Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
2f0aea93 | 29 | #include <linux/suspend.h> |
90de2a4a | 30 | #include <linux/syscore_ops.h> |
5ff0a268 | 31 | #include <linux/tick.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
b4f0676f | 34 | static LIST_HEAD(cpufreq_policy_list); |
f963735a VK |
35 | |
36 | static inline bool policy_is_inactive(struct cpufreq_policy *policy) | |
37 | { | |
38 | return cpumask_empty(policy->cpus); | |
39 | } | |
40 | ||
f963735a | 41 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
42 | #define for_each_suitable_policy(__policy, __active) \ |
43 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
44 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
45 | |
46 | #define for_each_active_policy(__policy) \ | |
47 | for_each_suitable_policy(__policy, true) | |
48 | #define for_each_inactive_policy(__policy) \ | |
49 | for_each_suitable_policy(__policy, false) | |
50 | ||
51 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
52 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
53 | ||
f7b27061 VK |
54 | /* Iterate over governors */ |
55 | static LIST_HEAD(cpufreq_governor_list); | |
56 | #define for_each_governor(__governor) \ | |
57 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
58 | ||
1da177e4 | 59 | /** |
cd878479 | 60 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
61 | * level driver of CPUFreq support, and its spinlock. This lock |
62 | * also protects the cpufreq_cpu_data array. | |
63 | */ | |
1c3d85dd | 64 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 65 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 66 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 67 | |
2f0aea93 VK |
68 | /* Flag to suspend/resume CPUFreq governors */ |
69 | static bool cpufreq_suspended; | |
1da177e4 | 70 | |
9c0ebcf7 VK |
71 | static inline bool has_target(void) |
72 | { | |
73 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
74 | } | |
75 | ||
1da177e4 | 76 | /* internal prototypes */ |
d92d50a4 | 77 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
a92604b4 RW |
78 | static int cpufreq_init_governor(struct cpufreq_policy *policy); |
79 | static void cpufreq_exit_governor(struct cpufreq_policy *policy); | |
0a300767 | 80 | static int cpufreq_start_governor(struct cpufreq_policy *policy); |
a92604b4 RW |
81 | static void cpufreq_stop_governor(struct cpufreq_policy *policy); |
82 | static void cpufreq_governor_limits(struct cpufreq_policy *policy); | |
45482c70 | 83 | |
1da177e4 | 84 | /** |
32ee8c3e DJ |
85 | * Two notifier lists: the "policy" list is involved in the |
86 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
87 | * "transition" list for kernel code that needs to handle |
88 | * changes to devices when the CPU clock speed changes. | |
89 | * The mutex locks both lists. | |
90 | */ | |
e041c683 | 91 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 92 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 93 | |
74212ca4 | 94 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
95 | static int __init init_cpufreq_transition_notifier_list(void) |
96 | { | |
97 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 98 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
99 | return 0; |
100 | } | |
b3438f82 | 101 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 102 | |
a7b422cd | 103 | static int off __read_mostly; |
da584455 | 104 | static int cpufreq_disabled(void) |
a7b422cd KRW |
105 | { |
106 | return off; | |
107 | } | |
108 | void disable_cpufreq(void) | |
109 | { | |
110 | off = 1; | |
111 | } | |
29464f28 | 112 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 113 | |
4d5dcc42 VK |
114 | bool have_governor_per_policy(void) |
115 | { | |
0b981e70 | 116 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 117 | } |
3f869d6d | 118 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 119 | |
944e9a03 VK |
120 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
121 | { | |
122 | if (have_governor_per_policy()) | |
123 | return &policy->kobj; | |
124 | else | |
125 | return cpufreq_global_kobject; | |
126 | } | |
127 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
128 | ||
72a4ce34 VK |
129 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
130 | { | |
131 | u64 idle_time; | |
132 | u64 cur_wall_time; | |
133 | u64 busy_time; | |
134 | ||
135 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
136 | ||
137 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
138 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
139 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
140 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
141 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
142 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
143 | ||
144 | idle_time = cur_wall_time - busy_time; | |
145 | if (wall) | |
146 | *wall = cputime_to_usecs(cur_wall_time); | |
147 | ||
148 | return cputime_to_usecs(idle_time); | |
149 | } | |
150 | ||
151 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
152 | { | |
153 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
154 | ||
155 | if (idle_time == -1ULL) | |
156 | return get_cpu_idle_time_jiffy(cpu, wall); | |
157 | else if (!io_busy) | |
158 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
159 | ||
160 | return idle_time; | |
161 | } | |
162 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
163 | ||
70e9e778 VK |
164 | /* |
165 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
166 | * drivers of SMP systems. It will do following: | |
167 | * - validate & show freq table passed | |
168 | * - set policies transition latency | |
169 | * - policy->cpus with all possible CPUs | |
170 | */ | |
171 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
172 | struct cpufreq_frequency_table *table, | |
173 | unsigned int transition_latency) | |
174 | { | |
175 | int ret; | |
176 | ||
177 | ret = cpufreq_table_validate_and_show(policy, table); | |
178 | if (ret) { | |
179 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
180 | return ret; | |
181 | } | |
182 | ||
183 | policy->cpuinfo.transition_latency = transition_latency; | |
184 | ||
185 | /* | |
58405af6 | 186 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
187 | * share the clock and voltage and clock. |
188 | */ | |
189 | cpumask_setall(policy->cpus); | |
190 | ||
191 | return 0; | |
192 | } | |
193 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
194 | ||
1f0bd44e | 195 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
196 | { |
197 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
198 | ||
988bed09 VK |
199 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
200 | } | |
1f0bd44e | 201 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
202 | |
203 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
204 | { | |
205 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
206 | ||
652ed95d | 207 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
208 | pr_err("%s: No %s associated to cpu: %d\n", |
209 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
210 | return 0; |
211 | } | |
212 | ||
213 | return clk_get_rate(policy->clk) / 1000; | |
214 | } | |
215 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
216 | ||
50e9c852 VK |
217 | /** |
218 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
219 | * | |
220 | * @cpu: cpu to find policy for. | |
221 | * | |
222 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
223 | * It also increments the kobject reference count to mark it busy and so would | |
224 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
225 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
226 | * freed as that depends on the kobj count. | |
227 | * | |
50e9c852 VK |
228 | * Return: A valid policy on success, otherwise NULL on failure. |
229 | */ | |
6eed9404 | 230 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 231 | { |
6eed9404 | 232 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
233 | unsigned long flags; |
234 | ||
1b947c90 | 235 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
236 | return NULL; |
237 | ||
1da177e4 | 238 | /* get the cpufreq driver */ |
1c3d85dd | 239 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 240 | |
6eed9404 VK |
241 | if (cpufreq_driver) { |
242 | /* get the CPU */ | |
988bed09 | 243 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
244 | if (policy) |
245 | kobject_get(&policy->kobj); | |
246 | } | |
1da177e4 | 247 | |
6eed9404 | 248 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 249 | |
