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; | |
1da177e4 | 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 | ||
27e289dc SK |
240 | bool cpufreq_next_valid(struct cpufreq_frequency_table **pos) |
241 | { | |
242 | while ((*pos)->frequency != CPUFREQ_TABLE_END) | |
243 | if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID) | |
244 | return true; | |
245 | else | |
246 | (*pos)++; | |
247 | return false; | |
248 | } | |
249 | EXPORT_SYMBOL_GPL(cpufreq_next_valid); | |
250 | ||
1da177e4 LT |
251 | /********************************************************************* |
252 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
253 | *********************************************************************/ | |
254 | ||
255 | /** | |
256 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
257 | * | |
258 | * This function alters the system "loops_per_jiffy" for the clock | |
259 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 260 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
261 | * per-CPU loops_per_jiffy value wherever possible. |
262 | */ | |
263 | #ifndef CONFIG_SMP | |
264 | static unsigned long l_p_j_ref; | |
bb176f7d | 265 | static unsigned int l_p_j_ref_freq; |
1da177e4 | 266 | |
858119e1 | 267 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 LT |
268 | { |
269 | if (ci->flags & CPUFREQ_CONST_LOOPS) | |
270 | return; | |
271 | ||
272 | if (!l_p_j_ref_freq) { | |
273 | l_p_j_ref = loops_per_jiffy; | |
274 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
275 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
276 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 277 | } |
0b443ead | 278 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
279 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
280 | ci->new); | |
e837f9b5 JP |
281 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
282 | loops_per_jiffy, ci->new); | |
1da177e4 LT |
283 | } |
284 | } | |
285 | #else | |
e08f5f5b GS |
286 | static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
287 | { | |
288 | return; | |
289 | } | |
1da177e4 LT |
290 | #endif |
291 | ||
0956df9c | 292 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 293 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
294 | { |
295 | BUG_ON(irqs_disabled()); | |
296 | ||
d5aaffa9 DB |
297 | if (cpufreq_disabled()) |
298 | return; | |
299 | ||
1c3d85dd | 300 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 301 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 302 | state, freqs->new); |
1da177e4 | 303 | |
1da177e4 | 304 | switch (state) { |
e4472cb3 | 305 | |
1da177e4 | 306 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 307 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
308 | * which is not equal to what the cpufreq core thinks is |
309 | * "old frequency". | |
1da177e4 | 310 | */ |
1c3d85dd | 311 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
312 | if ((policy) && (policy->cpu == freqs->cpu) && |
313 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
314 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
315 | freqs->old, policy->cur); | |
e4472cb3 | 316 | freqs->old = policy->cur; |
1da177e4 LT |
317 | } |
318 | } | |
b4dfdbb3 | 319 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 320 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
321 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
322 | break; | |
e4472cb3 | 323 | |
1da177e4 LT |
324 | case CPUFREQ_POSTCHANGE: |
325 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
326 | pr_debug("FREQ: %lu - CPU: %lu\n", |
327 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 328 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 329 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 330 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
331 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
332 | policy->cur = freqs->new; | |
1da177e4 LT |
333 | break; |
334 | } | |
1da177e4 | 335 | } |
bb176f7d | 336 | |
b43a7ffb VK |
337 | /** |
338 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
339 | * on frequency transition. | |
340 | * | |
341 | * This function calls the transition notifiers and the "adjust_jiffies" | |
342 | * function. It is called twice on all CPU frequency changes that have | |
343 | * external effects. | |
344 | */ | |
236a9800 | 345 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
346 | struct cpufreq_freqs *freqs, unsigned int state) |
347 | { | |
348 | for_each_cpu(freqs->cpu, policy->cpus) | |
349 | __cpufreq_notify_transition(policy, freqs, state); | |
350 | } | |
1da177e4 | 351 | |
f7ba3b41 | 352 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 353 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
354 | struct cpufreq_freqs *freqs, int transition_failed) |
355 | { | |
356 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
357 | if (!transition_failed) | |
358 | return; | |
359 | ||
360 | swap(freqs->old, freqs->new); | |
361 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
362 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
363 | } | |
f7ba3b41 | 364 | |
12478cf0 SB |
365 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
366 | struct cpufreq_freqs *freqs) | |
367 | { | |
368 | wait: | |
369 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
370 | ||
371 | spin_lock(&policy->transition_lock); | |
372 | ||
373 | if (unlikely(policy->transition_ongoing)) { | |
374 | spin_unlock(&policy->transition_lock); | |
375 | goto wait; | |
376 | } | |
377 | ||
378 | policy->transition_ongoing = true; | |
379 | ||
380 | spin_unlock(&policy->transition_lock); | |
381 | ||
382 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
383 | } | |
384 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
385 | ||
386 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
387 | struct cpufreq_freqs *freqs, int transition_failed) | |
388 | { | |
389 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
390 | return; | |
391 | ||
392 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
393 | ||
394 | policy->transition_ongoing = false; | |
395 | ||
396 | wake_up(&policy->transition_wait); | |
397 | } | |
398 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
399 | ||
1da177e4 | 400 | |
1da177e4 LT |
401 | /********************************************************************* |
402 | * SYSFS INTERFACE * | |
403 | *********************************************************************/ | |
8a5c74a1 | 404 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
405 | struct attribute *attr, char *buf) |
406 | { | |
407 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
408 | } | |
409 | ||
410 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
411 | const char *buf, size_t count) | |
412 | { | |
413 | int ret, enable; | |
414 | ||
415 | ret = sscanf(buf, "%d", &enable); | |
416 | if (ret != 1 || enable < 0 || enable > 1) | |
417 | return -EINVAL; | |
418 | ||
419 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
420 | pr_err("%s: Cannot %s BOOST!\n", |
421 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
422 | return -EINVAL; |
423 | } | |
424 | ||
e837f9b5 JP |
425 | pr_debug("%s: cpufreq BOOST %s\n", |
426 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
427 | |
428 | return count; | |
429 | } | |
430 | define_one_global_rw(boost); | |
1da177e4 | 431 | |
3bcb09a3 JF |
432 | static struct cpufreq_governor *__find_governor(const char *str_governor) |
433 | { | |
434 | struct cpufreq_governor *t; | |
435 | ||
436 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) | |
29464f28 | 437 | if (!strnicmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
438 | return t; |
439 | ||
440 | return NULL; | |
441 | } | |
442 | ||
1da177e4 LT |
443 | /** |
444 | * cpufreq_parse_governor - parse a governor string | |
445 | */ | |
905d77cd | 446 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
447 | struct cpufreq_governor **governor) |
448 | { | |
3bcb09a3 | 449 | int err = -EINVAL; |
1c3d85dd RW |
450 | |
451 | if (!cpufreq_driver) | |
3bcb09a3 JF |
452 | goto out; |
453 | ||
1c3d85dd | 454 | if (cpufreq_driver->setpolicy) { |
1da177e4 LT |
455 | if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
456 | *policy = CPUFREQ_POLICY_PERFORMANCE; | |
3bcb09a3 | 457 | err = 0; |
e08f5f5b GS |
458 | } else if (!strnicmp(str_governor, "powersave", |
459 | CPUFREQ_NAME_LEN)) { | |
1da177e4 | 460 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 461 | err = 0; |
1da177e4 | 462 | } |
9c0ebcf7 | 463 | } else if (has_target()) { |
1da177e4 | 464 | struct cpufreq_governor *t; |
3bcb09a3 | 465 | |
3fc54d37 | 466 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 JF |
467 | |
468 | t = __find_governor(str_governor); | |
469 | ||
ea714970 | 470 | if (t == NULL) { |
1a8e1463 | 471 | int ret; |
ea714970 | 472 | |
1a8e1463 KC |
473 | mutex_unlock(&cpufreq_governor_mutex); |
474 | ret = request_module("cpufreq_%s", str_governor); | |
475 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 476 | |
1a8e1463 KC |
477 | if (ret == 0) |
478 | t = __find_governor(str_governor); | |
ea714970 JF |
479 | } |
480 | ||
3bcb09a3 JF |
481 | if (t != NULL) { |
482 | *governor = t; | |
483 | err = 0; | |
1da177e4 | 484 | } |
3bcb09a3 | 485 | |
3fc54d37 | 486 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 487 | } |
29464f28 | 488 | out: |
3bcb09a3 | 489 | return err; |
1da177e4 | 490 | } |
1da177e4 | 491 | |
1da177e4 | 492 | /** |
e08f5f5b GS |
493 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
494 | * print out cpufreq information | |
1da177e4 LT |
495 | * |
496 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
497 | * "unsigned int". | |
498 | */ | |
499 | ||
32ee8c3e DJ |
500 | #define show_one(file_name, object) \ |
501 | static ssize_t show_##file_name \ | |
905d77cd | 502 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 503 | { \ |
29464f28 | 504 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
505 | } |
506 | ||
507 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
508 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 509 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
510 | show_one(scaling_min_freq, min); |
511 | show_one(scaling_max_freq, max); | |
512 | show_one(scaling_cur_freq, cur); | |
513 | ||
037ce839 | 514 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 515 | struct cpufreq_policy *new_policy); |
7970e08b | 516 | |
1da177e4 LT |
517 | /** |
