522 | { |
7a6aedfa | 1523 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
e08f5f5b | 1524 | unsigned int ret_freq = 0; |
5800043b | 1525 | |
1c3d85dd | 1526 | if (!cpufreq_driver->get) |
4d34a67d | 1527 | return ret_freq; |
1da177e4 | 1528 | |
1c3d85dd | 1529 | ret_freq = cpufreq_driver->get(cpu); |
1da177e4 | 1530 | |
e08f5f5b | 1531 | if (ret_freq && policy->cur && |
1c3d85dd | 1532 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1533 | /* verify no discrepancy between actual and |
1534 | saved value exists */ | |
1535 | if (unlikely(ret_freq != policy->cur)) { | |
1536 | cpufreq_out_of_sync(cpu, policy->cur, ret_freq); | |
1da177e4 LT |
1537 | schedule_work(&policy->update); |
1538 | } | |
1539 | } | |
1540 | ||
4d34a67d | 1541 | return ret_freq; |
5a01f2e8 | 1542 | } |
1da177e4 | 1543 | |
5a01f2e8 VP |
1544 | /** |
1545 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1546 | * @cpu: CPU number | |
1547 | * | |
1548 | * Get the CPU current (static) CPU frequency | |
1549 | */ | |
1550 | unsigned int cpufreq_get(unsigned int cpu) | |
1551 | { | |
999976e0 | 1552 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1553 | unsigned int ret_freq = 0; |
5a01f2e8 | 1554 | |
999976e0 AP |
1555 | if (policy) { |
1556 | down_read(&policy->rwsem); | |
1557 | ret_freq = __cpufreq_get(cpu); | |
1558 | up_read(&policy->rwsem); | |
5a01f2e8 | 1559 | |
999976e0 AP |
1560 | cpufreq_cpu_put(policy); |
1561 | } | |
6eed9404 | 1562 | |
4d34a67d | 1563 | return ret_freq; |
1da177e4 LT |
1564 | } |
1565 | EXPORT_SYMBOL(cpufreq_get); | |
1566 | ||
8a25a2fd KS |
1567 | static struct subsys_interface cpufreq_interface = { |
1568 | .name = "cpufreq", | |
1569 | .subsys = &cpu_subsys, | |
1570 | .add_dev = cpufreq_add_dev, | |
1571 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1572 | }; |
1573 | ||
e28867ea VK |
1574 | /* |
1575 | * In case platform wants some specific frequency to be configured | |
1576 | * during suspend.. | |
1577 | */ | |
1578 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1579 | { | |
1580 | int ret; | |
1581 | ||
1582 | if (!policy->suspend_freq) { | |
1583 | pr_err("%s: suspend_freq can't be zero\n", __func__); | |
1584 | return -EINVAL; | |
1585 | } | |
1586 | ||
1587 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1588 | policy->suspend_freq); | |
1589 | ||
1590 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1591 | CPUFREQ_RELATION_H); | |
1592 | if (ret) | |
1593 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1594 | __func__, policy->suspend_freq, ret); | |
1595 | ||
1596 | return ret; | |
1597 | } | |
1598 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1599 | ||
42d4dc3f | 1600 | /** |
2f0aea93 | 1601 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1602 | * |
2f0aea93 VK |
1603 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1604 | * as some platforms can't change frequency after this point in suspend cycle. | |
1605 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1606 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1607 | */ |
2f0aea93 | 1608 | void cpufreq_suspend(void) |
42d4dc3f | 1609 | { |
3a3e9e06 | 1610 | struct cpufreq_policy *policy; |
42d4dc3f | 1611 | |
2f0aea93 VK |
1612 | if (!cpufreq_driver) |
1613 | return; | |
42d4dc3f | 1614 | |
2f0aea93 VK |
1615 | if (!has_target()) |
1616 | return; | |
42d4dc3f | 1617 | |
2f0aea93 VK |
1618 | pr_debug("%s: Suspending Governors\n", __func__); |
1619 | ||
1620 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { | |
1621 | if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP)) | |
1622 | pr_err("%s: Failed to stop governor for policy: %p\n", | |
1623 | __func__, policy); | |
1624 | else if (cpufreq_driver->suspend | |
1625 | && cpufreq_driver->suspend(policy)) | |
1626 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1627 | policy); | |
42d4dc3f BH |
1628 | } |
1629 | ||
2f0aea93 | 1630 | cpufreq_suspended = true; |
42d4dc3f BH |
1631 | } |
1632 | ||
1da177e4 | 1633 | /** |
2f0aea93 | 1634 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1635 | * |
2f0aea93 VK |
1636 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1637 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1638 | */ |