3a3e9e06 | 250 | return policy; |
a9144436 | 251 | } |
1da177e4 LT |
252 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
253 | ||
50e9c852 VK |
254 | /** |
255 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
256 | * | |
257 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
258 | * | |
259 | * This decrements the kobject reference count incremented earlier by calling | |
260 | * cpufreq_cpu_get(). | |
50e9c852 | 261 | */ |
3a3e9e06 | 262 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 263 | { |
6eed9404 | 264 | kobject_put(&policy->kobj); |
1da177e4 LT |
265 | } |
266 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
267 | ||
1da177e4 LT |
268 | /********************************************************************* |
269 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
270 | *********************************************************************/ | |
271 | ||
272 | /** | |
273 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
274 | * | |
275 | * This function alters the system "loops_per_jiffy" for the clock | |
276 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 277 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
278 | * per-CPU loops_per_jiffy value wherever possible. |
279 | */ | |
858119e1 | 280 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 281 | { |
39c132ee VK |
282 | #ifndef CONFIG_SMP |
283 | static unsigned long l_p_j_ref; | |
284 | static unsigned int l_p_j_ref_freq; | |
285 | ||
1da177e4 LT |
286 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
287 | return; | |
288 | ||
289 | if (!l_p_j_ref_freq) { | |
290 | l_p_j_ref = loops_per_jiffy; | |
291 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
292 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
293 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 294 | } |
0b443ead | 295 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
296 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
297 | ci->new); | |
e837f9b5 JP |
298 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
299 | loops_per_jiffy, ci->new); | |
1da177e4 | 300 | } |
1da177e4 | 301 | #endif |
39c132ee | 302 | } |
1da177e4 | 303 | |
0956df9c | 304 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 305 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
306 | { |
307 | BUG_ON(irqs_disabled()); | |
308 | ||
d5aaffa9 DB |
309 | if (cpufreq_disabled()) |
310 | return; | |
311 | ||
1c3d85dd | 312 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 313 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 314 | state, freqs->new); |
1da177e4 | 315 | |
1da177e4 | 316 | switch (state) { |
e4472cb3 | 317 | |
1da177e4 | 318 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 319 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
320 | * which is not equal to what the cpufreq core thinks is |
321 | * "old frequency". | |
1da177e4 | 322 | */ |
1c3d85dd | 323 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
324 | if ((policy) && (policy->cpu == freqs->cpu) && |
325 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
326 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
327 | freqs->old, policy->cur); | |
e4472cb3 | 328 | freqs->old = policy->cur; |
1da177e4 LT |
329 | } |
330 | } | |
b4dfdbb3 | 331 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 332 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
333 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
334 | break; | |
e4472cb3 | 335 | |
1da177e4 LT |
336 | case CPUFREQ_POSTCHANGE: |
337 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
338 | pr_debug("FREQ: %lu - CPU: %lu\n", |
339 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 340 | trace_cpu_frequency(freqs->new, freqs->cpu); |
1aefc75b | 341 | cpufreq_stats_record_transition(policy, freqs->new); |
b4dfdbb3 | 342 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 343 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
344 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
345 | policy->cur = freqs->new; | |
1da177e4 LT |
346 | break; |
347 | } | |
1da177e4 | 348 | } |
bb176f7d | 349 | |
b43a7ffb VK |
350 | /** |
351 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
352 | * on frequency transition. | |
353 | * | |
354 | * This function calls the transition notifiers and the "adjust_jiffies" | |
355 | * function. It is called twice on all CPU frequency changes that have | |
356 | * external effects. | |
357 | */ | |
236a9800 | 358 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
359 | struct cpufreq_freqs *freqs, unsigned int state) |
360 | { | |
361 | for_each_cpu(freqs->cpu, policy->cpus) | |
362 | __cpufreq_notify_transition(policy, freqs, state); | |
363 | } | |
1da177e4 | 364 | |
f7ba3b41 | 365 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 366 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
367 | struct cpufreq_freqs *freqs, int transition_failed) |
368 | { | |
369 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
370 | if (!transition_failed) | |
371 | return; | |
372 | ||
373 | swap(freqs->old, freqs->new); | |
374 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
375 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
376 | } | |
f7ba3b41 | 377 | |
12478cf0 SB |
378 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
379 | struct cpufreq_freqs *freqs) | |
380 | { | |
ca654dc3 SB |
381 | |
382 | /* | |
383 | * Catch double invocations of _begin() which lead to self-deadlock. | |
384 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
385 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
386 | * double invocations are very low. Moreover, there are scenarios | |
387 | * where these checks can emit false-positive warnings in these | |
388 | * drivers; so we avoid that by skipping them altogether. | |
389 | */ | |
390 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
391 | && current == policy->transition_task); | |
392 | ||
12478cf0 SB |
393 | wait: |
394 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
395 | ||
396 | spin_lock(&policy->transition_lock); | |
397 | ||
398 | if (unlikely(policy->transition_ongoing)) { | |
399 | spin_unlock(&policy->transition_lock); | |
400 | goto wait; | |
401 | } | |
402 | ||
403 | policy->transition_ongoing = true; | |
ca654dc3 | 404 | policy->transition_task = current; |
12478cf0 SB |
405 | |
406 | spin_unlock(&policy->transition_lock); | |
407 | ||
408 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
409 | } | |
410 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
411 | ||
412 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
413 | struct cpufreq_freqs *freqs, int transition_failed) | |
414 | { | |
415 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
416 | return; | |
417 | ||
418 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
419 | ||
420 | policy->transition_ongoing = false; | |
ca654dc3 | 421 | policy->transition_task = NULL; |
12478cf0 SB |
422 | |
423 | wake_up(&policy->transition_wait); | |
424 | } | |
425 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
426 | ||
b7898fda RW |
427 | /* |
428 | * Fast frequency switching status count. Positive means "enabled", negative | |
429 | * means "disabled" and 0 means "not decided yet". | |
430 | */ | |
431 | static int cpufreq_fast_switch_count; | |
432 | static DEFINE_MUTEX(cpufreq_fast_switch_lock); | |
433 | ||
434 | static void cpufreq_list_transition_notifiers(void) | |
435 | { | |
436 | struct notifier_block *nb; | |
437 | ||
438 | pr_info("Registered transition notifiers:\n"); | |
439 | ||
440 | mutex_lock(&cpufreq_transition_notifier_list.mutex); | |
441 | ||
442 | for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) | |
443 | pr_info("%pF\n", nb->notifier_call); | |
444 | ||
445 | mutex_unlock(&cpufreq_transition_notifier_list.mutex); | |
446 | } | |
447 | ||
448 | /** | |
449 | * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. | |
450 | * @policy: cpufreq policy to enable fast frequency switching for. | |
451 | * | |
452 | * Try to enable fast frequency switching for @policy. | |
453 | * | |
454 | * The attempt will fail if there is at least one transition notifier registered | |
455 | * at this point, as fast frequency switching is quite fundamentally at odds | |
456 | * with transition notifiers. Thus if successful, it will make registration of | |
457 | * transition notifiers fail going forward. | |
458 | */ | |
459 | void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) | |