518 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
519 | */ | |
520 | #define store_one(file_name, object) \ | |
521 | static ssize_t store_##file_name \ | |
905d77cd | 522 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 523 | { \ |
5136fa56 | 524 | int ret; \ |
1da177e4 LT |
525 | struct cpufreq_policy new_policy; \ |
526 | \ | |
527 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ | |
528 | if (ret) \ | |
529 | return -EINVAL; \ | |
530 | \ | |
29464f28 | 531 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
532 | if (ret != 1) \ |
533 | return -EINVAL; \ | |
534 | \ | |
037ce839 | 535 | ret = cpufreq_set_policy(policy, &new_policy); \ |
7970e08b | 536 | policy->user_policy.object = policy->object; \ |
1da177e4 LT |
537 | \ |
538 | return ret ? ret : count; \ | |
539 | } | |
540 | ||
29464f28 DJ |
541 | store_one(scaling_min_freq, min); |
542 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
543 | |
544 | /** | |
545 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
546 | */ | |
905d77cd DJ |
547 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
548 | char *buf) | |
1da177e4 | 549 | { |
5a01f2e8 | 550 | unsigned int cur_freq = __cpufreq_get(policy->cpu); |
1da177e4 LT |
551 | if (!cur_freq) |
552 | return sprintf(buf, "<unknown>"); | |
553 | return sprintf(buf, "%u\n", cur_freq); | |
554 | } | |
555 | ||
1da177e4 LT |
556 | /** |
557 | * show_scaling_governor - show the current policy for the specified CPU | |
558 | */ | |
905d77cd | 559 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 560 | { |
29464f28 | 561 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
562 | return sprintf(buf, "powersave\n"); |
563 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
564 | return sprintf(buf, "performance\n"); | |
565 | else if (policy->governor) | |
4b972f0b | 566 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 567 | policy->governor->name); |
1da177e4 LT |
568 | return -EINVAL; |
569 | } | |
570 | ||
1da177e4 LT |
571 | /** |
572 | * store_scaling_governor - store policy for the specified CPU | |
573 | */ | |
905d77cd DJ |
574 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
575 | const char *buf, size_t count) | |
1da177e4 | 576 | { |
5136fa56 | 577 | int ret; |
1da177e4 LT |
578 | char str_governor[16]; |
579 | struct cpufreq_policy new_policy; | |
580 | ||
581 | ret = cpufreq_get_policy(&new_policy, policy->cpu); | |
582 | if (ret) | |
583 | return ret; | |
584 | ||
29464f28 | 585 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
586 | if (ret != 1) |
587 | return -EINVAL; | |
588 | ||
e08f5f5b GS |
589 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
590 | &new_policy.governor)) | |
1da177e4 LT |
591 | return -EINVAL; |
592 | ||
037ce839 | 593 | ret = cpufreq_set_policy(policy, &new_policy); |
7970e08b TR |
594 | |
595 | policy->user_policy.policy = policy->policy; | |
596 | policy->user_policy.governor = policy->governor; | |
7970e08b | 597 | |
e08f5f5b GS |
598 | if (ret) |
599 | return ret; | |
600 | else | |
601 | return count; | |
1da177e4 LT |
602 | } |
603 | ||
604 | /** | |
605 | * show_scaling_driver - show the cpufreq driver currently loaded | |
606 | */ | |
905d77cd | 607 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 608 | { |
1c3d85dd | 609 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
610 | } |
611 | ||
612 | /** | |
613 | * show_scaling_available_governors - show the available CPUfreq governors | |
614 | */ | |
905d77cd DJ |
615 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
616 | char *buf) | |
1da177e4 LT |
617 | { |
618 | ssize_t i = 0; | |
619 | struct cpufreq_governor *t; | |
620 | ||
9c0ebcf7 | 621 | if (!has_target()) { |
1da177e4 LT |
622 | i += sprintf(buf, "performance powersave"); |
623 | goto out; | |
624 | } | |
625 | ||
626 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { | |
29464f28 DJ |
627 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
628 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 629 | goto out; |
4b972f0b | 630 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 631 | } |
7d5e350f | 632 | out: |
1da177e4 LT |
633 | i += sprintf(&buf[i], "\n"); |
634 | return i; | |
635 | } | |
e8628dd0 | 636 | |
f4fd3797 | 637 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
638 | { |
639 | ssize_t i = 0; | |
640 | unsigned int cpu; | |
641 | ||
835481d9 | 642 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
643 | if (i) |
644 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
645 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
646 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 647 | break; |
1da177e4 LT |
648 | } |
649 | i += sprintf(&buf[i], "\n"); | |
650 | return i; | |
651 | } | |
f4fd3797 | 652 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 653 | |
e8628dd0 DW |
654 | /** |
655 | * show_related_cpus - show the CPUs affected by each transition even if | |
656 | * hw coordination is in use | |
657 | */ | |
658 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
659 | { | |
f4fd3797 | 660 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
661 | } |
662 | ||
663 | /** | |
664 | * show_affected_cpus - show the CPUs affected by each transition | |
665 | */ | |
666 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
667 | { | |
f4fd3797 | 668 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
669 | } |
670 | ||
9e76988e | 671 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 672 | const char *buf, size_t count) |
9e76988e VP |
673 | { |
674 | unsigned int freq = 0; | |
675 | unsigned int ret; | |
676 | ||
879000f9 | 677 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
678 | return -EINVAL; |
679 | ||
680 | ret = sscanf(buf, "%u", &freq); | |
681 | if (ret != 1) | |
682 | return -EINVAL; | |
683 | ||
684 | policy->governor->store_setspeed(policy, freq); | |
685 | ||
686 | return count; | |
687 | } | |
688 | ||
689 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
690 | { | |
879000f9 | 691 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
692 | return sprintf(buf, "<unsupported>\n"); |
693 | ||
694 | return policy->governor->show_setspeed(policy, buf); | |
695 | } | |
1da177e4 | 696 | |
e2f74f35 | 697 | /** |
8bf1ac72 | 698 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
699 | */ |
700 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
701 | { | |
702 | unsigned int limit; | |
703 | int ret; | |
1c3d85dd RW |
704 | if (cpufreq_driver->bios_limit) { |
705 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
706 | if (!ret) |
707 | return sprintf(buf, "%u\n", limit); | |
708 | } | |
709 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
710 | } | |
711 | ||
6dad2a29 BP |
712 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
713 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
714 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
715 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
716 | cpufreq_freq_attr_ro(scaling_available_governors); | |
717 | cpufreq_freq_attr_ro(scaling_driver); | |
718 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
719 | cpufreq_freq_attr_ro(bios_limit); | |
720 | cpufreq_freq_attr_ro(related_cpus); | |
721 | cpufreq_freq_attr_ro(affected_cpus); | |
722 | cpufreq_freq_attr_rw(scaling_min_freq); | |
723 | cpufreq_freq_attr_rw(scaling_max_freq); | |
724 | cpufreq_freq_attr_rw(scaling_governor); | |
725 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 726 | |
905d77cd | 727 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
728 | &cpuinfo_min_freq.attr, |
729 | &cpuinfo_max_freq.attr, | |
ed129784 | 730 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
731 | &scaling_min_freq.attr, |
732 | &scaling_max_freq.attr, | |
733 | &affected_cpus.attr, | |
e8628dd0 | 734 | &related_cpus.attr, |
1da177e4 LT |
735 | &scaling_governor.attr, |
736 | &scaling_driver.attr, | |
737 | &scaling_available_governors.attr, | |
9e76988e | 738 | &scaling_setspeed.attr, |
1da177e4 LT |
739 | NULL |
740 | }; | |
741 | ||
29464f28 DJ |
742 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
743 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 744 | |
29464f28 | 745 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 746 | { |
905d77cd DJ |
747 | struct cpufreq_policy *policy = to_policy(kobj); |
748 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 749 | ssize_t ret; |
6eed9404 VK |
750 | |
751 | if (!down_read_trylock(&cpufreq_rwsem)) | |
1b750e3b | 752 | return -EINVAL; |
5a01f2e8 | 753 | |
ad7722da | 754 | down_read(&policy->rwsem); |
5a01f2e8 | 755 | |
e08f5f5b GS |
756 | if (fattr->show) |
757 | ret = fattr->show(policy, buf); | |
758 | else | |
759 | ret = -EIO; | |
760 | ||
ad7722da | 761 | up_read(&policy->rwsem); |
6eed9404 | 762 | up_read(&cpufreq_rwsem); |
1b750e3b | 763 | |
1da177e4 LT |
764 | return ret; |
765 | } | |
766 | ||
905d77cd DJ |
767 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
768 | const char *buf, size_t count) | |
1da177e4 | 769 | { |
905d77cd DJ |
770 | struct cpufreq_policy *policy = to_policy(kobj); |
771 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 772 | ssize_t ret = -EINVAL; |
6eed9404 | 773 | |
4f750c93 SB |
774 | get_online_cpus(); |
775 | ||
776 | if (!cpu_online(policy->cpu)) | |
777 | goto unlock; | |
778 | ||
6eed9404 | 779 | if (!down_read_trylock(&cpufreq_rwsem)) |
4f750c93 | 780 | goto unlock; |
5a01f2e8 | 781 | |
ad7722da | 782 | down_write(&policy->rwsem); |
5a01f2e8 | 783 | |
e08f5f5b GS |
784 | if (fattr->store) |
785 | ret = fattr->store(policy, buf, count); | |
786 | else | |
787 | ret = -EIO; | |
788 | ||
ad7722da | 789 | up_write(&policy->rwsem); |
6eed9404 | 790 | |
6eed9404 | 791 | up_read(&cpufreq_rwsem); |
4f750c93 SB |
792 | unlock: |
793 | put_online_cpus(); | |
794 | ||
1da177e4 LT |
795 | return ret; |
796 | } | |
797 | ||
905d77cd | 798 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 799 | { |
905d77cd | 800 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 801 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
802 | complete(&policy->kobj_unregister); |
803 | } | |
804 | ||
52cf25d0 | 805 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
806 | .show = show, |
807 | .store = store, | |
808 | }; | |
809 | ||
810 | static struct kobj_type ktype_cpufreq = { | |
811 | .sysfs_ops = &sysfs_ops, | |
812 | .default_attrs = default_attrs, | |
813 | .release = cpufreq_sysfs_release, | |
814 | }; | |
815 | ||
2361be23 VK |
