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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
2f0aea93 | 29 | #include <linux/suspend.h> |
90de2a4a | 30 | #include <linux/syscore_ops.h> |
5ff0a268 | 31 | #include <linux/tick.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
1da177e4 | 34 | /** |
cd878479 | 35 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
36 | * level driver of CPUFreq support, and its spinlock. This lock |
37 | * also protects the cpufreq_cpu_data array. | |
38 | */ | |
1c3d85dd | 39 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 40 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
8414809c | 41 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback); |
bb176f7d | 42 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
6f1e4efd | 43 | DEFINE_MUTEX(cpufreq_governor_lock); |
c88a1f8b | 44 | static LIST_HEAD(cpufreq_policy_list); |
bb176f7d | 45 | |
084f3493 | 46 | /* This one keeps track of the previously set governor of a removed CPU */ |
e77b89f1 | 47 | static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor); |
1da177e4 | 48 | |
2f0aea93 VK |
49 | /* Flag to suspend/resume CPUFreq governors */ |
50 | static bool cpufreq_suspended; | |
1da177e4 | 51 | |
9c0ebcf7 VK |
52 | static inline bool has_target(void) |
53 | { | |
54 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
55 | } | |
56 | ||
6eed9404 VK |
57 | /* |
58 | * rwsem to guarantee that cpufreq driver module doesn't unload during critical | |
59 | * sections | |
60 | */ | |
61 | static DECLARE_RWSEM(cpufreq_rwsem); | |
62 | ||
1da177e4 | 63 | /* internal prototypes */ |
29464f28 DJ |
64 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
65 | unsigned int event); | |
d92d50a4 | 66 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
65f27f38 | 67 | static void handle_update(struct work_struct *work); |
1da177e4 LT |
68 | |
69 | /** | |
32ee8c3e DJ |
70 | * Two notifier lists: the "policy" list is involved in the |
71 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
72 | * "transition" list for kernel code that needs to handle |
73 | * changes to devices when the CPU clock speed changes. | |
74 | * The mutex locks both lists. | |
75 | */ | |
e041c683 | 76 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 77 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 78 | |
74212ca4 | 79 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
80 | static int __init init_cpufreq_transition_notifier_list(void) |
81 | { | |
82 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 83 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
84 | return 0; |
85 | } | |
b3438f82 | 86 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 87 | |
a7b422cd | 88 | static int off __read_mostly; |
da584455 | 89 | static int cpufreq_disabled(void) |
a7b422cd KRW |
90 | { |
91 | return off; | |
92 | } | |
93 | void disable_cpufreq(void) | |
94 | { | |
95 | off = 1; | |
96 | } | |
1da177e4 | 97 | static LIST_HEAD(cpufreq_governor_list); |
29464f28 | 98 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 99 | |
4d5dcc42 VK |
100 | bool have_governor_per_policy(void) |
101 | { | |
0b981e70 | 102 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 103 | } |
3f869d6d | 104 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 105 | |
944e9a03 VK |
106 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
107 | { | |
108 | if (have_governor_per_policy()) | |
109 | return &policy->kobj; | |
110 | else | |
111 | return cpufreq_global_kobject; | |
112 | } | |
113 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
114 | ||
72a4ce34 VK |
115 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
116 | { | |
117 | u64 idle_time; | |
118 | u64 cur_wall_time; | |
119 | u64 busy_time; | |
120 | ||
121 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
122 | ||
123 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
124 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
125 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
126 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
127 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
128 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
129 | ||
130 | idle_time = cur_wall_time - busy_time; | |
131 | if (wall) | |
132 | *wall = cputime_to_usecs(cur_wall_time); | |
133 | ||
134 | return cputime_to_usecs(idle_time); | |
135 | } | |
136 | ||
137 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
138 | { | |
139 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
140 | ||
141 | if (idle_time == -1ULL) | |
142 | return get_cpu_idle_time_jiffy(cpu, wall); | |
143 | else if (!io_busy) | |
144 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
145 | ||
146 | return idle_time; | |
147 | } | |
148 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
149 | ||
70e9e778 VK |
150 | /* |
151 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
152 | * drivers of SMP systems. It will do following: | |
153 | * - validate & show freq table passed | |
154 | * - set policies transition latency | |
155 | * - policy->cpus with all possible CPUs | |
156 | */ | |
157 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
158 | struct cpufreq_frequency_table *table, | |
159 | unsigned int transition_latency) | |
160 | { | |
161 | int ret; | |
162 | ||
163 | ret = cpufreq_table_validate_and_show(policy, table); | |
164 | if (ret) { | |
165 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
166 | return ret; | |
167 | } | |
168 | ||
169 | policy->cpuinfo.transition_latency = transition_latency; | |
170 | ||
171 | /* | |
172 | * The driver only supports the SMP configuartion where all processors | |
173 | * share the clock and voltage and clock. | |
174 | */ | |
175 | cpumask_setall(policy->cpus); | |
176 | ||
177 | return 0; | |
178 | } | |
179 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
180 | ||
652ed95d VK |
181 | unsigned int cpufreq_generic_get(unsigned int cpu) |
182 | { | |
183 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
184 | ||
185 | if (!policy || IS_ERR(policy->clk)) { | |
e837f9b5 JP |
186 | pr_err("%s: No %s associated to cpu: %d\n", |
187 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
188 | return 0; |
189 | } | |
190 | ||
191 | return clk_get_rate(policy->clk) / 1000; | |
192 | } | |
193 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
194 | ||
e0b3165b VK |
195 | /* Only for cpufreq core internal use */ |
196 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) | |
197 | { | |
198 | return per_cpu(cpufreq_cpu_data, cpu); | |
199 | } | |
200 | ||
6eed9404 | 201 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 202 | { |
6eed9404 | 203 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
204 | unsigned long flags; |
205 | ||
6eed9404 VK |
206 | if (cpufreq_disabled() || (cpu >= nr_cpu_ids)) |
207 | return NULL; | |
208 | ||
209 | if (!down_read_trylock(&cpufreq_rwsem)) | |
210 | return NULL; | |
1da177e4 LT |
211 | |
212 | /* get the cpufreq driver */ | |
1c3d85dd | 213 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 214 | |
6eed9404 VK |
215 | if (cpufreq_driver) { |
216 | /* get the CPU */ | |
217 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
218 | if (policy) | |
219 | kobject_get(&policy->kobj); | |
220 | } | |
1da177e4 | 221 | |
6eed9404 | 222 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 223 | |
3a3e9e06 | 224 | if (!policy) |
6eed9404 | 225 | up_read(&cpufreq_rwsem); |
1da177e4 | 226 | |
3a3e9e06 | 227 | return policy; |
a9144436 | 228 | } |
1da177e4 LT |
229 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
230 | ||
3a3e9e06 | 231 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 232 | { |
d5aaffa9 DB |
233 | if (cpufreq_disabled()) |
234 | return; | |
235 | ||
6eed9404 VK |
236 | kobject_put(&policy->kobj); |
237 | up_read(&cpufreq_rwsem); | |
1da177e4 LT |
238 | } |
239 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
240 | ||
1da177e4 LT |
241 | /********************************************************************* |
242 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
243 | *********************************************************************/ | |
244 | ||
245 | /** | |
246 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
247 | * | |
248 | * This function alters the system "loops_per_jiffy" for the clock | |
249 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 250 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
251 | * per-CPU loops_per_jiffy value wherever possible. |
252 | */ | |
253 | #ifndef CONFIG_SMP | |
254 | static unsigned long l_p_j_ref; | |
bb176f7d | 255 | static unsigned int l_p_j_ref_freq; |
1da177e4 | 256 | |
858119e1 | 257 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 LT |
258 | { |
259 | if (ci->flags & CPUFREQ_CONST_LOOPS) | |
260 | return; | |
261 | ||
262 | if (!l_p_j_ref_freq) { | |
263 | l_p_j_ref = loops_per_jiffy; | |
264 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
265 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
266 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 267 | } |
0b443ead | 268 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
269 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
270 | ci->new); | |
e837f9b5 JP |
271 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
272 | loops_per_jiffy, ci->new); | |
1da177e4 LT |
273 | } |
274 | } | |
275 | #else | |
e08f5f5b GS |
276 | static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
277 | { | |
278 | return; | |
279 | } | |
1da177e4 LT |
280 | #endif |
281 | ||
0956df9c | 282 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 283 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
284 | { |
285 | BUG_ON(irqs_disabled()); | |
286 | ||
d5aaffa9 DB |
287 | if (cpufreq_disabled()) |
288 | return; | |
289 | ||
1c3d85dd | 290 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 291 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 292 | state, freqs->new); |
1da177e4 | 293 | |
1da177e4 | 294 | switch (state) { |
e4472cb3 | 295 | |
1da177e4 | 296 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 297 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
298 | * which is not equal to what the cpufreq core thinks is |
299 | * "old frequency". | |
1da177e4 | 300 | */ |
1c3d85dd | 301 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
302 | if ((policy) && (policy->cpu == freqs->cpu) && |
303 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
304 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
305 | freqs->old, policy->cur); | |
e4472cb3 | 306 | freqs->old = policy->cur; |
1da177e4 LT |
307 | } |
308 | } | |
b4dfdbb3 | 309 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 310 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
311 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
312 | break; | |
e4472cb3 | 313 | |
1da177e4 LT |