460 | { | |
461 | lockdep_assert_held(&policy->rwsem); | |
462 | ||
463 | if (!policy->fast_switch_possible) | |
464 | return; | |
465 | ||
466 | mutex_lock(&cpufreq_fast_switch_lock); | |
467 | if (cpufreq_fast_switch_count >= 0) { | |
468 | cpufreq_fast_switch_count++; | |
469 | policy->fast_switch_enabled = true; | |
470 | } else { | |
471 | pr_warn("CPU%u: Fast frequency switching not enabled\n", | |
472 | policy->cpu); | |
473 | cpufreq_list_transition_notifiers(); | |
474 | } | |
475 | mutex_unlock(&cpufreq_fast_switch_lock); | |
476 | } | |
477 | EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); | |
478 | ||
6c9d9c81 RW |
479 | /** |
480 | * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. | |
481 | * @policy: cpufreq policy to disable fast frequency switching for. | |
482 | */ | |
483 | void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) | |
b7898fda RW |
484 | { |
485 | mutex_lock(&cpufreq_fast_switch_lock); | |
486 | if (policy->fast_switch_enabled) { | |
487 | policy->fast_switch_enabled = false; | |
488 | if (!WARN_ON(cpufreq_fast_switch_count <= 0)) | |
489 | cpufreq_fast_switch_count--; | |
490 | } | |
491 | mutex_unlock(&cpufreq_fast_switch_lock); | |
492 | } | |
6c9d9c81 | 493 | EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); |
1da177e4 | 494 | |
e3c06236 SM |
495 | /** |
496 | * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported | |
497 | * one. | |
498 | * @target_freq: target frequency to resolve. | |
499 | * | |
500 | * The target to driver frequency mapping is cached in the policy. | |
501 | * | |
502 | * Return: Lowest driver-supported frequency greater than or equal to the | |
503 | * given target_freq, subject to policy (min/max) and driver limitations. | |
504 | */ | |
505 | unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, | |
506 | unsigned int target_freq) | |
507 | { | |
508 | target_freq = clamp_val(target_freq, policy->min, policy->max); | |
509 | policy->cached_target_freq = target_freq; | |
abe8bd02 VK |
510 | |
511 | if (cpufreq_driver->target_index) { | |
512 | int idx; | |
513 | ||
514 | idx = cpufreq_frequency_table_target(policy, target_freq, | |
515 | CPUFREQ_RELATION_L); | |
516 | policy->cached_resolved_idx = idx; | |
517 | return policy->freq_table[idx].frequency; | |
518 | } | |
519 | ||
e3c06236 SM |
520 | if (cpufreq_driver->resolve_freq) |
521 | return cpufreq_driver->resolve_freq(policy, target_freq); | |
abe8bd02 VK |
522 | |
523 | return target_freq; | |
e3c06236 | 524 | } |
ae2c1ca6 | 525 | EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); |
e3c06236 | 526 | |
1da177e4 LT |
527 | /********************************************************************* |
528 | * SYSFS INTERFACE * | |
529 | *********************************************************************/ | |
8a5c74a1 | 530 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
531 | struct attribute *attr, char *buf) |
532 | { | |
533 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
534 | } | |
535 | ||
536 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
537 | const char *buf, size_t count) | |
538 | { | |
539 | int ret, enable; | |
540 | ||
541 | ret = sscanf(buf, "%d", &enable); | |
542 | if (ret != 1 || enable < 0 || enable > 1) | |
543 | return -EINVAL; | |
544 | ||
545 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
546 | pr_err("%s: Cannot %s BOOST!\n", |
547 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
548 | return -EINVAL; |
549 | } | |
550 | ||
e837f9b5 JP |
551 | pr_debug("%s: cpufreq BOOST %s\n", |
552 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
553 | |
554 | return count; | |
555 | } | |
556 | define_one_global_rw(boost); | |
1da177e4 | 557 | |
42f91fa1 | 558 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
559 | { |
560 | struct cpufreq_governor *t; | |
561 | ||
f7b27061 | 562 | for_each_governor(t) |
7c4f4539 | 563 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
564 | return t; |
565 | ||
566 | return NULL; | |
567 | } | |
568 | ||
1da177e4 LT |
569 | /** |
570 | * cpufreq_parse_governor - parse a governor string | |
571 | */ | |
905d77cd | 572 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
573 | struct cpufreq_governor **governor) |
574 | { | |
3bcb09a3 | 575 | int err = -EINVAL; |
1c3d85dd | 576 | |
1c3d85dd | 577 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 578 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 579 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 580 | err = 0; |
7c4f4539 | 581 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 582 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 583 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 584 | err = 0; |
1da177e4 | 585 | } |
2e1cc3a5 | 586 | } else { |
1da177e4 | 587 | struct cpufreq_governor *t; |
3bcb09a3 | 588 | |
3fc54d37 | 589 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 590 | |
42f91fa1 | 591 | t = find_governor(str_governor); |
3bcb09a3 | 592 | |
ea714970 | 593 | if (t == NULL) { |
1a8e1463 | 594 | int ret; |
ea714970 | 595 | |
1a8e1463 KC |
596 | mutex_unlock(&cpufreq_governor_mutex); |
597 | ret = request_module("cpufreq_%s", str_governor); | |
598 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 599 | |
1a8e1463 | 600 | if (ret == 0) |
42f91fa1 | 601 | t = find_governor(str_governor); |
ea714970 JF |
602 | } |
603 | ||
3bcb09a3 JF |
604 | if (t != NULL) { |
605 | *governor = t; | |
606 | err = 0; | |
1da177e4 | 607 | } |
3bcb09a3 | 608 | |
3fc54d37 | 609 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 610 | } |
3bcb09a3 | 611 | return err; |
1da177e4 | 612 | } |
1da177e4 | 613 | |
1da177e4 | 614 | /** |
e08f5f5b GS |
615 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
616 | * print out cpufreq information | |
1da177e4 LT |
617 | * |
618 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
619 | * "unsigned int". | |
620 | */ | |
621 | ||
32ee8c3e DJ |
622 | #define show_one(file_name, object) \ |
623 | static ssize_t show_##file_name \ | |
905d77cd | 624 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 625 | { \ |
29464f28 | 626 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
627 | } |
628 | ||
629 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
630 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 631 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
632 | show_one(scaling_min_freq, min); |
633 | show_one(scaling_max_freq, max); | |
c034b02e | 634 | |
09347b29 | 635 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
636 | { |
637 | ssize_t ret; | |
638 | ||
639 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
640 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
641 | else | |
642 | ret = sprintf(buf, "%u\n", policy->cur); | |
643 | return ret; | |
644 | } | |
1da177e4 | 645 | |
037ce839 | 646 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 647 | struct cpufreq_policy *new_policy); |
7970e08b | 648 | |
1da177e4 LT |
649 | /** |
650 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
651 | */ | |
652 | #define store_one(file_name, object) \ | |
653 | static ssize_t store_##file_name \ | |
905d77cd | 654 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 655 | { \ |
619c144c | 656 | int ret, temp; \ |
1da177e4 LT |
657 | struct cpufreq_policy new_policy; \ |
658 | \ | |
8fa5b631 | 659 | memcpy(&new_policy, policy, sizeof(*policy)); \ |
1da177e4 | 660 | \ |
29464f28 | 661 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
662 | if (ret != 1) \ |
663 | return -EINVAL; \ | |
664 | \ | |
619c144c | 665 | temp = new_policy.object; \ |
037ce839 | 666 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
667 | if (!ret) \ |
668 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
669 | \ |
670 | return ret ? ret : count; \ | |
671 | } | |
672 | ||
29464f28 DJ |
673 | store_one(scaling_min_freq, min); |
674 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
675 | |
676 | /** | |
677 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
678 | */ | |
905d77cd DJ |
679 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
680 | char *buf) | |
1da177e4 | 681 | { |
d92d50a4 | 682 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
683 | if (!cur_freq) |
684 | return sprintf(buf, "<unknown>"); | |
685 | return sprintf(buf, "%u\n", cur_freq); | |
686 | } | |
687 | ||
1da177e4 LT |
688 | /** |
689 | * show_scaling_governor - show the current policy for the specified CPU | |
690 | */ | |
