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> | |
6 | * | |
c32b6b8e | 7 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 8 | * Added handling for CPU hotplug |
8ff69732 DJ |
9 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
10 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 11 | * |
1da177e4 LT |
12 | * This program is free software; you can redistribute it and/or modify |
13 | * it under the terms of the GNU General Public License version 2 as | |
14 | * published by the Free Software Foundation. | |
15 | * | |
16 | */ | |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
72a4ce34 | 20 | #include <asm/cputime.h> |
1da177e4 | 21 | #include <linux/kernel.h> |
72a4ce34 | 22 | #include <linux/kernel_stat.h> |
1da177e4 LT |
23 | #include <linux/module.h> |
24 | #include <linux/init.h> | |
25 | #include <linux/notifier.h> | |
26 | #include <linux/cpufreq.h> | |
27 | #include <linux/delay.h> | |
28 | #include <linux/interrupt.h> | |
29 | #include <linux/spinlock.h> | |
72a4ce34 | 30 | #include <linux/tick.h> |
1da177e4 LT |
31 | #include <linux/device.h> |
32 | #include <linux/slab.h> | |
33 | #include <linux/cpu.h> | |
34 | #include <linux/completion.h> | |
3fc54d37 | 35 | #include <linux/mutex.h> |
e00e56df | 36 | #include <linux/syscore_ops.h> |
1da177e4 | 37 | |
6f4f2723 TR |
38 | #include <trace/events/power.h> |
39 | ||
1da177e4 | 40 | /** |
cd878479 | 41 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
42 | * level driver of CPUFreq support, and its spinlock. This lock |
43 | * also protects the cpufreq_cpu_data array. | |
44 | */ | |
1c3d85dd | 45 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 46 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
084f3493 TR |
47 | #ifdef CONFIG_HOTPLUG_CPU |
48 | /* This one keeps track of the previously set governor of a removed CPU */ | |
e77b89f1 | 49 | static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor); |
084f3493 | 50 | #endif |
0d1857a1 | 51 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
1da177e4 | 52 | |
5a01f2e8 VP |
53 | /* |
54 | * cpu_policy_rwsem is a per CPU reader-writer semaphore designed to cure | |
55 | * all cpufreq/hotplug/workqueue/etc related lock issues. | |
56 | * | |
57 | * The rules for this semaphore: | |
58 | * - Any routine that wants to read from the policy structure will | |
59 | * do a down_read on this semaphore. | |
60 | * - Any routine that will write to the policy structure and/or may take away | |
61 | * the policy altogether (eg. CPU hotplug), will hold this lock in write | |
62 | * mode before doing so. | |
63 | * | |
64 | * Additional rules: | |
5a01f2e8 VP |
65 | * - Governor routines that can be called in cpufreq hotplug path should not |
66 | * take this sem as top level hotplug notifier handler takes this. | |
395913d0 MD |
67 | * - Lock should not be held across |
68 | * __cpufreq_governor(data, CPUFREQ_GOV_STOP); | |
5a01f2e8 | 69 | */ |
f1625066 | 70 | static DEFINE_PER_CPU(int, cpufreq_policy_cpu); |
5a01f2e8 VP |
71 | static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem); |
72 | ||
73 | #define lock_policy_rwsem(mode, cpu) \ | |
fa1d8af4 | 74 | static int lock_policy_rwsem_##mode(int cpu) \ |
5a01f2e8 | 75 | { \ |
f1625066 | 76 | int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu); \ |
5a01f2e8 VP |
77 | BUG_ON(policy_cpu == -1); \ |
78 | down_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \ | |
5a01f2e8 VP |
79 | \ |
80 | return 0; \ | |
81 | } | |
82 | ||
83 | lock_policy_rwsem(read, cpu); | |
5a01f2e8 | 84 | lock_policy_rwsem(write, cpu); |
5a01f2e8 | 85 | |
fa1d8af4 VK |
86 | #define unlock_policy_rwsem(mode, cpu) \ |
87 | static void unlock_policy_rwsem_##mode(int cpu) \ | |
88 | { \ | |
89 | int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu); \ | |
90 | BUG_ON(policy_cpu == -1); \ | |
91 | up_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \ | |
5a01f2e8 | 92 | } |
5a01f2e8 | 93 | |
fa1d8af4 VK |
94 | unlock_policy_rwsem(read, cpu); |
95 | unlock_policy_rwsem(write, cpu); | |
5a01f2e8 | 96 | |
1da177e4 | 97 | /* internal prototypes */ |
29464f28 DJ |
98 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
99 | unsigned int event); | |
5a01f2e8 | 100 | static unsigned int __cpufreq_get(unsigned int cpu); |
65f27f38 | 101 | static void handle_update(struct work_struct *work); |
1da177e4 LT |
102 | |
103 | /** | |
32ee8c3e DJ |
104 | * Two notifier lists: the "policy" list is involved in the |
105 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
106 | * "transition" list for kernel code that needs to handle |
107 | * changes to devices when the CPU clock speed changes. | |
108 | * The mutex locks both lists. | |
109 | */ | |
e041c683 | 110 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 111 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 112 | |
74212ca4 | 113 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
114 | static int __init init_cpufreq_transition_notifier_list(void) |
115 | { | |
116 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 117 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
118 | return 0; |
119 | } | |
b3438f82 | 120 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 121 | |
a7b422cd | 122 | static int off __read_mostly; |
da584455 | 123 | static int cpufreq_disabled(void) |
a7b422cd KRW |
124 | { |
125 | return off; | |
126 | } | |
127 | void disable_cpufreq(void) | |
128 | { | |
129 | off = 1; | |
130 | } | |
1da177e4 | 131 | static LIST_HEAD(cpufreq_governor_list); |
29464f28 | 132 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 133 | |
4d5dcc42 VK |
134 | bool have_governor_per_policy(void) |
135 | { | |
1c3d85dd | 136 | return cpufreq_driver->have_governor_per_policy; |
4d5dcc42 | 137 | } |
3f869d6d | 138 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 139 | |
944e9a03 VK |
140 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
141 | { | |
142 | if (have_governor_per_policy()) | |
143 | return &policy->kobj; | |
144 | else | |
145 | return cpufreq_global_kobject; | |
146 | } | |
147 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
148 | ||
72a4ce34 VK |
149 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
150 | { | |
151 | u64 idle_time; | |
152 | u64 cur_wall_time; | |
153 | u64 busy_time; | |
154 | ||
155 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
156 | ||
157 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
158 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
159 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
160 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
161 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
162 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
163 | ||
164 | idle_time = cur_wall_time - busy_time; | |
165 | if (wall) | |
166 | *wall = cputime_to_usecs(cur_wall_time); | |
167 | ||
168 | return cputime_to_usecs(idle_time); | |
169 | } | |
170 | ||
171 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
172 | { | |
173 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
174 | ||
175 | if (idle_time == -1ULL) | |
176 | return get_cpu_idle_time_jiffy(cpu, wall); | |
177 | else if (!io_busy) | |
178 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
179 | ||
180 | return idle_time; | |
181 | } | |
182 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
183 | ||
a9144436 | 184 | static struct cpufreq_policy *__cpufreq_cpu_get(unsigned int cpu, bool sysfs) |
1da177e4 LT |
185 | { |
186 | struct cpufreq_policy *data; | |
187 | unsigned long flags; | |
188 | ||
7a6aedfa | 189 | if (cpu >= nr_cpu_ids) |
1da177e4 LT |
190 | goto err_out; |
191 | ||
192 | /* get the cpufreq driver */ | |
1c3d85dd | 193 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 194 | |
1c3d85dd | 195 | if (!cpufreq_driver) |
1da177e4 LT |
196 | goto err_out_unlock; |
197 | ||
1c3d85dd | 198 | if (!try_module_get(cpufreq_driver->owner)) |
1da177e4 LT |
199 | goto err_out_unlock; |
200 | ||
201 | ||
202 | /* get the CPU */ | |
7a6aedfa | 203 | data = per_cpu(cpufreq_cpu_data, cpu); |
1da177e4 LT |
204 | |
205 | if (!data) | |
206 | goto err_out_put_module; | |
207 | ||
a9144436 | 208 | if (!sysfs && !kobject_get(&data->kobj)) |
1da177e4 LT |
209 | goto err_out_put_module; |
210 | ||
0d1857a1 | 211 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
212 | return data; |
213 | ||
7d5e350f | 214 | err_out_put_module: |
1c3d85dd | 215 | module_put(cpufreq_driver->owner); |
5800043b | 216 | err_out_unlock: |
1c3d85dd | 217 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
7d5e350f | 218 | err_out: |
1da177e4 LT |
219 | return NULL; |
220 | } | |
a9144436 SB |
221 | |
222 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) | |
223 | { | |
d5aaffa9 DB |
224 | if (cpufreq_disabled()) |
225 | return NULL; | |
226 | ||
a9144436 SB |
227 | return __cpufreq_cpu_get(cpu, false); |
228 | } | |
1da177e4 LT |
229 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
230 | ||
a9144436 SB |
231 | static struct cpufreq_policy *cpufreq_cpu_get_sysfs(unsigned int cpu) |
232 | { | |
233 | return __cpufreq_cpu_get(cpu, true); | |
234 | } | |
235 | ||
236 | static void __cpufreq_cpu_put(struct cpufreq_policy *data, bool sysfs) | |
237 | { | |
238 | if (!sysfs) | |
239 | kobject_put(&data->kobj); | |
1c3d85dd | 240 | module_put(cpufreq_driver->owner); |
a9144436 | 241 | } |
7d5e350f | 242 | |
1da177e4 LT |
243 | void cpufreq_cpu_put(struct cpufreq_policy *data) |
244 | { | |
d5aaffa9 DB |
245 | if (cpufreq_disabled()) |
246 | return; | |
247 | ||
a9144436 | 248 | __cpufreq_cpu_put(data, false); |
1da177e4 LT |
249 | } |
250 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
251 | ||
a9144436 SB |
252 | static void cpufreq_cpu_put_sysfs(struct cpufreq_policy *data) |
253 | { | |
254 | __cpufreq_cpu_put(data, true); | |