314 | case CPUFREQ_POSTCHANGE: |
315 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
316 | pr_debug("FREQ: %lu - CPU: %lu\n", |
317 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 318 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 319 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 320 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
321 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
322 | policy->cur = freqs->new; | |
1da177e4 LT |
323 | break; |
324 | } | |
1da177e4 | 325 | } |
bb176f7d | 326 | |
b43a7ffb VK |
327 | /** |
328 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
329 | * on frequency transition. | |
330 | * | |
331 | * This function calls the transition notifiers and the "adjust_jiffies" | |
332 | * function. It is called twice on all CPU frequency changes that have | |
333 | * external effects. | |
334 | */ | |
236a9800 | 335 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
336 | struct cpufreq_freqs *freqs, unsigned int state) |
337 | { | |
338 | for_each_cpu(freqs->cpu, policy->cpus) | |
339 | __cpufreq_notify_transition(policy, freqs, state); | |
340 | } | |
1da177e4 | 341 | |
f7ba3b41 | 342 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 343 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
344 | struct cpufreq_freqs *freqs, int transition_failed) |
345 | { | |
346 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
347 | if (!transition_failed) | |
348 | return; | |
349 | ||
350 | swap(freqs->old, freqs->new); | |
351 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
352 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
353 | } | |
f7ba3b41 | 354 | |
12478cf0 SB |
355 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
356 | struct cpufreq_freqs *freqs) | |
357 | { | |
ca654dc3 SB |
358 | |
359 | /* | |
360 | * Catch double invocations of _begin() which lead to self-deadlock. | |
361 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
362 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
363 | * double invocations are very low. Moreover, there are scenarios | |
364 | * where these checks can emit false-positive warnings in these | |
365 | * drivers; so we avoid that by skipping them altogether. | |
366 | */ | |
367 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
368 | && current == policy->transition_task); | |
369 | ||
12478cf0 SB |
370 | wait: |
371 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
372 | ||
373 | spin_lock(&policy->transition_lock); | |
374 | ||
375 | if (unlikely(policy->transition_ongoing)) { | |
376 | spin_unlock(&policy->transition_lock); | |
377 | goto wait; | |
378 | } | |
379 | ||
380 | policy->transition_ongoing = true; | |
ca654dc3 | 381 | policy->transition_task = current; |
12478cf0 SB |
382 | |
383 | spin_unlock(&policy->transition_lock); | |
384 | ||
385 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
386 | } | |
387 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
388 | ||
389 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
390 | struct cpufreq_freqs *freqs, int transition_failed) | |
391 | { | |
392 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
393 | return; | |
394 | ||
395 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
396 | ||
397 | policy->transition_ongoing = false; | |
ca654dc3 | 398 | policy->transition_task = NULL; |
12478cf0 SB |
399 | |
400 | wake_up(&policy->transition_wait); | |
401 | } | |
402 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
403 | ||
1da177e4 | 404 | |
1da177e4 LT |
405 | /********************************************************************* |
406 | * SYSFS INTERFACE * | |
407 | *********************************************************************/ | |
8a5c74a1 | 408 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
409 | struct attribute *attr, char *buf) |
410 | { | |
411 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
412 | } | |
413 | ||
414 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
415 | const char *buf, size_t count) | |
416 | { | |
417 | int ret, enable; | |
418 | ||
419 | ret = sscanf(buf, "%d", &enable); | |
420 | if (ret != 1 || enable < 0 || enable > 1) | |
421 | return -EINVAL; | |
422 | ||
423 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
424 | pr_err("%s: Cannot %s BOOST!\n", |
425 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
426 | return -EINVAL; |
427 | } | |
428 | ||
e837f9b5 JP |
429 | pr_debug("%s: cpufreq BOOST %s\n", |
430 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
431 | |
432 | return count; | |
433 | } | |
434 | define_one_global_rw(boost); | |
1da177e4 | 435 | |
42f91fa1 | 436 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
437 | { |
438 | struct cpufreq_governor *t; | |
439 | ||
440 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) | |
7c4f4539 | 441 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
442 | return t; |
443 | ||
444 | return NULL; | |
445 | } | |
446 | ||
1da177e4 LT |
447 | /** |
448 | * cpufreq_parse_governor - parse a governor string | |
449 | */ | |
905d77cd | 450 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
451 | struct cpufreq_governor **governor) |
452 | { | |
3bcb09a3 | 453 | int err = -EINVAL; |
1c3d85dd RW |
454 | |
455 | if (!cpufreq_driver) | |
3bcb09a3 JF |
456 | goto out; |
457 | ||
1c3d85dd | 458 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 459 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 460 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 461 | err = 0; |
7c4f4539 | 462 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 463 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 464 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 465 | err = 0; |
1da177e4 | 466 | } |
2e1cc3a5 | 467 | } else { |
1da177e4 | 468 | struct cpufreq_governor *t; |
3bcb09a3 | 469 | |
3fc54d37 | 470 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 471 | |
42f91fa1 | 472 | t = find_governor(str_governor); |
3bcb09a3 | 473 | |
ea714970 | 474 | if (t == NULL) { |
1a8e1463 | 475 | int ret; |
ea714970 | 476 | |
1a8e1463 KC |
477 | mutex_unlock(&cpufreq_governor_mutex); |
478 | ret = request_module("cpufreq_%s", str_governor); | |
479 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 480 | |
1a8e1463 | 481 | if (ret == 0) |
42f91fa1 | 482 | t = find_governor(str_governor); |
ea714970 JF |
483 | } |
484 | ||
3bcb09a3 JF |
485 | if (t != NULL) { |
486 | *governor = t; | |
487 | err = 0; | |
1da177e4 | 488 | } |
3bcb09a3 | 489 | |
3fc54d37 | 490 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 491 | } |
29464f28 | 492 | out: |
3bcb09a3 | 493 | return err; |
1da177e4 | 494 | } |
1da177e4 | 495 | |
1da177e4 | 496 | /** |
e08f5f5b GS |
497 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
498 | * print out cpufreq information | |
1da177e4 LT |
499 | * |
500 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
501 | * "unsigned int". | |
502 | */ | |
503 | ||
32ee8c3e DJ |
504 | #define show_one(file_name, object) \ |
505 | static ssize_t show_##file_name \ | |
905d77cd | 506 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 507 | { \ |
29464f28 | 508 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
509 | } |
510 | ||
511 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
512 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 513 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
514 | show_one(scaling_min_freq, min); |
515 | show_one(scaling_max_freq, max); | |
c034b02e | 516 | |
09347b29 | 517 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
518 | { |
519 | ssize_t ret; | |
520 | ||
521 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
522 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
523 | else | |
524 | ret = sprintf(buf, "%u\n", policy->cur); | |
525 | return ret; | |
526 | } | |
1da177e4 | 527 | |
037ce839 | 528 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 529 | struct cpufreq_policy *new_policy); |
7970e08b | 530 | |
1da177e4 LT |
531 | /** |
532 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
533 | */ | |
534 | #define store_one(file_name, object) \ | |
535 | static ssize_t store_##file_name \ | |
905d77cd | 536 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 537 | { \ |
619c144c | 538 | int ret, temp; \ |
1da177e4 LT |
539 | struct cpufreq_policy new_policy; \ |
540 | \ | |
541 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ | |
542 | if (ret) \ | |
543 | return -EINVAL; \ | |
544 | \ | |
29464f28 | 545 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
546 | if (ret != 1) \ |
547 | return -EINVAL; \ | |
548 | \ | |
619c144c | 549 | temp = new_policy.object; \ |
037ce839 | 550 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
551 | if (!ret) \ |
552 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
553 | \ |
554 | return ret ? ret : count; \ | |
555 | } | |
556 | ||
29464f28 DJ |
557 | store_one(scaling_min_freq, min); |
558 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
559 | |
560 | /** | |
561 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
562 | */ | |
905d77cd DJ |
563 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
564 | char *buf) | |
1da177e4 | 565 | { |
d92d50a4 | 566 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
567 | if (!cur_freq) |
568 | return sprintf(buf, "<unknown>"); | |
569 | return sprintf(buf, "%u\n", cur_freq); | |
570 | } | |
571 | ||
1da177e4 LT |
572 | /** |
573 | * show_scaling_governor - show the current policy for the specified CPU | |
574 | */ | |
905d77cd | 575 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 576 | { |
29464f28 | 577 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
578 | return sprintf(buf, "powersave\n"); |
579 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
580 | return sprintf(buf, "performance\n"); | |
581 | else if (policy->governor) | |
4b972f0b | 582 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 583 | policy->governor->name); |
1da177e4 LT |
584 | return -EINVAL; |
585 | } | |
586 | ||
1da177e4 LT |
587 | /** |
588 | * store_scaling_governor - store policy for the specified CPU | |
589 | */ | |
905d77cd DJ |
590 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
591 | const char *buf, size_t count) | |
1da177e4 | 592 | { |
5136fa56 | 593 | int ret; |
1da177e4 LT |
594 | char str_governor[16]; |
595 | struct cpufreq_policy new_policy; | |
596 | ||
597 | ret = cpufreq_get_policy(&new_policy, policy->cpu); | |
598 | if (ret) | |
599 | return ret; | |
600 | ||
29464f28 | 601 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
602 | if (ret != 1) |
603 | return -EINVAL; | |
604 | ||
e08f5f5b GS |
605 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
606 | &new_policy.governor)) | |
1da177e4 LT |
607 | return -EINVAL; |
608 | ||
037ce839 | 609 | ret = cpufreq_set_policy(policy, &new_policy); |
7970e08b TR |
610 | |