2f0aea93 | 1639 | void cpufreq_resume(void) |
1da177e4 | 1640 | { |
3a3e9e06 | 1641 | struct cpufreq_policy *policy; |
1da177e4 | 1642 | |
2f0aea93 VK |
1643 | if (!cpufreq_driver) |
1644 | return; | |
1da177e4 | 1645 | |
2f0aea93 | 1646 | if (!has_target()) |
e00e56df | 1647 | return; |
1da177e4 | 1648 | |
2f0aea93 | 1649 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1650 | |
2f0aea93 | 1651 | cpufreq_suspended = false; |
ce6c3997 | 1652 | |
2f0aea93 VK |
1653 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { |
1654 | if (__cpufreq_governor(policy, CPUFREQ_GOV_START) | |
1655 | || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS)) | |
1656 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1657 | __func__, policy); | |
1658 | else if (cpufreq_driver->resume | |
1659 | && cpufreq_driver->resume(policy)) | |
1660 | pr_err("%s: Failed to resume driver: %p\n", __func__, | |
1661 | policy); | |
1da177e4 | 1662 | |
2f0aea93 VK |
1663 | /* |
1664 | * schedule call cpufreq_update_policy() for boot CPU, i.e. last | |
1665 | * policy in list. It will verify that the current freq is in | |
1666 | * sync with what we believe it to be. | |
1667 | */ | |
1668 | if (list_is_last(&policy->policy_list, &cpufreq_policy_list)) | |
1669 | schedule_work(&policy->update); | |
1670 | } | |
1671 | } | |
1da177e4 | 1672 | |
9d95046e BP |
1673 | /** |
1674 | * cpufreq_get_current_driver - return current driver's name | |
1675 | * | |
1676 | * Return the name string of the currently loaded cpufreq driver | |
1677 | * or NULL, if none. | |
1678 | */ | |
1679 | const char *cpufreq_get_current_driver(void) | |
1680 | { | |
1c3d85dd RW |
1681 | if (cpufreq_driver) |
1682 | return cpufreq_driver->name; | |
1683 | ||
1684 | return NULL; | |
9d95046e BP |
1685 | } |
1686 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 LT |
1687 | |
1688 | /********************************************************************* | |
1689 | * NOTIFIER LISTS INTERFACE * | |
1690 | *********************************************************************/ | |
1691 | ||
1692 | /** | |
1693 | * cpufreq_register_notifier - register a driver with cpufreq | |
1694 | * @nb: notifier function to register | |
1695 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1696 | * | |
32ee8c3e | 1697 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1698 | * are notified about clock rate changes (once before and once after |
1699 | * the transition), or a list of drivers that are notified about | |
1700 | * changes in cpufreq policy. | |
1701 | * | |
1702 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1703 | * blocking_notifier_chain_register. |
1da177e4 LT |
1704 | */ |
1705 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1706 | { | |
1707 | int ret; | |
1708 | ||
d5aaffa9 DB |
1709 | if (cpufreq_disabled()) |
1710 | return -EINVAL; | |
1711 | ||
74212ca4 CEB |
1712 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1713 | ||
1da177e4 LT |
1714 | switch (list) { |
1715 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1716 | ret = srcu_notifier_chain_register( |
e041c683 | 1717 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1718 | break; |
1719 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1720 | ret = blocking_notifier_chain_register( |
1721 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1722 | break; |
1723 | default: | |
1724 | ret = -EINVAL; | |
1725 | } | |
1da177e4 LT |
1726 | |
1727 | return ret; | |
1728 | } | |
1729 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1730 | ||
1da177e4 LT |
1731 | /** |
1732 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1733 | * @nb: notifier block to be unregistered | |
bb176f7d | 1734 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1735 | * |
1736 | * Remove a driver from the CPU frequency notifier list. | |
1737 | * | |
1738 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1739 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1740 | */ |
1741 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1742 | { | |
1743 | int ret; | |
1744 | ||
d5aaffa9 DB |
1745 | if (cpufreq_disabled()) |
1746 | return -EINVAL; | |
1747 | ||
1da177e4 LT |
1748 | switch (list) { |