255 | } | |
1da177e4 | 256 | |
1da177e4 LT |
257 | /********************************************************************* |
258 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
259 | *********************************************************************/ | |
260 | ||
261 | /** | |
262 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
263 | * | |
264 | * This function alters the system "loops_per_jiffy" for the clock | |
265 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 266 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
267 | * per-CPU loops_per_jiffy value wherever possible. |
268 | */ | |
269 | #ifndef CONFIG_SMP | |
270 | static unsigned long l_p_j_ref; | |
271 | static unsigned int l_p_j_ref_freq; | |
272 | ||
858119e1 | 273 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 LT |
274 | { |
275 | if (ci->flags & CPUFREQ_CONST_LOOPS) | |
276 | return; | |
277 | ||
278 | if (!l_p_j_ref_freq) { | |
279 | l_p_j_ref = loops_per_jiffy; | |
280 | l_p_j_ref_freq = ci->old; | |
2d06d8c4 | 281 | pr_debug("saving %lu as reference value for loops_per_jiffy; " |
e08f5f5b | 282 | "freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq); |
1da177e4 | 283 | } |
d08de0c1 | 284 | if ((val == CPUFREQ_POSTCHANGE && ci->old != ci->new) || |
42d4dc3f | 285 | (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) { |
e08f5f5b GS |
286 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
287 | ci->new); | |
2d06d8c4 | 288 | pr_debug("scaling loops_per_jiffy to %lu " |
e08f5f5b | 289 | "for frequency %u kHz\n", loops_per_jiffy, ci->new); |
1da177e4 LT |
290 | } |
291 | } | |
292 | #else | |
e08f5f5b GS |
293 | static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
294 | { | |
295 | return; | |
296 | } | |
1da177e4 LT |
297 | #endif |
298 | ||
299 | ||
b43a7ffb VK |
300 | void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
301 | struct cpufreq_freqs *freqs, unsigned int state) | |
1da177e4 LT |
302 | { |
303 | BUG_ON(irqs_disabled()); | |
304 | ||
d5aaffa9 DB |
305 | if (cpufreq_disabled()) |
306 | return; | |
307 | ||
1c3d85dd | 308 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 309 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e4472cb3 | 310 | state, freqs->new); |
1da177e4 | 311 | |
1da177e4 | 312 | switch (state) { |
e4472cb3 | 313 | |
1da177e4 | 314 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 315 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
316 | * which is not equal to what the cpufreq core thinks is |
317 | * "old frequency". | |
1da177e4 | 318 | */ |
1c3d85dd | 319 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
320 | if ((policy) && (policy->cpu == freqs->cpu) && |
321 | (policy->cur) && (policy->cur != freqs->old)) { | |
2d06d8c4 | 322 | pr_debug("Warning: CPU frequency is" |
e4472cb3 DJ |
323 | " %u, cpufreq assumed %u kHz.\n", |
324 | freqs->old, policy->cur); | |
325 | freqs->old = policy->cur; | |
1da177e4 LT |
326 | } |
327 | } | |
b4dfdbb3 | 328 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 329 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
330 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
331 | break; | |
e4472cb3 | 332 | |
1da177e4 LT |
333 | case CPUFREQ_POSTCHANGE: |
334 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
2d06d8c4 | 335 | pr_debug("FREQ: %lu - CPU: %lu", (unsigned long)freqs->new, |
6f4f2723 | 336 | (unsigned long)freqs->cpu); |
25e41933 | 337 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 338 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 339 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
340 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
341 | policy->cur = freqs->new; | |
1da177e4 LT |
342 | break; |
343 | } | |
1da177e4 | 344 | } |
b43a7ffb VK |
345 | /** |
346 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
347 | * on frequency transition. | |
348 | * | |
349 | * This function calls the transition notifiers and the "adjust_jiffies" | |
350 | * function. It is called twice on all CPU frequency changes that have | |
351 | * external effects. | |
352 | */ | |
353 | void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
354 | struct cpufreq_freqs *freqs, unsigned int state) | |
355 | { | |
356 | for_each_cpu(freqs->cpu, policy->cpus) | |
357 | __cpufreq_notify_transition(policy, freqs, state); | |
358 | } | |
1da177e4 LT |
359 | EXPORT_SYMBOL_GPL(cpufreq_notify_transition); |
360 | ||
361 | ||
362 | ||
363 | /********************************************************************* | |
364 | * SYSFS INTERFACE * | |
365 | *********************************************************************/ | |
366 | ||
3bcb09a3 JF |
367 | static struct cpufreq_governor *__find_governor(const char *str_governor) |
368 | { | |
369 | struct cpufreq_governor *t; | |
370 | ||
371 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) | |
29464f28 | 372 | if (!strnicmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
373 | return t; |
374 | ||
375 | return NULL; | |
376 | } | |
377 | ||
1da177e4 LT |
378 | /** |
379 | * cpufreq_parse_governor - parse a governor string | |
380 | */ | |
905d77cd | 381 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
382 | struct cpufreq_governor **governor) |
383 | { | |
3bcb09a3 | 384 | int err = -EINVAL; |
1c3d85dd RW |
385 | |
386 | if (!cpufreq_driver) | |
3bcb09a3 JF |
387 | goto out; |
388 | ||
1c3d85dd | 389 | if (cpufreq_driver->setpolicy) { |
1da177e4 LT |
390 | if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
391 | *policy = CPUFREQ_POLICY_PERFORMANCE; | |
3bcb09a3 | 392 | err = 0; |
e08f5f5b GS |
393 | } else if (!strnicmp(str_governor, "powersave", |
394 | CPUFREQ_NAME_LEN)) { | |
1da177e4 | 395 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 396 | err = 0; |
1da177e4 | 397 | } |
1c3d85dd | 398 | } else if (cpufreq_driver->target) { |
1da177e4 | 399 | struct cpufreq_governor *t; |
3bcb09a3 | 400 | |
3fc54d37 | 401 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 JF |
402 | |
403 | t = __find_governor(str_governor); | |
404 | ||
ea714970 | 405 | if (t == NULL) { |
1a8e1463 | 406 | int ret; |
ea714970 | 407 | |
1a8e1463 KC |
408 | mutex_unlock(&cpufreq_governor_mutex); |
409 | ret = request_module("cpufreq_%s", str_governor); | |
410 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 411 | |
1a8e1463 KC |
412 | if (ret == 0) |
413 | t = __find_governor(str_governor); | |
ea714970 JF |
414 | } |
415 | ||
3bcb09a3 JF |
416 | if (t != NULL) { |
417 | *governor = t; | |
418 | err = 0; | |
1da177e4 | 419 | } |
3bcb09a3 | 420 | |
3fc54d37 | 421 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 422 | } |
29464f28 | 423 | out: |
3bcb09a3 | 424 | return err; |
1da177e4 | 425 | } |
1da177e4 LT |
426 | |
427 | ||
1da177e4 | 428 | /** |
e08f5f5b GS |
429 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
430 | * print out cpufreq information | |
1da177e4 LT |
431 | * |
432 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
433 | * "unsigned int". | |
434 | */ | |
435 | ||
32ee8c3e DJ |
436 | #define show_one(file_name, object) \ |
437 | static ssize_t show_##file_name \ | |
905d77cd | 438 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 439 | { \ |
29464f28 | 440 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
441 | } |
442 | ||
443 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
444 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 445 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
446 | show_one(scaling_min_freq, min); |
447 | show_one(scaling_max_freq, max); | |
448 | show_one(scaling_cur_freq, cur); | |
449 | ||
e08f5f5b GS |
450 | static int __cpufreq_set_policy(struct cpufreq_policy *data, |
451 | struct cpufreq_policy *policy); | |
7970e08b | 452 | |
1da177e4 LT |
453 | /** |
454 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
455 | */ | |
456 | #define store_one(file_name, object) \ | |
457 | static ssize_t store_##file_name \ | |
905d77cd | 458 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 459 | { \ |
f55c9c26 | 460 | unsigned int ret; \ |
1da177e4 LT |
461 | struct cpufreq_policy new_policy; \ |
462 | \ | |
463 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ | |
464 | if (ret) \ | |
465 | return -EINVAL; \ | |
466 | \ | |
29464f28 | 467 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
468 | if (ret != 1) \ |
469 | return -EINVAL; \ | |
470 | \ | |
7970e08b TR |
471 | ret = __cpufreq_set_policy(policy, &new_policy); \ |
472 | policy->user_policy.object = policy->object; \ | |
1da177e4 LT |
473 | \ |
474 | return ret ? ret : count; \ | |
475 | } | |
476 | ||
29464f28 DJ |
477 | store_one(scaling_min_freq, min); |
478 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
479 | |
480 | /** | |
481 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
482 | */ | |
905d77cd DJ |
483 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
484 | char *buf) | |
1da177e4 | 485 | { |
5a01f2e8 | 486 | unsigned int cur_freq = __cpufreq_get(policy->cpu); |
1da177e4 LT |
487 | if (!cur_freq) |
488 | return sprintf(buf, "<unknown>"); | |
489 | return sprintf(buf, "%u\n", cur_freq); | |
490 | } | |
491 | ||
492 | ||
493 | /** | |
494 | * show_scaling_governor - show the current policy for the specified CPU | |
495 | */ | |
905d77cd | 496 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 497 | { |
29464f28 | 498 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
499 | return sprintf(buf, "powersave\n"); |
500 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
501 | return sprintf(buf, "performance\n"); | |
502 | else if (policy->governor) | |
4b972f0b | 503 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 504 | policy->governor->name); |
1da177e4 LT |
505 | return -EINVAL; |
506 | } | |
507 | ||
508 | ||
509 | /** | |
510 | * store_scaling_governor - store policy for the specified CPU | |