905d77cd | 691 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 692 | { |
29464f28 | 693 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
694 | return sprintf(buf, "powersave\n"); |
695 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
696 | return sprintf(buf, "performance\n"); | |
697 | else if (policy->governor) | |
4b972f0b | 698 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 699 | policy->governor->name); |
1da177e4 LT |
700 | return -EINVAL; |
701 | } | |
702 | ||
1da177e4 LT |
703 | /** |
704 | * store_scaling_governor - store policy for the specified CPU | |
705 | */ | |
905d77cd DJ |
706 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
707 | const char *buf, size_t count) | |
1da177e4 | 708 | { |
5136fa56 | 709 | int ret; |
1da177e4 LT |
710 | char str_governor[16]; |
711 | struct cpufreq_policy new_policy; | |
712 | ||
8fa5b631 | 713 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 714 | |
29464f28 | 715 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
716 | if (ret != 1) |
717 | return -EINVAL; | |
718 | ||
e08f5f5b GS |
719 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
720 | &new_policy.governor)) | |
1da177e4 LT |
721 | return -EINVAL; |
722 | ||
037ce839 | 723 | ret = cpufreq_set_policy(policy, &new_policy); |
88dc4384 | 724 | return ret ? ret : count; |
1da177e4 LT |
725 | } |
726 | ||
727 | /** | |
728 | * show_scaling_driver - show the cpufreq driver currently loaded | |
729 | */ | |
905d77cd | 730 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 731 | { |
1c3d85dd | 732 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
733 | } |
734 | ||
735 | /** | |
736 | * show_scaling_available_governors - show the available CPUfreq governors | |
737 | */ | |
905d77cd DJ |
738 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
739 | char *buf) | |
1da177e4 LT |
740 | { |
741 | ssize_t i = 0; | |
742 | struct cpufreq_governor *t; | |
743 | ||
9c0ebcf7 | 744 | if (!has_target()) { |
1da177e4 LT |
745 | i += sprintf(buf, "performance powersave"); |
746 | goto out; | |
747 | } | |
748 | ||
f7b27061 | 749 | for_each_governor(t) { |
29464f28 DJ |
750 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
751 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 752 | goto out; |
4b972f0b | 753 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 754 | } |
7d5e350f | 755 | out: |
1da177e4 LT |
756 | i += sprintf(&buf[i], "\n"); |
757 | return i; | |
758 | } | |
e8628dd0 | 759 | |
f4fd3797 | 760 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
761 | { |
762 | ssize_t i = 0; | |
763 | unsigned int cpu; | |
764 | ||
835481d9 | 765 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
766 | if (i) |
767 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
768 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
769 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 770 | break; |
1da177e4 LT |
771 | } |
772 | i += sprintf(&buf[i], "\n"); | |
773 | return i; | |
774 | } | |
f4fd3797 | 775 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 776 | |
e8628dd0 DW |
777 | /** |
778 | * show_related_cpus - show the CPUs affected by each transition even if | |
779 | * hw coordination is in use | |
780 | */ | |
781 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
782 | { | |
f4fd3797 | 783 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
784 | } |
785 | ||
786 | /** | |
787 | * show_affected_cpus - show the CPUs affected by each transition | |
788 | */ | |
789 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
790 | { | |
f4fd3797 | 791 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
792 | } |
793 | ||
9e76988e | 794 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 795 | const char *buf, size_t count) |
9e76988e VP |
796 | { |
797 | unsigned int freq = 0; | |
798 | unsigned int ret; | |
799 | ||
879000f9 | 800 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
801 | return -EINVAL; |
802 | ||
803 | ret = sscanf(buf, "%u", &freq); | |
804 | if (ret != 1) | |
805 | return -EINVAL; | |
806 | ||
807 | policy->governor->store_setspeed(policy, freq); | |
808 | ||
809 | return count; | |
810 | } | |
811 | ||
812 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
813 | { | |
879000f9 | 814 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
815 | return sprintf(buf, "<unsupported>\n"); |
816 | ||
817 | return policy->governor->show_setspeed(policy, buf); | |
818 | } | |
1da177e4 | 819 | |
e2f74f35 | 820 | /** |
8bf1ac72 | 821 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
822 | */ |
823 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
824 | { | |
825 | unsigned int limit; | |
826 | int ret; | |
1c3d85dd RW |
827 | if (cpufreq_driver->bios_limit) { |
828 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
829 | if (!ret) |
830 | return sprintf(buf, "%u\n", limit); | |
831 | } | |
832 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
833 | } | |
834 | ||
6dad2a29 BP |
835 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
836 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
837 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
838 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
839 | cpufreq_freq_attr_ro(scaling_available_governors); | |
840 | cpufreq_freq_attr_ro(scaling_driver); | |
841 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
842 | cpufreq_freq_attr_ro(bios_limit); | |
843 | cpufreq_freq_attr_ro(related_cpus); | |
844 | cpufreq_freq_attr_ro(affected_cpus); | |
845 | cpufreq_freq_attr_rw(scaling_min_freq); | |
846 | cpufreq_freq_attr_rw(scaling_max_freq); | |
847 | cpufreq_freq_attr_rw(scaling_governor); | |
848 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 849 | |
905d77cd | 850 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
851 | &cpuinfo_min_freq.attr, |
852 | &cpuinfo_max_freq.attr, | |
ed129784 | 853 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
854 | &scaling_min_freq.attr, |
855 | &scaling_max_freq.attr, | |
856 | &affected_cpus.attr, | |
e8628dd0 | 857 | &related_cpus.attr, |
1da177e4 LT |
858 | &scaling_governor.attr, |
859 | &scaling_driver.attr, | |
860 | &scaling_available_governors.attr, | |
9e76988e | 861 | &scaling_setspeed.attr, |
1da177e4 LT |
862 | NULL |
863 | }; | |
864 | ||
29464f28 DJ |
865 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
866 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 867 | |
29464f28 | 868 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 869 | { |
905d77cd DJ |
870 | struct cpufreq_policy *policy = to_policy(kobj); |
871 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 872 | ssize_t ret; |
6eed9404 | 873 | |
ad7722da | 874 | down_read(&policy->rwsem); |
6541aef0 | 875 | ret = fattr->show(policy, buf); |
ad7722da | 876 | up_read(&policy->rwsem); |
1b750e3b | 877 | |
1da177e4 LT |
878 | return ret; |
879 | } | |
880 | ||
905d77cd DJ |
881 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
882 | const char *buf, size_t count) | |
1da177e4 | 883 | { |
905d77cd DJ |
884 | struct cpufreq_policy *policy = to_policy(kobj); |
885 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 886 | ssize_t ret = -EINVAL; |
6eed9404 | 887 | |
4f750c93 SB |
888 | get_online_cpus(); |
889 | ||
6541aef0 RW |
890 | if (cpu_online(policy->cpu)) { |
891 | down_write(&policy->rwsem); | |
e08f5f5b | 892 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
893 | up_write(&policy->rwsem); |
894 | } | |
e08f5f5b | 895 | |
4f750c93 SB |
896 | put_online_cpus(); |
897 | ||
1da177e4 LT |
898 | return ret; |
899 | } | |
900 | ||
905d77cd | 901 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 902 | { |
905d77cd | 903 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 904 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
905 | complete(&policy->kobj_unregister); |
906 | } | |
907 | ||
52cf25d0 | 908 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
909 | .show = show, |
910 | .store = store, | |
911 | }; | |
912 | ||
913 | static struct kobj_type ktype_cpufreq = { | |
914 | .sysfs_ops = &sysfs_ops, | |
915 | .default_attrs = default_attrs, | |
916 | .release = cpufreq_sysfs_release, | |
917 | }; | |
918 | ||
87549141 VK |
919 | static int add_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) |
920 | { | |
921 | struct device *cpu_dev; | |
922 | ||
923 | pr_debug("%s: Adding symlink for CPU: %u\n", __func__, cpu); | |
924 | ||
925 | if (!policy) | |
926 | return 0; | |
927 | ||
928 | cpu_dev = get_cpu_device(cpu); | |
929 | if (WARN_ON(!cpu_dev)) | |