1749 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1750 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1751 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1752 | break; |
1753 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1754 | ret = blocking_notifier_chain_unregister( |
1755 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1756 | break; |
1757 | default: | |
1758 | ret = -EINVAL; | |
1759 | } | |
1da177e4 LT |
1760 | |
1761 | return ret; | |
1762 | } | |
1763 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1764 | ||
1765 | ||
1766 | /********************************************************************* | |
1767 | * GOVERNORS * | |
1768 | *********************************************************************/ | |
1769 | ||
1da177e4 LT |
1770 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1771 | unsigned int target_freq, | |
1772 | unsigned int relation) | |
1773 | { | |
1774 | int retval = -EINVAL; | |
7249924e | 1775 | unsigned int old_target_freq = target_freq; |
c32b6b8e | 1776 | |
a7b422cd KRW |
1777 | if (cpufreq_disabled()) |
1778 | return -ENODEV; | |
1779 | ||
7249924e VK |
1780 | /* Make sure that target_freq is within supported range */ |
1781 | if (target_freq > policy->max) | |
1782 | target_freq = policy->max; | |
1783 | if (target_freq < policy->min) | |
1784 | target_freq = policy->min; | |
1785 | ||
1786 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1787 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1788 | |
9c0ebcf7 VK |
1789 | /* |
1790 | * This might look like a redundant call as we are checking it again | |
1791 | * after finding index. But it is left intentionally for cases where | |
1792 | * exactly same freq is called again and so we can save on few function | |
1793 | * calls. | |
1794 | */ | |
5a1c0228 VK |
1795 | if (target_freq == policy->cur) |
1796 | return 0; | |
1797 | ||
1c3d85dd RW |
1798 | if (cpufreq_driver->target) |
1799 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
9c0ebcf7 VK |
1800 | else if (cpufreq_driver->target_index) { |
1801 | struct cpufreq_frequency_table *freq_table; | |
d4019f0a VK |
1802 | struct cpufreq_freqs freqs; |
1803 | bool notify; | |
9c0ebcf7 | 1804 | int index; |
90d45d17 | 1805 | |
9c0ebcf7 VK |
1806 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
1807 | if (unlikely(!freq_table)) { | |
1808 | pr_err("%s: Unable to find freq_table\n", __func__); | |
1809 | goto out; | |
1810 | } | |
1811 | ||
1812 | retval = cpufreq_frequency_table_target(policy, freq_table, | |
1813 | target_freq, relation, &index); | |
1814 | if (unlikely(retval)) { | |
1815 | pr_err("%s: Unable to find matching freq\n", __func__); | |
1816 | goto out; | |
1817 | } | |
1818 | ||
d4019f0a | 1819 | if (freq_table[index].frequency == policy->cur) { |
9c0ebcf7 | 1820 | retval = 0; |
d4019f0a VK |
1821 | goto out; |
1822 | } | |
1823 | ||
1824 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
1825 | ||
1826 | if (notify) { | |
1827 | freqs.old = policy->cur; | |
1828 | freqs.new = freq_table[index].frequency; | |
1829 | freqs.flags = 0; | |
1830 | ||
1831 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", | |
e837f9b5 | 1832 | __func__, policy->cpu, freqs.old, freqs.new); |
d4019f0a VK |
1833 | |
1834 | cpufreq_notify_transition(policy, &freqs, | |
1835 | CPUFREQ_PRECHANGE); | |
1836 | } | |
1837 | ||
1838 | retval = cpufreq_driver->target_index(policy, index); | |
1839 | if (retval) | |
1840 | pr_err("%s: Failed to change cpu frequency: %d\n", | |
e837f9b5 | 1841 | __func__, retval); |
d4019f0a | 1842 | |
ab1b1c4e VK |
1843 | if (notify) |
1844 | cpufreq_notify_post_transition(policy, &freqs, retval); | |
9c0ebcf7 VK |
1845 | } |
1846 | ||
1847 | out: | |
1da177e4 LT |
1848 | return retval; |
1849 | } | |
1850 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1851 | ||
1da177e4 LT |
1852 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1853 | unsigned int target_freq, | |
1854 | unsigned int relation) | |
1855 | { | |
f1829e4a | 1856 | int ret = -EINVAL; |
1da177e4 | 1857 | |
ad7722da | 1858 | down_write(&policy->rwsem); |
1da177e4 LT |
1859 | |
1860 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1861 | ||
ad7722da | 1862 | up_write(&policy->rwsem); |
1da177e4 | 1863 | |
1da177e4 LT |