511 | */ | |
905d77cd DJ |
512 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
513 | const char *buf, size_t count) | |
1da177e4 | 514 | { |
f55c9c26 | 515 | unsigned int ret; |
1da177e4 LT |
516 | char str_governor[16]; |
517 | struct cpufreq_policy new_policy; | |
518 | ||
519 | ret = cpufreq_get_policy(&new_policy, policy->cpu); | |
520 | if (ret) | |
521 | return ret; | |
522 | ||
29464f28 | 523 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
524 | if (ret != 1) |
525 | return -EINVAL; | |
526 | ||
e08f5f5b GS |
527 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
528 | &new_policy.governor)) | |
1da177e4 LT |
529 | return -EINVAL; |
530 | ||
7970e08b TR |
531 | /* Do not use cpufreq_set_policy here or the user_policy.max |
532 | will be wrongly overridden */ | |
7970e08b TR |
533 | ret = __cpufreq_set_policy(policy, &new_policy); |
534 | ||
535 | policy->user_policy.policy = policy->policy; | |
536 | policy->user_policy.governor = policy->governor; | |
7970e08b | 537 | |
e08f5f5b GS |
538 | if (ret) |
539 | return ret; | |
540 | else | |
541 | return count; | |
1da177e4 LT |
542 | } |
543 | ||
544 | /** | |
545 | * show_scaling_driver - show the cpufreq driver currently loaded | |
546 | */ | |
905d77cd | 547 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 548 | { |
1c3d85dd | 549 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
550 | } |
551 | ||
552 | /** | |
553 | * show_scaling_available_governors - show the available CPUfreq governors | |
554 | */ | |
905d77cd DJ |
555 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
556 | char *buf) | |
1da177e4 LT |
557 | { |
558 | ssize_t i = 0; | |
559 | struct cpufreq_governor *t; | |
560 | ||
1c3d85dd | 561 | if (!cpufreq_driver->target) { |
1da177e4 LT |
562 | i += sprintf(buf, "performance powersave"); |
563 | goto out; | |
564 | } | |
565 | ||
566 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { | |
29464f28 DJ |
567 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
568 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 569 | goto out; |
4b972f0b | 570 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 571 | } |
7d5e350f | 572 | out: |
1da177e4 LT |
573 | i += sprintf(&buf[i], "\n"); |
574 | return i; | |
575 | } | |
e8628dd0 | 576 | |
835481d9 | 577 | static ssize_t show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
578 | { |
579 | ssize_t i = 0; | |
580 | unsigned int cpu; | |
581 | ||
835481d9 | 582 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
583 | if (i) |
584 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
585 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
586 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 587 | break; |
1da177e4 LT |
588 | } |
589 | i += sprintf(&buf[i], "\n"); | |
590 | return i; | |
591 | } | |
592 | ||
e8628dd0 DW |
593 | /** |
594 | * show_related_cpus - show the CPUs affected by each transition even if | |
595 | * hw coordination is in use | |
596 | */ | |
597 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
598 | { | |
e8628dd0 DW |
599 | return show_cpus(policy->related_cpus, buf); |
600 | } | |
601 | ||
602 | /** | |
603 | * show_affected_cpus - show the CPUs affected by each transition | |
604 | */ | |
605 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
606 | { | |
607 | return show_cpus(policy->cpus, buf); | |
608 | } | |
609 | ||
9e76988e | 610 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 611 | const char *buf, size_t count) |
9e76988e VP |
612 | { |
613 | unsigned int freq = 0; | |
614 | unsigned int ret; | |
615 | ||
879000f9 | 616 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
617 | return -EINVAL; |
618 | ||
619 | ret = sscanf(buf, "%u", &freq); | |
620 | if (ret != 1) | |
621 | return -EINVAL; | |
622 | ||
623 | policy->governor->store_setspeed(policy, freq); | |
624 | ||
625 | return count; | |
626 | } | |
627 | ||
628 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
629 | { | |
879000f9 | 630 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
631 | return sprintf(buf, "<unsupported>\n"); |
632 | ||
633 | return policy->governor->show_setspeed(policy, buf); | |
634 | } | |
1da177e4 | 635 | |
e2f74f35 | 636 | /** |
8bf1ac72 | 637 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
638 | */ |
639 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
640 | { | |
641 | unsigned int limit; | |
642 | int ret; | |
1c3d85dd RW |
643 | if (cpufreq_driver->bios_limit) { |
644 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
645 | if (!ret) |
646 | return sprintf(buf, "%u\n", limit); | |
647 | } | |
648 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
649 | } | |
650 | ||
6dad2a29 BP |
651 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
652 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
653 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
654 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
655 | cpufreq_freq_attr_ro(scaling_available_governors); | |
656 | cpufreq_freq_attr_ro(scaling_driver); | |
657 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
658 | cpufreq_freq_attr_ro(bios_limit); | |
659 | cpufreq_freq_attr_ro(related_cpus); | |
660 | cpufreq_freq_attr_ro(affected_cpus); | |
661 | cpufreq_freq_attr_rw(scaling_min_freq); | |
662 | cpufreq_freq_attr_rw(scaling_max_freq); | |
663 | cpufreq_freq_attr_rw(scaling_governor); | |
664 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 665 | |
905d77cd | 666 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
667 | &cpuinfo_min_freq.attr, |
668 | &cpuinfo_max_freq.attr, | |
ed129784 | 669 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
670 | &scaling_min_freq.attr, |
671 | &scaling_max_freq.attr, | |
672 | &affected_cpus.attr, | |
e8628dd0 | 673 | &related_cpus.attr, |
1da177e4 LT |
674 | &scaling_governor.attr, |
675 | &scaling_driver.attr, | |
676 | &scaling_available_governors.attr, | |
9e76988e | 677 | &scaling_setspeed.attr, |
1da177e4 LT |
678 | NULL |
679 | }; | |
680 | ||
29464f28 DJ |
681 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
682 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 683 | |
29464f28 | 684 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 685 | { |
905d77cd DJ |
686 | struct cpufreq_policy *policy = to_policy(kobj); |
687 | struct freq_attr *fattr = to_attr(attr); | |
0db4a8a9 | 688 | ssize_t ret = -EINVAL; |
a9144436 | 689 | policy = cpufreq_cpu_get_sysfs(policy->cpu); |
1da177e4 | 690 | if (!policy) |
0db4a8a9 | 691 | goto no_policy; |
5a01f2e8 VP |
692 | |
693 | if (lock_policy_rwsem_read(policy->cpu) < 0) | |
0db4a8a9 | 694 | goto fail; |
5a01f2e8 | 695 | |
e08f5f5b GS |
696 | if (fattr->show) |
697 | ret = fattr->show(policy, buf); | |
698 | else | |
699 | ret = -EIO; | |
700 | ||
5a01f2e8 | 701 | unlock_policy_rwsem_read(policy->cpu); |
0db4a8a9 | 702 | fail: |
a9144436 | 703 | cpufreq_cpu_put_sysfs(policy); |
0db4a8a9 | 704 | no_policy: |
1da177e4 LT |
705 | return ret; |
706 | } | |
707 | ||
905d77cd DJ |
708 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
709 | const char *buf, size_t count) | |
1da177e4 | 710 | { |
905d77cd DJ |
711 | struct cpufreq_policy *policy = to_policy(kobj); |
712 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 713 | ssize_t ret = -EINVAL; |
a9144436 | 714 | policy = cpufreq_cpu_get_sysfs(policy->cpu); |
1da177e4 | 715 | if (!policy) |
a07530b4 | 716 | goto no_policy; |
5a01f2e8 VP |
717 | |
718 | if (lock_policy_rwsem_write(policy->cpu) < 0) | |
a07530b4 | 719 | goto fail; |
5a01f2e8 | 720 | |
e08f5f5b GS |
721 | if (fattr->store) |
722 | ret = fattr->store(policy, buf, count); | |
723 | else | |
724 | ret = -EIO; | |
725 | ||
5a01f2e8 | 726 | unlock_policy_rwsem_write(policy->cpu); |
a07530b4 | 727 | fail: |
a9144436 | 728 | cpufreq_cpu_put_sysfs(policy); |
a07530b4 | 729 | no_policy: |
1da177e4 LT |
730 | return ret; |
731 | } | |
732 | ||
905d77cd | 733 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 734 | { |
905d77cd | 735 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 736 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
737 | complete(&policy->kobj_unregister); |
738 | } | |
739 | ||
52cf25d0 | 740 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
741 | .show = show, |
742 | .store = store, | |
743 | }; | |
744 | ||
745 | static struct kobj_type ktype_cpufreq = { | |
746 | .sysfs_ops = &sysfs_ops, | |
747 | .default_attrs = default_attrs, | |
748 | .release = cpufreq_sysfs_release, | |
749 | }; | |
750 | ||
2361be23 VK |
751 | struct kobject *cpufreq_global_kobject; |
752 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
753 | ||
754 | static int cpufreq_global_kobject_usage; | |
755 | ||
756 | int cpufreq_get_global_kobject(void) | |
757 | { | |
758 | if (!cpufreq_global_kobject_usage++) | |
759 | return kobject_add(cpufreq_global_kobject, | |
760 | &cpu_subsys.dev_root->kobj, "%s", "cpufreq"); | |
761 | ||
762 | return 0; | |
763 | } | |
764 | EXPORT_SYMBOL(cpufreq_get_global_kobject); | |
765 | ||
766 | void cpufreq_put_global_kobject(void) | |
767 | { | |
768 | if (!--cpufreq_global_kobject_usage) | |
769 | kobject_del(cpufreq_global_kobject); | |
770 | } | |
771 | EXPORT_SYMBOL(cpufreq_put_global_kobject); | |
772 | ||
773 | int cpufreq_sysfs_create_file(const struct attribute *attr) | |
774 | { | |
775 | int ret = cpufreq_get_global_kobject(); | |
776 | ||
777 | if (!ret) { | |
778 | ret = sysfs_create_file(cpufreq_global_kobject, attr); | |
779 | if (ret) | |
780 | cpufreq_put_global_kobject(); | |
781 | } | |
782 | ||
783 | return ret; | |
784 | } | |
785 | EXPORT_SYMBOL(cpufreq_sysfs_create_file); | |
786 | ||
787 | void cpufreq_sysfs_remove_file(const struct attribute *attr) | |
788 | { | |
789 | sysfs_remove_file(cpufreq_global_kobject, attr); | |