930 | return 0; | |
931 | ||
932 | return sysfs_create_link(&cpu_dev->kobj, &policy->kobj, "cpufreq"); | |
933 | } | |
934 | ||
935 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) | |
936 | { | |
937 | struct device *cpu_dev; | |
938 | ||
939 | pr_debug("%s: Removing symlink for CPU: %u\n", __func__, cpu); | |
940 | ||
941 | cpu_dev = get_cpu_device(cpu); | |
942 | if (WARN_ON(!cpu_dev)) | |
943 | return; | |
944 | ||
945 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); | |
946 | } | |
947 | ||
948 | /* Add/remove symlinks for all related CPUs */ | |
308b60e7 | 949 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
950 | { |
951 | unsigned int j; | |
952 | int ret = 0; | |
953 | ||
87549141 | 954 | /* Some related CPUs might not be present (physically hotplugged) */ |
559ed407 | 955 | for_each_cpu(j, policy->real_cpus) { |
87549141 | 956 | ret = add_cpu_dev_symlink(policy, j); |
71c3461e RW |
957 | if (ret) |
958 | break; | |
19d6f7ec | 959 | } |
87549141 | 960 | |
19d6f7ec DJ |
961 | return ret; |
962 | } | |
963 | ||
87549141 VK |
964 | static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy) |
965 | { | |
966 | unsigned int j; | |
967 | ||
968 | /* Some related CPUs might not be present (physically hotplugged) */ | |
96bdda61 | 969 | for_each_cpu(j, policy->real_cpus) |
87549141 | 970 | remove_cpu_dev_symlink(policy, j); |
87549141 VK |
971 | } |
972 | ||
d9612a49 | 973 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
974 | { |
975 | struct freq_attr **drv_attr; | |
909a694e | 976 | int ret = 0; |
909a694e | 977 | |
909a694e | 978 | /* set up files for this cpu device */ |
1c3d85dd | 979 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 980 | while (drv_attr && *drv_attr) { |
909a694e DJ |
981 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
982 | if (ret) | |
6d4e81ed | 983 | return ret; |
909a694e DJ |
984 | drv_attr++; |
985 | } | |
1c3d85dd | 986 | if (cpufreq_driver->get) { |
909a694e DJ |
987 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
988 | if (ret) | |
6d4e81ed | 989 | return ret; |
909a694e | 990 | } |
c034b02e DB |
991 | |
992 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
993 | if (ret) | |
6d4e81ed | 994 | return ret; |
c034b02e | 995 | |
1c3d85dd | 996 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
997 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
998 | if (ret) | |
6d4e81ed | 999 | return ret; |
e2f74f35 | 1000 | } |
909a694e | 1001 | |
6d4e81ed | 1002 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
1003 | } |
1004 | ||
de1df26b RW |
1005 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
1006 | { | |
1007 | return NULL; | |
1008 | } | |
1009 | ||
7f0fa40f | 1010 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1011 | { |
6e2c89d1 | 1012 | struct cpufreq_governor *gov = NULL; |
e18f1682 | 1013 | struct cpufreq_policy new_policy; |
e18f1682 | 1014 | |
d5b73cd8 | 1015 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 1016 | |
6e2c89d1 | 1017 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 1018 | gov = find_governor(policy->last_governor); |
de1df26b | 1019 | if (gov) { |
6e2c89d1 | 1020 | pr_debug("Restoring governor %s for cpu %d\n", |
1021 | policy->governor->name, policy->cpu); | |
de1df26b RW |
1022 | } else { |
1023 | gov = cpufreq_default_governor(); | |
1024 | if (!gov) | |
1025 | return -ENODATA; | |
1026 | } | |
6e2c89d1 | 1027 | |
1028 | new_policy.governor = gov; | |
1029 | ||
69030dd1 SP |
1030 | /* Use the default policy if there is no last_policy. */ |
1031 | if (cpufreq_driver->setpolicy) { | |
1032 | if (policy->last_policy) | |
1033 | new_policy.policy = policy->last_policy; | |
1034 | else | |
1035 | cpufreq_parse_governor(gov->name, &new_policy.policy, | |
1036 | NULL); | |
1037 | } | |
ecf7e461 | 1038 | /* set default policy */ |
7f0fa40f | 1039 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
1040 | } |
1041 | ||
d9612a49 | 1042 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1043 | { |
9c0ebcf7 | 1044 | int ret = 0; |
fcf80582 | 1045 | |
bb29ae15 VK |
1046 | /* Has this CPU been taken care of already? */ |
1047 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1048 | return 0; | |
1049 | ||
49f18560 | 1050 | down_write(&policy->rwsem); |
45482c70 RW |
1051 | if (has_target()) |
1052 | cpufreq_stop_governor(policy); | |
fcf80582 | 1053 | |
fcf80582 | 1054 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1055 | |
9c0ebcf7 | 1056 | if (has_target()) { |
0a300767 | 1057 | ret = cpufreq_start_governor(policy); |
49f18560 | 1058 | if (ret) |
3de9bdeb | 1059 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1060 | } |
49f18560 VK |
1061 | up_write(&policy->rwsem); |
1062 | return ret; | |
fcf80582 | 1063 | } |
1da177e4 | 1064 | |
11eb69b9 VK |
1065 | static void handle_update(struct work_struct *work) |
1066 | { | |
1067 | struct cpufreq_policy *policy = | |
1068 | container_of(work, struct cpufreq_policy, update); | |
1069 | unsigned int cpu = policy->cpu; | |
1070 | pr_debug("handle_update for cpu %u called\n", cpu); | |
1071 | cpufreq_update_policy(cpu); | |
fcf80582 | 1072 | } |
1da177e4 | 1073 | |
a34e63b1 | 1074 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 | 1075 | { |
a34e63b1 | 1076 | struct device *dev = get_cpu_device(cpu); |
e9698cc5 | 1077 | struct cpufreq_policy *policy; |
edd4a893 | 1078 | int ret; |
e9698cc5 | 1079 | |
a34e63b1 RW |
1080 | if (WARN_ON(!dev)) |
1081 | return NULL; | |
1082 | ||
e9698cc5 SB |
1083 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
1084 | if (!policy) | |
1085 | return NULL; | |
1086 | ||
1087 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1088 | goto err_free_policy; | |
1089 | ||
1090 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1091 | goto err_free_cpumask; | |
1092 | ||
559ed407 RW |
1093 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1094 | goto err_free_rcpumask; | |
1095 | ||
edd4a893 VK |
1096 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1097 | cpufreq_global_kobject, "policy%u", cpu); | |
1098 | if (ret) { | |
1099 | pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); | |
1100 | goto err_free_real_cpus; | |
1101 | } | |
1102 | ||
c88a1f8b | 1103 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1104 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1105 | spin_lock_init(&policy->transition_lock); |
1106 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1107 | init_completion(&policy->kobj_unregister); |
1108 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1109 | |
a34e63b1 | 1110 | policy->cpu = cpu; |
e9698cc5 SB |
1111 | return policy; |
1112 | ||
edd4a893 VK |
1113 | err_free_real_cpus: |
1114 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1115 | err_free_rcpumask: |
1116 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1117 | err_free_cpumask: |
1118 | free_cpumask_var(policy->cpus); | |
1119 | err_free_policy: | |
1120 | kfree(policy); | |
1121 | ||
1122 | return NULL; | |
1123 | } | |
1124 | ||
2fc3384d | 1125 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify) |
42f921a6 VK |
1126 | { |
1127 | struct kobject *kobj; | |
1128 | struct completion *cmp; | |
1129 | ||
2fc3384d VK |
1130 | if (notify) |
1131 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1132 | CPUFREQ_REMOVE_POLICY, policy); | |
fcd7af91 | 1133 | |
87549141 | 1134 | down_write(&policy->rwsem); |
1aefc75b | 1135 | cpufreq_stats_free_table(policy); |
87549141 | 1136 | cpufreq_remove_dev_symlink(policy); |
42f921a6 VK |
1137 | kobj = &policy->kobj; |
1138 | cmp = &policy->kobj_unregister; | |
87549141 | 1139 | up_write(&policy->rwsem); |
42f921a6 VK |
1140 | kobject_put(kobj); |
1141 | ||
1142 | /* | |
1143 | * We need to make sure that the underlying kobj is | |
1144 | * actually not referenced anymore by anybody before we | |
1145 | * proceed with unloading. | |
1146 | */ | |
1147 | pr_debug("waiting for dropping of refcount\n"); | |
1148 | wait_for_completion(cmp); | |
1149 | pr_debug("wait complete\n"); | |
1150 | } | |
1151 | ||
3654c5cc | 1152 | static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify) |
e9698cc5 | 1153 | { |
988bed09 VK |
1154 | unsigned long flags; |
1155 | int cpu; | |
1156 | ||
1157 | /* Remove policy from list */ | |
1158 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1159 | list_del(&policy->policy_list); | |
1160 | ||
1161 | for_each_cpu(cpu, policy->related_cpus) | |
1162 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1163 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1164 | ||