816 | struct kobject *cpufreq_global_kobject; |
817 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
818 | ||
819 | static int cpufreq_global_kobject_usage; | |
820 | ||
821 | int cpufreq_get_global_kobject(void) | |
822 | { | |
823 | if (!cpufreq_global_kobject_usage++) | |
824 | return kobject_add(cpufreq_global_kobject, | |
825 | &cpu_subsys.dev_root->kobj, "%s", "cpufreq"); | |
826 | ||
827 | return 0; | |
828 | } | |
829 | EXPORT_SYMBOL(cpufreq_get_global_kobject); | |
830 | ||
831 | void cpufreq_put_global_kobject(void) | |
832 | { | |
833 | if (!--cpufreq_global_kobject_usage) | |
834 | kobject_del(cpufreq_global_kobject); | |
835 | } | |
836 | EXPORT_SYMBOL(cpufreq_put_global_kobject); | |
837 | ||
838 | int cpufreq_sysfs_create_file(const struct attribute *attr) | |
839 | { | |
840 | int ret = cpufreq_get_global_kobject(); | |
841 | ||
842 | if (!ret) { | |
843 | ret = sysfs_create_file(cpufreq_global_kobject, attr); | |
844 | if (ret) | |
845 | cpufreq_put_global_kobject(); | |
846 | } | |
847 | ||
848 | return ret; | |
849 | } | |
850 | EXPORT_SYMBOL(cpufreq_sysfs_create_file); | |
851 | ||
852 | void cpufreq_sysfs_remove_file(const struct attribute *attr) | |
853 | { | |
854 | sysfs_remove_file(cpufreq_global_kobject, attr); | |
855 | cpufreq_put_global_kobject(); | |
856 | } | |
857 | EXPORT_SYMBOL(cpufreq_sysfs_remove_file); | |
858 | ||
19d6f7ec | 859 | /* symlink affected CPUs */ |
308b60e7 | 860 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
861 | { |
862 | unsigned int j; | |
863 | int ret = 0; | |
864 | ||
865 | for_each_cpu(j, policy->cpus) { | |
8a25a2fd | 866 | struct device *cpu_dev; |
19d6f7ec | 867 | |
308b60e7 | 868 | if (j == policy->cpu) |
19d6f7ec | 869 | continue; |
19d6f7ec | 870 | |
e8fdde10 | 871 | pr_debug("Adding link for CPU: %u\n", j); |
8a25a2fd KS |
872 | cpu_dev = get_cpu_device(j); |
873 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
19d6f7ec | 874 | "cpufreq"); |
71c3461e RW |
875 | if (ret) |
876 | break; | |
19d6f7ec DJ |
877 | } |
878 | return ret; | |
879 | } | |
880 | ||
308b60e7 | 881 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy, |
8a25a2fd | 882 | struct device *dev) |
909a694e DJ |
883 | { |
884 | struct freq_attr **drv_attr; | |
909a694e | 885 | int ret = 0; |
909a694e DJ |
886 | |
887 | /* prepare interface data */ | |
888 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, | |
8a25a2fd | 889 | &dev->kobj, "cpufreq"); |
909a694e DJ |
890 | if (ret) |
891 | return ret; | |
892 | ||
893 | /* set up files for this cpu device */ | |
1c3d85dd | 894 | drv_attr = cpufreq_driver->attr; |
909a694e DJ |
895 | while ((drv_attr) && (*drv_attr)) { |
896 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); | |
897 | if (ret) | |
1c3d85dd | 898 | goto err_out_kobj_put; |
909a694e DJ |
899 | drv_attr++; |
900 | } | |
1c3d85dd | 901 | if (cpufreq_driver->get) { |
909a694e DJ |
902 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
903 | if (ret) | |
1c3d85dd | 904 | goto err_out_kobj_put; |
909a694e | 905 | } |
9c0ebcf7 | 906 | if (has_target()) { |
909a694e DJ |
907 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); |
908 | if (ret) | |
1c3d85dd | 909 | goto err_out_kobj_put; |
909a694e | 910 | } |
1c3d85dd | 911 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
912 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
913 | if (ret) | |
1c3d85dd | 914 | goto err_out_kobj_put; |
e2f74f35 | 915 | } |
909a694e | 916 | |
308b60e7 | 917 | ret = cpufreq_add_dev_symlink(policy); |
ecf7e461 DJ |
918 | if (ret) |
919 | goto err_out_kobj_put; | |
920 | ||
e18f1682 SB |
921 | return ret; |
922 | ||
923 | err_out_kobj_put: | |
924 | kobject_put(&policy->kobj); | |
925 | wait_for_completion(&policy->kobj_unregister); | |
926 | return ret; | |
927 | } | |
928 | ||
929 | static void cpufreq_init_policy(struct cpufreq_policy *policy) | |
930 | { | |
6e2c89d1 | 931 | struct cpufreq_governor *gov = NULL; |
e18f1682 SB |
932 | struct cpufreq_policy new_policy; |
933 | int ret = 0; | |
934 | ||
d5b73cd8 | 935 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 936 | |
6e2c89d1 | 937 | /* Update governor of new_policy to the governor used before hotplug */ |
938 | gov = __find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu)); | |
939 | if (gov) | |
940 | pr_debug("Restoring governor %s for cpu %d\n", | |
941 | policy->governor->name, policy->cpu); | |
942 | else | |
943 | gov = CPUFREQ_DEFAULT_GOVERNOR; | |
944 | ||
945 | new_policy.governor = gov; | |
946 | ||
a27a9ab7 JB |
947 | /* Use the default policy if its valid. */ |
948 | if (cpufreq_driver->setpolicy) | |
6e2c89d1 | 949 | cpufreq_parse_governor(gov->name, &new_policy.policy, NULL); |
ecf7e461 DJ |
950 | |
951 | /* set default policy */ | |
037ce839 | 952 | ret = cpufreq_set_policy(policy, &new_policy); |
ecf7e461 | 953 | if (ret) { |
2d06d8c4 | 954 | pr_debug("setting policy failed\n"); |
1c3d85dd RW |
955 | if (cpufreq_driver->exit) |
956 | cpufreq_driver->exit(policy); | |
ecf7e461 | 957 | } |
909a694e DJ |
958 | } |
959 | ||
fcf80582 | 960 | #ifdef CONFIG_HOTPLUG_CPU |
d8d3b471 | 961 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, |
42f921a6 | 962 | unsigned int cpu, struct device *dev) |
fcf80582 | 963 | { |
9c0ebcf7 | 964 | int ret = 0; |
fcf80582 VK |
965 | unsigned long flags; |
966 | ||
9c0ebcf7 | 967 | if (has_target()) { |
3de9bdeb VK |
968 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
969 | if (ret) { | |
970 | pr_err("%s: Failed to stop governor\n", __func__); | |
971 | return ret; | |
972 | } | |
973 | } | |
fcf80582 | 974 | |
ad7722da | 975 | down_write(&policy->rwsem); |
2eaa3e2d | 976 | |
0d1857a1 | 977 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 978 | |
fcf80582 VK |
979 | cpumask_set_cpu(cpu, policy->cpus); |
980 | per_cpu(cpufreq_cpu_data, cpu) = policy; | |
0d1857a1 | 981 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fcf80582 | 982 | |
ad7722da | 983 | up_write(&policy->rwsem); |
2eaa3e2d | 984 | |
9c0ebcf7 | 985 | if (has_target()) { |
e5c87b76 SK |
986 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); |
987 | if (!ret) | |
988 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
989 | ||
990 | if (ret) { | |
3de9bdeb VK |
991 | pr_err("%s: Failed to start governor\n", __func__); |
992 | return ret; | |
993 | } | |
820c6ca2 | 994 | } |
fcf80582 | 995 | |
42f921a6 | 996 | return sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); |
fcf80582 VK |
997 | } |
998 | #endif | |
1da177e4 | 999 | |
8414809c SB |
1000 | static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu) |
1001 | { | |
1002 | struct cpufreq_policy *policy; | |
1003 | unsigned long flags; | |
1004 | ||
44871c9c | 1005 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
8414809c SB |
1006 | |
1007 | policy = per_cpu(cpufreq_cpu_data_fallback, cpu); | |
1008 | ||
44871c9c | 1009 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
8414809c | 1010 | |
6e2c89d1 | 1011 | policy->governor = NULL; |
1012 | ||
8414809c SB |
1013 | return policy; |
1014 | } | |
1015 | ||
e9698cc5 SB |
1016 | static struct cpufreq_policy *cpufreq_policy_alloc(void) |
1017 | { | |
1018 | struct cpufreq_policy *policy; | |
1019 | ||
1020 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); | |
1021 | if (!policy) | |
1022 | return NULL; | |
1023 | ||
1024 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1025 | goto err_free_policy; | |
1026 | ||
1027 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1028 | goto err_free_cpumask; | |
1029 | ||
c88a1f8b | 1030 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1031 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1032 | spin_lock_init(&policy->transition_lock); |
1033 | init_waitqueue_head(&policy->transition_wait); | |
ad7722da | 1034 | |
e9698cc5 SB |
1035 | return policy; |
1036 | ||
1037 | err_free_cpumask: | |
1038 | free_cpumask_var(policy->cpus); | |
1039 | err_free_policy: | |
1040 | kfree(policy); | |
1041 | ||
1042 | return NULL; | |
1043 | } | |
1044 | ||
42f921a6 VK |
1045 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) |
1046 | { | |
1047 | struct kobject *kobj; | |
1048 | struct completion *cmp; | |
1049 | ||
fcd7af91 VK |
1050 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1051 | CPUFREQ_REMOVE_POLICY, policy); | |
1052 | ||
42f921a6 VK |
1053 | down_read(&policy->rwsem); |
1054 | kobj = &policy->kobj; | |
1055 | cmp = &policy->kobj_unregister; | |
1056 | up_read(&policy->rwsem); | |
1057 | kobject_put(kobj); | |
1058 | ||
1059 | /* | |
1060 | * We need to make sure that the underlying kobj is | |
1061 | * actually not referenced anymore by anybody before we | |
1062 | * proceed with unloading. | |
1063 | */ | |
1064 | pr_debug("waiting for dropping of refcount\n"); | |
1065 | wait_for_completion(cmp); | |
1066 | pr_debug("wait complete\n"); | |
1067 | } | |
1068 | ||
e9698cc5 SB |
1069 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
1070 | { | |
1071 | free_cpumask_var(policy->related_cpus); | |
1072 | free_cpumask_var(policy->cpus); | |
1073 | kfree(policy); | |
1074 | } | |
1075 | ||
0d66b91e SB |
1076 | static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
1077 | { | |
99ec899e | 1078 | if (WARN_ON(cpu == policy->cpu)) |
cb38ed5c SB |
1079 | return; |
1080 | ||
ad7722da | 1081 | down_write(&policy->rwsem); |
8efd5765 | 1082 | |
0d66b91e SB |
1083 | policy->last_cpu = policy->cpu; |
1084 | policy->cpu = cpu; | |
1085 | ||
ad7722da | 1086 | up_write(&policy->rwsem); |
8efd5765 | 1087 | |
0d66b91e SB |
1088 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1089 | CPUFREQ_UPDATE_POLICY_CPU, policy); | |
1090 | } | |
1091 | ||
96bbbe4a | 1092 | static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) |
1da177e4 | 1093 | { |
fcf80582 | 1094 | unsigned int j, cpu = dev->id; |
65922465 | 1095 | int ret = -ENOMEM; |
1da177e4 | 1096 | struct cpufreq_policy *policy; |
1da177e4 | 1097 | unsigned long flags; |
96bbbe4a | 1098 | bool recover_policy = cpufreq_suspended; |
90e41bac | 1099 | #ifdef CONFIG_HOTPLUG_CPU |
1b274294 | 1100 | struct cpufreq_policy *tpolicy; |
90e41bac | 1101 | #endif |
1da177e4 | 1102 | |
c32b6b8e AR |
1103 | if (cpu_is_offline(cpu)) |
1104 | return 0; | |
1105 | ||
2d06d8c4 | 1106 | pr_debug("adding CPU %u\n", cpu); |
1da177e4 LT |
1107 | |
1108 | #ifdef CONFIG_SMP | |
1109 | /* check whether a different CPU already registered this | |
1110 | * CPU because it is in the same boat. */ | |