790 | cpufreq_put_global_kobject(); | |
791 | } | |
792 | EXPORT_SYMBOL(cpufreq_sysfs_remove_file); | |
793 | ||
19d6f7ec | 794 | /* symlink affected CPUs */ |
cf3289d0 AC |
795 | static int cpufreq_add_dev_symlink(unsigned int cpu, |
796 | struct cpufreq_policy *policy) | |
19d6f7ec DJ |
797 | { |
798 | unsigned int j; | |
799 | int ret = 0; | |
800 | ||
801 | for_each_cpu(j, policy->cpus) { | |
802 | struct cpufreq_policy *managed_policy; | |
8a25a2fd | 803 | struct device *cpu_dev; |
19d6f7ec DJ |
804 | |
805 | if (j == cpu) | |
806 | continue; | |
19d6f7ec | 807 | |
2d06d8c4 | 808 | pr_debug("CPU %u already managed, adding link\n", j); |
19d6f7ec | 809 | managed_policy = cpufreq_cpu_get(cpu); |
8a25a2fd KS |
810 | cpu_dev = get_cpu_device(j); |
811 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
19d6f7ec DJ |
812 | "cpufreq"); |
813 | if (ret) { | |
814 | cpufreq_cpu_put(managed_policy); | |
815 | return ret; | |
816 | } | |
817 | } | |
818 | return ret; | |
819 | } | |
820 | ||
cf3289d0 AC |
821 | static int cpufreq_add_dev_interface(unsigned int cpu, |
822 | struct cpufreq_policy *policy, | |
8a25a2fd | 823 | struct device *dev) |
909a694e | 824 | { |
ecf7e461 | 825 | struct cpufreq_policy new_policy; |
909a694e DJ |
826 | struct freq_attr **drv_attr; |
827 | unsigned long flags; | |
828 | int ret = 0; | |
829 | unsigned int j; | |
830 | ||
831 | /* prepare interface data */ | |
832 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, | |
8a25a2fd | 833 | &dev->kobj, "cpufreq"); |
909a694e DJ |
834 | if (ret) |
835 | return ret; | |
836 | ||
837 | /* set up files for this cpu device */ | |
1c3d85dd | 838 | drv_attr = cpufreq_driver->attr; |
909a694e DJ |
839 | while ((drv_attr) && (*drv_attr)) { |
840 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); | |
841 | if (ret) | |
1c3d85dd | 842 | goto err_out_kobj_put; |
909a694e DJ |
843 | drv_attr++; |
844 | } | |
1c3d85dd | 845 | if (cpufreq_driver->get) { |
909a694e DJ |
846 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
847 | if (ret) | |
1c3d85dd | 848 | goto err_out_kobj_put; |
909a694e | 849 | } |
1c3d85dd | 850 | if (cpufreq_driver->target) { |
909a694e DJ |
851 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); |
852 | if (ret) | |
1c3d85dd | 853 | goto err_out_kobj_put; |
909a694e | 854 | } |
1c3d85dd | 855 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
856 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
857 | if (ret) | |
1c3d85dd | 858 | goto err_out_kobj_put; |
e2f74f35 | 859 | } |
909a694e | 860 | |
0d1857a1 | 861 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
909a694e | 862 | for_each_cpu(j, policy->cpus) { |
909a694e | 863 | per_cpu(cpufreq_cpu_data, j) = policy; |
f1625066 | 864 | per_cpu(cpufreq_policy_cpu, j) = policy->cpu; |
909a694e | 865 | } |
0d1857a1 | 866 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
909a694e DJ |
867 | |
868 | ret = cpufreq_add_dev_symlink(cpu, policy); | |
ecf7e461 DJ |
869 | if (ret) |
870 | goto err_out_kobj_put; | |
871 | ||
872 | memcpy(&new_policy, policy, sizeof(struct cpufreq_policy)); | |
873 | /* assure that the starting sequence is run in __cpufreq_set_policy */ | |
874 | policy->governor = NULL; | |
875 | ||
876 | /* set default policy */ | |
877 | ret = __cpufreq_set_policy(policy, &new_policy); | |
878 | policy->user_policy.policy = policy->policy; | |
879 | policy->user_policy.governor = policy->governor; | |
880 | ||
881 | if (ret) { | |
2d06d8c4 | 882 | pr_debug("setting policy failed\n"); |
1c3d85dd RW |
883 | if (cpufreq_driver->exit) |
884 | cpufreq_driver->exit(policy); | |
ecf7e461 | 885 | } |
909a694e DJ |
886 | return ret; |
887 | ||
888 | err_out_kobj_put: | |
889 | kobject_put(&policy->kobj); | |
890 | wait_for_completion(&policy->kobj_unregister); | |
891 | return ret; | |
892 | } | |
893 | ||
fcf80582 VK |
894 | #ifdef CONFIG_HOTPLUG_CPU |
895 | static int cpufreq_add_policy_cpu(unsigned int cpu, unsigned int sibling, | |
896 | struct device *dev) | |
897 | { | |
898 | struct cpufreq_policy *policy; | |
1c3d85dd | 899 | int ret = 0, has_target = !!cpufreq_driver->target; |
fcf80582 VK |
900 | unsigned long flags; |
901 | ||
902 | policy = cpufreq_cpu_get(sibling); | |
903 | WARN_ON(!policy); | |
904 | ||
820c6ca2 VK |
905 | if (has_target) |
906 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
fcf80582 | 907 | |
2eaa3e2d VK |
908 | lock_policy_rwsem_write(sibling); |
909 | ||
0d1857a1 | 910 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 911 | |
fcf80582 | 912 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 913 | per_cpu(cpufreq_policy_cpu, cpu) = policy->cpu; |
fcf80582 | 914 | per_cpu(cpufreq_cpu_data, cpu) = policy; |
0d1857a1 | 915 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fcf80582 | 916 | |
2eaa3e2d VK |
917 | unlock_policy_rwsem_write(sibling); |
918 | ||
820c6ca2 VK |
919 | if (has_target) { |
920 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
921 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
922 | } | |
fcf80582 | 923 | |
fcf80582 VK |
924 | ret = sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); |
925 | if (ret) { | |
926 | cpufreq_cpu_put(policy); | |
927 | return ret; | |
928 | } | |
929 | ||
930 | return 0; | |
931 | } | |
932 | #endif | |
1da177e4 LT |
933 | |
934 | /** | |
935 | * cpufreq_add_dev - add a CPU device | |
936 | * | |
32ee8c3e | 937 | * Adds the cpufreq interface for a CPU device. |
3f4a782b MD |
938 | * |
939 | * The Oracle says: try running cpufreq registration/unregistration concurrently | |
940 | * with with cpu hotplugging and all hell will break loose. Tried to clean this | |
941 | * mess up, but more thorough testing is needed. - Mathieu | |
1da177e4 | 942 | */ |
8a25a2fd | 943 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) |
1da177e4 | 944 | { |
fcf80582 | 945 | unsigned int j, cpu = dev->id; |
65922465 | 946 | int ret = -ENOMEM; |
1da177e4 | 947 | struct cpufreq_policy *policy; |
1da177e4 | 948 | unsigned long flags; |
90e41bac | 949 | #ifdef CONFIG_HOTPLUG_CPU |
fcf80582 | 950 | struct cpufreq_governor *gov; |
90e41bac PB |
951 | int sibling; |
952 | #endif | |
1da177e4 | 953 | |
c32b6b8e AR |
954 | if (cpu_is_offline(cpu)) |
955 | return 0; | |
956 | ||
2d06d8c4 | 957 | pr_debug("adding CPU %u\n", cpu); |
1da177e4 LT |
958 | |
959 | #ifdef CONFIG_SMP | |
960 | /* check whether a different CPU already registered this | |
961 | * CPU because it is in the same boat. */ | |
962 | policy = cpufreq_cpu_get(cpu); | |
963 | if (unlikely(policy)) { | |
8ff69732 | 964 | cpufreq_cpu_put(policy); |
1da177e4 LT |
965 | return 0; |
966 | } | |
fcf80582 VK |
967 | |
968 | #ifdef CONFIG_HOTPLUG_CPU | |
969 | /* Check if this cpu was hot-unplugged earlier and has siblings */ | |
0d1857a1 | 970 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
fcf80582 VK |
971 | for_each_online_cpu(sibling) { |
972 | struct cpufreq_policy *cp = per_cpu(cpufreq_cpu_data, sibling); | |
2eaa3e2d | 973 | if (cp && cpumask_test_cpu(cpu, cp->related_cpus)) { |
0d1857a1 | 974 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fcf80582 | 975 | return cpufreq_add_policy_cpu(cpu, sibling, dev); |
2eaa3e2d | 976 | } |
fcf80582 | 977 | } |
0d1857a1 | 978 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fcf80582 | 979 | #endif |
1da177e4 LT |
980 | #endif |
981 | ||
1c3d85dd | 982 | if (!try_module_get(cpufreq_driver->owner)) { |
1da177e4 LT |
983 | ret = -EINVAL; |
984 | goto module_out; | |
985 | } | |
986 | ||
e98df50c | 987 | policy = kzalloc(sizeof(struct cpufreq_policy), GFP_KERNEL); |
059019a3 | 988 | if (!policy) |
1da177e4 | 989 | goto nomem_out; |
059019a3 DJ |
990 | |
991 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
3f4a782b | 992 | goto err_free_policy; |
059019a3 DJ |
993 | |
994 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
3f4a782b | 995 | goto err_free_cpumask; |
1da177e4 LT |
996 | |
997 | policy->cpu = cpu; | |
65922465 | 998 | policy->governor = CPUFREQ_DEFAULT_GOVERNOR; |
835481d9 | 999 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1000 | |
5a01f2e8 | 1001 | /* Initially set CPU itself as the policy_cpu */ |
f1625066 | 1002 | per_cpu(cpufreq_policy_cpu, cpu) = cpu; |
5a01f2e8 | 1003 | |
1da177e4 | 1004 | init_completion(&policy->kobj_unregister); |
65f27f38 | 1005 | INIT_WORK(&policy->update, handle_update); |
1da177e4 LT |
1006 | |
1007 | /* call driver. From then on the cpufreq must be able | |
1008 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1009 | */ | |
1c3d85dd | 1010 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1011 | if (ret) { |
2d06d8c4 | 1012 | pr_debug("initialization failed\n"); |
2eaa3e2d | 1013 | goto err_set_policy_cpu; |
1da177e4 | 1014 | } |
643ae6e8 | 1015 | |
fcf80582 VK |
1016 | /* related cpus should atleast have policy->cpus */ |
1017 | cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); | |
1018 | ||
643ae6e8 VK |
1019 | /* |
1020 | * affected cpus must always be the one, which are online. We aren't | |
1021 | * managing offline cpus here. | |
1022 | */ | |
1023 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1024 | ||
187d9f4e MC |
1025 | policy->user_policy.min = policy->min; |
1026 | policy->user_policy.max = policy->max; | |
1da177e4 | 1027 | |
a1531acd TR |
1028 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1029 | CPUFREQ_START, policy); | |
1030 | ||
fcf80582 VK |
1031 | #ifdef CONFIG_HOTPLUG_CPU |
1032 | gov = __find_governor(per_cpu(cpufreq_cpu_governor, cpu)); | |
1033 | if (gov) { | |
1034 | policy->governor = gov; | |
1035 | pr_debug("Restoring governor %s for cpu %d\n", | |
1036 | policy->governor->name, cpu); | |
4bfa042c | 1037 | } |
fcf80582 | 1038 | #endif |
1da177e4 | 1039 | |
8a25a2fd | 1040 | ret = cpufreq_add_dev_interface(cpu, policy, dev); |
19d6f7ec DJ |
1041 | if (ret) |