611 | policy->user_policy.policy = policy->policy; | |
612 | policy->user_policy.governor = policy->governor; | |
7970e08b | 613 | |
e08f5f5b GS |
614 | if (ret) |
615 | return ret; | |
616 | else | |
617 | return count; | |
1da177e4 LT |
618 | } |
619 | ||
620 | /** | |
621 | * show_scaling_driver - show the cpufreq driver currently loaded | |
622 | */ | |
905d77cd | 623 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 624 | { |
1c3d85dd | 625 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
626 | } |
627 | ||
628 | /** | |
629 | * show_scaling_available_governors - show the available CPUfreq governors | |
630 | */ | |
905d77cd DJ |
631 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
632 | char *buf) | |
1da177e4 LT |
633 | { |
634 | ssize_t i = 0; | |
635 | struct cpufreq_governor *t; | |
636 | ||
9c0ebcf7 | 637 | if (!has_target()) { |
1da177e4 LT |
638 | i += sprintf(buf, "performance powersave"); |
639 | goto out; | |
640 | } | |
641 | ||
642 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { | |
29464f28 DJ |
643 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
644 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 645 | goto out; |
4b972f0b | 646 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 647 | } |
7d5e350f | 648 | out: |
1da177e4 LT |
649 | i += sprintf(&buf[i], "\n"); |
650 | return i; | |
651 | } | |
e8628dd0 | 652 | |
f4fd3797 | 653 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
654 | { |
655 | ssize_t i = 0; | |
656 | unsigned int cpu; | |
657 | ||
835481d9 | 658 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
659 | if (i) |
660 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
661 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
662 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 663 | break; |
1da177e4 LT |
664 | } |
665 | i += sprintf(&buf[i], "\n"); | |
666 | return i; | |
667 | } | |
f4fd3797 | 668 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 669 | |
e8628dd0 DW |
670 | /** |
671 | * show_related_cpus - show the CPUs affected by each transition even if | |
672 | * hw coordination is in use | |
673 | */ | |
674 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
675 | { | |
f4fd3797 | 676 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
677 | } |
678 | ||
679 | /** | |
680 | * show_affected_cpus - show the CPUs affected by each transition | |
681 | */ | |
682 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
683 | { | |
f4fd3797 | 684 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
685 | } |
686 | ||
9e76988e | 687 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 688 | const char *buf, size_t count) |
9e76988e VP |
689 | { |
690 | unsigned int freq = 0; | |
691 | unsigned int ret; | |
692 | ||
879000f9 | 693 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
694 | return -EINVAL; |
695 | ||
696 | ret = sscanf(buf, "%u", &freq); | |
697 | if (ret != 1) | |
698 | return -EINVAL; | |
699 | ||
700 | policy->governor->store_setspeed(policy, freq); | |
701 | ||
702 | return count; | |
703 | } | |
704 | ||
705 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
706 | { | |
879000f9 | 707 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
708 | return sprintf(buf, "<unsupported>\n"); |
709 | ||
710 | return policy->governor->show_setspeed(policy, buf); | |
711 | } | |
1da177e4 | 712 | |
e2f74f35 | 713 | /** |
8bf1ac72 | 714 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
715 | */ |
716 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
717 | { | |
718 | unsigned int limit; | |
719 | int ret; | |
1c3d85dd RW |
720 | if (cpufreq_driver->bios_limit) { |
721 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
722 | if (!ret) |
723 | return sprintf(buf, "%u\n", limit); | |
724 | } | |
725 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
726 | } | |
727 | ||
6dad2a29 BP |
728 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
729 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
730 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
731 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
732 | cpufreq_freq_attr_ro(scaling_available_governors); | |
733 | cpufreq_freq_attr_ro(scaling_driver); | |
734 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
735 | cpufreq_freq_attr_ro(bios_limit); | |
736 | cpufreq_freq_attr_ro(related_cpus); | |
737 | cpufreq_freq_attr_ro(affected_cpus); | |
738 | cpufreq_freq_attr_rw(scaling_min_freq); | |
739 | cpufreq_freq_attr_rw(scaling_max_freq); | |
740 | cpufreq_freq_attr_rw(scaling_governor); | |
741 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 742 | |
905d77cd | 743 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
744 | &cpuinfo_min_freq.attr, |
745 | &cpuinfo_max_freq.attr, | |
ed129784 | 746 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
747 | &scaling_min_freq.attr, |
748 | &scaling_max_freq.attr, | |
749 | &affected_cpus.attr, | |
e8628dd0 | 750 | &related_cpus.attr, |
1da177e4 LT |
751 | &scaling_governor.attr, |
752 | &scaling_driver.attr, | |
753 | &scaling_available_governors.attr, | |
9e76988e | 754 | &scaling_setspeed.attr, |
1da177e4 LT |
755 | NULL |
756 | }; | |
757 | ||
29464f28 DJ |
758 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
759 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 760 | |
29464f28 | 761 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 762 | { |
905d77cd DJ |
763 | struct cpufreq_policy *policy = to_policy(kobj); |
764 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 765 | ssize_t ret; |
6eed9404 VK |
766 | |
767 | if (!down_read_trylock(&cpufreq_rwsem)) | |
1b750e3b | 768 | return -EINVAL; |
5a01f2e8 | 769 | |
ad7722da | 770 | down_read(&policy->rwsem); |
5a01f2e8 | 771 | |
e08f5f5b GS |
772 | if (fattr->show) |
773 | ret = fattr->show(policy, buf); | |
774 | else | |
775 | ret = -EIO; | |
776 | ||
ad7722da | 777 | up_read(&policy->rwsem); |
6eed9404 | 778 | up_read(&cpufreq_rwsem); |
1b750e3b | 779 | |
1da177e4 LT |
780 | return ret; |
781 | } | |
782 | ||
905d77cd DJ |
783 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
784 | const char *buf, size_t count) | |
1da177e4 | 785 | { |
905d77cd DJ |
786 | struct cpufreq_policy *policy = to_policy(kobj); |
787 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 788 | ssize_t ret = -EINVAL; |
6eed9404 | 789 | |
4f750c93 SB |
790 | get_online_cpus(); |
791 | ||
792 | if (!cpu_online(policy->cpu)) | |
793 | goto unlock; | |
794 | ||
6eed9404 | 795 | if (!down_read_trylock(&cpufreq_rwsem)) |
4f750c93 | 796 | goto unlock; |
5a01f2e8 | 797 | |
ad7722da | 798 | down_write(&policy->rwsem); |
5a01f2e8 | 799 | |
e08f5f5b GS |
800 | if (fattr->store) |
801 | ret = fattr->store(policy, buf, count); | |
802 | else | |
803 | ret = -EIO; | |
804 | ||
ad7722da | 805 | up_write(&policy->rwsem); |
6eed9404 | 806 | |
6eed9404 | 807 | up_read(&cpufreq_rwsem); |
4f750c93 SB |
808 | unlock: |
809 | put_online_cpus(); | |
810 | ||
1da177e4 LT |
811 | return ret; |
812 | } | |
813 | ||
905d77cd | 814 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 815 | { |
905d77cd | 816 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 817 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
818 | complete(&policy->kobj_unregister); |
819 | } | |
820 | ||
52cf25d0 | 821 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
822 | .show = show, |
823 | .store = store, | |
824 | }; | |
825 | ||
826 | static struct kobj_type ktype_cpufreq = { | |
827 | .sysfs_ops = &sysfs_ops, | |
828 | .default_attrs = default_attrs, | |
829 | .release = cpufreq_sysfs_release, | |
830 | }; | |
831 | ||
2361be23 VK |
832 | struct kobject *cpufreq_global_kobject; |
833 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
834 | ||
835 | static int cpufreq_global_kobject_usage; | |
836 | ||
837 | int cpufreq_get_global_kobject(void) | |
838 | { | |
839 | if (!cpufreq_global_kobject_usage++) | |
840 | return kobject_add(cpufreq_global_kobject, | |
841 | &cpu_subsys.dev_root->kobj, "%s", "cpufreq"); | |
842 | ||
843 | return 0; | |
844 | } | |
845 | EXPORT_SYMBOL(cpufreq_get_global_kobject); | |
846 | ||
847 | void cpufreq_put_global_kobject(void) | |
848 | { | |
849 | if (!--cpufreq_global_kobject_usage) | |
850 | kobject_del(cpufreq_global_kobject); | |
851 | } | |
852 | EXPORT_SYMBOL(cpufreq_put_global_kobject); | |
853 | ||
854 | int cpufreq_sysfs_create_file(const struct attribute *attr) | |
855 | { | |
856 | int ret = cpufreq_get_global_kobject(); | |
857 | ||
858 | if (!ret) { | |
859 | ret = sysfs_create_file(cpufreq_global_kobject, attr); | |
860 | if (ret) | |
861 | cpufreq_put_global_kobject(); | |
862 | } | |
863 | ||
864 | return ret; | |
865 | } | |
866 | EXPORT_SYMBOL(cpufreq_sysfs_create_file); | |
867 | ||
868 | void cpufreq_sysfs_remove_file(const struct attribute *attr) | |
869 | { | |
870 | sysfs_remove_file(cpufreq_global_kobject, attr); | |
871 | cpufreq_put_global_kobject(); | |
872 | } | |
873 | EXPORT_SYMBOL(cpufreq_sysfs_remove_file); | |
874 | ||
19d6f7ec | 875 | /* symlink affected CPUs */ |
308b60e7 | 876 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
877 | { |
878 | unsigned int j; | |
879 | int ret = 0; | |
880 | ||
881 | for_each_cpu(j, policy->cpus) { | |
8a25a2fd | 882 | struct device *cpu_dev; |
19d6f7ec | 883 | |
308b60e7 | 884 | if (j == policy->cpu) |
19d6f7ec | 885 | continue; |
19d6f7ec | 886 | |
e8fdde10 | 887 | pr_debug("Adding link for CPU: %u\n", j); |
8a25a2fd KS |
888 | cpu_dev = get_cpu_device(j); |
889 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
19d6f7ec | 890 | "cpufreq"); |
71c3461e RW |
891 | if (ret) |
892 | break; | |
19d6f7ec DJ |
893 | } |
894 | return ret; | |
895 | } | |
896 | ||
308b60e7 | 897 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy, |
8a25a2fd | 898 | struct device *dev) |
909a694e DJ |
899 | { |
900 | struct freq_attr **drv_attr; | |
909a694e | 901 | int ret = 0; |
909a694e | 902 | |
909a694e | 903 | /* set up files for this cpu device */ |
1c3d85dd | 904 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 905 | while (drv_attr && *drv_attr) { |
909a694e DJ |
906 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
907 | if (ret) | |
6d4e81ed | 908 | return ret; |
909a694e DJ |
909 | drv_attr++; |
910 | } | |
1c3d85dd | 911 | if (cpufreq_driver->get) { |
909a694e DJ |
912 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
913 | if (ret) | |
6d4e81ed | 914 | return ret; |
909a694e | 915 | } |
c034b02e DB |
916 | |
917 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
918 | if (ret) | |
6d4e81ed | 919 | return ret; |
c034b02e | 920 | |
1c3d85dd | 921 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
922 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
923 | if (ret) | |
6d4e81ed | 924 | return ret; |
e2f74f35 | 925 | } |
909a694e | 926 | |
6d4e81ed | 927 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