1111 | policy = cpufreq_cpu_get(cpu); | |
1112 | if (unlikely(policy)) { | |
8ff69732 | 1113 | cpufreq_cpu_put(policy); |
1da177e4 LT |
1114 | return 0; |
1115 | } | |
5025d628 | 1116 | #endif |
fcf80582 | 1117 | |
6eed9404 VK |
1118 | if (!down_read_trylock(&cpufreq_rwsem)) |
1119 | return 0; | |
1120 | ||
fcf80582 VK |
1121 | #ifdef CONFIG_HOTPLUG_CPU |
1122 | /* Check if this cpu was hot-unplugged earlier and has siblings */ | |
0d1857a1 | 1123 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1b274294 VK |
1124 | list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) { |
1125 | if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) { | |
0d1857a1 | 1126 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
42f921a6 | 1127 | ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev); |
6eed9404 VK |
1128 | up_read(&cpufreq_rwsem); |
1129 | return ret; | |
2eaa3e2d | 1130 | } |
fcf80582 | 1131 | } |
0d1857a1 | 1132 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
1133 | #endif |
1134 | ||
72368d12 RW |
1135 | /* |
1136 | * Restore the saved policy when doing light-weight init and fall back | |
1137 | * to the full init if that fails. | |
1138 | */ | |
96bbbe4a | 1139 | policy = recover_policy ? cpufreq_policy_restore(cpu) : NULL; |
72368d12 | 1140 | if (!policy) { |
96bbbe4a | 1141 | recover_policy = false; |
8414809c | 1142 | policy = cpufreq_policy_alloc(); |
72368d12 RW |
1143 | if (!policy) |
1144 | goto nomem_out; | |
1145 | } | |
0d66b91e SB |
1146 | |
1147 | /* | |
1148 | * In the resume path, since we restore a saved policy, the assignment | |
1149 | * to policy->cpu is like an update of the existing policy, rather than | |
1150 | * the creation of a brand new one. So we need to perform this update | |
1151 | * by invoking update_policy_cpu(). | |
1152 | */ | |
96bbbe4a | 1153 | if (recover_policy && cpu != policy->cpu) |
0d66b91e SB |
1154 | update_policy_cpu(policy, cpu); |
1155 | else | |
1156 | policy->cpu = cpu; | |
1157 | ||
835481d9 | 1158 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1159 | |
1da177e4 | 1160 | init_completion(&policy->kobj_unregister); |
65f27f38 | 1161 | INIT_WORK(&policy->update, handle_update); |
1da177e4 LT |
1162 | |
1163 | /* call driver. From then on the cpufreq must be able | |
1164 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1165 | */ | |
1c3d85dd | 1166 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1167 | if (ret) { |
2d06d8c4 | 1168 | pr_debug("initialization failed\n"); |
2eaa3e2d | 1169 | goto err_set_policy_cpu; |
1da177e4 | 1170 | } |
643ae6e8 | 1171 | |
5a7e56a5 VK |
1172 | /* related cpus should atleast have policy->cpus */ |
1173 | cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); | |
1174 | ||
1175 | /* | |
1176 | * affected cpus must always be the one, which are online. We aren't | |
1177 | * managing offline cpus here. | |
1178 | */ | |
1179 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1180 | ||
96bbbe4a | 1181 | if (!recover_policy) { |
5a7e56a5 VK |
1182 | policy->user_policy.min = policy->min; |
1183 | policy->user_policy.max = policy->max; | |
1184 | } | |
1185 | ||
4e97b631 | 1186 | down_write(&policy->rwsem); |
652ed95d VK |
1187 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1188 | for_each_cpu(j, policy->cpus) | |
1189 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1190 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1191 | ||
2ed99e39 | 1192 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1193 | policy->cur = cpufreq_driver->get(policy->cpu); |
1194 | if (!policy->cur) { | |
1195 | pr_err("%s: ->get() failed\n", __func__); | |
1196 | goto err_get_freq; | |
1197 | } | |
1198 | } | |
1199 | ||
d3916691 VK |
1200 | /* |
1201 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1202 | * frequency table present with cpufreq core. In such cases CPU might be | |
1203 | * unstable if it has to run on that frequency for long duration of time | |
1204 | * and so its better to set it to a frequency which is specified in | |
1205 | * freq-table. This also makes cpufreq stats inconsistent as | |
1206 | * cpufreq-stats would fail to register because current frequency of CPU | |
1207 | * isn't found in freq-table. | |
1208 | * | |
1209 | * Because we don't want this change to effect boot process badly, we go | |
1210 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1211 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1212 | * is initialized to zero). | |
1213 | * | |
1214 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1215 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1216 | * equal to target-freq. | |
1217 | */ | |
1218 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1219 | && has_target()) { | |
1220 | /* Are we running at unknown frequency ? */ | |
1221 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1222 | if (ret == -EINVAL) { | |
1223 | /* Warn user and fix it */ | |
1224 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1225 | __func__, policy->cpu, policy->cur); | |
1226 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1227 | CPUFREQ_RELATION_L); | |
1228 | ||
1229 | /* | |
1230 | * Reaching here after boot in a few seconds may not | |
1231 | * mean that system will remain stable at "unknown" | |
1232 | * frequency for longer duration. Hence, a BUG_ON(). | |
1233 | */ | |
1234 | BUG_ON(ret); | |
1235 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1236 | __func__, policy->cpu, policy->cur); | |
1237 | } | |
1238 | } | |
1239 | ||
a1531acd TR |
1240 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1241 | CPUFREQ_START, policy); | |
1242 | ||
96bbbe4a | 1243 | if (!recover_policy) { |
308b60e7 | 1244 | ret = cpufreq_add_dev_interface(policy, dev); |
a82fab29 SB |
1245 | if (ret) |
1246 | goto err_out_unregister; | |
fcd7af91 VK |
1247 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1248 | CPUFREQ_CREATE_POLICY, policy); | |
a82fab29 | 1249 | } |
8ff69732 | 1250 | |
9515f4d6 VK |
1251 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1252 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1253 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1254 | ||
e18f1682 SB |
1255 | cpufreq_init_policy(policy); |
1256 | ||
96bbbe4a | 1257 | if (!recover_policy) { |
08fd8c1c VK |
1258 | policy->user_policy.policy = policy->policy; |
1259 | policy->user_policy.governor = policy->governor; | |
1260 | } | |
4e97b631 | 1261 | up_write(&policy->rwsem); |
08fd8c1c | 1262 | |
038c5b3e | 1263 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
6eed9404 VK |
1264 | up_read(&cpufreq_rwsem); |
1265 | ||
2d06d8c4 | 1266 | pr_debug("initialization complete\n"); |
87c32271 | 1267 | |
1da177e4 LT |
1268 | return 0; |
1269 | ||
1da177e4 | 1270 | err_out_unregister: |
652ed95d | 1271 | err_get_freq: |
0d1857a1 | 1272 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
474deff7 | 1273 | for_each_cpu(j, policy->cpus) |
7a6aedfa | 1274 | per_cpu(cpufreq_cpu_data, j) = NULL; |
0d1857a1 | 1275 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1276 | |
da60ce9f VK |
1277 | if (cpufreq_driver->exit) |
1278 | cpufreq_driver->exit(policy); | |
2eaa3e2d | 1279 | err_set_policy_cpu: |
96bbbe4a | 1280 | if (recover_policy) { |
72368d12 RW |
1281 | /* Do not leave stale fallback data behind. */ |
1282 | per_cpu(cpufreq_cpu_data_fallback, cpu) = NULL; | |
42f921a6 | 1283 | cpufreq_policy_put_kobj(policy); |
72368d12 | 1284 | } |
e9698cc5 | 1285 | cpufreq_policy_free(policy); |
42f921a6 | 1286 | |
1da177e4 | 1287 | nomem_out: |
6eed9404 VK |
1288 | up_read(&cpufreq_rwsem); |
1289 | ||
1da177e4 LT |
1290 | return ret; |
1291 | } | |
1292 | ||
a82fab29 SB |
1293 | /** |
1294 | * cpufreq_add_dev - add a CPU device | |
1295 | * | |
1296 | * Adds the cpufreq interface for a CPU device. | |
1297 | * | |
1298 | * The Oracle says: try running cpufreq registration/unregistration concurrently | |
1299 | * with with cpu hotplugging and all hell will break loose. Tried to clean this | |
1300 | * mess up, but more thorough testing is needed. - Mathieu | |
1301 | */ | |
1302 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1303 | { | |
96bbbe4a | 1304 | return __cpufreq_add_dev(dev, sif); |
a82fab29 SB |
1305 | } |
1306 | ||
3a3e9e06 | 1307 | static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, |
42f921a6 | 1308 | unsigned int old_cpu) |
f9ba680d SB |
1309 | { |
1310 | struct device *cpu_dev; | |
f9ba680d SB |
1311 | int ret; |
1312 | ||
1313 | /* first sibling now owns the new sysfs dir */ | |
9c8f1ee4 | 1314 | cpu_dev = get_cpu_device(cpumask_any_but(policy->cpus, old_cpu)); |
a82fab29 | 1315 | |
f9ba680d | 1316 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); |
3a3e9e06 | 1317 | ret = kobject_move(&policy->kobj, &cpu_dev->kobj); |
f9ba680d | 1318 | if (ret) { |
e837f9b5 | 1319 | pr_err("%s: Failed to move kobj: %d\n", __func__, ret); |
f9ba680d | 1320 | |
ad7722da | 1321 | down_write(&policy->rwsem); |
3a3e9e06 | 1322 | cpumask_set_cpu(old_cpu, policy->cpus); |
ad7722da | 1323 | up_write(&policy->rwsem); |
f9ba680d | 1324 | |
3a3e9e06 | 1325 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, |
f9ba680d SB |
1326 | "cpufreq"); |
1327 | ||
1328 | return -EINVAL; | |
1329 | } | |
1330 | ||
1331 | return cpu_dev->id; | |
1332 | } | |
1333 | ||
cedb70af | 1334 | static int __cpufreq_remove_dev_prepare(struct device *dev, |
96bbbe4a | 1335 | struct subsys_interface *sif) |
1da177e4 | 1336 | { |
f9ba680d | 1337 | unsigned int cpu = dev->id, cpus; |
3de9bdeb | 1338 | int new_cpu, ret; |
1da177e4 | 1339 | unsigned long flags; |
3a3e9e06 | 1340 | struct cpufreq_policy *policy; |
1da177e4 | 1341 | |
b8eed8af | 1342 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1343 | |
0d1857a1 | 1344 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 1345 | |
3a3e9e06 | 1346 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2eaa3e2d | 1347 | |
8414809c | 1348 | /* Save the policy somewhere when doing a light-weight tear-down */ |
96bbbe4a | 1349 | if (cpufreq_suspended) |
3a3e9e06 | 1350 | per_cpu(cpufreq_cpu_data_fallback, cpu) = policy; |
8414809c | 1351 | |
0d1857a1 | 1352 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1353 | |
3a3e9e06 | 1354 | if (!policy) { |
b8eed8af | 1355 | pr_debug("%s: No cpu_data found\n", __func__); |
1da177e4 LT |
1356 | return -EINVAL; |
1357 | } | |
1da177e4 | 1358 | |
9c0ebcf7 | 1359 | if (has_target()) { |
3de9bdeb VK |