1042 | goto err_out_unregister; | |
8ff69732 | 1043 | |
038c5b3e | 1044 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
1c3d85dd | 1045 | module_put(cpufreq_driver->owner); |
2d06d8c4 | 1046 | pr_debug("initialization complete\n"); |
87c32271 | 1047 | |
1da177e4 LT |
1048 | return 0; |
1049 | ||
1da177e4 | 1050 | err_out_unregister: |
0d1857a1 | 1051 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
835481d9 | 1052 | for_each_cpu(j, policy->cpus) |
7a6aedfa | 1053 | per_cpu(cpufreq_cpu_data, j) = NULL; |
0d1857a1 | 1054 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1055 | |
c10997f6 | 1056 | kobject_put(&policy->kobj); |
1da177e4 LT |
1057 | wait_for_completion(&policy->kobj_unregister); |
1058 | ||
2eaa3e2d VK |
1059 | err_set_policy_cpu: |
1060 | per_cpu(cpufreq_policy_cpu, cpu) = -1; | |
cad70a6a | 1061 | free_cpumask_var(policy->related_cpus); |
3f4a782b MD |
1062 | err_free_cpumask: |
1063 | free_cpumask_var(policy->cpus); | |
1064 | err_free_policy: | |
1da177e4 | 1065 | kfree(policy); |
1da177e4 | 1066 | nomem_out: |
1c3d85dd | 1067 | module_put(cpufreq_driver->owner); |
c32b6b8e | 1068 | module_out: |
1da177e4 LT |
1069 | return ret; |
1070 | } | |
1071 | ||
b8eed8af VK |
1072 | static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
1073 | { | |
1074 | int j; | |
1075 | ||
1076 | policy->last_cpu = policy->cpu; | |
1077 | policy->cpu = cpu; | |
1078 | ||
3361b7b1 | 1079 | for_each_cpu(j, policy->cpus) |
b8eed8af | 1080 | per_cpu(cpufreq_policy_cpu, j) = cpu; |
b8eed8af VK |
1081 | |
1082 | #ifdef CONFIG_CPU_FREQ_TABLE | |
1083 | cpufreq_frequency_table_update_policy_cpu(policy); | |
1084 | #endif | |
1085 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1086 | CPUFREQ_UPDATE_POLICY_CPU, policy); | |
1087 | } | |
1da177e4 LT |
1088 | |
1089 | /** | |
5a01f2e8 | 1090 | * __cpufreq_remove_dev - remove a CPU device |
1da177e4 LT |
1091 | * |
1092 | * Removes the cpufreq interface for a CPU device. | |
5a01f2e8 VP |
1093 | * Caller should already have policy_rwsem in write mode for this CPU. |
1094 | * This routine frees the rwsem before returning. | |
1da177e4 | 1095 | */ |
8a25a2fd | 1096 | static int __cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
1da177e4 | 1097 | { |
b8eed8af | 1098 | unsigned int cpu = dev->id, ret, cpus; |
1da177e4 LT |
1099 | unsigned long flags; |
1100 | struct cpufreq_policy *data; | |
499bca9b AW |
1101 | struct kobject *kobj; |
1102 | struct completion *cmp; | |
8a25a2fd | 1103 | struct device *cpu_dev; |
1da177e4 | 1104 | |
b8eed8af | 1105 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1106 | |
0d1857a1 | 1107 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 1108 | |
7a6aedfa | 1109 | data = per_cpu(cpufreq_cpu_data, cpu); |
2eaa3e2d VK |
1110 | per_cpu(cpufreq_cpu_data, cpu) = NULL; |
1111 | ||
0d1857a1 | 1112 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
1113 | |
1114 | if (!data) { | |
b8eed8af | 1115 | pr_debug("%s: No cpu_data found\n", __func__); |
1da177e4 LT |
1116 | return -EINVAL; |
1117 | } | |
1da177e4 | 1118 | |
1c3d85dd | 1119 | if (cpufreq_driver->target) |
f6a7409c | 1120 | __cpufreq_governor(data, CPUFREQ_GOV_STOP); |
1da177e4 | 1121 | |
084f3493 | 1122 | #ifdef CONFIG_HOTPLUG_CPU |
1c3d85dd | 1123 | if (!cpufreq_driver->setpolicy) |
fa69e33f DB |
1124 | strncpy(per_cpu(cpufreq_cpu_governor, cpu), |
1125 | data->governor->name, CPUFREQ_NAME_LEN); | |
1da177e4 LT |
1126 | #endif |
1127 | ||
2eaa3e2d | 1128 | WARN_ON(lock_policy_rwsem_write(cpu)); |
b8eed8af | 1129 | cpus = cpumask_weight(data->cpus); |
e4969eba VK |
1130 | |
1131 | if (cpus > 1) | |
1132 | cpumask_clear_cpu(cpu, data->cpus); | |
2eaa3e2d | 1133 | unlock_policy_rwsem_write(cpu); |
084f3493 | 1134 | |
73bf0fc2 VK |
1135 | if (cpu != data->cpu) { |
1136 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
1137 | } else if (cpus > 1) { | |
b8eed8af VK |
1138 | /* first sibling now owns the new sysfs dir */ |
1139 | cpu_dev = get_cpu_device(cpumask_first(data->cpus)); | |
1140 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); | |
1141 | ret = kobject_move(&data->kobj, &cpu_dev->kobj); | |
1142 | if (ret) { | |
1143 | pr_err("%s: Failed to move kobj: %d", __func__, ret); | |
084f3493 | 1144 | |
2eaa3e2d | 1145 | WARN_ON(lock_policy_rwsem_write(cpu)); |
b8eed8af | 1146 | cpumask_set_cpu(cpu, data->cpus); |
1da177e4 | 1147 | |
0d1857a1 | 1148 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 1149 | per_cpu(cpufreq_cpu_data, cpu) = data; |
0d1857a1 | 1150 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1151 | |
499bca9b | 1152 | unlock_policy_rwsem_write(cpu); |
1da177e4 | 1153 | |
2eaa3e2d VK |
1154 | ret = sysfs_create_link(&cpu_dev->kobj, &data->kobj, |
1155 | "cpufreq"); | |
b8eed8af | 1156 | return -EINVAL; |
1da177e4 | 1157 | } |
5a01f2e8 | 1158 | |
2eaa3e2d | 1159 | WARN_ON(lock_policy_rwsem_write(cpu)); |
b8eed8af | 1160 | update_policy_cpu(data, cpu_dev->id); |
2eaa3e2d | 1161 | unlock_policy_rwsem_write(cpu); |
b8eed8af VK |
1162 | pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n", |
1163 | __func__, cpu_dev->id, cpu); | |
1da177e4 | 1164 | } |
1da177e4 | 1165 | |
d96038e0 VK |
1166 | if ((cpus == 1) && (cpufreq_driver->target)) |
1167 | __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); | |
1168 | ||
b8eed8af VK |
1169 | pr_debug("%s: removing link, cpu: %d\n", __func__, cpu); |
1170 | cpufreq_cpu_put(data); | |
1da177e4 | 1171 | |
b8eed8af VK |
1172 | /* If cpu is last user of policy, free policy */ |
1173 | if (cpus == 1) { | |
2eaa3e2d | 1174 | lock_policy_rwsem_read(cpu); |
b8eed8af VK |
1175 | kobj = &data->kobj; |
1176 | cmp = &data->kobj_unregister; | |
2eaa3e2d | 1177 | unlock_policy_rwsem_read(cpu); |
b8eed8af | 1178 | kobject_put(kobj); |
7d26e2d5 | 1179 | |
b8eed8af VK |
1180 | /* we need to make sure that the underlying kobj is actually |
1181 | * not referenced anymore by anybody before we proceed with | |
1182 | * unloading. | |
1183 | */ | |
1184 | pr_debug("waiting for dropping of refcount\n"); | |
1185 | wait_for_completion(cmp); | |
1186 | pr_debug("wait complete\n"); | |
7d26e2d5 | 1187 | |
1c3d85dd RW |
1188 | if (cpufreq_driver->exit) |
1189 | cpufreq_driver->exit(data); | |
27ecddc2 | 1190 | |
b8eed8af VK |
1191 | free_cpumask_var(data->related_cpus); |
1192 | free_cpumask_var(data->cpus); | |
1193 | kfree(data); | |
1c3d85dd | 1194 | } else if (cpufreq_driver->target) { |
b8eed8af VK |
1195 | __cpufreq_governor(data, CPUFREQ_GOV_START); |
1196 | __cpufreq_governor(data, CPUFREQ_GOV_LIMITS); | |
27ecddc2 | 1197 | } |
1da177e4 | 1198 | |
2eaa3e2d | 1199 | per_cpu(cpufreq_policy_cpu, cpu) = -1; |
1da177e4 LT |
1200 | return 0; |
1201 | } | |
1202 | ||
1203 | ||
8a25a2fd | 1204 | static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1205 | { |
8a25a2fd | 1206 | unsigned int cpu = dev->id; |
5a01f2e8 | 1207 | int retval; |
ec28297a VP |
1208 | |
1209 | if (cpu_is_offline(cpu)) | |
1210 | return 0; | |
1211 | ||
8a25a2fd | 1212 | retval = __cpufreq_remove_dev(dev, sif); |
5a01f2e8 VP |
1213 | return retval; |
1214 | } | |
1215 | ||
1216 | ||
65f27f38 | 1217 | static void handle_update(struct work_struct *work) |
1da177e4 | 1218 | { |
65f27f38 DH |
1219 | struct cpufreq_policy *policy = |
1220 | container_of(work, struct cpufreq_policy, update); | |
1221 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1222 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1223 | cpufreq_update_policy(cpu); |
1224 | } | |
1225 | ||
1226 | /** | |
1227 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're in deep trouble. | |
1228 | * @cpu: cpu number | |
1229 | * @old_freq: CPU frequency the kernel thinks the CPU runs at | |
1230 | * @new_freq: CPU frequency the CPU actually runs at | |
1231 | * | |
29464f28 DJ |
1232 | * We adjust to current frequency first, and need to clean up later. |
1233 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1234 | */ |
e08f5f5b GS |
1235 | static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, |
1236 | unsigned int new_freq) | |
1da177e4 | 1237 | { |
b43a7ffb | 1238 | struct cpufreq_policy *policy; |
1da177e4 | 1239 | struct cpufreq_freqs freqs; |
b43a7ffb VK |
1240 | unsigned long flags; |
1241 | ||
1da177e4 | 1242 | |
2d06d8c4 | 1243 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing " |
1da177e4 LT |
1244 | "core thinks of %u, is %u kHz.\n", old_freq, new_freq); |
1245 | ||
1da177e4 LT |
1246 | freqs.old = old_freq; |
1247 | freqs.new = new_freq; | |
b43a7ffb VK |
1248 | |
1249 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1250 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1251 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1252 | ||
1253 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); | |
1254 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); | |
1da177e4 LT |
1255 | } |
1256 | ||
1257 | ||
32ee8c3e | 1258 | /** |
4ab70df4 | 1259 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1260 | * @cpu: CPU number |
1261 | * | |
1262 | * This is the last known freq, without actually getting it from the driver. | |
1263 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1264 | */ | |
1265 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1266 | { | |
9e21ba8b | 1267 | struct cpufreq_policy *policy; |
e08f5f5b | 1268 | unsigned int ret_freq = 0; |
95235ca2 | 1269 | |
1c3d85dd RW |
1270 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1271 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1272 | |
1273 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1274 | if (policy) { |
e08f5f5b | 1275 | ret_freq = policy->cur; |
95235ca2 VP |
1276 | cpufreq_cpu_put(policy); |
1277 | } | |
1278 | ||
4d34a67d | 1279 | return ret_freq; |
95235ca2 VP |
1280 | } |
1281 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1282 | ||