3654c5cc | 1165 | cpufreq_policy_put_kobj(policy, notify); |
559ed407 | 1166 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1167 | free_cpumask_var(policy->related_cpus); |
1168 | free_cpumask_var(policy->cpus); | |
1169 | kfree(policy); | |
1170 | } | |
1171 | ||
0b275352 | 1172 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1173 | { |
7f0c020a | 1174 | struct cpufreq_policy *policy; |
194d99c7 | 1175 | bool new_policy; |
1da177e4 | 1176 | unsigned long flags; |
0b275352 RW |
1177 | unsigned int j; |
1178 | int ret; | |
87549141 | 1179 | |
0b275352 | 1180 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1181 | |
bb29ae15 | 1182 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1183 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1184 | if (policy) { |
9104bb26 | 1185 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1186 | if (!policy_is_inactive(policy)) |
d9612a49 | 1187 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1188 | |
11ce707e | 1189 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1190 | new_policy = false; |
11ce707e RW |
1191 | down_write(&policy->rwsem); |
1192 | policy->cpu = cpu; | |
1193 | policy->governor = NULL; | |
1194 | up_write(&policy->rwsem); | |
1195 | } else { | |
194d99c7 | 1196 | new_policy = true; |
a34e63b1 | 1197 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1198 | if (!policy) |
d4d854d6 | 1199 | return -ENOMEM; |
72368d12 | 1200 | } |
0d66b91e | 1201 | |
835481d9 | 1202 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1203 | |
1da177e4 LT |
1204 | /* call driver. From then on the cpufreq must be able |
1205 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1206 | */ | |
1c3d85dd | 1207 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1208 | if (ret) { |
2d06d8c4 | 1209 | pr_debug("initialization failed\n"); |
8101f997 | 1210 | goto out_free_policy; |
1da177e4 | 1211 | } |
643ae6e8 | 1212 | |
6d4e81ed TV |
1213 | down_write(&policy->rwsem); |
1214 | ||
194d99c7 | 1215 | if (new_policy) { |
4d1f3a5b | 1216 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1217 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1218 | /* Remember CPUs present at the policy creation time. */ |
559ed407 | 1219 | cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask); |
4d1f3a5b | 1220 | } |
559ed407 | 1221 | |
5a7e56a5 VK |
1222 | /* |
1223 | * affected cpus must always be the one, which are online. We aren't | |
1224 | * managing offline cpus here. | |
1225 | */ | |
1226 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1227 | ||
194d99c7 | 1228 | if (new_policy) { |
5a7e56a5 VK |
1229 | policy->user_policy.min = policy->min; |
1230 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1231 | |
988bed09 VK |
1232 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1233 | for_each_cpu(j, policy->related_cpus) | |
1234 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1235 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1236 | } | |
652ed95d | 1237 | |
2ed99e39 | 1238 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1239 | policy->cur = cpufreq_driver->get(policy->cpu); |
1240 | if (!policy->cur) { | |
1241 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1242 | goto out_exit_policy; |
da60ce9f VK |
1243 | } |
1244 | } | |
1245 | ||
d3916691 VK |
1246 | /* |
1247 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1248 | * frequency table present with cpufreq core. In such cases CPU might be | |
1249 | * unstable if it has to run on that frequency for long duration of time | |
1250 | * and so its better to set it to a frequency which is specified in | |
1251 | * freq-table. This also makes cpufreq stats inconsistent as | |
1252 | * cpufreq-stats would fail to register because current frequency of CPU | |
1253 | * isn't found in freq-table. | |
1254 | * | |
1255 | * Because we don't want this change to effect boot process badly, we go | |
1256 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1257 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1258 | * is initialized to zero). | |
1259 | * | |
1260 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1261 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1262 | * equal to target-freq. | |
1263 | */ | |
1264 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1265 | && has_target()) { | |
1266 | /* Are we running at unknown frequency ? */ | |
1267 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1268 | if (ret == -EINVAL) { | |
1269 | /* Warn user and fix it */ | |
1270 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1271 | __func__, policy->cpu, policy->cur); | |
1272 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1273 | CPUFREQ_RELATION_L); | |
1274 | ||
1275 | /* | |
1276 | * Reaching here after boot in a few seconds may not | |
1277 | * mean that system will remain stable at "unknown" | |
1278 | * frequency for longer duration. Hence, a BUG_ON(). | |
1279 | */ | |
1280 | BUG_ON(ret); | |
1281 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1282 | __func__, policy->cpu, policy->cur); | |
1283 | } | |
1284 | } | |
1285 | ||
194d99c7 | 1286 | if (new_policy) { |
d9612a49 | 1287 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1288 | if (ret) |
8101f997 | 1289 | goto out_exit_policy; |
1aefc75b RW |
1290 | |
1291 | cpufreq_stats_create_table(policy); | |
fcd7af91 VK |
1292 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1293 | CPUFREQ_CREATE_POLICY, policy); | |
8ff69732 | 1294 | |
988bed09 VK |
1295 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1296 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1297 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1298 | } | |
9515f4d6 | 1299 | |
388612ba VK |
1300 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1301 | CPUFREQ_START, policy); | |
1302 | ||
7f0fa40f VK |
1303 | ret = cpufreq_init_policy(policy); |
1304 | if (ret) { | |
1305 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1306 | __func__, cpu, ret); | |
194d99c7 RW |
1307 | /* cpufreq_policy_free() will notify based on this */ |
1308 | new_policy = false; | |
1309 | goto out_exit_policy; | |
08fd8c1c | 1310 | } |
e18f1682 | 1311 | |
4e97b631 | 1312 | up_write(&policy->rwsem); |
08fd8c1c | 1313 | |
038c5b3e | 1314 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1315 | |
7c45cf31 VK |
1316 | /* Callback for handling stuff after policy is ready */ |
1317 | if (cpufreq_driver->ready) | |
1318 | cpufreq_driver->ready(policy); | |
1319 | ||
2d06d8c4 | 1320 | pr_debug("initialization complete\n"); |
87c32271 | 1321 | |
1da177e4 LT |
1322 | return 0; |
1323 | ||
8101f997 | 1324 | out_exit_policy: |
7106e02b PB |
1325 | up_write(&policy->rwsem); |
1326 | ||
da60ce9f VK |
1327 | if (cpufreq_driver->exit) |
1328 | cpufreq_driver->exit(policy); | |
8101f997 | 1329 | out_free_policy: |
194d99c7 | 1330 | cpufreq_policy_free(policy, !new_policy); |
1da177e4 LT |
1331 | return ret; |
1332 | } | |
1333 | ||
0b275352 RW |
1334 | /** |
1335 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1336 | * @dev: CPU device. | |
1337 | * @sif: Subsystem interface structure pointer (not used) | |
1338 | */ | |
1339 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1340 | { | |
a794d613 | 1341 | struct cpufreq_policy *policy; |
0b275352 | 1342 | unsigned cpu = dev->id; |
0b275352 RW |
1343 | |
1344 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1345 | ||
a794d613 RW |
1346 | if (cpu_online(cpu)) |
1347 | return cpufreq_online(cpu); | |
0b275352 | 1348 | |
a794d613 RW |
1349 | /* |
1350 | * A hotplug notifier will follow and we will handle it as CPU online | |
1351 | * then. For now, just create the sysfs link, unless there is no policy | |
1352 | * or the link is already present. | |
1353 | */ | |
1354 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1355 | if (!policy || cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
1356 | return 0; | |
6eed9404 | 1357 | |
a794d613 | 1358 | return add_cpu_dev_symlink(policy, cpu); |
1da177e4 LT |
1359 | } |
1360 | ||
69cee714 | 1361 | static void cpufreq_offline(unsigned int cpu) |
1da177e4 | 1362 | { |
3a3e9e06 | 1363 | struct cpufreq_policy *policy; |
69cee714 | 1364 | int ret; |
1da177e4 | 1365 | |
b8eed8af | 1366 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1367 | |
988bed09 | 1368 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1369 | if (!policy) { |
b8eed8af | 1370 | pr_debug("%s: No cpu_data found\n", __func__); |