1864 | return ret; |
1865 | } | |
1866 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1867 | ||
153d7f3f | 1868 | /* |
153d7f3f AV |
1869 | * when "event" is CPUFREQ_GOV_LIMITS |
1870 | */ | |
1da177e4 | 1871 | |
e08f5f5b GS |
1872 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
1873 | unsigned int event) | |
1da177e4 | 1874 | { |
cc993cab | 1875 | int ret; |
6afde10c TR |
1876 | |
1877 | /* Only must be defined when default governor is known to have latency | |
1878 | restrictions, like e.g. conservative or ondemand. | |
1879 | That this is the case is already ensured in Kconfig | |
1880 | */ | |
1881 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
1882 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
1883 | #else | |
1884 | struct cpufreq_governor *gov = NULL; | |
1885 | #endif | |
1c256245 | 1886 | |
2f0aea93 VK |
1887 | /* Don't start any governor operations if we are entering suspend */ |
1888 | if (cpufreq_suspended) | |
1889 | return 0; | |
1890 | ||
1c256245 TR |
1891 | if (policy->governor->max_transition_latency && |
1892 | policy->cpuinfo.transition_latency > | |
1893 | policy->governor->max_transition_latency) { | |
6afde10c TR |
1894 | if (!gov) |
1895 | return -EINVAL; | |
1896 | else { | |
e837f9b5 JP |
1897 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
1898 | policy->governor->name, gov->name); | |
6afde10c TR |
1899 | policy->governor = gov; |
1900 | } | |
1c256245 | 1901 | } |
1da177e4 | 1902 | |
fe492f3f VK |
1903 | if (event == CPUFREQ_GOV_POLICY_INIT) |
1904 | if (!try_module_get(policy->governor->owner)) | |
1905 | return -EINVAL; | |
1da177e4 | 1906 | |
2d06d8c4 | 1907 | pr_debug("__cpufreq_governor for CPU %u, event %u\n", |
e837f9b5 | 1908 | policy->cpu, event); |
95731ebb XC |
1909 | |
1910 | mutex_lock(&cpufreq_governor_lock); | |
56d07db2 | 1911 | if ((policy->governor_enabled && event == CPUFREQ_GOV_START) |
f73d3933 VK |
1912 | || (!policy->governor_enabled |
1913 | && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) { | |
95731ebb XC |
1914 | mutex_unlock(&cpufreq_governor_lock); |
1915 | return -EBUSY; | |
1916 | } | |
1917 | ||
1918 | if (event == CPUFREQ_GOV_STOP) | |
1919 | policy->governor_enabled = false; | |
1920 | else if (event == CPUFREQ_GOV_START) | |
1921 | policy->governor_enabled = true; | |
1922 | ||
1923 | mutex_unlock(&cpufreq_governor_lock); | |
1924 | ||
1da177e4 LT |
1925 | ret = policy->governor->governor(policy, event); |
1926 | ||
4d5dcc42 VK |
1927 | if (!ret) { |
1928 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
1929 | policy->governor->initialized++; | |
1930 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
1931 | policy->governor->initialized--; | |
95731ebb XC |
1932 | } else { |
1933 | /* Restore original values */ | |
1934 | mutex_lock(&cpufreq_governor_lock); | |
1935 | if (event == CPUFREQ_GOV_STOP) | |
1936 | policy->governor_enabled = true; | |
1937 | else if (event == CPUFREQ_GOV_START) | |
1938 | policy->governor_enabled = false; | |
1939 | mutex_unlock(&cpufreq_governor_lock); | |
4d5dcc42 | 1940 | } |
b394058f | 1941 | |
fe492f3f VK |
1942 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
1943 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
1944 | module_put(policy->governor->owner); |
1945 | ||
1946 | return ret; | |
1947 | } | |
1948 | ||
1da177e4 LT |
1949 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
1950 | { | |
3bcb09a3 | 1951 | int err; |
1da177e4 LT |
1952 | |
1953 | if (!governor) | |
1954 | return -EINVAL; | |
1955 | ||
a7b422cd KRW |
1956 | if (cpufreq_disabled()) |
1957 | return -ENODEV; | |
1958 | ||
3fc54d37 | 1959 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 1960 | |
b394058f | 1961 | governor->initialized = 0; |
3bcb09a3 JF |
1962 | err = -EBUSY; |
1963 | if (__find_governor(governor->name) == NULL) { | |
1964 | err = 0; | |
1965 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 1966 | } |
1da177e4 | 1967 | |
32ee8c3e | 1968 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 1969 | return err; |
1da177e4 LT |
1970 | } |
1971 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
1972 | ||
1da177e4 LT |
1973 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
1974 | { | |