3d737108 JB |
1283 | /** |
1284 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1285 | * @cpu: CPU number | |
1286 | * | |
1287 | * Just return the max possible frequency for a given CPU. | |
1288 | */ | |
1289 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1290 | { | |
1291 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1292 | unsigned int ret_freq = 0; | |
1293 | ||
1294 | if (policy) { | |
1295 | ret_freq = policy->max; | |
1296 | cpufreq_cpu_put(policy); | |
1297 | } | |
1298 | ||
1299 | return ret_freq; | |
1300 | } | |
1301 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1302 | ||
95235ca2 | 1303 | |
5a01f2e8 | 1304 | static unsigned int __cpufreq_get(unsigned int cpu) |
1da177e4 | 1305 | { |
7a6aedfa | 1306 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
e08f5f5b | 1307 | unsigned int ret_freq = 0; |
5800043b | 1308 | |
1c3d85dd | 1309 | if (!cpufreq_driver->get) |
4d34a67d | 1310 | return ret_freq; |
1da177e4 | 1311 | |
1c3d85dd | 1312 | ret_freq = cpufreq_driver->get(cpu); |
1da177e4 | 1313 | |
e08f5f5b | 1314 | if (ret_freq && policy->cur && |
1c3d85dd | 1315 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1316 | /* verify no discrepancy between actual and |
1317 | saved value exists */ | |
1318 | if (unlikely(ret_freq != policy->cur)) { | |
1319 | cpufreq_out_of_sync(cpu, policy->cur, ret_freq); | |
1da177e4 LT |
1320 | schedule_work(&policy->update); |
1321 | } | |
1322 | } | |
1323 | ||
4d34a67d | 1324 | return ret_freq; |
5a01f2e8 | 1325 | } |
1da177e4 | 1326 | |
5a01f2e8 VP |
1327 | /** |
1328 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1329 | * @cpu: CPU number | |
1330 | * | |
1331 | * Get the CPU current (static) CPU frequency | |
1332 | */ | |
1333 | unsigned int cpufreq_get(unsigned int cpu) | |
1334 | { | |
1335 | unsigned int ret_freq = 0; | |
1336 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1337 | ||
1338 | if (!policy) | |
1339 | goto out; | |
1340 | ||
1341 | if (unlikely(lock_policy_rwsem_read(cpu))) | |
1342 | goto out_policy; | |
1343 | ||
1344 | ret_freq = __cpufreq_get(cpu); | |
1345 | ||
1346 | unlock_policy_rwsem_read(cpu); | |
1da177e4 | 1347 | |
5a01f2e8 VP |
1348 | out_policy: |
1349 | cpufreq_cpu_put(policy); | |
1350 | out: | |
4d34a67d | 1351 | return ret_freq; |
1da177e4 LT |
1352 | } |
1353 | EXPORT_SYMBOL(cpufreq_get); | |
1354 | ||
8a25a2fd KS |
1355 | static struct subsys_interface cpufreq_interface = { |
1356 | .name = "cpufreq", | |
1357 | .subsys = &cpu_subsys, | |
1358 | .add_dev = cpufreq_add_dev, | |
1359 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1360 | }; |
1361 | ||
1da177e4 | 1362 | |
42d4dc3f | 1363 | /** |
e00e56df RW |
1364 | * cpufreq_bp_suspend - Prepare the boot CPU for system suspend. |
1365 | * | |
1366 | * This function is only executed for the boot processor. The other CPUs | |
1367 | * have been put offline by means of CPU hotplug. | |
42d4dc3f | 1368 | */ |
e00e56df | 1369 | static int cpufreq_bp_suspend(void) |
42d4dc3f | 1370 | { |
e08f5f5b | 1371 | int ret = 0; |
4bc5d341 | 1372 | |
e00e56df | 1373 | int cpu = smp_processor_id(); |
42d4dc3f BH |
1374 | struct cpufreq_policy *cpu_policy; |
1375 | ||
2d06d8c4 | 1376 | pr_debug("suspending cpu %u\n", cpu); |
42d4dc3f | 1377 | |
e00e56df | 1378 | /* If there's no policy for the boot CPU, we have nothing to do. */ |
42d4dc3f BH |
1379 | cpu_policy = cpufreq_cpu_get(cpu); |
1380 | if (!cpu_policy) | |
e00e56df | 1381 | return 0; |
42d4dc3f | 1382 | |
1c3d85dd RW |
1383 | if (cpufreq_driver->suspend) { |
1384 | ret = cpufreq_driver->suspend(cpu_policy); | |
ce6c3997 | 1385 | if (ret) |
42d4dc3f BH |
1386 | printk(KERN_ERR "cpufreq: suspend failed in ->suspend " |
1387 | "step on CPU %u\n", cpu_policy->cpu); | |
42d4dc3f BH |
1388 | } |
1389 | ||
42d4dc3f | 1390 | cpufreq_cpu_put(cpu_policy); |
c9060494 | 1391 | return ret; |
42d4dc3f BH |
1392 | } |
1393 | ||
1da177e4 | 1394 | /** |
e00e56df | 1395 | * cpufreq_bp_resume - Restore proper frequency handling of the boot CPU. |
1da177e4 LT |
1396 | * |
1397 | * 1.) resume CPUfreq hardware support (cpufreq_driver->resume()) | |
ce6c3997 DB |
1398 | * 2.) schedule call cpufreq_update_policy() ASAP as interrupts are |
1399 | * restored. It will verify that the current freq is in sync with | |
1400 | * what we believe it to be. This is a bit later than when it | |
1401 | * should be, but nonethteless it's better than calling | |
1402 | * cpufreq_driver->get() here which might re-enable interrupts... | |
e00e56df RW |
1403 | * |
1404 | * This function is only executed for the boot CPU. The other CPUs have not | |
1405 | * been turned on yet. | |
1da177e4 | 1406 | */ |
e00e56df | 1407 | static void cpufreq_bp_resume(void) |
1da177e4 | 1408 | { |
e08f5f5b | 1409 | int ret = 0; |
4bc5d341 | 1410 | |
e00e56df | 1411 | int cpu = smp_processor_id(); |
1da177e4 LT |
1412 | struct cpufreq_policy *cpu_policy; |
1413 | ||
2d06d8c4 | 1414 | pr_debug("resuming cpu %u\n", cpu); |
1da177e4 | 1415 | |
e00e56df | 1416 | /* If there's no policy for the boot CPU, we have nothing to do. */ |
1da177e4 LT |
1417 | cpu_policy = cpufreq_cpu_get(cpu); |
1418 | if (!cpu_policy) | |
e00e56df | 1419 | return; |
1da177e4 | 1420 | |
1c3d85dd RW |
1421 | if (cpufreq_driver->resume) { |
1422 | ret = cpufreq_driver->resume(cpu_policy); | |
1da177e4 LT |
1423 | if (ret) { |
1424 | printk(KERN_ERR "cpufreq: resume failed in ->resume " | |
1425 | "step on CPU %u\n", cpu_policy->cpu); | |
c9060494 | 1426 | goto fail; |
1da177e4 LT |
1427 | } |
1428 | } | |
1429 | ||
1da177e4 | 1430 | schedule_work(&cpu_policy->update); |
ce6c3997 | 1431 | |
c9060494 | 1432 | fail: |
1da177e4 | 1433 | cpufreq_cpu_put(cpu_policy); |
1da177e4 LT |
1434 | } |
1435 | ||
e00e56df RW |
1436 | static struct syscore_ops cpufreq_syscore_ops = { |
1437 | .suspend = cpufreq_bp_suspend, | |
1438 | .resume = cpufreq_bp_resume, | |
1da177e4 LT |
1439 | }; |
1440 | ||
9d95046e BP |
1441 | /** |
1442 | * cpufreq_get_current_driver - return current driver's name | |
1443 | * | |
1444 | * Return the name string of the currently loaded cpufreq driver | |
1445 | * or NULL, if none. | |
1446 | */ | |
1447 | const char *cpufreq_get_current_driver(void) | |
1448 | { | |
1c3d85dd RW |
1449 | if (cpufreq_driver) |
1450 | return cpufreq_driver->name; | |
1451 | ||
1452 | return NULL; | |
9d95046e BP |
1453 | } |
1454 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 LT |
1455 | |
1456 | /********************************************************************* | |
1457 | * NOTIFIER LISTS INTERFACE * | |
1458 | *********************************************************************/ | |
1459 | ||
1460 | /** | |
1461 | * cpufreq_register_notifier - register a driver with cpufreq | |
1462 | * @nb: notifier function to register | |
1463 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1464 | * | |
32ee8c3e | 1465 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1466 | * are notified about clock rate changes (once before and once after |
1467 | * the transition), or a list of drivers that are notified about | |
1468 | * changes in cpufreq policy. | |
1469 | * | |
1470 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1471 | * blocking_notifier_chain_register. |
1da177e4 LT |
1472 | */ |
1473 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1474 | { | |
1475 | int ret; | |
1476 | ||
d5aaffa9 DB |
1477 | if (cpufreq_disabled()) |
1478 | return -EINVAL; | |
1479 | ||
74212ca4 CEB |
1480 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1481 | ||
1da177e4 LT |
1482 | switch (list) { |
1483 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1484 | ret = srcu_notifier_chain_register( |
e041c683 | 1485 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1486 | break; |
1487 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1488 | ret = blocking_notifier_chain_register( |
1489 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1490 | break; |
1491 | default: | |
1492 | ret = -EINVAL; | |
1493 | } | |
1da177e4 LT |
1494 | |
1495 | return ret; | |
1496 | } | |
1497 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1498 | ||
1499 | ||
1500 | /** | |
1501 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1502 | * @nb: notifier block to be unregistered | |
1503 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1504 | * | |
1505 | * Remove a driver from the CPU frequency notifier list. | |
1506 | * | |
1507 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1508 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1509 | */ |
1510 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1511 | { | |
1512 | int ret; | |
1513 | ||
d5aaffa9 DB |
1514 | if (cpufreq_disabled()) |
1515 | return -EINVAL; | |
1516 | ||
1da177e4 LT |
1517 | switch (list) { |
1518 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1519 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1520 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1521 | break; |
1522 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1523 | ret = blocking_notifier_chain_unregister( |
1524 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1525 | break; |
1526 | default: | |
1527 | ret = -EINVAL; | |
1528 | } | |
1da177e4 LT |
1529 | |
1530 | return ret; | |
1531 | } | |
1532 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1533 | ||
1534 | ||
1535 | /********************************************************************* | |
1536 | * GOVERNORS * | |
1537 | *********************************************************************/ | |
1538 | ||
1539 | ||
1540 | int __cpufreq_driver_target(struct cpufreq_policy *policy, | |
1541 | unsigned int target_freq, | |
1542 | unsigned int relation) | |
1543 | { | |
1544 | int retval = -EINVAL; | |
7249924e | 1545 | unsigned int old_target_freq = target_freq; |