15c0b4d2 | 1371 | return; |
1da177e4 | 1372 | } |
1da177e4 | 1373 | |
49f18560 | 1374 | down_write(&policy->rwsem); |
45482c70 RW |
1375 | if (has_target()) |
1376 | cpufreq_stop_governor(policy); | |
1da177e4 | 1377 | |
9591becb | 1378 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1379 | |
9591becb VK |
1380 | if (policy_is_inactive(policy)) { |
1381 | if (has_target()) | |
1382 | strncpy(policy->last_governor, policy->governor->name, | |
1383 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1384 | else |
1385 | policy->last_policy = policy->policy; | |
9591becb VK |
1386 | } else if (cpu == policy->cpu) { |
1387 | /* Nominate new CPU */ | |
1388 | policy->cpu = cpumask_any(policy->cpus); | |
1389 | } | |
084f3493 | 1390 | |
9591becb VK |
1391 | /* Start governor again for active policy */ |
1392 | if (!policy_is_inactive(policy)) { | |
1393 | if (has_target()) { | |
0a300767 | 1394 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1395 | if (ret) |
1396 | pr_err("%s: Failed to start governor\n", __func__); | |
1397 | } | |
cedb70af | 1398 | |
49f18560 | 1399 | goto unlock; |
cedb70af SB |
1400 | } |
1401 | ||
69cee714 VK |
1402 | if (cpufreq_driver->stop_cpu) |
1403 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1404 | |
36be3418 RW |
1405 | if (has_target()) |
1406 | cpufreq_exit_governor(policy); | |
1da177e4 | 1407 | |
87549141 VK |
1408 | /* |
1409 | * Perform the ->exit() even during light-weight tear-down, | |
1410 | * since this is a core component, and is essential for the | |
1411 | * subsequent light-weight ->init() to succeed. | |
1412 | */ | |
55582bcc | 1413 | if (cpufreq_driver->exit) { |
87549141 | 1414 | cpufreq_driver->exit(policy); |
55582bcc SP |
1415 | policy->freq_table = NULL; |
1416 | } | |
49f18560 VK |
1417 | |
1418 | unlock: | |
1419 | up_write(&policy->rwsem); | |
1da177e4 LT |
1420 | } |
1421 | ||
cedb70af | 1422 | /** |
27a862e9 | 1423 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1424 | * |
1425 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1426 | */ |
71db87ba | 1427 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1428 | { |
8a25a2fd | 1429 | unsigned int cpu = dev->id; |
559ed407 | 1430 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1431 | |
559ed407 | 1432 | if (!policy) |
1af115d6 | 1433 | return; |
87549141 | 1434 | |
69cee714 VK |
1435 | if (cpu_online(cpu)) |
1436 | cpufreq_offline(cpu); | |
87549141 | 1437 | |
559ed407 | 1438 | cpumask_clear_cpu(cpu, policy->real_cpus); |
f344dae0 | 1439 | remove_cpu_dev_symlink(policy, cpu); |
87549141 | 1440 | |
f344dae0 | 1441 | if (cpumask_empty(policy->real_cpus)) |
3654c5cc | 1442 | cpufreq_policy_free(policy, true); |
5a01f2e8 VP |
1443 | } |
1444 | ||
1da177e4 | 1445 | /** |
bb176f7d VK |
1446 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1447 | * in deep trouble. | |
a1e1dc41 | 1448 | * @policy: policy managing CPUs |
1da177e4 LT |
1449 | * @new_freq: CPU frequency the CPU actually runs at |
1450 | * | |
29464f28 DJ |
1451 | * We adjust to current frequency first, and need to clean up later. |
1452 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1453 | */ |
a1e1dc41 | 1454 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1455 | unsigned int new_freq) |
1da177e4 LT |
1456 | { |
1457 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1458 | |
e837f9b5 | 1459 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1460 | policy->cur, new_freq); |
1da177e4 | 1461 | |
a1e1dc41 | 1462 | freqs.old = policy->cur; |
1da177e4 | 1463 | freqs.new = new_freq; |
b43a7ffb | 1464 | |
8fec051e VK |
1465 | cpufreq_freq_transition_begin(policy, &freqs); |
1466 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1467 | } |
1468 | ||
32ee8c3e | 1469 | /** |
4ab70df4 | 1470 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1471 | * @cpu: CPU number |
1472 | * | |
1473 | * This is the last known freq, without actually getting it from the driver. | |
1474 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1475 | */ | |
1476 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1477 | { | |
9e21ba8b | 1478 | struct cpufreq_policy *policy; |
e08f5f5b | 1479 | unsigned int ret_freq = 0; |
c75361c0 | 1480 | unsigned long flags; |
95235ca2 | 1481 | |
c75361c0 RC |
1482 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1483 | ||
1484 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1485 | ret_freq = cpufreq_driver->get(cpu); | |
1486 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1487 | return ret_freq; | |
1488 | } | |
1489 | ||
1490 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1491 | |
1492 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1493 | if (policy) { |
e08f5f5b | 1494 | ret_freq = policy->cur; |
95235ca2 VP |
1495 | cpufreq_cpu_put(policy); |
1496 | } | |
1497 | ||
4d34a67d | 1498 | return ret_freq; |
95235ca2 VP |
1499 | } |
1500 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1501 | ||
3d737108 JB |
1502 | /** |
1503 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1504 | * @cpu: CPU number | |
1505 | * | |
1506 | * Just return the max possible frequency for a given CPU. | |
1507 | */ | |
1508 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1509 | { | |
1510 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1511 | unsigned int ret_freq = 0; | |
1512 | ||
1513 | if (policy) { | |
1514 | ret_freq = policy->max; | |
1515 | cpufreq_cpu_put(policy); | |
1516 | } | |
1517 | ||
1518 | return ret_freq; | |
1519 | } | |
1520 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1521 | ||
d92d50a4 | 1522 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1523 | { |
e08f5f5b | 1524 | unsigned int ret_freq = 0; |
5800043b | 1525 | |
1c3d85dd | 1526 | if (!cpufreq_driver->get) |
4d34a67d | 1527 | return ret_freq; |
1da177e4 | 1528 | |
d92d50a4 | 1529 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1530 | |
b7898fda RW |
1531 | /* |
1532 | * Updating inactive policies is invalid, so avoid doing that. Also | |
1533 | * if fast frequency switching is used with the given policy, the check | |
1534 | * against policy->cur is pointless, so skip it in that case too. | |
1535 | */ | |
1536 | if (unlikely(policy_is_inactive(policy)) || policy->fast_switch_enabled) | |
11e584cf VK |
1537 | return ret_freq; |
1538 | ||
e08f5f5b | 1539 | if (ret_freq && policy->cur && |
1c3d85dd | 1540 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1541 | /* verify no discrepancy between actual and |
1542 | saved value exists */ | |
1543 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1544 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1545 | schedule_work(&policy->update); |
1546 | } | |
1547 | } | |
1548 | ||
4d34a67d | 1549 | return ret_freq; |
5a01f2e8 | 1550 | } |
1da177e4 | 1551 | |
5a01f2e8 VP |
1552 | /** |
1553 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1554 | * @cpu: CPU number | |
1555 | * | |
1556 | * Get the CPU current (static) CPU frequency | |
1557 | */ | |
1558 | unsigned int cpufreq_get(unsigned int cpu) | |
1559 | { | |
999976e0 | 1560 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1561 | unsigned int ret_freq = 0; |
5a01f2e8 | 1562 | |
999976e0 AP |
1563 | if (policy) { |
1564 | down_read(&policy->rwsem); | |
d92d50a4 | 1565 | ret_freq = __cpufreq_get(policy); |
999976e0 | 1566 | up_read(&policy->rwsem); |
5a01f2e8 | 1567 | |
999976e0 AP |
1568 | cpufreq_cpu_put(policy); |
1569 | } | |
6eed9404 | 1570 | |
4d34a67d | 1571 | return ret_freq; |
1da177e4 LT |
1572 | } |
1573 | EXPORT_SYMBOL(cpufreq_get); | |
1574 | ||
999f5729 RW |
1575 | static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy) |
1576 | { | |
1577 | unsigned int new_freq; | |
1578 | ||
1579 | new_freq = cpufreq_driver->get(policy->cpu); | |
1580 | if (!new_freq) | |
1581 | return 0; | |
1582 | ||
1583 | if (!policy->cur) { | |
1584 | pr_debug("cpufreq: Driver did not initialize current freq\n"); | |
1585 | policy->cur = new_freq; | |
1586 | } else if (policy->cur != new_freq && has_target()) { | |
1587 | cpufreq_out_of_sync(policy, new_freq); | |
1588 | } | |
1589 | ||
1590 | return new_freq; | |
1591 | } | |
1592 | ||
8a25a2fd KS |
1593 | static struct subsys_interface cpufreq_interface = { |
1594 | .name = "cpufreq", | |
1595 | .subsys = &cpu_subsys, | |
1596 | .add_dev = cpufreq_add_dev, | |
1597 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1598 | }; |
1599 | ||
e28867ea VK |
1600 | /* |
1601 | * In case platform wants some specific frequency to be configured | |