928 | } |
929 | ||
930 | static void cpufreq_init_policy(struct cpufreq_policy *policy) | |
931 | { | |
6e2c89d1 | 932 | struct cpufreq_governor *gov = NULL; |
e18f1682 SB |
933 | struct cpufreq_policy new_policy; |
934 | int ret = 0; | |
935 | ||
d5b73cd8 | 936 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 937 | |
6e2c89d1 | 938 | /* Update governor of new_policy to the governor used before hotplug */ |
42f91fa1 | 939 | gov = find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu)); |
6e2c89d1 | 940 | if (gov) |
941 | pr_debug("Restoring governor %s for cpu %d\n", | |
942 | policy->governor->name, policy->cpu); | |
943 | else | |
944 | gov = CPUFREQ_DEFAULT_GOVERNOR; | |
945 | ||
946 | new_policy.governor = gov; | |
947 | ||
a27a9ab7 JB |
948 | /* Use the default policy if its valid. */ |
949 | if (cpufreq_driver->setpolicy) | |
6e2c89d1 | 950 | cpufreq_parse_governor(gov->name, &new_policy.policy, NULL); |
ecf7e461 DJ |
951 | |
952 | /* set default policy */ | |
037ce839 | 953 | ret = cpufreq_set_policy(policy, &new_policy); |
ecf7e461 | 954 | if (ret) { |
2d06d8c4 | 955 | pr_debug("setting policy failed\n"); |
1c3d85dd RW |
956 | if (cpufreq_driver->exit) |
957 | cpufreq_driver->exit(policy); | |
ecf7e461 | 958 | } |
909a694e DJ |
959 | } |
960 | ||
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 | 997 | } |
1da177e4 | 998 | |
8414809c SB |
999 | static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu) |
1000 | { | |
1001 | struct cpufreq_policy *policy; | |
1002 | unsigned long flags; | |
1003 | ||
44871c9c | 1004 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
8414809c SB |
1005 | |
1006 | policy = per_cpu(cpufreq_cpu_data_fallback, cpu); | |
1007 | ||
44871c9c | 1008 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
8414809c | 1009 | |
09712f55 GU |
1010 | if (policy) |
1011 | policy->governor = NULL; | |
6e2c89d1 | 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 | ||
1bfb425b VK |
1076 | static int update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu, |
1077 | struct device *cpu_dev) | |
0d66b91e | 1078 | { |
1bfb425b VK |
1079 | int ret; |
1080 | ||
99ec899e | 1081 | if (WARN_ON(cpu == policy->cpu)) |
1bfb425b VK |
1082 | return 0; |
1083 | ||
1084 | /* Move kobject to the new policy->cpu */ | |
1085 | ret = kobject_move(&policy->kobj, &cpu_dev->kobj); | |
1086 | if (ret) { | |
1087 | pr_err("%s: Failed to move kobj: %d\n", __func__, ret); | |
1088 | return ret; | |
1089 | } | |
cb38ed5c | 1090 | |
ad7722da | 1091 | down_write(&policy->rwsem); |
8efd5765 | 1092 | |
0d66b91e SB |
1093 | policy->last_cpu = policy->cpu; |
1094 | policy->cpu = cpu; | |
1095 | ||
ad7722da | 1096 | up_write(&policy->rwsem); |
8efd5765 | 1097 | |
0d66b91e SB |
1098 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1099 | CPUFREQ_UPDATE_POLICY_CPU, policy); | |
1bfb425b VK |
1100 | |
1101 | return 0; | |
0d66b91e SB |
1102 | } |
1103 | ||
96bbbe4a | 1104 | static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) |
1da177e4 | 1105 | { |
fcf80582 | 1106 | unsigned int j, cpu = dev->id; |
65922465 | 1107 | int ret = -ENOMEM; |
22a7cfb0 | 1108 | struct cpufreq_policy *policy, *tpolicy; |
1da177e4 | 1109 | unsigned long flags; |
96bbbe4a | 1110 | bool recover_policy = cpufreq_suspended; |
1da177e4 | 1111 | |
c32b6b8e AR |
1112 | if (cpu_is_offline(cpu)) |
1113 | return 0; | |
1114 | ||
2d06d8c4 | 1115 | pr_debug("adding CPU %u\n", cpu); |
1da177e4 | 1116 | |
1da177e4 LT |
1117 | /* check whether a different CPU already registered this |
1118 | * CPU because it is in the same boat. */ | |
1119 | policy = cpufreq_cpu_get(cpu); | |
1120 | if (unlikely(policy)) { | |
8ff69732 | 1121 | cpufreq_cpu_put(policy); |
1da177e4 LT |
1122 | return 0; |
1123 | } | |
fcf80582 | 1124 | |
6eed9404 VK |
1125 | if (!down_read_trylock(&cpufreq_rwsem)) |
1126 | return 0; | |
1127 | ||
fcf80582 | 1128 | /* Check if this cpu was hot-unplugged earlier and has siblings */ |
0d1857a1 | 1129 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1b274294 VK |
1130 | list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) { |
1131 | if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) { | |
0d1857a1 | 1132 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
42f921a6 | 1133 | ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev); |
6eed9404 VK |
1134 | up_read(&cpufreq_rwsem); |
1135 | return ret; | |
2eaa3e2d | 1136 | } |
fcf80582 | 1137 | } |
0d1857a1 | 1138 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1139 | |
72368d12 RW |
1140 | /* |
1141 | * Restore the saved policy when doing light-weight init and fall back | |
1142 | * to the full init if that fails. | |
1143 | */ | |
96bbbe4a | 1144 | policy = recover_policy ? cpufreq_policy_restore(cpu) : NULL; |
72368d12 | 1145 | if (!policy) { |
96bbbe4a | 1146 | recover_policy = false; |
8414809c | 1147 | policy = cpufreq_policy_alloc(); |
72368d12 RW |
1148 | if (!policy) |
1149 | goto nomem_out; | |
1150 | } | |
0d66b91e SB |
1151 | |
1152 | /* | |
1153 | * In the resume path, since we restore a saved policy, the assignment | |
1154 | * to policy->cpu is like an update of the existing policy, rather than | |
1155 | * the creation of a brand new one. So we need to perform this update | |
1156 | * by invoking update_policy_cpu(). | |
1157 | */ | |
1bfb425b VK |
1158 | if (recover_policy && cpu != policy->cpu) |
1159 | WARN_ON(update_policy_cpu(policy, cpu, dev)); | |
1160 | else | |
0d66b91e SB |
1161 | policy->cpu = cpu; |
1162 | ||
835481d9 | 1163 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1164 | |
1da177e4 | 1165 | init_completion(&policy->kobj_unregister); |
65f27f38 | 1166 | INIT_WORK(&policy->update, handle_update); |
1da177e4 LT |
1167 | |
1168 | /* call driver. From then on the cpufreq must be able | |
1169 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1170 | */ | |
1c3d85dd | 1171 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1172 | if (ret) { |
2d06d8c4 | 1173 | pr_debug("initialization failed\n"); |
2eaa3e2d | 1174 | goto err_set_policy_cpu; |
1da177e4 | 1175 | } |
643ae6e8 | 1176 | |
6d4e81ed TV |
1177 | down_write(&policy->rwsem); |
1178 | ||
5a7e56a5 VK |
1179 | /* related cpus should atleast have policy->cpus */ |
1180 | cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); | |
1181 | ||
1182 | /* | |
1183 | * affected cpus must always be the one, which are online. We aren't | |
1184 | * managing offline cpus here. | |
1185 | */ | |
1186 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1187 | ||
96bbbe4a | 1188 | if (!recover_policy) { |
5a7e56a5 VK |
1189 | policy->user_policy.min = policy->min; |
1190 | policy->user_policy.max = policy->max; | |
6d4e81ed TV |
1191 | |
1192 | /* prepare interface data */ | |
1193 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, | |
1194 | &dev->kobj, "cpufreq"); | |
1195 | if (ret) { | |
1196 | pr_err("%s: failed to init policy->kobj: %d\n", | |
1197 | __func__, ret); | |
1198 | goto err_init_policy_kobj; | |
1199 | } | |
5a7e56a5 VK |
1200 | } |
1201 | ||
652ed95d VK |
1202 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1203 | for_each_cpu(j, policy->cpus) | |
1204 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1205 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1206 | ||
2ed99e39 | 1207 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1208 | policy->cur = cpufreq_driver->get(policy->cpu); |
1209 | if (!policy->cur) { | |
1210 | pr_err("%s: ->get() failed\n", __func__); | |
1211 | goto err_get_freq; | |
1212 | } | |
1213 | } | |
1214 | ||
d3916691 VK |
1215 | /* |
1216 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1217 | * frequency table present with cpufreq core. In such cases CPU might be | |
1218 | * unstable if it has to run on that frequency for long duration of time | |
1219 | * and so its better to set it to a frequency which is specified in | |
1220 | * freq-table. This also makes cpufreq stats inconsistent as | |
1221 | * cpufreq-stats would fail to register because current frequency of CPU | |
1222 | * isn't found in freq-table. | |
1223 | * | |
1224 | * Because we don't want this change to effect boot process badly, we go | |
1225 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1226 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1227 | * is initialized to zero). | |
1228 | * | |
1229 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1230 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1231 | * equal to target-freq. | |
1232 | */ | |
1233 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1234 | && has_target()) { | |
1235 | /* Are we running at unknown frequency ? */ | |
1236 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1237 | if (ret == -EINVAL) { | |
1238 | /* Warn user and fix it */ | |
1239 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1240 | __func__, policy->cpu, policy->cur); | |
1241 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1242 | CPUFREQ_RELATION_L); | |
1243 | ||
1244 | /* | |
1245 | * Reaching here after boot in a few seconds may not | |
1246 | * mean that system will remain stable at "unknown" | |
1247 | * frequency for longer duration. Hence, a BUG_ON(). | |
1248 | */ | |
1249 | BUG_ON(ret); | |
1250 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1251 | __func__, policy->cpu, policy->cur); | |
1252 | } | |
1253 | } | |
1254 | ||
a1531acd TR |
1255 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1256 | CPUFREQ_START, policy); | |
1257 | ||
96bbbe4a | 1258 | if (!recover_policy) { |
308b60e7 | 1259 | ret = cpufreq_add_dev_interface(policy, dev); |
a82fab29 SB |
1260 | if (ret) |
1261 | goto err_out_unregister; | |
fcd7af91 VK |
1262 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1263 | CPUFREQ_CREATE_POLICY, policy); | |
a82fab29 | 1264 | } |
8ff69732 | 1265 | |
9515f4d6 VK |
1266 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1267 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1268 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1269 | ||
e18f1682 SB |
1270 | cpufreq_init_policy(policy); |
1271 | ||
96bbbe4a | 1272 | if (!recover_policy) { |
08fd8c1c VK |
1273 | policy->user_policy.policy = policy->policy; |
1274 | policy->user_policy.governor = policy->governor; | |
1275 | } | |
4e97b631 | 1276 | up_write(&policy->rwsem); |
08fd8c1c | 1277 | |
038c5b3e | 1278 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1279 | |
6eed9404 VK |
1280 | up_read(&cpufreq_rwsem); |
1281 | ||
7c45cf31 VK |
1282 | /* Callback for handling stuff after policy is ready */ |
1283 | if (cpufreq_driver->ready) | |
1284 | cpufreq_driver->ready(policy); | |
1285 | ||
2d06d8c4 | 1286 | pr_debug("initialization complete\n"); |
87c32271 | 1287 | |
1da177e4 LT |
1288 | return 0; |
1289 | ||
1da177e4 | 1290 | err_out_unregister: |
652ed95d | 1291 | err_get_freq: |