1360 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1361 | if (ret) { | |
1362 | pr_err("%s: Failed to stop governor\n", __func__); | |
1363 | return ret; | |
1364 | } | |
1365 | } | |
1da177e4 | 1366 | |
1c3d85dd | 1367 | if (!cpufreq_driver->setpolicy) |
fa69e33f | 1368 | strncpy(per_cpu(cpufreq_cpu_governor, cpu), |
3a3e9e06 | 1369 | policy->governor->name, CPUFREQ_NAME_LEN); |
1da177e4 | 1370 | |
ad7722da | 1371 | down_read(&policy->rwsem); |
3a3e9e06 | 1372 | cpus = cpumask_weight(policy->cpus); |
ad7722da | 1373 | up_read(&policy->rwsem); |
084f3493 | 1374 | |
61173f25 | 1375 | if (cpu != policy->cpu) { |
6964d91d | 1376 | sysfs_remove_link(&dev->kobj, "cpufreq"); |
73bf0fc2 | 1377 | } else if (cpus > 1) { |
42f921a6 | 1378 | new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu); |
f9ba680d | 1379 | if (new_cpu >= 0) { |
3a3e9e06 | 1380 | update_policy_cpu(policy, new_cpu); |
a82fab29 | 1381 | |
bda9f552 | 1382 | if (!cpufreq_suspended) |
75949c9a | 1383 | pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n", |
e837f9b5 | 1384 | __func__, new_cpu, cpu); |
1da177e4 | 1385 | } |
367dc4aa DB |
1386 | } else if (cpufreq_driver->stop_cpu && cpufreq_driver->setpolicy) { |
1387 | cpufreq_driver->stop_cpu(policy); | |
1da177e4 | 1388 | } |
1da177e4 | 1389 | |
cedb70af SB |
1390 | return 0; |
1391 | } | |
1392 | ||
1393 | static int __cpufreq_remove_dev_finish(struct device *dev, | |
96bbbe4a | 1394 | struct subsys_interface *sif) |
cedb70af SB |
1395 | { |
1396 | unsigned int cpu = dev->id, cpus; | |
1397 | int ret; | |
1398 | unsigned long flags; | |
1399 | struct cpufreq_policy *policy; | |
cedb70af SB |
1400 | |
1401 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1402 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1403 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1404 | ||
1405 | if (!policy) { | |
1406 | pr_debug("%s: No cpu_data found\n", __func__); | |
1407 | return -EINVAL; | |
1408 | } | |
1409 | ||
ad7722da | 1410 | down_write(&policy->rwsem); |
cedb70af | 1411 | cpus = cpumask_weight(policy->cpus); |
9c8f1ee4 VK |
1412 | |
1413 | if (cpus > 1) | |
1414 | cpumask_clear_cpu(cpu, policy->cpus); | |
ad7722da | 1415 | up_write(&policy->rwsem); |
cedb70af | 1416 | |
b8eed8af VK |
1417 | /* If cpu is last user of policy, free policy */ |
1418 | if (cpus == 1) { | |
9c0ebcf7 | 1419 | if (has_target()) { |
3de9bdeb VK |
1420 | ret = __cpufreq_governor(policy, |
1421 | CPUFREQ_GOV_POLICY_EXIT); | |
1422 | if (ret) { | |
1423 | pr_err("%s: Failed to exit governor\n", | |
e837f9b5 | 1424 | __func__); |
3de9bdeb VK |
1425 | return ret; |
1426 | } | |
edab2fbc | 1427 | } |
2a998599 | 1428 | |
96bbbe4a | 1429 | if (!cpufreq_suspended) |
42f921a6 | 1430 | cpufreq_policy_put_kobj(policy); |
7d26e2d5 | 1431 | |
8414809c SB |
1432 | /* |
1433 | * Perform the ->exit() even during light-weight tear-down, | |
1434 | * since this is a core component, and is essential for the | |
1435 | * subsequent light-weight ->init() to succeed. | |
b8eed8af | 1436 | */ |
1c3d85dd | 1437 | if (cpufreq_driver->exit) |
3a3e9e06 | 1438 | cpufreq_driver->exit(policy); |
27ecddc2 | 1439 | |
9515f4d6 VK |
1440 | /* Remove policy from list of active policies */ |
1441 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1442 | list_del(&policy->policy_list); | |
1443 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1444 | ||
96bbbe4a | 1445 | if (!cpufreq_suspended) |
3a3e9e06 | 1446 | cpufreq_policy_free(policy); |
e5c87b76 SK |
1447 | } else if (has_target()) { |
1448 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
1449 | if (!ret) | |
1450 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1451 | ||
1452 | if (ret) { | |
1453 | pr_err("%s: Failed to start governor\n", __func__); | |
1454 | return ret; | |
2a998599 | 1455 | } |
27ecddc2 | 1456 | } |
1da177e4 | 1457 | |
474deff7 | 1458 | per_cpu(cpufreq_cpu_data, cpu) = NULL; |
1da177e4 LT |
1459 | return 0; |
1460 | } | |
1461 | ||
cedb70af | 1462 | /** |
27a862e9 | 1463 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1464 | * |
1465 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1466 | */ |
8a25a2fd | 1467 | static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1468 | { |
8a25a2fd | 1469 | unsigned int cpu = dev->id; |
27a862e9 | 1470 | int ret; |
ec28297a VP |
1471 | |
1472 | if (cpu_is_offline(cpu)) | |
1473 | return 0; | |
1474 | ||
96bbbe4a | 1475 | ret = __cpufreq_remove_dev_prepare(dev, sif); |
27a862e9 VK |
1476 | |
1477 | if (!ret) | |
96bbbe4a | 1478 | ret = __cpufreq_remove_dev_finish(dev, sif); |
27a862e9 VK |
1479 | |
1480 | return ret; | |
5a01f2e8 VP |
1481 | } |
1482 | ||
65f27f38 | 1483 | static void handle_update(struct work_struct *work) |
1da177e4 | 1484 | { |
65f27f38 DH |
1485 | struct cpufreq_policy *policy = |
1486 | container_of(work, struct cpufreq_policy, update); | |
1487 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1488 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1489 | cpufreq_update_policy(cpu); |
1490 | } | |
1491 | ||
1492 | /** | |
bb176f7d VK |
1493 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1494 | * in deep trouble. | |
1da177e4 LT |
1495 | * @cpu: cpu number |
1496 | * @old_freq: CPU frequency the kernel thinks the CPU runs at | |
1497 | * @new_freq: CPU frequency the CPU actually runs at | |
1498 | * | |
29464f28 DJ |
1499 | * We adjust to current frequency first, and need to clean up later. |
1500 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1501 | */ |
e08f5f5b GS |
1502 | static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, |
1503 | unsigned int new_freq) | |
1da177e4 | 1504 | { |
b43a7ffb | 1505 | struct cpufreq_policy *policy; |
1da177e4 | 1506 | struct cpufreq_freqs freqs; |
b43a7ffb VK |
1507 | unsigned long flags; |
1508 | ||
e837f9b5 JP |
1509 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
1510 | old_freq, new_freq); | |
1da177e4 | 1511 | |
1da177e4 LT |
1512 | freqs.old = old_freq; |
1513 | freqs.new = new_freq; | |
b43a7ffb VK |
1514 | |
1515 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1516 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1517 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1518 | ||
8fec051e VK |
1519 | cpufreq_freq_transition_begin(policy, &freqs); |
1520 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1521 | } |
1522 | ||
32ee8c3e | 1523 | /** |
4ab70df4 | 1524 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1525 | * @cpu: CPU number |
1526 | * | |
1527 | * This is the last known freq, without actually getting it from the driver. | |
1528 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1529 | */ | |
1530 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1531 | { | |
9e21ba8b | 1532 | struct cpufreq_policy *policy; |
e08f5f5b | 1533 | unsigned int ret_freq = 0; |
95235ca2 | 1534 | |
1c3d85dd RW |
1535 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1536 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1537 | |
1538 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1539 | if (policy) { |
e08f5f5b | 1540 | ret_freq = policy->cur; |
95235ca2 VP |
1541 | cpufreq_cpu_put(policy); |
1542 | } | |
1543 | ||
4d34a67d | 1544 | return ret_freq; |
95235ca2 VP |
1545 | } |
1546 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1547 | ||
3d737108 JB |
1548 | /** |
1549 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1550 | * @cpu: CPU number | |
1551 | * | |
1552 | * Just return the max possible frequency for a given CPU. | |
1553 | */ | |
1554 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1555 | { | |
1556 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1557 | unsigned int ret_freq = 0; | |
1558 | ||
1559 | if (policy) { | |
1560 | ret_freq = policy->max; | |
1561 | cpufreq_cpu_put(policy); | |
1562 | } | |
1563 | ||
1564 | return ret_freq; | |
1565 | } | |
1566 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1567 | ||
5a01f2e8 | 1568 | static unsigned int __cpufreq_get(unsigned int cpu) |
1da177e4 | 1569 | { |
7a6aedfa | 1570 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
e08f5f5b | 1571 | unsigned int ret_freq = 0; |
5800043b | 1572 | |
1c3d85dd | 1573 | if (!cpufreq_driver->get) |
4d34a67d | 1574 | return ret_freq; |
1da177e4 | 1575 | |
1c3d85dd | 1576 | ret_freq = cpufreq_driver->get(cpu); |
1da177e4 | 1577 | |
e08f5f5b | 1578 | if (ret_freq && policy->cur && |
1c3d85dd | 1579 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1580 | /* verify no discrepancy between actual and |
1581 | saved value exists */ | |
1582 | if (unlikely(ret_freq != policy->cur)) { | |
1583 | cpufreq_out_of_sync(cpu, policy->cur, ret_freq); | |
1da177e4 LT |
1584 | schedule_work(&policy->update); |
1585 | } | |
1586 | } | |
1587 | ||
4d34a67d | 1588 | return ret_freq; |
5a01f2e8 | 1589 | } |
1da177e4 | 1590 | |
5a01f2e8 VP |
1591 | /** |
1592 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1593 | * @cpu: CPU number | |
1594 | * | |
1595 | * Get the CPU current (static) CPU frequency | |
1596 | */ | |
1597 | unsigned int cpufreq_get(unsigned int cpu) | |
1598 | { | |
999976e0 | 1599 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1600 | unsigned int ret_freq = 0; |
5a01f2e8 | 1601 | |
999976e0 AP |
1602 | if (policy) { |
1603 | down_read(&policy->rwsem); | |
1604 | ret_freq = __cpufreq_get(cpu); | |
1605 | up_read(&policy->rwsem); | |
5a01f2e8 | 1606 | |
999976e0 AP |
1607 | cpufreq_cpu_put(policy); |
1608 | } | |
6eed9404 | 1609 | |
4d34a67d | 1610 | return ret_freq; |
1da177e4 LT |
1611 | } |
1612 | EXPORT_SYMBOL(cpufreq_get); | |
1613 | ||
8a25a2fd KS |
1614 | static struct subsys_interface cpufreq_interface = { |
1615 | .name = "cpufreq", | |
1616 | .subsys = &cpu_subsys, | |
1617 | .add_dev = cpufreq_add_dev, | |
1618 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1619 | }; |
1620 | ||
e28867ea VK |
1621 | /* |
1622 | * In case platform wants some specific frequency to be configured | |
1623 | * during suspend.. | |
1624 | */ | |
1625 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1626 | { | |
1627 | int ret; | |
1628 | ||
1629 | if (!policy->suspend_freq) { | |
1630 | pr_err("%s: suspend_freq can't be zero\n", __func__); | |
1631 | return -EINVAL; | |
1632 | } | |
1633 | ||
1634 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1635 | policy->suspend_freq); | |
1636 | ||
1637 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1638 | CPUFREQ_RELATION_H); | |