90e41bac | 1975 | int cpu; |
90e41bac | 1976 | |
1da177e4 LT |
1977 | if (!governor) |
1978 | return; | |
1979 | ||
a7b422cd KRW |
1980 | if (cpufreq_disabled()) |
1981 | return; | |
1982 | ||
90e41bac PB |
1983 | for_each_present_cpu(cpu) { |
1984 | if (cpu_online(cpu)) | |
1985 | continue; | |
1986 | if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name)) | |
1987 | strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0"); | |
1988 | } | |
90e41bac | 1989 | |
3fc54d37 | 1990 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 1991 | list_del(&governor->governor_list); |
3fc54d37 | 1992 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
1993 | return; |
1994 | } | |
1995 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
1996 | ||
1997 | ||
1da177e4 LT |
1998 | /********************************************************************* |
1999 | * POLICY INTERFACE * | |
2000 | *********************************************************************/ | |
2001 | ||
2002 | /** | |
2003 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2004 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2005 | * is written | |
1da177e4 LT |
2006 | * |
2007 | * Reads the current cpufreq policy. | |
2008 | */ | |
2009 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2010 | { | |
2011 | struct cpufreq_policy *cpu_policy; | |
2012 | if (!policy) | |
2013 | return -EINVAL; | |
2014 | ||
2015 | cpu_policy = cpufreq_cpu_get(cpu); | |
2016 | if (!cpu_policy) | |
2017 | return -EINVAL; | |
2018 | ||
d5b73cd8 | 2019 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2020 | |
2021 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2022 | return 0; |
2023 | } | |
2024 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2025 | ||
153d7f3f | 2026 | /* |
037ce839 VK |
2027 | * policy : current policy. |
2028 | * new_policy: policy to be set. | |
153d7f3f | 2029 | */ |
037ce839 | 2030 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2031 | struct cpufreq_policy *new_policy) |
1da177e4 | 2032 | { |
d9a789c7 RW |
2033 | struct cpufreq_governor *old_gov; |
2034 | int ret; | |
1da177e4 | 2035 | |
e837f9b5 JP |
2036 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2037 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2038 | |
d5b73cd8 | 2039 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2040 | |
d9a789c7 RW |
2041 | if (new_policy->min > policy->max || new_policy->max < policy->min) |
2042 | return -EINVAL; | |
9c9a43ed | 2043 | |
1da177e4 | 2044 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2045 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2046 | if (ret) |
d9a789c7 | 2047 | return ret; |
1da177e4 | 2048 | |
1da177e4 | 2049 | /* adjust if necessary - all reasons */ |
e041c683 | 2050 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2051 | CPUFREQ_ADJUST, new_policy); |
1da177e4 LT |
2052 | |
2053 | /* adjust if necessary - hardware incompatibility*/ | |
e041c683 | 2054 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2055 | CPUFREQ_INCOMPATIBLE, new_policy); |
1da177e4 | 2056 | |
bb176f7d VK |
2057 | /* |
2058 | * verify the cpu speed can be set within this limit, which might be | |
2059 | * different to the first one | |
2060 | */ | |
3a3e9e06 | 2061 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2062 | if (ret) |
d9a789c7 | 2063 | return ret; |
1da177e4 LT |
2064 | |
2065 | /* notification of the new policy */ | |
e041c683 | 2066 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2067 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2068 | |
3a3e9e06 VK |
2069 | policy->min = new_policy->min; |
2070 | policy->max = new_policy->max; | |
1da177e4 | 2071 | |
2d06d8c4 | 2072 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2073 | policy->min, policy->max); |
1da177e4 | 2074 | |
1c3d85dd | 2075 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2076 | policy->policy = new_policy->policy; |
2d06d8c4 | 2077 | pr_debug("setting range\n"); |
d9a789c7 RW |
2078 | return cpufreq_driver->setpolicy(new_policy); |
2079 | } | |
1da177e4 | 2080 | |
d9a789c7 RW |
2081 | if (new_policy->governor == policy->governor) |
2082 | goto out; | |
7bd353a9 | 2083 | |
d9a789c7 RW |
2084 | pr_debug("governor switch\n"); |
2085 | ||