0d1857a1 | 1292 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
474deff7 | 1293 | for_each_cpu(j, policy->cpus) |
7a6aedfa | 1294 | per_cpu(cpufreq_cpu_data, j) = NULL; |
0d1857a1 | 1295 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1296 | |
6d4e81ed TV |
1297 | if (!recover_policy) { |
1298 | kobject_put(&policy->kobj); | |
1299 | wait_for_completion(&policy->kobj_unregister); | |
1300 | } | |
1301 | err_init_policy_kobj: | |
7106e02b PB |
1302 | up_write(&policy->rwsem); |
1303 | ||
da60ce9f VK |
1304 | if (cpufreq_driver->exit) |
1305 | cpufreq_driver->exit(policy); | |
2eaa3e2d | 1306 | err_set_policy_cpu: |
96bbbe4a | 1307 | if (recover_policy) { |
72368d12 RW |
1308 | /* Do not leave stale fallback data behind. */ |
1309 | per_cpu(cpufreq_cpu_data_fallback, cpu) = NULL; | |
42f921a6 | 1310 | cpufreq_policy_put_kobj(policy); |
72368d12 | 1311 | } |
e9698cc5 | 1312 | cpufreq_policy_free(policy); |
42f921a6 | 1313 | |
1da177e4 | 1314 | nomem_out: |
6eed9404 VK |
1315 | up_read(&cpufreq_rwsem); |
1316 | ||
1da177e4 LT |
1317 | return ret; |
1318 | } | |
1319 | ||
a82fab29 SB |
1320 | /** |
1321 | * cpufreq_add_dev - add a CPU device | |
1322 | * | |
1323 | * Adds the cpufreq interface for a CPU device. | |
1324 | * | |
1325 | * The Oracle says: try running cpufreq registration/unregistration concurrently | |
1326 | * with with cpu hotplugging and all hell will break loose. Tried to clean this | |
1327 | * mess up, but more thorough testing is needed. - Mathieu | |
1328 | */ | |
1329 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1330 | { | |
96bbbe4a | 1331 | return __cpufreq_add_dev(dev, sif); |
a82fab29 SB |
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; |
1bfb425b | 1338 | int 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 | } | |
1da177e4 | 1365 | |
fa69e33f | 1366 | strncpy(per_cpu(cpufreq_cpu_governor, cpu), |
3a3e9e06 | 1367 | policy->governor->name, CPUFREQ_NAME_LEN); |
db5f2995 | 1368 | } |
1da177e4 | 1369 | |
ad7722da | 1370 | down_read(&policy->rwsem); |
3a3e9e06 | 1371 | cpus = cpumask_weight(policy->cpus); |
ad7722da | 1372 | up_read(&policy->rwsem); |
084f3493 | 1373 | |
61173f25 | 1374 | if (cpu != policy->cpu) { |
6964d91d | 1375 | sysfs_remove_link(&dev->kobj, "cpufreq"); |
73bf0fc2 | 1376 | } else if (cpus > 1) { |
1bfb425b VK |
1377 | /* Nominate new CPU */ |
1378 | int new_cpu = cpumask_any_but(policy->cpus, cpu); | |
1379 | struct device *cpu_dev = get_cpu_device(new_cpu); | |
a82fab29 | 1380 | |
1bfb425b VK |
1381 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); |
1382 | ret = update_policy_cpu(policy, new_cpu, cpu_dev); | |
1383 | if (ret) { | |
1384 | if (sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
1385 | "cpufreq")) | |
1386 | pr_err("%s: Failed to restore kobj link to cpu:%d\n", | |
1387 | __func__, cpu_dev->id); | |
1388 | return ret; | |
1da177e4 | 1389 | } |
1bfb425b VK |
1390 | |
1391 | if (!cpufreq_suspended) | |
1392 | pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n", | |
1393 | __func__, new_cpu, cpu); | |
789ca243 | 1394 | } else if (cpufreq_driver->stop_cpu) { |
367dc4aa | 1395 | cpufreq_driver->stop_cpu(policy); |
1da177e4 | 1396 | } |
1da177e4 | 1397 | |
cedb70af SB |
1398 | return 0; |
1399 | } | |
1400 | ||
1401 | static int __cpufreq_remove_dev_finish(struct device *dev, | |
96bbbe4a | 1402 | struct subsys_interface *sif) |
cedb70af SB |
1403 | { |
1404 | unsigned int cpu = dev->id, cpus; | |
1405 | int ret; | |
1406 | unsigned long flags; | |
1407 | struct cpufreq_policy *policy; | |
cedb70af SB |
1408 | |
1409 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1410 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1411 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1412 | ||
1413 | if (!policy) { | |
1414 | pr_debug("%s: No cpu_data found\n", __func__); | |
1415 | return -EINVAL; | |
1416 | } | |
1417 | ||
ad7722da | 1418 | down_write(&policy->rwsem); |
cedb70af | 1419 | cpus = cpumask_weight(policy->cpus); |
9c8f1ee4 VK |
1420 | |
1421 | if (cpus > 1) | |
1422 | cpumask_clear_cpu(cpu, policy->cpus); | |
ad7722da | 1423 | up_write(&policy->rwsem); |
cedb70af | 1424 | |
b8eed8af VK |
1425 | /* If cpu is last user of policy, free policy */ |
1426 | if (cpus == 1) { | |
9c0ebcf7 | 1427 | if (has_target()) { |
3de9bdeb VK |
1428 | ret = __cpufreq_governor(policy, |
1429 | CPUFREQ_GOV_POLICY_EXIT); | |
1430 | if (ret) { | |
1431 | pr_err("%s: Failed to exit governor\n", | |
e837f9b5 | 1432 | __func__); |
3de9bdeb VK |
1433 | return ret; |
1434 | } | |
edab2fbc | 1435 | } |
2a998599 | 1436 | |
96bbbe4a | 1437 | if (!cpufreq_suspended) |
42f921a6 | 1438 | cpufreq_policy_put_kobj(policy); |
7d26e2d5 | 1439 | |
8414809c SB |
1440 | /* |
1441 | * Perform the ->exit() even during light-weight tear-down, | |
1442 | * since this is a core component, and is essential for the | |
1443 | * subsequent light-weight ->init() to succeed. | |
b8eed8af | 1444 | */ |
1c3d85dd | 1445 | if (cpufreq_driver->exit) |
3a3e9e06 | 1446 | cpufreq_driver->exit(policy); |
27ecddc2 | 1447 | |
9515f4d6 VK |
1448 | /* Remove policy from list of active policies */ |
1449 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1450 | list_del(&policy->policy_list); | |
1451 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1452 | ||
96bbbe4a | 1453 | if (!cpufreq_suspended) |
3a3e9e06 | 1454 | cpufreq_policy_free(policy); |
e5c87b76 SK |
1455 | } else if (has_target()) { |
1456 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
1457 | if (!ret) | |
1458 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1459 | ||
1460 | if (ret) { | |
1461 | pr_err("%s: Failed to start governor\n", __func__); | |
1462 | return ret; | |
2a998599 | 1463 | } |
27ecddc2 | 1464 | } |
1da177e4 | 1465 | |
474deff7 | 1466 | per_cpu(cpufreq_cpu_data, cpu) = NULL; |
1da177e4 LT |
1467 | return 0; |
1468 | } | |
1469 | ||
cedb70af | 1470 | /** |
27a862e9 | 1471 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1472 | * |
1473 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1474 | */ |
8a25a2fd | 1475 | static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1476 | { |
8a25a2fd | 1477 | unsigned int cpu = dev->id; |
27a862e9 | 1478 | int ret; |
ec28297a VP |
1479 | |
1480 | if (cpu_is_offline(cpu)) | |
1481 | return 0; | |
1482 | ||
96bbbe4a | 1483 | ret = __cpufreq_remove_dev_prepare(dev, sif); |
27a862e9 VK |
1484 | |
1485 | if (!ret) | |
96bbbe4a | 1486 | ret = __cpufreq_remove_dev_finish(dev, sif); |
27a862e9 VK |
1487 | |
1488 | return ret; | |
5a01f2e8 VP |
1489 | } |
1490 | ||
65f27f38 | 1491 | static void handle_update(struct work_struct *work) |
1da177e4 | 1492 | { |
65f27f38 DH |
1493 | struct cpufreq_policy *policy = |
1494 | container_of(work, struct cpufreq_policy, update); | |
1495 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1496 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1497 | cpufreq_update_policy(cpu); |
1498 | } | |
1499 | ||
1500 | /** | |
bb176f7d VK |
1501 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1502 | * in deep trouble. | |
a1e1dc41 | 1503 | * @policy: policy managing CPUs |
1da177e4 LT |
1504 | * @new_freq: CPU frequency the CPU actually runs at |
1505 | * | |
29464f28 DJ |
1506 | * We adjust to current frequency first, and need to clean up later. |
1507 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1508 | */ |
a1e1dc41 | 1509 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1510 | unsigned int new_freq) |
1da177e4 LT |
1511 | { |
1512 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1513 | |
e837f9b5 | 1514 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1515 | policy->cur, new_freq); |
1da177e4 | 1516 | |
a1e1dc41 | 1517 | freqs.old = policy->cur; |
1da177e4 | 1518 | freqs.new = new_freq; |
b43a7ffb | 1519 | |
8fec051e VK |
1520 | cpufreq_freq_transition_begin(policy, &freqs); |
1521 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1522 | } |
1523 | ||
32ee8c3e | 1524 | /** |
4ab70df4 | 1525 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1526 | * @cpu: CPU number |
1527 | * | |
1528 | * This is the last known freq, without actually getting it from the driver. | |
1529 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1530 | */ | |
1531 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1532 | { | |
9e21ba8b | 1533 | struct cpufreq_policy *policy; |
e08f5f5b | 1534 | unsigned int ret_freq = 0; |
95235ca2 | 1535 | |
1c3d85dd RW |
1536 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1537 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1538 | |
1539 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1540 | if (policy) { |
e08f5f5b | 1541 | ret_freq = policy->cur; |
95235ca2 VP |
1542 | cpufreq_cpu_put(policy); |
1543 | } | |
1544 | ||
4d34a67d | 1545 | return ret_freq; |
95235ca2 VP |
1546 | } |
1547 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1548 | ||
3d737108 JB |
1549 | /** |
1550 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1551 | * @cpu: CPU number | |
1552 | * | |
1553 | * Just return the max possible frequency for a given CPU. | |
1554 | */ | |
1555 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1556 | { | |
1557 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1558 | unsigned int ret_freq = 0; | |
1559 | ||
1560 | if (policy) { | |
1561 | ret_freq = policy->max; | |
1562 | cpufreq_cpu_put(policy); | |
1563 | } | |
1564 | ||
1565 | return ret_freq; | |
1566 | } | |
1567 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1568 | ||
d92d50a4 | 1569 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1570 | { |
e08f5f5b | 1571 | unsigned int ret_freq = 0; |
5800043b | 1572 | |
1c3d85dd | 1573 | if (!cpufreq_driver->get) |
4d34a67d | 1574 | return ret_freq; |
1da177e4 | 1575 | |
d92d50a4 | 1576 | ret_freq = cpufreq_driver->get(policy->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)) { | |
a1e1dc41 | 1583 | cpufreq_out_of_sync(policy, 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); | |
d92d50a4 | 1604 | ret_freq = __cpufreq_get(policy); |
999976e0 | 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 | 1662 | if (!has_target()) |
b1b12bab | 1663 | goto suspend; |
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 | 1675 | } |
b1b12bab VK |
1676 | |
1677 | suspend: | |
1678 | cpufreq_suspended = true; | |
42d4dc3f BH |
1679 | } |
1680 | ||
1da177e4 | 1681 | /** |
2f0aea93 | 1682 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1683 | * |
2f0aea93 VK |
1684 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1685 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1686 | */ |
2f0aea93 | 1687 | void cpufreq_resume(void) |
1da177e4 | 1688 | { |
3a3e9e06 | 1689 | struct cpufreq_policy *policy; |
1da177e4 | 1690 | |
2f0aea93 VK |
1691 | if (!cpufreq_driver) |
1692 | return; | |
1da177e4 | 1693 | |
8e30444e LT |
1694 | cpufreq_suspended = false; |
1695 | ||