1639 | if (ret) | |
1640 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1641 | __func__, policy->suspend_freq, ret); | |
1642 | ||
1643 | return ret; | |
1644 | } | |
1645 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1646 | ||
42d4dc3f | 1647 | /** |
2f0aea93 | 1648 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1649 | * |
2f0aea93 VK |
1650 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1651 | * as some platforms can't change frequency after this point in suspend cycle. | |
1652 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1653 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1654 | */ |
2f0aea93 | 1655 | void cpufreq_suspend(void) |
42d4dc3f | 1656 | { |
3a3e9e06 | 1657 | struct cpufreq_policy *policy; |
42d4dc3f | 1658 | |
2f0aea93 VK |
1659 | if (!cpufreq_driver) |
1660 | return; | |
42d4dc3f | 1661 | |
2f0aea93 VK |
1662 | if (!has_target()) |
1663 | return; | |
42d4dc3f | 1664 | |
2f0aea93 VK |
1665 | pr_debug("%s: Suspending Governors\n", __func__); |
1666 | ||
1667 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { | |
1668 | if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP)) | |
1669 | pr_err("%s: Failed to stop governor for policy: %p\n", | |
1670 | __func__, policy); | |
1671 | else if (cpufreq_driver->suspend | |
1672 | && cpufreq_driver->suspend(policy)) | |
1673 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1674 | policy); | |
42d4dc3f BH |
1675 | } |
1676 | ||
2f0aea93 | 1677 | cpufreq_suspended = true; |
42d4dc3f BH |
1678 | } |
1679 | ||
1da177e4 | 1680 | /** |
2f0aea93 | 1681 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1682 | * |
2f0aea93 VK |
1683 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1684 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1685 | */ |
2f0aea93 | 1686 | void cpufreq_resume(void) |
1da177e4 | 1687 | { |
3a3e9e06 | 1688 | struct cpufreq_policy *policy; |
1da177e4 | 1689 | |
2f0aea93 VK |
1690 | if (!cpufreq_driver) |
1691 | return; | |
1da177e4 | 1692 | |
2f0aea93 | 1693 | if (!has_target()) |
e00e56df | 1694 | return; |
1da177e4 | 1695 | |
2f0aea93 | 1696 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1697 | |
2f0aea93 | 1698 | cpufreq_suspended = false; |
ce6c3997 | 1699 | |
2f0aea93 | 1700 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { |
0c5aa405 VK |
1701 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) |
1702 | pr_err("%s: Failed to resume driver: %p\n", __func__, | |
1703 | policy); | |
1704 | else if (__cpufreq_governor(policy, CPUFREQ_GOV_START) | |
2f0aea93 VK |
1705 | || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS)) |
1706 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1707 | __func__, policy); | |
1da177e4 | 1708 | |
2f0aea93 VK |
1709 | /* |
1710 | * schedule call cpufreq_update_policy() for boot CPU, i.e. last | |
1711 | * policy in list. It will verify that the current freq is in | |
1712 | * sync with what we believe it to be. | |
1713 | */ | |
1714 | if (list_is_last(&policy->policy_list, &cpufreq_policy_list)) | |
1715 | schedule_work(&policy->update); | |
1716 | } | |
1717 | } | |
1da177e4 | 1718 | |
9d95046e BP |
1719 | /** |
1720 | * cpufreq_get_current_driver - return current driver's name | |
1721 | * | |
1722 | * Return the name string of the currently loaded cpufreq driver | |
1723 | * or NULL, if none. | |
1724 | */ | |
1725 | const char *cpufreq_get_current_driver(void) | |
1726 | { | |
1c3d85dd RW |
1727 | if (cpufreq_driver) |
1728 | return cpufreq_driver->name; | |
1729 | ||
1730 | return NULL; | |
9d95046e BP |
1731 | } |
1732 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 LT |
1733 | |
1734 | /********************************************************************* | |
1735 | * NOTIFIER LISTS INTERFACE * | |
1736 | *********************************************************************/ | |
1737 | ||
1738 | /** | |
1739 | * cpufreq_register_notifier - register a driver with cpufreq | |
1740 | * @nb: notifier function to register | |
1741 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1742 | * | |
32ee8c3e | 1743 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1744 | * are notified about clock rate changes (once before and once after |
1745 | * the transition), or a list of drivers that are notified about | |
1746 | * changes in cpufreq policy. | |
1747 | * | |
1748 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1749 | * blocking_notifier_chain_register. |
1da177e4 LT |
1750 | */ |
1751 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1752 | { | |
1753 | int ret; | |
1754 | ||
d5aaffa9 DB |
1755 | if (cpufreq_disabled()) |
1756 | return -EINVAL; | |
1757 | ||
74212ca4 CEB |
1758 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1759 | ||
1da177e4 LT |
1760 | switch (list) { |
1761 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1762 | ret = srcu_notifier_chain_register( |
e041c683 | 1763 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1764 | break; |
1765 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1766 | ret = blocking_notifier_chain_register( |
1767 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1768 | break; |
1769 | default: | |
1770 | ret = -EINVAL; | |
1771 | } | |
1da177e4 LT |
1772 | |
1773 | return ret; | |
1774 | } | |
1775 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1776 | ||
1da177e4 LT |
1777 | /** |
1778 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1779 | * @nb: notifier block to be unregistered | |
bb176f7d | 1780 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1781 | * |
1782 | * Remove a driver from the CPU frequency notifier list. | |
1783 | * | |
1784 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1785 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1786 | */ |
1787 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1788 | { | |
1789 | int ret; | |
1790 | ||
d5aaffa9 DB |
1791 | if (cpufreq_disabled()) |
1792 | return -EINVAL; | |
1793 | ||
1da177e4 LT |
1794 | switch (list) { |
1795 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1796 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1797 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1798 | break; |
1799 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1800 | ret = blocking_notifier_chain_unregister( |
1801 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1802 | break; |
1803 | default: | |
1804 | ret = -EINVAL; | |
1805 | } | |
1da177e4 LT |
1806 | |
1807 | return ret; | |
1808 | } | |
1809 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1810 | ||
1811 | ||
1812 | /********************************************************************* | |
1813 | * GOVERNORS * | |
1814 | *********************************************************************/ | |
1815 | ||
1da177e4 LT |
1816 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1817 | unsigned int target_freq, | |
1818 | unsigned int relation) | |
1819 | { | |
1820 | int retval = -EINVAL; | |
7249924e | 1821 | unsigned int old_target_freq = target_freq; |
c32b6b8e | 1822 | |
a7b422cd KRW |
1823 | if (cpufreq_disabled()) |
1824 | return -ENODEV; | |
1825 | ||
7249924e VK |
1826 | /* Make sure that target_freq is within supported range */ |
1827 | if (target_freq > policy->max) | |
1828 | target_freq = policy->max; | |
1829 | if (target_freq < policy->min) | |
1830 | target_freq = policy->min; | |
1831 | ||
1832 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1833 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1834 | |
9c0ebcf7 VK |
1835 | /* |
1836 | * This might look like a redundant call as we are checking it again | |
1837 | * after finding index. But it is left intentionally for cases where | |
1838 | * exactly same freq is called again and so we can save on few function | |
1839 | * calls. | |
1840 | */ | |
5a1c0228 VK |
1841 | if (target_freq == policy->cur) |
1842 | return 0; | |
1843 | ||
1c3d85dd RW |
1844 | if (cpufreq_driver->target) |
1845 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
9c0ebcf7 VK |
1846 | else if (cpufreq_driver->target_index) { |
1847 | struct cpufreq_frequency_table *freq_table; | |
d4019f0a VK |
1848 | struct cpufreq_freqs freqs; |
1849 | bool notify; | |
9c0ebcf7 | 1850 | int index; |
90d45d17 | 1851 | |
9c0ebcf7 VK |
1852 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
1853 | if (unlikely(!freq_table)) { | |
1854 | pr_err("%s: Unable to find freq_table\n", __func__); | |
1855 | goto out; | |
1856 | } | |
1857 | ||
1858 | retval = cpufreq_frequency_table_target(policy, freq_table, | |
1859 | target_freq, relation, &index); | |
1860 | if (unlikely(retval)) { | |
1861 | pr_err("%s: Unable to find matching freq\n", __func__); | |
1862 | goto out; | |
1863 | } | |
1864 | ||
d4019f0a | 1865 | if (freq_table[index].frequency == policy->cur) { |
9c0ebcf7 | 1866 | retval = 0; |
d4019f0a VK |
1867 | goto out; |
1868 | } | |
1869 | ||
1870 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
1871 | ||
1872 | if (notify) { | |
1873 | freqs.old = policy->cur; | |
1874 | freqs.new = freq_table[index].frequency; | |
1875 | freqs.flags = 0; | |
1876 | ||
1877 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", | |
e837f9b5 | 1878 | __func__, policy->cpu, freqs.old, freqs.new); |
d4019f0a | 1879 | |
8fec051e | 1880 | cpufreq_freq_transition_begin(policy, &freqs); |
d4019f0a VK |
1881 | } |
1882 | ||
1883 | retval = cpufreq_driver->target_index(policy, index); | |
1884 | if (retval) | |
1885 | pr_err("%s: Failed to change cpu frequency: %d\n", | |
e837f9b5 | 1886 | __func__, retval); |
d4019f0a | 1887 | |
ab1b1c4e | 1888 | if (notify) |
8fec051e | 1889 | cpufreq_freq_transition_end(policy, &freqs, retval); |
9c0ebcf7 VK |
1890 | } |
1891 | ||
1892 | out: | |
1da177e4 LT |
1893 | return retval; |
1894 | } | |
1895 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1896 | ||
1da177e4 LT |
1897 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1898 | unsigned int target_freq, | |
1899 | unsigned int relation) | |
1900 | { | |
f1829e4a | 1901 | int ret = -EINVAL; |
1da177e4 | 1902 | |
ad7722da | 1903 | down_write(&policy->rwsem); |
1da177e4 LT |
1904 | |
1905 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1906 | ||
ad7722da | 1907 | up_write(&policy->rwsem); |
1da177e4 | 1908 | |
1da177e4 LT |
1909 | return ret; |
1910 | } | |
1911 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1912 | ||
153d7f3f | 1913 | /* |
153d7f3f AV |
1914 | * when "event" is CPUFREQ_GOV_LIMITS |