2086 | /* save old, working values */ | |
2087 | old_gov = policy->governor; | |
2088 | /* end old governor */ | |
2089 | if (old_gov) { | |
2090 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
2091 | up_write(&policy->rwsem); | |
2092 | __cpufreq_governor(policy,CPUFREQ_GOV_POLICY_EXIT); | |
2093 | down_write(&policy->rwsem); | |
1da177e4 LT |
2094 | } |
2095 | ||
d9a789c7 RW |
2096 | /* start new governor */ |
2097 | policy->governor = new_policy->governor; | |
2098 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) { | |
2099 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_START)) | |
2100 | goto out; | |
2101 | ||
2102 | up_write(&policy->rwsem); | |
2103 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
2104 | down_write(&policy->rwsem); | |
2105 | } | |
2106 | ||
2107 | /* new governor failed, so re-start old one */ | |
2108 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2109 | if (old_gov) { | |
2110 | policy->governor = old_gov; | |
2111 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); | |
2112 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
2113 | } | |
2114 | ||
2115 | return -EINVAL; | |
2116 | ||
2117 | out: | |
2118 | pr_debug("governor: change or update limits\n"); | |
2119 | return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1da177e4 LT |
2120 | } |
2121 | ||
1da177e4 LT |
2122 | /** |
2123 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2124 | * @cpu: CPU which shall be re-evaluated | |
2125 | * | |
25985edc | 2126 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2127 | * at different times. |
2128 | */ | |
2129 | int cpufreq_update_policy(unsigned int cpu) | |
2130 | { | |
3a3e9e06 VK |
2131 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2132 | struct cpufreq_policy new_policy; | |
f1829e4a | 2133 | int ret; |
1da177e4 | 2134 | |
3a3e9e06 | 2135 | if (!policy) { |
f1829e4a JL |
2136 | ret = -ENODEV; |
2137 | goto no_policy; | |
2138 | } | |
1da177e4 | 2139 | |
ad7722da | 2140 | down_write(&policy->rwsem); |
1da177e4 | 2141 | |
2d06d8c4 | 2142 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2143 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2144 | new_policy.min = policy->user_policy.min; |
2145 | new_policy.max = policy->user_policy.max; | |
2146 | new_policy.policy = policy->user_policy.policy; | |
2147 | new_policy.governor = policy->user_policy.governor; | |
1da177e4 | 2148 | |
bb176f7d VK |
2149 | /* |
2150 | * BIOS might change freq behind our back | |
2151 | * -> ask driver for current freq and notify governors about a change | |
2152 | */ | |
1c3d85dd | 2153 | if (cpufreq_driver->get) { |
3a3e9e06 | 2154 | new_policy.cur = cpufreq_driver->get(cpu); |
bd0fa9bb VK |
2155 | if (WARN_ON(!new_policy.cur)) { |
2156 | ret = -EIO; | |
2157 | goto no_policy; | |
2158 | } | |
2159 | ||
3a3e9e06 | 2160 | if (!policy->cur) { |
e837f9b5 | 2161 | pr_debug("Driver did not initialize current freq\n"); |
3a3e9e06 | 2162 | policy->cur = new_policy.cur; |
a85f7bd3 | 2163 | } else { |
9c0ebcf7 | 2164 | if (policy->cur != new_policy.cur && has_target()) |
3a3e9e06 VK |
2165 | cpufreq_out_of_sync(cpu, policy->cur, |
2166 | new_policy.cur); | |
a85f7bd3 | 2167 | } |
0961dd0d TR |
2168 | } |
2169 | ||
037ce839 | 2170 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2171 | |
ad7722da | 2172 | up_write(&policy->rwsem); |
5a01f2e8 | 2173 | |
3a3e9e06 | 2174 | cpufreq_cpu_put(policy); |
f1829e4a | 2175 | no_policy: |
1da177e4 LT |
2176 | return ret; |
2177 | } | |
2178 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2179 | ||
2760984f | 2180 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2181 | unsigned long action, void *hcpu) |
2182 | { | |
2183 | unsigned int cpu = (unsigned long)hcpu; | |
8a25a2fd | 2184 | struct device *dev; |
5302c3fb | 2185 | bool frozen = false; |
c32b6b8e | 2186 | |
8a25a2fd KS |
2187 | dev = get_cpu_device(cpu); |
2188 | if (dev) { | |
5302c3fb | 2189 | |
d4faadd5 RW |
2190 | if (action & CPU_TASKS_FROZEN) |
2191 | frozen = true; | |
2192 | ||
5302c3fb | 2193 | switch (action & ~CPU_TASKS_FROZEN) { |
c32b6b8e | 2194 | case CPU_ONLINE: |
5302c3fb | 2195 | __cpufreq_add_dev(dev, NULL, frozen); |
c32b6b8e | 2196 | break; |
5302c3fb | 2197 | |