c32b6b8e | 1546 | |
a7b422cd KRW |
1547 | if (cpufreq_disabled()) |
1548 | return -ENODEV; | |
1549 | ||
7249924e VK |
1550 | /* Make sure that target_freq is within supported range */ |
1551 | if (target_freq > policy->max) | |
1552 | target_freq = policy->max; | |
1553 | if (target_freq < policy->min) | |
1554 | target_freq = policy->min; | |
1555 | ||
1556 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
1557 | policy->cpu, target_freq, relation, old_target_freq); | |
5a1c0228 VK |
1558 | |
1559 | if (target_freq == policy->cur) | |
1560 | return 0; | |
1561 | ||
1c3d85dd RW |
1562 | if (cpufreq_driver->target) |
1563 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
90d45d17 | 1564 | |
1da177e4 LT |
1565 | return retval; |
1566 | } | |
1567 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1568 | ||
1da177e4 LT |
1569 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1570 | unsigned int target_freq, | |
1571 | unsigned int relation) | |
1572 | { | |
f1829e4a | 1573 | int ret = -EINVAL; |
1da177e4 LT |
1574 | |
1575 | policy = cpufreq_cpu_get(policy->cpu); | |
1576 | if (!policy) | |
f1829e4a | 1577 | goto no_policy; |
1da177e4 | 1578 | |
5a01f2e8 | 1579 | if (unlikely(lock_policy_rwsem_write(policy->cpu))) |
f1829e4a | 1580 | goto fail; |
1da177e4 LT |
1581 | |
1582 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1583 | ||
5a01f2e8 | 1584 | unlock_policy_rwsem_write(policy->cpu); |
1da177e4 | 1585 | |
f1829e4a | 1586 | fail: |
1da177e4 | 1587 | cpufreq_cpu_put(policy); |
f1829e4a | 1588 | no_policy: |
1da177e4 LT |
1589 | return ret; |
1590 | } | |
1591 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1592 | ||
bf0b90e3 | 1593 | int __cpufreq_driver_getavg(struct cpufreq_policy *policy, unsigned int cpu) |
dfde5d62 VP |
1594 | { |
1595 | int ret = 0; | |
1596 | ||
d5aaffa9 DB |
1597 | if (cpufreq_disabled()) |
1598 | return ret; | |
1599 | ||
1c3d85dd | 1600 | if (!cpufreq_driver->getavg) |
0676f7f2 VK |
1601 | return 0; |
1602 | ||
dfde5d62 VP |
1603 | policy = cpufreq_cpu_get(policy->cpu); |
1604 | if (!policy) | |
1605 | return -EINVAL; | |
1606 | ||
1c3d85dd | 1607 | ret = cpufreq_driver->getavg(policy, cpu); |
dfde5d62 | 1608 | |
dfde5d62 VP |
1609 | cpufreq_cpu_put(policy); |
1610 | return ret; | |
1611 | } | |
5a01f2e8 | 1612 | EXPORT_SYMBOL_GPL(__cpufreq_driver_getavg); |
dfde5d62 | 1613 | |
153d7f3f | 1614 | /* |
153d7f3f AV |
1615 | * when "event" is CPUFREQ_GOV_LIMITS |
1616 | */ | |
1da177e4 | 1617 | |
e08f5f5b GS |
1618 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
1619 | unsigned int event) | |
1da177e4 | 1620 | { |
cc993cab | 1621 | int ret; |
6afde10c TR |
1622 | |
1623 | /* Only must be defined when default governor is known to have latency | |
1624 | restrictions, like e.g. conservative or ondemand. | |
1625 | That this is the case is already ensured in Kconfig | |
1626 | */ | |
1627 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
1628 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
1629 | #else | |
1630 | struct cpufreq_governor *gov = NULL; | |
1631 | #endif | |
1c256245 TR |
1632 | |
1633 | if (policy->governor->max_transition_latency && | |
1634 | policy->cpuinfo.transition_latency > | |
1635 | policy->governor->max_transition_latency) { | |
6afde10c TR |
1636 | if (!gov) |
1637 | return -EINVAL; | |
1638 | else { | |
1639 | printk(KERN_WARNING "%s governor failed, too long" | |
1640 | " transition latency of HW, fallback" | |
1641 | " to %s governor\n", | |
1642 | policy->governor->name, | |
1643 | gov->name); | |
1644 | policy->governor = gov; | |
1645 | } | |
1c256245 | 1646 | } |
1da177e4 LT |
1647 | |
1648 | if (!try_module_get(policy->governor->owner)) | |
1649 | return -EINVAL; | |
1650 | ||
2d06d8c4 | 1651 | pr_debug("__cpufreq_governor for CPU %u, event %u\n", |
e08f5f5b | 1652 | policy->cpu, event); |
1da177e4 LT |
1653 | ret = policy->governor->governor(policy, event); |
1654 | ||
4d5dcc42 VK |
1655 | if (!ret) { |
1656 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
1657 | policy->governor->initialized++; | |
1658 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
1659 | policy->governor->initialized--; | |
1660 | } | |
b394058f | 1661 | |
e08f5f5b GS |
1662 | /* we keep one module reference alive for |
1663 | each CPU governed by this CPU */ | |
1da177e4 LT |
1664 | if ((event != CPUFREQ_GOV_START) || ret) |
1665 | module_put(policy->governor->owner); | |
1666 | if ((event == CPUFREQ_GOV_STOP) && !ret) | |
1667 | module_put(policy->governor->owner); | |
1668 | ||
1669 | return ret; | |
1670 | } | |
1671 | ||
1672 | ||
1da177e4 LT |
1673 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
1674 | { | |
3bcb09a3 | 1675 | int err; |
1da177e4 LT |
1676 | |
1677 | if (!governor) | |
1678 | return -EINVAL; | |
1679 | ||
a7b422cd KRW |
1680 | if (cpufreq_disabled()) |
1681 | return -ENODEV; | |
1682 | ||
3fc54d37 | 1683 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 1684 | |
b394058f | 1685 | governor->initialized = 0; |
3bcb09a3 JF |
1686 | err = -EBUSY; |
1687 | if (__find_governor(governor->name) == NULL) { | |
1688 | err = 0; | |
1689 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 1690 | } |
1da177e4 | 1691 | |
32ee8c3e | 1692 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 1693 | return err; |
1da177e4 LT |
1694 | } |
1695 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
1696 | ||
1697 | ||
1698 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) | |
1699 | { | |
90e41bac PB |
1700 | #ifdef CONFIG_HOTPLUG_CPU |
1701 | int cpu; | |
1702 | #endif | |
1703 | ||
1da177e4 LT |
1704 | if (!governor) |
1705 | return; | |
1706 | ||
a7b422cd KRW |
1707 | if (cpufreq_disabled()) |
1708 | return; | |
1709 | ||
90e41bac PB |
1710 | #ifdef CONFIG_HOTPLUG_CPU |
1711 | for_each_present_cpu(cpu) { | |
1712 | if (cpu_online(cpu)) | |
1713 | continue; | |
1714 | if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name)) | |
1715 | strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0"); | |
1716 | } | |
1717 | #endif | |
1718 | ||
3fc54d37 | 1719 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 1720 | list_del(&governor->governor_list); |
3fc54d37 | 1721 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
1722 | return; |
1723 | } | |
1724 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
1725 | ||
1726 | ||
1727 | ||
1728 | /********************************************************************* | |
1729 | * POLICY INTERFACE * | |
1730 | *********************************************************************/ | |
1731 | ||
1732 | /** | |
1733 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
1734 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
1735 | * is written | |
1da177e4 LT |
1736 | * |
1737 | * Reads the current cpufreq policy. | |
1738 | */ | |
1739 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
1740 | { | |
1741 | struct cpufreq_policy *cpu_policy; | |
1742 | if (!policy) | |
1743 | return -EINVAL; | |
1744 | ||
1745 | cpu_policy = cpufreq_cpu_get(cpu); | |
1746 | if (!cpu_policy) | |
1747 | return -EINVAL; | |
1748 | ||
1da177e4 | 1749 | memcpy(policy, cpu_policy, sizeof(struct cpufreq_policy)); |
1da177e4 LT |
1750 | |
1751 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
1752 | return 0; |
1753 | } | |
1754 | EXPORT_SYMBOL(cpufreq_get_policy); | |
1755 | ||
1756 | ||
153d7f3f | 1757 | /* |
e08f5f5b GS |
1758 | * data : current policy. |
1759 | * policy : policy to be set. | |
153d7f3f | 1760 | */ |
e08f5f5b GS |
1761 | static int __cpufreq_set_policy(struct cpufreq_policy *data, |
1762 | struct cpufreq_policy *policy) | |
1da177e4 | 1763 | { |
7bd353a9 | 1764 | int ret = 0, failed = 1; |
1da177e4 | 1765 | |
2d06d8c4 | 1766 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu, |
1da177e4 LT |
1767 | policy->min, policy->max); |
1768 | ||
e08f5f5b GS |
1769 | memcpy(&policy->cpuinfo, &data->cpuinfo, |
1770 | sizeof(struct cpufreq_cpuinfo)); | |
1da177e4 | 1771 | |
53391fa2 | 1772 | if (policy->min > data->max || policy->max < data->min) { |
9c9a43ed MD |
1773 | ret = -EINVAL; |
1774 | goto error_out; | |
1775 | } | |
1776 | ||
1da177e4 | 1777 | /* verify the cpu speed can be set within this limit */ |
1c3d85dd | 1778 | ret = cpufreq_driver->verify(policy); |
1da177e4 LT |
1779 | if (ret) |
1780 | goto error_out; | |
1781 | ||
1da177e4 | 1782 | /* adjust if necessary - all reasons */ |
e041c683 AS |
1783 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1784 | CPUFREQ_ADJUST, policy); | |
1da177e4 LT |
1785 | |
1786 | /* adjust if necessary - hardware incompatibility*/ | |
e041c683 AS |
1787 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1788 | CPUFREQ_INCOMPATIBLE, policy); | |
1da177e4 LT |
1789 | |
1790 | /* verify the cpu speed can be set within this limit, | |
1791 | which might be different to the first one */ | |
1c3d85dd | 1792 | ret = cpufreq_driver->verify(policy); |
e041c683 | 1793 | if (ret) |
1da177e4 | 1794 | goto error_out; |
1da177e4 LT |
1795 | |
1796 | /* notification of the new policy */ | |
e041c683 AS |
1797 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1798 | CPUFREQ_NOTIFY, policy); | |
1da177e4 | 1799 | |
7d5e350f DJ |
1800 | data->min = policy->min; |
1801 | data->max = policy->max; | |
1da177e4 | 1802 | |
2d06d8c4 | 1803 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e08f5f5b | 1804 | data->min, data->max); |
1da177e4 | 1805 | |
1c3d85dd | 1806 | if (cpufreq_driver->setpolicy) { |
1da177e4 | 1807 | data->policy = policy->policy; |
2d06d8c4 | 1808 | pr_debug("setting range\n"); |
1c3d85dd | 1809 | ret = cpufreq_driver->setpolicy(policy); |
1da177e4 LT |
1810 | } else { |
1811 | if (policy->governor != data->governor) { | |
1812 | /* save old, working values */ | |
1813 | struct cpufreq_governor *old_gov = data->governor; | |
1814 | ||