1915 | */ | |
1da177e4 | 1916 | |
e08f5f5b GS |
1917 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
1918 | unsigned int event) | |
1da177e4 | 1919 | { |
cc993cab | 1920 | int ret; |
6afde10c TR |
1921 | |
1922 | /* Only must be defined when default governor is known to have latency | |
1923 | restrictions, like e.g. conservative or ondemand. | |
1924 | That this is the case is already ensured in Kconfig | |
1925 | */ | |
1926 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
1927 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
1928 | #else | |
1929 | struct cpufreq_governor *gov = NULL; | |
1930 | #endif | |
1c256245 | 1931 | |
2f0aea93 VK |
1932 | /* Don't start any governor operations if we are entering suspend */ |
1933 | if (cpufreq_suspended) | |
1934 | return 0; | |
1935 | ||
1c256245 TR |
1936 | if (policy->governor->max_transition_latency && |
1937 | policy->cpuinfo.transition_latency > | |
1938 | policy->governor->max_transition_latency) { | |
6afde10c TR |
1939 | if (!gov) |
1940 | return -EINVAL; | |
1941 | else { | |
e837f9b5 JP |
1942 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
1943 | policy->governor->name, gov->name); | |
6afde10c TR |
1944 | policy->governor = gov; |
1945 | } | |
1c256245 | 1946 | } |
1da177e4 | 1947 | |
fe492f3f VK |
1948 | if (event == CPUFREQ_GOV_POLICY_INIT) |
1949 | if (!try_module_get(policy->governor->owner)) | |
1950 | return -EINVAL; | |
1da177e4 | 1951 | |
2d06d8c4 | 1952 | pr_debug("__cpufreq_governor for CPU %u, event %u\n", |
e837f9b5 | 1953 | policy->cpu, event); |
95731ebb XC |
1954 | |
1955 | mutex_lock(&cpufreq_governor_lock); | |
56d07db2 | 1956 | if ((policy->governor_enabled && event == CPUFREQ_GOV_START) |
f73d3933 VK |
1957 | || (!policy->governor_enabled |
1958 | && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) { | |
95731ebb XC |
1959 | mutex_unlock(&cpufreq_governor_lock); |
1960 | return -EBUSY; | |
1961 | } | |
1962 | ||
1963 | if (event == CPUFREQ_GOV_STOP) | |
1964 | policy->governor_enabled = false; | |
1965 | else if (event == CPUFREQ_GOV_START) | |
1966 | policy->governor_enabled = true; | |
1967 | ||
1968 | mutex_unlock(&cpufreq_governor_lock); | |
1969 | ||
1da177e4 LT |
1970 | ret = policy->governor->governor(policy, event); |
1971 | ||
4d5dcc42 VK |
1972 | if (!ret) { |
1973 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
1974 | policy->governor->initialized++; | |
1975 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
1976 | policy->governor->initialized--; | |
95731ebb XC |
1977 | } else { |
1978 | /* Restore original values */ | |
1979 | mutex_lock(&cpufreq_governor_lock); | |
1980 | if (event == CPUFREQ_GOV_STOP) | |
1981 | policy->governor_enabled = true; | |
1982 | else if (event == CPUFREQ_GOV_START) | |
1983 | policy->governor_enabled = false; | |
1984 | mutex_unlock(&cpufreq_governor_lock); | |
4d5dcc42 | 1985 | } |
b394058f | 1986 | |
fe492f3f VK |
1987 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
1988 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
1989 | module_put(policy->governor->owner); |
1990 | ||
1991 | return ret; | |
1992 | } | |
1993 | ||
1da177e4 LT |
1994 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
1995 | { | |
3bcb09a3 | 1996 | int err; |
1da177e4 LT |
1997 | |
1998 | if (!governor) | |
1999 | return -EINVAL; | |
2000 | ||
a7b422cd KRW |
2001 | if (cpufreq_disabled()) |
2002 | return -ENODEV; | |
2003 | ||
3fc54d37 | 2004 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2005 | |
b394058f | 2006 | governor->initialized = 0; |
3bcb09a3 JF |
2007 | err = -EBUSY; |
2008 | if (__find_governor(governor->name) == NULL) { | |
2009 | err = 0; | |
2010 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2011 | } |
1da177e4 | 2012 | |
32ee8c3e | 2013 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2014 | return err; |
1da177e4 LT |
2015 | } |
2016 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2017 | ||
1da177e4 LT |
2018 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2019 | { | |
90e41bac | 2020 | int cpu; |
90e41bac | 2021 | |
1da177e4 LT |
2022 | if (!governor) |
2023 | return; | |
2024 | ||
a7b422cd KRW |
2025 | if (cpufreq_disabled()) |
2026 | return; | |
2027 | ||
90e41bac PB |
2028 | for_each_present_cpu(cpu) { |
2029 | if (cpu_online(cpu)) | |
2030 | continue; | |
2031 | if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name)) | |
2032 | strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0"); | |
2033 | } | |
90e41bac | 2034 | |
3fc54d37 | 2035 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2036 | list_del(&governor->governor_list); |
3fc54d37 | 2037 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2038 | return; |
2039 | } | |
2040 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2041 | ||
2042 | ||
1da177e4 LT |
2043 | /********************************************************************* |
2044 | * POLICY INTERFACE * | |
2045 | *********************************************************************/ | |
2046 | ||
2047 | /** | |
2048 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2049 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2050 | * is written | |
1da177e4 LT |
2051 | * |
2052 | * Reads the current cpufreq policy. | |
2053 | */ | |
2054 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2055 | { | |
2056 | struct cpufreq_policy *cpu_policy; | |
2057 | if (!policy) | |
2058 | return -EINVAL; | |
2059 | ||
2060 | cpu_policy = cpufreq_cpu_get(cpu); | |
2061 | if (!cpu_policy) | |
2062 | return -EINVAL; | |
2063 | ||
d5b73cd8 | 2064 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2065 | |
2066 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2067 | return 0; |
2068 | } | |
2069 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2070 | ||
153d7f3f | 2071 | /* |
037ce839 VK |
2072 | * policy : current policy. |
2073 | * new_policy: policy to be set. | |
153d7f3f | 2074 | */ |
037ce839 | 2075 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2076 | struct cpufreq_policy *new_policy) |
1da177e4 | 2077 | { |
d9a789c7 RW |
2078 | struct cpufreq_governor *old_gov; |
2079 | int ret; | |
1da177e4 | 2080 | |
e837f9b5 JP |
2081 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2082 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2083 | |
d5b73cd8 | 2084 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2085 | |
d9a789c7 RW |
2086 | if (new_policy->min > policy->max || new_policy->max < policy->min) |
2087 | return -EINVAL; | |
9c9a43ed | 2088 | |
1da177e4 | 2089 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2090 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2091 | if (ret) |
d9a789c7 | 2092 | return ret; |
1da177e4 | 2093 | |
1da177e4 | 2094 | /* adjust if necessary - all reasons */ |
e041c683 | 2095 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2096 | CPUFREQ_ADJUST, new_policy); |
1da177e4 LT |
2097 | |
2098 | /* adjust if necessary - hardware incompatibility*/ | |
e041c683 | 2099 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2100 | CPUFREQ_INCOMPATIBLE, new_policy); |
1da177e4 | 2101 | |
bb176f7d VK |
2102 | /* |
2103 | * verify the cpu speed can be set within this limit, which might be | |
2104 | * different to the first one | |
2105 | */ | |
3a3e9e06 | 2106 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2107 | if (ret) |
d9a789c7 | 2108 | return ret; |
1da177e4 LT |
2109 | |
2110 | /* notification of the new policy */ | |
e041c683 | 2111 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2112 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2113 | |
3a3e9e06 VK |
2114 | policy->min = new_policy->min; |
2115 | policy->max = new_policy->max; | |
1da177e4 | 2116 | |
2d06d8c4 | 2117 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2118 | policy->min, policy->max); |
1da177e4 | 2119 | |
1c3d85dd | 2120 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2121 | policy->policy = new_policy->policy; |
2d06d8c4 | 2122 | pr_debug("setting range\n"); |
d9a789c7 RW |
2123 | return cpufreq_driver->setpolicy(new_policy); |
2124 | } | |
1da177e4 | 2125 | |
d9a789c7 RW |
2126 | if (new_policy->governor == policy->governor) |
2127 | goto out; | |
7bd353a9 | 2128 | |
d9a789c7 RW |
2129 | pr_debug("governor switch\n"); |
2130 | ||
2131 | /* save old, working values */ | |
2132 | old_gov = policy->governor; | |
2133 | /* end old governor */ | |
2134 | if (old_gov) { | |
2135 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
2136 | up_write(&policy->rwsem); | |
e5c87b76 | 2137 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
d9a789c7 | 2138 | down_write(&policy->rwsem); |
1da177e4 LT |
2139 | } |
2140 | ||
d9a789c7 RW |
2141 | /* start new governor */ |
2142 | policy->governor = new_policy->governor; | |
2143 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) { | |
2144 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_START)) | |
2145 | goto out; | |
2146 | ||
2147 | up_write(&policy->rwsem); | |
2148 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
2149 | down_write(&policy->rwsem); | |
2150 | } | |
2151 | ||
2152 | /* new governor failed, so re-start old one */ | |
2153 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2154 | if (old_gov) { | |
2155 | policy->governor = old_gov; | |
2156 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); | |
2157 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
2158 | } | |
2159 | ||
2160 | return -EINVAL; | |
2161 | ||
2162 | out: | |
2163 | pr_debug("governor: change or update limits\n"); | |
2164 | return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1da177e4 LT |
2165 | } |
2166 | ||
1da177e4 LT |
2167 | /** |
2168 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2169 | * @cpu: CPU which shall be re-evaluated | |
2170 | * | |
25985edc | 2171 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2172 | * at different times. |
2173 | */ | |
2174 | int cpufreq_update_policy(unsigned int cpu) | |
2175 | { | |
3a3e9e06 VK |
2176 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2177 | struct cpufreq_policy new_policy; | |
f1829e4a | 2178 | int ret; |
1da177e4 | 2179 | |
3a3e9e06 | 2180 | if (!policy) { |
f1829e4a JL |
2181 | ret = -ENODEV; |
2182 | goto no_policy; | |
2183 | } | |
1da177e4 | 2184 | |
ad7722da | 2185 | down_write(&policy->rwsem); |
1da177e4 | 2186 | |
2d06d8c4 | 2187 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2188 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2189 | new_policy.min = policy->user_policy.min; |