c32b6b8e | 2198 | case CPU_DOWN_PREPARE: |
cedb70af | 2199 | __cpufreq_remove_dev_prepare(dev, NULL, frozen); |
1aee40ac SB |
2200 | break; |
2201 | ||
2202 | case CPU_POST_DEAD: | |
cedb70af | 2203 | __cpufreq_remove_dev_finish(dev, NULL, frozen); |
c32b6b8e | 2204 | break; |
5302c3fb | 2205 | |
5a01f2e8 | 2206 | case CPU_DOWN_FAILED: |
5302c3fb | 2207 | __cpufreq_add_dev(dev, NULL, frozen); |
c32b6b8e AR |
2208 | break; |
2209 | } | |
2210 | } | |
2211 | return NOTIFY_OK; | |
2212 | } | |
2213 | ||
9c36f746 | 2214 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2215 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2216 | }; |
1da177e4 | 2217 | |
6f19efc0 LM |
2218 | /********************************************************************* |
2219 | * BOOST * | |
2220 | *********************************************************************/ | |
2221 | static int cpufreq_boost_set_sw(int state) | |
2222 | { | |
2223 | struct cpufreq_frequency_table *freq_table; | |
2224 | struct cpufreq_policy *policy; | |
2225 | int ret = -EINVAL; | |
2226 | ||
2227 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { | |
2228 | freq_table = cpufreq_frequency_get_table(policy->cpu); | |
2229 | if (freq_table) { | |
2230 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2231 | freq_table); | |
2232 | if (ret) { | |
2233 | pr_err("%s: Policy frequency update failed\n", | |
2234 | __func__); | |
2235 | break; | |
2236 | } | |
2237 | policy->user_policy.max = policy->max; | |
2238 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2239 | } | |
2240 | } | |
2241 | ||
2242 | return ret; | |
2243 | } | |
2244 | ||
2245 | int cpufreq_boost_trigger_state(int state) | |
2246 | { | |
2247 | unsigned long flags; | |
2248 | int ret = 0; | |
2249 | ||
2250 | if (cpufreq_driver->boost_enabled == state) | |
2251 | return 0; | |
2252 | ||
2253 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2254 | cpufreq_driver->boost_enabled = state; | |
2255 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2256 | ||
2257 | ret = cpufreq_driver->set_boost(state); | |
2258 | if (ret) { | |
2259 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2260 | cpufreq_driver->boost_enabled = !state; | |
2261 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2262 | ||
e837f9b5 JP |
2263 | pr_err("%s: Cannot %s BOOST\n", |
2264 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2265 | } |
2266 | ||
2267 | return ret; | |
2268 | } | |
2269 | ||
2270 | int cpufreq_boost_supported(void) | |
2271 | { | |
2272 | if (likely(cpufreq_driver)) | |
2273 | return cpufreq_driver->boost_supported; | |
2274 | ||
2275 | return 0; | |
2276 | } | |
2277 | EXPORT_SYMBOL_GPL(cpufreq_boost_supported); | |
2278 | ||
2279 | int cpufreq_boost_enabled(void) | |
2280 | { | |
2281 | return cpufreq_driver->boost_enabled; | |
2282 | } | |
2283 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2284 | ||
1da177e4 LT |
2285 | /********************************************************************* |
2286 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2287 | *********************************************************************/ | |
2288 | ||
2289 | /** | |
2290 | * cpufreq_register_driver - register a CPU Frequency driver | |
2291 | * @driver_data: A struct cpufreq_driver containing the values# | |
2292 | * submitted by the CPU Frequency driver. | |
2293 | * | |
bb176f7d | 2294 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 2295 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 2296 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2297 | * |
2298 | */ | |
221dee28 | 2299 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2300 | { |
2301 | unsigned long flags; | |
2302 | int ret; | |
2303 | ||
a7b422cd KRW |
2304 | if (cpufreq_disabled()) |
2305 | return -ENODEV; | |
2306 | ||
1da177e4 | 2307 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 VK |
2308 | !(driver_data->setpolicy || driver_data->target_index || |
2309 | driver_data->target)) | |
1da177e4 LT |
2310 | return -EINVAL; |
2311 | ||
2d06d8c4 | 2312 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 LT |
2313 | |
2314 | if (driver_data->setpolicy) | |
2315 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2316 | ||