2f0aea93 | 1696 | if (!has_target()) |
e00e56df | 1697 | return; |
1da177e4 | 1698 | |
2f0aea93 | 1699 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1700 | |
2f0aea93 | 1701 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { |
0c5aa405 VK |
1702 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) |
1703 | pr_err("%s: Failed to resume driver: %p\n", __func__, | |
1704 | policy); | |
1705 | else if (__cpufreq_governor(policy, CPUFREQ_GOV_START) | |
2f0aea93 VK |
1706 | || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS)) |
1707 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1708 | __func__, policy); | |
1da177e4 | 1709 | |
2f0aea93 VK |
1710 | /* |
1711 | * schedule call cpufreq_update_policy() for boot CPU, i.e. last | |
1712 | * policy in list. It will verify that the current freq is in | |
1713 | * sync with what we believe it to be. | |
1714 | */ | |
1715 | if (list_is_last(&policy->policy_list, &cpufreq_policy_list)) | |
1716 | schedule_work(&policy->update); | |
1717 | } | |
1718 | } | |
1da177e4 | 1719 | |
9d95046e BP |
1720 | /** |
1721 | * cpufreq_get_current_driver - return current driver's name | |
1722 | * | |
1723 | * Return the name string of the currently loaded cpufreq driver | |
1724 | * or NULL, if none. | |
1725 | */ | |
1726 | const char *cpufreq_get_current_driver(void) | |
1727 | { | |
1c3d85dd RW |
1728 | if (cpufreq_driver) |
1729 | return cpufreq_driver->name; | |
1730 | ||
1731 | return NULL; | |
9d95046e BP |
1732 | } |
1733 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1734 | |
51315cdf TP |
1735 | /** |
1736 | * cpufreq_get_driver_data - return current driver data | |
1737 | * | |
1738 | * Return the private data of the currently loaded cpufreq | |
1739 | * driver, or NULL if no cpufreq driver is loaded. | |
1740 | */ | |
1741 | void *cpufreq_get_driver_data(void) | |
1742 | { | |
1743 | if (cpufreq_driver) | |
1744 | return cpufreq_driver->driver_data; | |
1745 | ||
1746 | return NULL; | |
1747 | } | |
1748 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1749 | ||
1da177e4 LT |
1750 | /********************************************************************* |
1751 | * NOTIFIER LISTS INTERFACE * | |
1752 | *********************************************************************/ | |
1753 | ||
1754 | /** | |
1755 | * cpufreq_register_notifier - register a driver with cpufreq | |
1756 | * @nb: notifier function to register | |
1757 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1758 | * | |
32ee8c3e | 1759 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1760 | * are notified about clock rate changes (once before and once after |
1761 | * the transition), or a list of drivers that are notified about | |
1762 | * changes in cpufreq policy. | |
1763 | * | |
1764 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1765 | * blocking_notifier_chain_register. |
1da177e4 LT |
1766 | */ |
1767 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1768 | { | |
1769 | int ret; | |
1770 | ||
d5aaffa9 DB |
1771 | if (cpufreq_disabled()) |
1772 | return -EINVAL; | |
1773 | ||
74212ca4 CEB |
1774 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1775 | ||
1da177e4 LT |
1776 | switch (list) { |
1777 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1778 | ret = srcu_notifier_chain_register( |
e041c683 | 1779 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1780 | break; |
1781 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1782 | ret = blocking_notifier_chain_register( |
1783 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1784 | break; |
1785 | default: | |
1786 | ret = -EINVAL; | |
1787 | } | |
1da177e4 LT |
1788 | |
1789 | return ret; | |
1790 | } | |
1791 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1792 | ||
1da177e4 LT |
1793 | /** |
1794 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1795 | * @nb: notifier block to be unregistered | |
bb176f7d | 1796 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1797 | * |
1798 | * Remove a driver from the CPU frequency notifier list. | |
1799 | * | |
1800 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1801 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1802 | */ |
1803 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1804 | { | |
1805 | int ret; | |
1806 | ||
d5aaffa9 DB |
1807 | if (cpufreq_disabled()) |
1808 | return -EINVAL; | |
1809 | ||
1da177e4 LT |
1810 | switch (list) { |
1811 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1812 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1813 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1814 | break; |
1815 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1816 | ret = blocking_notifier_chain_unregister( |
1817 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1818 | break; |
1819 | default: | |
1820 | ret = -EINVAL; | |
1821 | } | |
1da177e4 LT |
1822 | |
1823 | return ret; | |
1824 | } | |
1825 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1826 | ||
1827 | ||
1828 | /********************************************************************* | |
1829 | * GOVERNORS * | |
1830 | *********************************************************************/ | |
1831 | ||
1c03a2d0 VK |
1832 | /* Must set freqs->new to intermediate frequency */ |
1833 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1834 | struct cpufreq_freqs *freqs, int index) | |
1835 | { | |
1836 | int ret; | |
1837 | ||
1838 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1839 | ||
1840 | /* We don't need to switch to intermediate freq */ | |
1841 | if (!freqs->new) | |
1842 | return 0; | |
1843 | ||
1844 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1845 | __func__, policy->cpu, freqs->old, freqs->new); | |
1846 | ||
1847 | cpufreq_freq_transition_begin(policy, freqs); | |
1848 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1849 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1850 | ||
1851 | if (ret) | |
1852 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1853 | __func__, ret); | |
1854 | ||
1855 | return ret; | |
1856 | } | |
1857 | ||
8d65775d VK |
1858 | static int __target_index(struct cpufreq_policy *policy, |
1859 | struct cpufreq_frequency_table *freq_table, int index) | |
1860 | { | |
1c03a2d0 VK |
1861 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1862 | unsigned int intermediate_freq = 0; | |
8d65775d VK |
1863 | int retval = -EINVAL; |
1864 | bool notify; | |
1865 | ||
1866 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
8d65775d | 1867 | if (notify) { |
1c03a2d0 VK |
1868 | /* Handle switching to intermediate frequency */ |
1869 | if (cpufreq_driver->get_intermediate) { | |
1870 | retval = __target_intermediate(policy, &freqs, index); | |
1871 | if (retval) | |
1872 | return retval; | |
1873 | ||
1874 | intermediate_freq = freqs.new; | |
1875 | /* Set old freq to intermediate */ | |
1876 | if (intermediate_freq) | |
1877 | freqs.old = freqs.new; | |
1878 | } | |
8d65775d | 1879 | |
1c03a2d0 | 1880 | freqs.new = freq_table[index].frequency; |
8d65775d VK |
1881 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1882 | __func__, policy->cpu, freqs.old, freqs.new); | |
1883 | ||
1884 | cpufreq_freq_transition_begin(policy, &freqs); | |
1885 | } | |
1886 | ||
1887 | retval = cpufreq_driver->target_index(policy, index); | |
1888 | if (retval) | |
1889 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1890 | retval); | |
1891 | ||
1c03a2d0 | 1892 | if (notify) { |
8d65775d VK |
1893 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1894 | ||
1c03a2d0 VK |
1895 | /* |
1896 | * Failed after setting to intermediate freq? Driver should have | |
1897 | * reverted back to initial frequency and so should we. Check | |
1898 | * here for intermediate_freq instead of get_intermediate, in | |
1899 | * case we have't switched to intermediate freq at all. | |
1900 | */ | |
1901 | if (unlikely(retval && intermediate_freq)) { | |
1902 | freqs.old = intermediate_freq; | |
1903 | freqs.new = policy->restore_freq; | |
1904 | cpufreq_freq_transition_begin(policy, &freqs); | |
1905 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1906 | } | |
1907 | } | |
1908 | ||
8d65775d VK |
1909 | return retval; |
1910 | } | |
1911 | ||
1da177e4 LT |
1912 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1913 | unsigned int target_freq, | |
1914 | unsigned int relation) | |
1915 | { | |
7249924e | 1916 | unsigned int old_target_freq = target_freq; |
8d65775d | 1917 | int retval = -EINVAL; |
c32b6b8e | 1918 | |
a7b422cd KRW |
1919 | if (cpufreq_disabled()) |
1920 | return -ENODEV; | |
1921 | ||
7249924e VK |
1922 | /* Make sure that target_freq is within supported range */ |
1923 | if (target_freq > policy->max) | |
1924 | target_freq = policy->max; | |
1925 | if (target_freq < policy->min) | |
1926 | target_freq = policy->min; | |
1927 | ||
1928 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1929 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1930 | |
9c0ebcf7 VK |
1931 | /* |
1932 | * This might look like a redundant call as we are checking it again | |
1933 | * after finding index. But it is left intentionally for cases where | |
1934 | * exactly same freq is called again and so we can save on few function | |
1935 | * calls. | |
1936 | */ | |
5a1c0228 VK |
1937 | if (target_freq == policy->cur) |
1938 | return 0; | |
1939 | ||
1c03a2d0 VK |
1940 | /* Save last value to restore later on errors */ |
1941 | policy->restore_freq = policy->cur; | |
1942 | ||
1c3d85dd RW |
1943 | if (cpufreq_driver->target) |
1944 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
9c0ebcf7 VK |
1945 | else if (cpufreq_driver->target_index) { |
1946 | struct cpufreq_frequency_table *freq_table; | |
1947 | int index; | |
90d45d17 | 1948 | |
9c0ebcf7 VK |
1949 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
1950 | if (unlikely(!freq_table)) { | |
1951 | pr_err("%s: Unable to find freq_table\n", __func__); | |
1952 | goto out; | |
1953 | } | |
1954 | ||
1955 | retval = cpufreq_frequency_table_target(policy, freq_table, | |
1956 | target_freq, relation, &index); | |
1957 | if (unlikely(retval)) { | |
1958 | pr_err("%s: Unable to find matching freq\n", __func__); | |
1959 | goto out; | |
1960 | } | |
1961 | ||
d4019f0a | 1962 | if (freq_table[index].frequency == policy->cur) { |
9c0ebcf7 | 1963 | retval = 0; |
d4019f0a VK |
1964 | goto out; |
1965 | } | |
1966 | ||
8d65775d | 1967 | retval = __target_index(policy, freq_table, index); |
9c0ebcf7 VK |
1968 | } |
1969 | ||
1970 | out: | |
1da177e4 LT |
1971 | return retval; |
1972 | } | |
1973 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1974 | ||
1da177e4 LT |
1975 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1976 | unsigned int target_freq, | |
1977 | unsigned int relation) | |
1978 | { | |
f1829e4a | 1979 | int ret = -EINVAL; |
1da177e4 | 1980 | |
ad7722da | 1981 | down_write(&policy->rwsem); |