2190 | new_policy.max = policy->user_policy.max; | |
2191 | new_policy.policy = policy->user_policy.policy; | |
2192 | new_policy.governor = policy->user_policy.governor; | |
1da177e4 | 2193 | |
bb176f7d VK |
2194 | /* |
2195 | * BIOS might change freq behind our back | |
2196 | * -> ask driver for current freq and notify governors about a change | |
2197 | */ | |
2ed99e39 | 2198 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
3a3e9e06 | 2199 | new_policy.cur = cpufreq_driver->get(cpu); |
bd0fa9bb VK |
2200 | if (WARN_ON(!new_policy.cur)) { |
2201 | ret = -EIO; | |
2202 | goto no_policy; | |
2203 | } | |
2204 | ||
3a3e9e06 | 2205 | if (!policy->cur) { |
e837f9b5 | 2206 | pr_debug("Driver did not initialize current freq\n"); |
3a3e9e06 | 2207 | policy->cur = new_policy.cur; |
a85f7bd3 | 2208 | } else { |
9c0ebcf7 | 2209 | if (policy->cur != new_policy.cur && has_target()) |
3a3e9e06 VK |
2210 | cpufreq_out_of_sync(cpu, policy->cur, |
2211 | new_policy.cur); | |
a85f7bd3 | 2212 | } |
0961dd0d TR |
2213 | } |
2214 | ||
037ce839 | 2215 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2216 | |
ad7722da | 2217 | up_write(&policy->rwsem); |
5a01f2e8 | 2218 | |
3a3e9e06 | 2219 | cpufreq_cpu_put(policy); |
f1829e4a | 2220 | no_policy: |
1da177e4 LT |
2221 | return ret; |
2222 | } | |
2223 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2224 | ||
2760984f | 2225 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2226 | unsigned long action, void *hcpu) |
2227 | { | |
2228 | unsigned int cpu = (unsigned long)hcpu; | |
8a25a2fd | 2229 | struct device *dev; |
c32b6b8e | 2230 | |
8a25a2fd KS |
2231 | dev = get_cpu_device(cpu); |
2232 | if (dev) { | |
5302c3fb | 2233 | switch (action & ~CPU_TASKS_FROZEN) { |
c32b6b8e | 2234 | case CPU_ONLINE: |
96bbbe4a | 2235 | __cpufreq_add_dev(dev, NULL); |
c32b6b8e | 2236 | break; |
5302c3fb | 2237 | |
c32b6b8e | 2238 | case CPU_DOWN_PREPARE: |
96bbbe4a | 2239 | __cpufreq_remove_dev_prepare(dev, NULL); |
1aee40ac SB |
2240 | break; |
2241 | ||
2242 | case CPU_POST_DEAD: | |
96bbbe4a | 2243 | __cpufreq_remove_dev_finish(dev, NULL); |
c32b6b8e | 2244 | break; |
5302c3fb | 2245 | |
5a01f2e8 | 2246 | case CPU_DOWN_FAILED: |
96bbbe4a | 2247 | __cpufreq_add_dev(dev, NULL); |
c32b6b8e AR |
2248 | break; |
2249 | } | |
2250 | } | |
2251 | return NOTIFY_OK; | |
2252 | } | |
2253 | ||
9c36f746 | 2254 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2255 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2256 | }; |
1da177e4 | 2257 | |
6f19efc0 LM |
2258 | /********************************************************************* |
2259 | * BOOST * | |
2260 | *********************************************************************/ | |
2261 | static int cpufreq_boost_set_sw(int state) | |
2262 | { | |
2263 | struct cpufreq_frequency_table *freq_table; | |
2264 | struct cpufreq_policy *policy; | |
2265 | int ret = -EINVAL; | |
2266 | ||
2267 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { | |
2268 | freq_table = cpufreq_frequency_get_table(policy->cpu); | |
2269 | if (freq_table) { | |
2270 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2271 | freq_table); | |
2272 | if (ret) { | |
2273 | pr_err("%s: Policy frequency update failed\n", | |
2274 | __func__); | |
2275 | break; | |
2276 | } | |
2277 | policy->user_policy.max = policy->max; | |
2278 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2279 | } | |
2280 | } | |
2281 | ||
2282 | return ret; | |
2283 | } | |
2284 | ||
2285 | int cpufreq_boost_trigger_state(int state) | |
2286 | { | |
2287 | unsigned long flags; | |
2288 | int ret = 0; | |
2289 | ||
2290 | if (cpufreq_driver->boost_enabled == state) | |
2291 | return 0; | |
2292 | ||
2293 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2294 | cpufreq_driver->boost_enabled = state; | |
2295 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2296 | ||
2297 | ret = cpufreq_driver->set_boost(state); | |
2298 | if (ret) { | |
2299 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2300 | cpufreq_driver->boost_enabled = !state; | |
2301 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2302 | ||
e837f9b5 JP |
2303 | pr_err("%s: Cannot %s BOOST\n", |
2304 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2305 | } |
2306 | ||
2307 | return ret; | |
2308 | } | |
2309 | ||
2310 | int cpufreq_boost_supported(void) | |
2311 | { | |
2312 | if (likely(cpufreq_driver)) | |
2313 | return cpufreq_driver->boost_supported; | |
2314 | ||
2315 | return 0; | |
2316 | } | |
2317 | EXPORT_SYMBOL_GPL(cpufreq_boost_supported); | |
2318 | ||
2319 | int cpufreq_boost_enabled(void) | |
2320 | { | |
2321 | return cpufreq_driver->boost_enabled; | |
2322 | } | |
2323 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2324 | ||
1da177e4 LT |
2325 | /********************************************************************* |
2326 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2327 | *********************************************************************/ | |
2328 | ||
2329 | /** | |
2330 | * cpufreq_register_driver - register a CPU Frequency driver | |
2331 | * @driver_data: A struct cpufreq_driver containing the values# | |
2332 | * submitted by the CPU Frequency driver. | |
2333 | * | |
bb176f7d | 2334 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 2335 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 2336 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2337 | * |
2338 | */ | |
221dee28 | 2339 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2340 | { |
2341 | unsigned long flags; | |
2342 | int ret; | |
2343 | ||
a7b422cd KRW |
2344 | if (cpufreq_disabled()) |
2345 | return -ENODEV; | |
2346 | ||
1da177e4 | 2347 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2348 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2349 | driver_data->target) || |
2350 | (driver_data->setpolicy && (driver_data->target_index || | |
2351 | driver_data->target))) | |
1da177e4 LT |
2352 | return -EINVAL; |
2353 | ||
2d06d8c4 | 2354 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 LT |
2355 | |
2356 | if (driver_data->setpolicy) | |
2357 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2358 | ||
0d1857a1 | 2359 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2360 | if (cpufreq_driver) { |
0d1857a1 | 2361 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4dea5806 | 2362 | return -EEXIST; |
1da177e4 | 2363 | } |
1c3d85dd | 2364 | cpufreq_driver = driver_data; |
0d1857a1 | 2365 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2366 | |
6f19efc0 LM |
2367 | if (cpufreq_boost_supported()) { |
2368 | /* | |
2369 | * Check if driver provides function to enable boost - | |
2370 | * if not, use cpufreq_boost_set_sw as default | |
2371 | */ | |
2372 | if (!cpufreq_driver->set_boost) | |
2373 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; | |
2374 | ||
2375 | ret = cpufreq_sysfs_create_file(&boost.attr); | |
2376 | if (ret) { | |
2377 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
e837f9b5 | 2378 | __func__); |
6f19efc0 LM |
2379 | goto err_null_driver; |
2380 | } | |
2381 | } | |
2382 | ||
8a25a2fd | 2383 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2384 | if (ret) |
6f19efc0 | 2385 | goto err_boost_unreg; |
1da177e4 | 2386 | |
1c3d85dd | 2387 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) { |
1da177e4 LT |
2388 | int i; |
2389 | ret = -ENODEV; | |
2390 | ||
2391 | /* check for at least one working CPU */ | |
7a6aedfa MT |
2392 | for (i = 0; i < nr_cpu_ids; i++) |
2393 | if (cpu_possible(i) && per_cpu(cpufreq_cpu_data, i)) { | |
1da177e4 | 2394 | ret = 0; |
7a6aedfa MT |
2395 | break; |
2396 | } | |
1da177e4 LT |
2397 | |
2398 | /* if all ->init() calls failed, unregister */ | |
2399 | if (ret) { | |
2d06d8c4 | 2400 | pr_debug("no CPU initialized for driver %s\n", |
e837f9b5 | 2401 | driver_data->name); |
8a25a2fd | 2402 | goto err_if_unreg; |
1da177e4 LT |
2403 | } |
2404 | } | |
2405 | ||
8f5bc2ab | 2406 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2407 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2408 | |
8f5bc2ab | 2409 | return 0; |
8a25a2fd KS |
2410 | err_if_unreg: |
2411 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 LM |
2412 | err_boost_unreg: |
2413 | if (cpufreq_boost_supported()) | |
2414 | cpufreq_sysfs_remove_file(&boost.attr); | |
8f5bc2ab | 2415 | err_null_driver: |
0d1857a1 | 2416 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2417 | cpufreq_driver = NULL; |
0d1857a1 | 2418 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4d34a67d | 2419 | return ret; |
1da177e4 LT |
2420 | } |
2421 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2422 | ||
1da177e4 LT |
2423 | /** |
2424 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2425 | * | |
bb176f7d | 2426 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2427 | * the right to do so, i.e. if you have succeeded in initialising before! |
2428 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2429 | * currently not initialised. | |
2430 | */ | |
221dee28 | 2431 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2432 | { |
2433 | unsigned long flags; | |
2434 | ||
1c3d85dd | 2435 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2436 | return -EINVAL; |
1da177e4 | 2437 | |
2d06d8c4 | 2438 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2439 | |
8a25a2fd | 2440 | subsys_interface_unregister(&cpufreq_interface); |
6f19efc0 LM |
2441 | if (cpufreq_boost_supported()) |
2442 | cpufreq_sysfs_remove_file(&boost.attr); | |
2443 | ||
65edc68c | 2444 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2445 | |
6eed9404 | 2446 | down_write(&cpufreq_rwsem); |
0d1857a1 | 2447 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2448 | |
1c3d85dd | 2449 | cpufreq_driver = NULL; |
6eed9404 | 2450 | |
0d1857a1 | 2451 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
6eed9404 | 2452 | up_write(&cpufreq_rwsem); |
1da177e4 LT |
2453 | |
2454 | return 0; | |
2455 | } | |
2456 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2457 | |
2458 | static int __init cpufreq_core_init(void) | |
2459 | { | |
a7b422cd KRW |
2460 | if (cpufreq_disabled()) |
2461 | return -ENODEV; | |
2462 | ||
2361be23 | 2463 | cpufreq_global_kobject = kobject_create(); |
8aa84ad8 TR |
2464 | BUG_ON(!cpufreq_global_kobject); |
2465 | ||
5a01f2e8 VP |
2466 | return 0; |
2467 | } | |
5a01f2e8 | 2468 | core_initcall(cpufreq_core_init); |