0d1857a1 | 2317 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2318 | if (cpufreq_driver) { |
0d1857a1 | 2319 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4dea5806 | 2320 | return -EEXIST; |
1da177e4 | 2321 | } |
1c3d85dd | 2322 | cpufreq_driver = driver_data; |
0d1857a1 | 2323 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2324 | |
6f19efc0 LM |
2325 | if (cpufreq_boost_supported()) { |
2326 | /* | |
2327 | * Check if driver provides function to enable boost - | |
2328 | * if not, use cpufreq_boost_set_sw as default | |
2329 | */ | |
2330 | if (!cpufreq_driver->set_boost) | |
2331 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; | |
2332 | ||
2333 | ret = cpufreq_sysfs_create_file(&boost.attr); | |
2334 | if (ret) { | |
2335 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
e837f9b5 | 2336 | __func__); |
6f19efc0 LM |
2337 | goto err_null_driver; |
2338 | } | |
2339 | } | |
2340 | ||
8a25a2fd | 2341 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2342 | if (ret) |
6f19efc0 | 2343 | goto err_boost_unreg; |
1da177e4 | 2344 | |
1c3d85dd | 2345 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) { |
1da177e4 LT |
2346 | int i; |
2347 | ret = -ENODEV; | |
2348 | ||
2349 | /* check for at least one working CPU */ | |
7a6aedfa MT |
2350 | for (i = 0; i < nr_cpu_ids; i++) |
2351 | if (cpu_possible(i) && per_cpu(cpufreq_cpu_data, i)) { | |
1da177e4 | 2352 | ret = 0; |
7a6aedfa MT |
2353 | break; |
2354 | } | |
1da177e4 LT |
2355 | |
2356 | /* if all ->init() calls failed, unregister */ | |
2357 | if (ret) { | |
2d06d8c4 | 2358 | pr_debug("no CPU initialized for driver %s\n", |
e837f9b5 | 2359 | driver_data->name); |
8a25a2fd | 2360 | goto err_if_unreg; |
1da177e4 LT |
2361 | } |
2362 | } | |
2363 | ||
8f5bc2ab | 2364 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2365 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2366 | |
8f5bc2ab | 2367 | return 0; |
8a25a2fd KS |
2368 | err_if_unreg: |
2369 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 LM |
2370 | err_boost_unreg: |
2371 | if (cpufreq_boost_supported()) | |
2372 | cpufreq_sysfs_remove_file(&boost.attr); | |
8f5bc2ab | 2373 | err_null_driver: |
0d1857a1 | 2374 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2375 | cpufreq_driver = NULL; |
0d1857a1 | 2376 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4d34a67d | 2377 | return ret; |
1da177e4 LT |
2378 | } |
2379 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2380 | ||
1da177e4 LT |
2381 | /** |
2382 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2383 | * | |
bb176f7d | 2384 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2385 | * the right to do so, i.e. if you have succeeded in initialising before! |
2386 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2387 | * currently not initialised. | |
2388 | */ | |
221dee28 | 2389 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2390 | { |
2391 | unsigned long flags; | |
2392 | ||
1c3d85dd | 2393 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2394 | return -EINVAL; |
1da177e4 | 2395 | |
2d06d8c4 | 2396 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2397 | |
8a25a2fd | 2398 | subsys_interface_unregister(&cpufreq_interface); |
6f19efc0 LM |
2399 | if (cpufreq_boost_supported()) |
2400 | cpufreq_sysfs_remove_file(&boost.attr); | |
2401 | ||
65edc68c | 2402 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2403 | |
6eed9404 | 2404 | down_write(&cpufreq_rwsem); |
0d1857a1 | 2405 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2406 | |
1c3d85dd | 2407 | cpufreq_driver = NULL; |
6eed9404 | 2408 | |
0d1857a1 | 2409 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
6eed9404 | 2410 | up_write(&cpufreq_rwsem); |
1da177e4 LT |
2411 | |
2412 | return 0; | |
2413 | } | |
2414 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2415 | |
2416 | static int __init cpufreq_core_init(void) | |
2417 | { | |
a7b422cd KRW |
2418 | if (cpufreq_disabled()) |
2419 | return -ENODEV; | |
2420 | ||
2361be23 | 2421 | cpufreq_global_kobject = kobject_create(); |
8aa84ad8 TR |
2422 | BUG_ON(!cpufreq_global_kobject); |
2423 | ||
5a01f2e8 VP |
2424 | return 0; |
2425 | } | |
5a01f2e8 | 2426 | core_initcall(cpufreq_core_init); |