1da177e4 LT |
1982 | |
1983 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1984 | ||
ad7722da | 1985 | up_write(&policy->rwsem); |
1da177e4 | 1986 | |
1da177e4 LT |
1987 | return ret; |
1988 | } | |
1989 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1990 | ||
e08f5f5b GS |
1991 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
1992 | unsigned int event) | |
1da177e4 | 1993 | { |
cc993cab | 1994 | int ret; |
6afde10c TR |
1995 | |
1996 | /* Only must be defined when default governor is known to have latency | |
1997 | restrictions, like e.g. conservative or ondemand. | |
1998 | That this is the case is already ensured in Kconfig | |
1999 | */ | |
2000 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
2001 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
2002 | #else | |
2003 | struct cpufreq_governor *gov = NULL; | |
2004 | #endif | |
1c256245 | 2005 | |
2f0aea93 VK |
2006 | /* Don't start any governor operations if we are entering suspend */ |
2007 | if (cpufreq_suspended) | |
2008 | return 0; | |
cb57720b EZ |
2009 | /* |
2010 | * Governor might not be initiated here if ACPI _PPC changed | |
2011 | * notification happened, so check it. | |
2012 | */ | |
2013 | if (!policy->governor) | |
2014 | return -EINVAL; | |
2f0aea93 | 2015 | |
1c256245 TR |
2016 | if (policy->governor->max_transition_latency && |
2017 | policy->cpuinfo.transition_latency > | |
2018 | policy->governor->max_transition_latency) { | |
6afde10c TR |
2019 | if (!gov) |
2020 | return -EINVAL; | |
2021 | else { | |
e837f9b5 JP |
2022 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
2023 | policy->governor->name, gov->name); | |
6afde10c TR |
2024 | policy->governor = gov; |
2025 | } | |
1c256245 | 2026 | } |
1da177e4 | 2027 | |
fe492f3f VK |
2028 | if (event == CPUFREQ_GOV_POLICY_INIT) |
2029 | if (!try_module_get(policy->governor->owner)) | |
2030 | return -EINVAL; | |
1da177e4 | 2031 | |
2d06d8c4 | 2032 | pr_debug("__cpufreq_governor for CPU %u, event %u\n", |
e837f9b5 | 2033 | policy->cpu, event); |
95731ebb XC |
2034 | |
2035 | mutex_lock(&cpufreq_governor_lock); | |
56d07db2 | 2036 | if ((policy->governor_enabled && event == CPUFREQ_GOV_START) |
f73d3933 VK |
2037 | || (!policy->governor_enabled |
2038 | && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) { | |
95731ebb XC |
2039 | mutex_unlock(&cpufreq_governor_lock); |
2040 | return -EBUSY; | |
2041 | } | |
2042 | ||
2043 | if (event == CPUFREQ_GOV_STOP) | |
2044 | policy->governor_enabled = false; | |
2045 | else if (event == CPUFREQ_GOV_START) | |
2046 | policy->governor_enabled = true; | |
2047 | ||
2048 | mutex_unlock(&cpufreq_governor_lock); | |
2049 | ||
1da177e4 LT |
2050 | ret = policy->governor->governor(policy, event); |
2051 | ||
4d5dcc42 VK |
2052 | if (!ret) { |
2053 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
2054 | policy->governor->initialized++; | |
2055 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
2056 | policy->governor->initialized--; | |
95731ebb XC |
2057 | } else { |
2058 | /* Restore original values */ | |
2059 | mutex_lock(&cpufreq_governor_lock); | |
2060 | if (event == CPUFREQ_GOV_STOP) | |
2061 | policy->governor_enabled = true; | |
2062 | else if (event == CPUFREQ_GOV_START) | |
2063 | policy->governor_enabled = false; | |
2064 | mutex_unlock(&cpufreq_governor_lock); | |
4d5dcc42 | 2065 | } |
b394058f | 2066 | |
fe492f3f VK |
2067 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
2068 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
2069 | module_put(policy->governor->owner); |
2070 | ||
2071 | return ret; | |
2072 | } | |
2073 | ||
1da177e4 LT |
2074 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2075 | { | |
3bcb09a3 | 2076 | int err; |
1da177e4 LT |
2077 | |
2078 | if (!governor) | |
2079 | return -EINVAL; | |
2080 | ||
a7b422cd KRW |
2081 | if (cpufreq_disabled()) |
2082 | return -ENODEV; | |
2083 | ||
3fc54d37 | 2084 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2085 | |
b394058f | 2086 | governor->initialized = 0; |
3bcb09a3 | 2087 | err = -EBUSY; |
42f91fa1 | 2088 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2089 | err = 0; |
2090 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2091 | } |
1da177e4 | 2092 | |
32ee8c3e | 2093 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2094 | return err; |
1da177e4 LT |
2095 | } |
2096 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2097 | ||
1da177e4 LT |
2098 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2099 | { | |
90e41bac | 2100 | int cpu; |
90e41bac | 2101 | |
1da177e4 LT |
2102 | if (!governor) |
2103 | return; | |
2104 | ||
a7b422cd KRW |
2105 | if (cpufreq_disabled()) |
2106 | return; | |
2107 | ||
90e41bac PB |
2108 | for_each_present_cpu(cpu) { |
2109 | if (cpu_online(cpu)) | |
2110 | continue; | |
2111 | if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name)) | |
2112 | strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0"); | |
2113 | } | |
90e41bac | 2114 | |
3fc54d37 | 2115 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2116 | list_del(&governor->governor_list); |
3fc54d37 | 2117 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2118 | return; |
2119 | } | |
2120 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2121 | ||
2122 | ||
1da177e4 LT |
2123 | /********************************************************************* |
2124 | * POLICY INTERFACE * | |
2125 | *********************************************************************/ | |
2126 | ||
2127 | /** | |
2128 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2129 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2130 | * is written | |
1da177e4 LT |
2131 | * |
2132 | * Reads the current cpufreq policy. | |
2133 | */ | |
2134 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2135 | { | |
2136 | struct cpufreq_policy *cpu_policy; | |
2137 | if (!policy) | |
2138 | return -EINVAL; | |
2139 | ||
2140 | cpu_policy = cpufreq_cpu_get(cpu); | |
2141 | if (!cpu_policy) | |
2142 | return -EINVAL; | |
2143 | ||
d5b73cd8 | 2144 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2145 | |
2146 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2147 | return 0; |
2148 | } | |
2149 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2150 | ||
153d7f3f | 2151 | /* |
037ce839 VK |
2152 | * policy : current policy. |
2153 | * new_policy: policy to be set. | |
153d7f3f | 2154 | */ |
037ce839 | 2155 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2156 | struct cpufreq_policy *new_policy) |
1da177e4 | 2157 | { |
d9a789c7 RW |
2158 | struct cpufreq_governor *old_gov; |
2159 | int ret; | |
1da177e4 | 2160 | |
e837f9b5 JP |
2161 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2162 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2163 | |
d5b73cd8 | 2164 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2165 | |
d9a789c7 RW |
2166 | if (new_policy->min > policy->max || new_policy->max < policy->min) |
2167 | return -EINVAL; | |
9c9a43ed | 2168 | |
1da177e4 | 2169 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2170 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2171 | if (ret) |
d9a789c7 | 2172 | return ret; |
1da177e4 | 2173 | |
1da177e4 | 2174 | /* adjust if necessary - all reasons */ |
e041c683 | 2175 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2176 | CPUFREQ_ADJUST, new_policy); |
1da177e4 LT |
2177 | |
2178 | /* adjust if necessary - hardware incompatibility*/ | |
e041c683 | 2179 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2180 | CPUFREQ_INCOMPATIBLE, new_policy); |
1da177e4 | 2181 | |
bb176f7d VK |
2182 | /* |
2183 | * verify the cpu speed can be set within this limit, which might be | |
2184 | * different to the first one | |
2185 | */ | |
3a3e9e06 | 2186 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2187 | if (ret) |
d9a789c7 | 2188 | return ret; |
1da177e4 LT |
2189 | |
2190 | /* notification of the new policy */ | |
e041c683 | 2191 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2192 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2193 | |
3a3e9e06 VK |
2194 | policy->min = new_policy->min; |
2195 | policy->max = new_policy->max; | |
1da177e4 | 2196 | |
2d06d8c4 | 2197 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2198 | policy->min, policy->max); |
1da177e4 | 2199 | |
1c3d85dd | 2200 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2201 | policy->policy = new_policy->policy; |
2d06d8c4 | 2202 | pr_debug("setting range\n"); |
d9a789c7 RW |
2203 | return cpufreq_driver->setpolicy(new_policy); |
2204 | } | |
1da177e4 | 2205 | |
d9a789c7 RW |
2206 | if (new_policy->governor == policy->governor) |
2207 | goto out; | |
7bd353a9 | 2208 | |
d9a789c7 RW |
2209 | pr_debug("governor switch\n"); |
2210 | ||
2211 | /* save old, working values */ | |
2212 | old_gov = policy->governor; | |
2213 | /* end old governor */ | |
2214 | if (old_gov) { | |
2215 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
2216 | up_write(&policy->rwsem); | |
e5c87b76 | 2217 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
d9a789c7 | 2218 | down_write(&policy->rwsem); |
1da177e4 LT |
2219 | } |
2220 | ||
d9a789c7 RW |
2221 | /* start new governor */ |
2222 | policy->governor = new_policy->governor; | |
2223 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) { | |
2224 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_START)) | |
2225 | goto out; | |
2226 | ||
2227 | up_write(&policy->rwsem); | |
2228 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
2229 | down_write(&policy->rwsem); | |
2230 | } | |
2231 | ||
2232 | /* new governor failed, so re-start old one */ | |
2233 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2234 | if (old_gov) { | |
2235 | policy->governor = old_gov; | |
2236 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); | |
2237 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
2238 | } | |
2239 | ||
2240 | return -EINVAL; | |
2241 | ||
2242 | out: | |
2243 | pr_debug("governor: change or update limits\n"); | |
2244 | return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1da177e4 LT |
2245 | } |
2246 | ||
1da177e4 LT |
2247 | /** |
2248 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2249 | * @cpu: CPU which shall be re-evaluated | |
2250 | * | |
25985edc | 2251 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2252 | * at different times. |
2253 | */ | |
2254 | int cpufreq_update_policy(unsigned int cpu) | |
2255 | { | |
3a3e9e06 VK |
2256 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2257 | struct cpufreq_policy new_policy; | |
f1829e4a | 2258 | int ret; |
1da177e4 | 2259 | |
fefa8ff8 AP |
2260 | if (!policy) |
2261 | return -ENODEV; | |
1da177e4 | 2262 | |
ad7722da | 2263 | down_write(&policy->rwsem); |
1da177e4 | 2264 | |
2d06d8c4 | 2265 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2266 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2267 | new_policy.min = policy->user_policy.min; |