2d06d8c4 | 1815 | pr_debug("governor switch\n"); |
1da177e4 LT |
1816 | |
1817 | /* end old governor */ | |
7bd353a9 | 1818 | if (data->governor) { |
1da177e4 | 1819 | __cpufreq_governor(data, CPUFREQ_GOV_STOP); |
955ef483 | 1820 | unlock_policy_rwsem_write(policy->cpu); |
7bd353a9 VK |
1821 | __cpufreq_governor(data, |
1822 | CPUFREQ_GOV_POLICY_EXIT); | |
955ef483 | 1823 | lock_policy_rwsem_write(policy->cpu); |
7bd353a9 | 1824 | } |
1da177e4 LT |
1825 | |
1826 | /* start new governor */ | |
1827 | data->governor = policy->governor; | |
7bd353a9 | 1828 | if (!__cpufreq_governor(data, CPUFREQ_GOV_POLICY_INIT)) { |
955ef483 | 1829 | if (!__cpufreq_governor(data, CPUFREQ_GOV_START)) { |
7bd353a9 | 1830 | failed = 0; |
955ef483 VK |
1831 | } else { |
1832 | unlock_policy_rwsem_write(policy->cpu); | |
7bd353a9 VK |
1833 | __cpufreq_governor(data, |
1834 | CPUFREQ_GOV_POLICY_EXIT); | |
955ef483 VK |
1835 | lock_policy_rwsem_write(policy->cpu); |
1836 | } | |
7bd353a9 VK |
1837 | } |
1838 | ||
1839 | if (failed) { | |
1da177e4 | 1840 | /* new governor failed, so re-start old one */ |
2d06d8c4 | 1841 | pr_debug("starting governor %s failed\n", |
e08f5f5b | 1842 | data->governor->name); |
1da177e4 LT |
1843 | if (old_gov) { |
1844 | data->governor = old_gov; | |
7bd353a9 VK |
1845 | __cpufreq_governor(data, |
1846 | CPUFREQ_GOV_POLICY_INIT); | |
e08f5f5b GS |
1847 | __cpufreq_governor(data, |
1848 | CPUFREQ_GOV_START); | |
1da177e4 LT |
1849 | } |
1850 | ret = -EINVAL; | |
1851 | goto error_out; | |
1852 | } | |
1853 | /* might be a policy change, too, so fall through */ | |
1854 | } | |
2d06d8c4 | 1855 | pr_debug("governor: change or update limits\n"); |
1da177e4 LT |
1856 | __cpufreq_governor(data, CPUFREQ_GOV_LIMITS); |
1857 | } | |
1858 | ||
7d5e350f | 1859 | error_out: |
1da177e4 LT |
1860 | return ret; |
1861 | } | |
1862 | ||
1da177e4 LT |
1863 | /** |
1864 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
1865 | * @cpu: CPU which shall be re-evaluated | |
1866 | * | |
25985edc | 1867 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
1868 | * at different times. |
1869 | */ | |
1870 | int cpufreq_update_policy(unsigned int cpu) | |
1871 | { | |
1872 | struct cpufreq_policy *data = cpufreq_cpu_get(cpu); | |
1873 | struct cpufreq_policy policy; | |
f1829e4a | 1874 | int ret; |
1da177e4 | 1875 | |
f1829e4a JL |
1876 | if (!data) { |
1877 | ret = -ENODEV; | |
1878 | goto no_policy; | |
1879 | } | |
1da177e4 | 1880 | |
f1829e4a JL |
1881 | if (unlikely(lock_policy_rwsem_write(cpu))) { |
1882 | ret = -EINVAL; | |
1883 | goto fail; | |
1884 | } | |
1da177e4 | 1885 | |
2d06d8c4 | 1886 | pr_debug("updating policy for CPU %u\n", cpu); |
7d5e350f | 1887 | memcpy(&policy, data, sizeof(struct cpufreq_policy)); |
1da177e4 LT |
1888 | policy.min = data->user_policy.min; |
1889 | policy.max = data->user_policy.max; | |
1890 | policy.policy = data->user_policy.policy; | |
1891 | policy.governor = data->user_policy.governor; | |
1892 | ||
0961dd0d TR |
1893 | /* BIOS might change freq behind our back |
1894 | -> ask driver for current freq and notify governors about a change */ | |
1c3d85dd RW |
1895 | if (cpufreq_driver->get) { |
1896 | policy.cur = cpufreq_driver->get(cpu); | |
a85f7bd3 | 1897 | if (!data->cur) { |
2d06d8c4 | 1898 | pr_debug("Driver did not initialize current freq"); |
a85f7bd3 TR |
1899 | data->cur = policy.cur; |
1900 | } else { | |
1c3d85dd | 1901 | if (data->cur != policy.cur && cpufreq_driver->target) |
e08f5f5b GS |
1902 | cpufreq_out_of_sync(cpu, data->cur, |
1903 | policy.cur); | |
a85f7bd3 | 1904 | } |
0961dd0d TR |
1905 | } |
1906 | ||
1da177e4 LT |
1907 | ret = __cpufreq_set_policy(data, &policy); |
1908 | ||
5a01f2e8 VP |
1909 | unlock_policy_rwsem_write(cpu); |
1910 | ||
f1829e4a | 1911 | fail: |
1da177e4 | 1912 | cpufreq_cpu_put(data); |
f1829e4a | 1913 | no_policy: |
1da177e4 LT |
1914 | return ret; |
1915 | } | |
1916 | EXPORT_SYMBOL(cpufreq_update_policy); | |
1917 | ||
dd184a01 | 1918 | static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
1919 | unsigned long action, void *hcpu) |
1920 | { | |
1921 | unsigned int cpu = (unsigned long)hcpu; | |
8a25a2fd | 1922 | struct device *dev; |
c32b6b8e | 1923 | |
8a25a2fd KS |
1924 | dev = get_cpu_device(cpu); |
1925 | if (dev) { | |
c32b6b8e AR |
1926 | switch (action) { |
1927 | case CPU_ONLINE: | |
8a25a2fd | 1928 | cpufreq_add_dev(dev, NULL); |
c32b6b8e AR |
1929 | break; |
1930 | case CPU_DOWN_PREPARE: | |
a66b2e50 | 1931 | case CPU_UP_CANCELED_FROZEN: |
8a25a2fd | 1932 | __cpufreq_remove_dev(dev, NULL); |
c32b6b8e | 1933 | break; |
5a01f2e8 | 1934 | case CPU_DOWN_FAILED: |
8a25a2fd | 1935 | cpufreq_add_dev(dev, NULL); |
c32b6b8e AR |
1936 | break; |
1937 | } | |
1938 | } | |
1939 | return NOTIFY_OK; | |
1940 | } | |
1941 | ||
9c36f746 | 1942 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
c32b6b8e AR |
1943 | .notifier_call = cpufreq_cpu_callback, |
1944 | }; | |
1da177e4 LT |
1945 | |
1946 | /********************************************************************* | |
1947 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
1948 | *********************************************************************/ | |
1949 | ||
1950 | /** | |
1951 | * cpufreq_register_driver - register a CPU Frequency driver | |
1952 | * @driver_data: A struct cpufreq_driver containing the values# | |
1953 | * submitted by the CPU Frequency driver. | |
1954 | * | |
32ee8c3e | 1955 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 1956 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 1957 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
1958 | * |
1959 | */ | |
221dee28 | 1960 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
1961 | { |
1962 | unsigned long flags; | |
1963 | int ret; | |
1964 | ||
a7b422cd KRW |
1965 | if (cpufreq_disabled()) |
1966 | return -ENODEV; | |
1967 | ||
1da177e4 LT |
1968 | if (!driver_data || !driver_data->verify || !driver_data->init || |
1969 | ((!driver_data->setpolicy) && (!driver_data->target))) | |
1970 | return -EINVAL; | |
1971 | ||
2d06d8c4 | 1972 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 LT |
1973 | |
1974 | if (driver_data->setpolicy) | |
1975 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
1976 | ||
0d1857a1 | 1977 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 1978 | if (cpufreq_driver) { |
0d1857a1 | 1979 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
1980 | return -EBUSY; |
1981 | } | |
1c3d85dd | 1982 | cpufreq_driver = driver_data; |
0d1857a1 | 1983 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1984 | |
8a25a2fd | 1985 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab JS |
1986 | if (ret) |
1987 | goto err_null_driver; | |
1da177e4 | 1988 | |
1c3d85dd | 1989 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) { |
1da177e4 LT |
1990 | int i; |
1991 | ret = -ENODEV; | |
1992 | ||
1993 | /* check for at least one working CPU */ | |
7a6aedfa MT |
1994 | for (i = 0; i < nr_cpu_ids; i++) |
1995 | if (cpu_possible(i) && per_cpu(cpufreq_cpu_data, i)) { | |
1da177e4 | 1996 | ret = 0; |
7a6aedfa MT |
1997 | break; |
1998 | } | |
1da177e4 LT |
1999 | |
2000 | /* if all ->init() calls failed, unregister */ | |
2001 | if (ret) { | |
2d06d8c4 | 2002 | pr_debug("no CPU initialized for driver %s\n", |
e08f5f5b | 2003 | driver_data->name); |
8a25a2fd | 2004 | goto err_if_unreg; |
1da177e4 LT |
2005 | } |
2006 | } | |
2007 | ||
8f5bc2ab | 2008 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2009 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2010 | |
8f5bc2ab | 2011 | return 0; |
8a25a2fd KS |
2012 | err_if_unreg: |
2013 | subsys_interface_unregister(&cpufreq_interface); | |
8f5bc2ab | 2014 | err_null_driver: |
0d1857a1 | 2015 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2016 | cpufreq_driver = NULL; |
0d1857a1 | 2017 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4d34a67d | 2018 | return ret; |
1da177e4 LT |
2019 | } |
2020 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2021 | ||
2022 | ||
2023 | /** | |
2024 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2025 | * | |
32ee8c3e | 2026 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2027 | * the right to do so, i.e. if you have succeeded in initialising before! |
2028 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2029 | * currently not initialised. | |
2030 | */ | |
221dee28 | 2031 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2032 | { |
2033 | unsigned long flags; | |
2034 | ||
1c3d85dd | 2035 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2036 | return -EINVAL; |
1da177e4 | 2037 | |
2d06d8c4 | 2038 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2039 | |
8a25a2fd | 2040 | subsys_interface_unregister(&cpufreq_interface); |
65edc68c | 2041 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2042 | |
0d1857a1 | 2043 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2044 | cpufreq_driver = NULL; |
0d1857a1 | 2045 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
2046 | |
2047 | return 0; | |
2048 | } | |
2049 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2050 | |
2051 | static int __init cpufreq_core_init(void) | |
2052 | { | |
2053 | int cpu; | |
2054 | ||
a7b422cd KRW |
2055 | if (cpufreq_disabled()) |
2056 | return -ENODEV; | |
2057 | ||
5a01f2e8 | 2058 | for_each_possible_cpu(cpu) { |
f1625066 | 2059 | per_cpu(cpufreq_policy_cpu, cpu) = -1; |
5a01f2e8 VP |
2060 | init_rwsem(&per_cpu(cpu_policy_rwsem, cpu)); |
2061 | } | |
8aa84ad8 | 2062 | |
2361be23 | 2063 | cpufreq_global_kobject = kobject_create(); |
8aa84ad8 | 2064 | BUG_ON(!cpufreq_global_kobject); |
e00e56df | 2065 | register_syscore_ops(&cpufreq_syscore_ops); |
8aa84ad8 | 2066 | |
5a01f2e8 VP |
2067 | return 0; |
2068 | } | |
5a01f2e8 | 2069 | core_initcall(cpufreq_core_init); |