2268 | new_policy.max = policy->user_policy.max; | |
2269 | new_policy.policy = policy->user_policy.policy; | |
2270 | new_policy.governor = policy->user_policy.governor; | |
1da177e4 | 2271 | |
bb176f7d VK |
2272 | /* |
2273 | * BIOS might change freq behind our back | |
2274 | * -> ask driver for current freq and notify governors about a change | |
2275 | */ | |
2ed99e39 | 2276 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
3a3e9e06 | 2277 | new_policy.cur = cpufreq_driver->get(cpu); |
bd0fa9bb VK |
2278 | if (WARN_ON(!new_policy.cur)) { |
2279 | ret = -EIO; | |
fefa8ff8 | 2280 | goto unlock; |
bd0fa9bb VK |
2281 | } |
2282 | ||
3a3e9e06 | 2283 | if (!policy->cur) { |
e837f9b5 | 2284 | pr_debug("Driver did not initialize current freq\n"); |
3a3e9e06 | 2285 | policy->cur = new_policy.cur; |
a85f7bd3 | 2286 | } else { |
9c0ebcf7 | 2287 | if (policy->cur != new_policy.cur && has_target()) |
a1e1dc41 | 2288 | cpufreq_out_of_sync(policy, new_policy.cur); |
a85f7bd3 | 2289 | } |
0961dd0d TR |
2290 | } |
2291 | ||
037ce839 | 2292 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2293 | |
fefa8ff8 | 2294 | unlock: |
ad7722da | 2295 | up_write(&policy->rwsem); |
5a01f2e8 | 2296 | |
3a3e9e06 | 2297 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2298 | return ret; |
2299 | } | |
2300 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2301 | ||
2760984f | 2302 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2303 | unsigned long action, void *hcpu) |
2304 | { | |
2305 | unsigned int cpu = (unsigned long)hcpu; | |
8a25a2fd | 2306 | struct device *dev; |
c32b6b8e | 2307 | |
8a25a2fd KS |
2308 | dev = get_cpu_device(cpu); |
2309 | if (dev) { | |
5302c3fb | 2310 | switch (action & ~CPU_TASKS_FROZEN) { |
c32b6b8e | 2311 | case CPU_ONLINE: |
96bbbe4a | 2312 | __cpufreq_add_dev(dev, NULL); |
c32b6b8e | 2313 | break; |
5302c3fb | 2314 | |
c32b6b8e | 2315 | case CPU_DOWN_PREPARE: |
96bbbe4a | 2316 | __cpufreq_remove_dev_prepare(dev, NULL); |
1aee40ac SB |
2317 | break; |
2318 | ||
2319 | case CPU_POST_DEAD: | |
96bbbe4a | 2320 | __cpufreq_remove_dev_finish(dev, NULL); |
c32b6b8e | 2321 | break; |
5302c3fb | 2322 | |
5a01f2e8 | 2323 | case CPU_DOWN_FAILED: |
96bbbe4a | 2324 | __cpufreq_add_dev(dev, NULL); |
c32b6b8e AR |
2325 | break; |
2326 | } | |
2327 | } | |
2328 | return NOTIFY_OK; | |
2329 | } | |
2330 | ||
9c36f746 | 2331 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2332 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2333 | }; |
1da177e4 | 2334 | |
6f19efc0 LM |
2335 | /********************************************************************* |
2336 | * BOOST * | |
2337 | *********************************************************************/ | |
2338 | static int cpufreq_boost_set_sw(int state) | |
2339 | { | |
2340 | struct cpufreq_frequency_table *freq_table; | |
2341 | struct cpufreq_policy *policy; | |
2342 | int ret = -EINVAL; | |
2343 | ||
2344 | list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { | |
2345 | freq_table = cpufreq_frequency_get_table(policy->cpu); | |
2346 | if (freq_table) { | |
2347 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2348 | freq_table); | |
2349 | if (ret) { | |
2350 | pr_err("%s: Policy frequency update failed\n", | |
2351 | __func__); | |
2352 | break; | |
2353 | } | |
2354 | policy->user_policy.max = policy->max; | |
2355 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2356 | } | |
2357 | } | |
2358 | ||
2359 | return ret; | |
2360 | } | |
2361 | ||
2362 | int cpufreq_boost_trigger_state(int state) | |
2363 | { | |
2364 | unsigned long flags; | |
2365 | int ret = 0; | |
2366 | ||
2367 | if (cpufreq_driver->boost_enabled == state) | |
2368 | return 0; | |
2369 | ||
2370 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2371 | cpufreq_driver->boost_enabled = state; | |
2372 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2373 | ||
2374 | ret = cpufreq_driver->set_boost(state); | |
2375 | if (ret) { | |
2376 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2377 | cpufreq_driver->boost_enabled = !state; | |
2378 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2379 | ||
e837f9b5 JP |
2380 | pr_err("%s: Cannot %s BOOST\n", |
2381 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2382 | } |
2383 | ||
2384 | return ret; | |
2385 | } | |
2386 | ||
2387 | int cpufreq_boost_supported(void) | |
2388 | { | |
2389 | if (likely(cpufreq_driver)) | |
2390 | return cpufreq_driver->boost_supported; | |
2391 | ||
2392 | return 0; | |
2393 | } | |
2394 | EXPORT_SYMBOL_GPL(cpufreq_boost_supported); | |
2395 | ||
2396 | int cpufreq_boost_enabled(void) | |
2397 | { | |
2398 | return cpufreq_driver->boost_enabled; | |
2399 | } | |
2400 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2401 | ||
1da177e4 LT |
2402 | /********************************************************************* |
2403 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2404 | *********************************************************************/ | |
2405 | ||
2406 | /** | |
2407 | * cpufreq_register_driver - register a CPU Frequency driver | |
2408 | * @driver_data: A struct cpufreq_driver containing the values# | |
2409 | * submitted by the CPU Frequency driver. | |
2410 | * | |
bb176f7d | 2411 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 2412 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 2413 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2414 | * |
2415 | */ | |
221dee28 | 2416 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2417 | { |
2418 | unsigned long flags; | |
2419 | int ret; | |
2420 | ||
a7b422cd KRW |
2421 | if (cpufreq_disabled()) |
2422 | return -ENODEV; | |
2423 | ||
1da177e4 | 2424 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2425 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2426 | driver_data->target) || |
2427 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2428 | driver_data->target)) || |
2429 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2430 | return -EINVAL; |
2431 | ||
2d06d8c4 | 2432 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2433 | |
0d1857a1 | 2434 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2435 | if (cpufreq_driver) { |
0d1857a1 | 2436 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4dea5806 | 2437 | return -EEXIST; |
1da177e4 | 2438 | } |
1c3d85dd | 2439 | cpufreq_driver = driver_data; |
0d1857a1 | 2440 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2441 | |
bc68b7df VK |
2442 | if (driver_data->setpolicy) |
2443 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2444 | ||
6f19efc0 LM |
2445 | if (cpufreq_boost_supported()) { |
2446 | /* | |
2447 | * Check if driver provides function to enable boost - | |
2448 | * if not, use cpufreq_boost_set_sw as default | |
2449 | */ | |
2450 | if (!cpufreq_driver->set_boost) | |
2451 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; | |
2452 | ||
2453 | ret = cpufreq_sysfs_create_file(&boost.attr); | |
2454 | if (ret) { | |
2455 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
e837f9b5 | 2456 | __func__); |
6f19efc0 LM |
2457 | goto err_null_driver; |
2458 | } | |
2459 | } | |
2460 | ||
8a25a2fd | 2461 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2462 | if (ret) |
6f19efc0 | 2463 | goto err_boost_unreg; |
1da177e4 | 2464 | |
1c3d85dd | 2465 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) { |
1da177e4 LT |
2466 | int i; |
2467 | ret = -ENODEV; | |
2468 | ||
2469 | /* check for at least one working CPU */ | |
7a6aedfa MT |
2470 | for (i = 0; i < nr_cpu_ids; i++) |
2471 | if (cpu_possible(i) && per_cpu(cpufreq_cpu_data, i)) { | |
1da177e4 | 2472 | ret = 0; |
7a6aedfa MT |
2473 | break; |
2474 | } | |
1da177e4 LT |
2475 | |
2476 | /* if all ->init() calls failed, unregister */ | |
2477 | if (ret) { | |
2d06d8c4 | 2478 | pr_debug("no CPU initialized for driver %s\n", |
e837f9b5 | 2479 | driver_data->name); |
8a25a2fd | 2480 | goto err_if_unreg; |
1da177e4 LT |
2481 | } |
2482 | } | |
2483 | ||
8f5bc2ab | 2484 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2485 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2486 | |
8f5bc2ab | 2487 | return 0; |
8a25a2fd KS |
2488 | err_if_unreg: |
2489 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 LM |
2490 | err_boost_unreg: |
2491 | if (cpufreq_boost_supported()) | |
2492 | cpufreq_sysfs_remove_file(&boost.attr); | |
8f5bc2ab | 2493 | err_null_driver: |
0d1857a1 | 2494 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2495 | cpufreq_driver = NULL; |
0d1857a1 | 2496 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4d34a67d | 2497 | return ret; |
1da177e4 LT |
2498 | } |
2499 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2500 | ||
1da177e4 LT |
2501 | /** |
2502 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2503 | * | |
bb176f7d | 2504 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2505 | * the right to do so, i.e. if you have succeeded in initialising before! |
2506 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2507 | * currently not initialised. | |
2508 | */ | |
221dee28 | 2509 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2510 | { |
2511 | unsigned long flags; | |
2512 | ||
1c3d85dd | 2513 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2514 | return -EINVAL; |
1da177e4 | 2515 | |
2d06d8c4 | 2516 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2517 | |
8a25a2fd | 2518 | subsys_interface_unregister(&cpufreq_interface); |
6f19efc0 LM |
2519 | if (cpufreq_boost_supported()) |
2520 | cpufreq_sysfs_remove_file(&boost.attr); | |
2521 | ||
65edc68c | 2522 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2523 | |
6eed9404 | 2524 | down_write(&cpufreq_rwsem); |
0d1857a1 | 2525 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2526 | |
1c3d85dd | 2527 | cpufreq_driver = NULL; |
6eed9404 | 2528 | |
0d1857a1 | 2529 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
6eed9404 | 2530 | up_write(&cpufreq_rwsem); |
1da177e4 LT |
2531 | |
2532 | return 0; | |
2533 | } | |
2534 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2535 | |
90de2a4a DA |
2536 | /* |
2537 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2538 | * or mutexes when secondary CPUs are halted. | |
2539 | */ | |
2540 | static struct syscore_ops cpufreq_syscore_ops = { | |
2541 | .shutdown = cpufreq_suspend, | |
2542 | }; | |
2543 | ||
5a01f2e8 VP |
2544 | static int __init cpufreq_core_init(void) |
2545 | { | |
a7b422cd KRW |
2546 | if (cpufreq_disabled()) |
2547 | return -ENODEV; | |
2548 | ||
2361be23 | 2549 | cpufreq_global_kobject = kobject_create(); |
8aa84ad8 TR |
2550 | BUG_ON(!cpufreq_global_kobject); |
2551 | ||
90de2a4a DA |
2552 | register_syscore_ops(&cpufreq_syscore_ops); |
2553 | ||
5a01f2e8 VP |
2554 | return 0; |
2555 | } | |
5a01f2e8 | 2556 | core_initcall(cpufreq_core_init); |