1602 | * during suspend.. | |
1603 | */ | |
1604 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1605 | { | |
1606 | int ret; | |
1607 | ||
1608 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1609 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1610 | return 0; | |
e28867ea VK |
1611 | } |
1612 | ||
1613 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1614 | policy->suspend_freq); | |
1615 | ||
1616 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1617 | CPUFREQ_RELATION_H); | |
1618 | if (ret) | |
1619 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1620 | __func__, policy->suspend_freq, ret); | |
1621 | ||
1622 | return ret; | |
1623 | } | |
1624 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1625 | ||
42d4dc3f | 1626 | /** |
2f0aea93 | 1627 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1628 | * |
2f0aea93 VK |
1629 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1630 | * as some platforms can't change frequency after this point in suspend cycle. | |
1631 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1632 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1633 | */ |
2f0aea93 | 1634 | void cpufreq_suspend(void) |
42d4dc3f | 1635 | { |
3a3e9e06 | 1636 | struct cpufreq_policy *policy; |
42d4dc3f | 1637 | |
2f0aea93 VK |
1638 | if (!cpufreq_driver) |
1639 | return; | |
42d4dc3f | 1640 | |
ba41e1bc | 1641 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1642 | goto suspend; |
42d4dc3f | 1643 | |
2f0aea93 VK |
1644 | pr_debug("%s: Suspending Governors\n", __func__); |
1645 | ||
f963735a | 1646 | for_each_active_policy(policy) { |
ba41e1bc RW |
1647 | if (has_target()) { |
1648 | down_write(&policy->rwsem); | |
45482c70 | 1649 | cpufreq_stop_governor(policy); |
ba41e1bc | 1650 | up_write(&policy->rwsem); |
ba41e1bc RW |
1651 | } |
1652 | ||
1653 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
2f0aea93 VK |
1654 | pr_err("%s: Failed to suspend driver: %p\n", __func__, |
1655 | policy); | |
42d4dc3f | 1656 | } |
b1b12bab VK |
1657 | |
1658 | suspend: | |
1659 | cpufreq_suspended = true; | |
42d4dc3f BH |
1660 | } |
1661 | ||
1da177e4 | 1662 | /** |
2f0aea93 | 1663 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1664 | * |
2f0aea93 VK |
1665 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1666 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1667 | */ |
2f0aea93 | 1668 | void cpufreq_resume(void) |
1da177e4 | 1669 | { |
3a3e9e06 | 1670 | struct cpufreq_policy *policy; |
49f18560 | 1671 | int ret; |
1da177e4 | 1672 | |
2f0aea93 VK |
1673 | if (!cpufreq_driver) |
1674 | return; | |
1da177e4 | 1675 | |
8e30444e LT |
1676 | cpufreq_suspended = false; |
1677 | ||
ba41e1bc | 1678 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1679 | return; |
1da177e4 | 1680 | |
2f0aea93 | 1681 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1682 | |
f963735a | 1683 | for_each_active_policy(policy) { |
49f18560 | 1684 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1685 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1686 | policy); | |
ba41e1bc | 1687 | } else if (has_target()) { |
49f18560 | 1688 | down_write(&policy->rwsem); |
0a300767 | 1689 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1690 | up_write(&policy->rwsem); |
1691 | ||
1692 | if (ret) | |
1693 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1694 | __func__, policy); | |
1695 | } | |
2f0aea93 VK |
1696 | } |
1697 | } | |
1da177e4 | 1698 | |
9d95046e BP |
1699 | /** |
1700 | * cpufreq_get_current_driver - return current driver's name | |
1701 | * | |
1702 | * Return the name string of the currently loaded cpufreq driver | |
1703 | * or NULL, if none. | |
1704 | */ | |
1705 | const char *cpufreq_get_current_driver(void) | |
1706 | { | |
1c3d85dd RW |
1707 | if (cpufreq_driver) |
1708 | return cpufreq_driver->name; | |
1709 | ||
1710 | return NULL; | |
9d95046e BP |
1711 | } |
1712 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1713 | |
51315cdf TP |
1714 | /** |
1715 | * cpufreq_get_driver_data - return current driver data | |
1716 | * | |
1717 | * Return the private data of the currently loaded cpufreq | |
1718 | * driver, or NULL if no cpufreq driver is loaded. | |
1719 | */ | |
1720 | void *cpufreq_get_driver_data(void) | |
1721 | { | |
1722 | if (cpufreq_driver) | |
1723 | return cpufreq_driver->driver_data; | |
1724 | ||
1725 | return NULL; | |
1726 | } | |
1727 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1728 | ||
1da177e4 LT |
1729 | /********************************************************************* |
1730 | * NOTIFIER LISTS INTERFACE * | |
1731 | *********************************************************************/ | |
1732 | ||
1733 | /** | |
1734 | * cpufreq_register_notifier - register a driver with cpufreq | |
1735 | * @nb: notifier function to register | |
1736 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1737 | * | |
32ee8c3e | 1738 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1739 | * are notified about clock rate changes (once before and once after |
1740 | * the transition), or a list of drivers that are notified about | |
1741 | * changes in cpufreq policy. | |
1742 | * | |
1743 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1744 | * blocking_notifier_chain_register. |
1da177e4 LT |
1745 | */ |
1746 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1747 | { | |
1748 | int ret; | |
1749 | ||
d5aaffa9 DB |
1750 | if (cpufreq_disabled()) |
1751 | return -EINVAL; | |
1752 | ||
74212ca4 CEB |
1753 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1754 | ||
1da177e4 LT |
1755 | switch (list) { |
1756 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1757 | mutex_lock(&cpufreq_fast_switch_lock); |
1758 | ||
1759 | if (cpufreq_fast_switch_count > 0) { | |
1760 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1761 | return -EBUSY; | |
1762 | } | |
b4dfdbb3 | 1763 | ret = srcu_notifier_chain_register( |
e041c683 | 1764 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1765 | if (!ret) |
1766 | cpufreq_fast_switch_count--; | |
1767 | ||
1768 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1769 | break; |
1770 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1771 | ret = blocking_notifier_chain_register( |
1772 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1773 | break; |
1774 | default: | |
1775 | ret = -EINVAL; | |
1776 | } | |
1da177e4 LT |
1777 | |
1778 | return ret; | |
1779 | } | |
1780 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1781 | ||
1da177e4 LT |
1782 | /** |
1783 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1784 | * @nb: notifier block to be unregistered | |
bb176f7d | 1785 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1786 | * |
1787 | * Remove a driver from the CPU frequency notifier list. | |
1788 | * | |
1789 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1790 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1791 | */ |
1792 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1793 | { | |
1794 | int ret; | |
1795 | ||
d5aaffa9 DB |
1796 | if (cpufreq_disabled()) |
1797 | return -EINVAL; | |
1798 | ||
1da177e4 LT |
1799 | switch (list) { |
1800 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1801 | mutex_lock(&cpufreq_fast_switch_lock); |
1802 | ||
b4dfdbb3 | 1803 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1804 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1805 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
1806 | cpufreq_fast_switch_count++; | |
1807 | ||
1808 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1809 | break; |
1810 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1811 | ret = blocking_notifier_chain_unregister( |
1812 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1813 | break; |
1814 | default: | |
1815 | ret = -EINVAL; | |
1816 | } | |
1da177e4 LT |
1817 | |
1818 | return ret; | |
1819 | } | |
1820 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1821 | ||
1822 | ||
1823 | /********************************************************************* | |
1824 | * GOVERNORS * | |
1825 | *********************************************************************/ | |
1826 | ||
b7898fda RW |
1827 | /** |
1828 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
1829 | * @policy: cpufreq policy to switch the frequency for. | |
1830 | * @target_freq: New frequency to set (may be approximate). | |
1831 | * | |
1832 | * Carry out a fast frequency switch without sleeping. | |
1833 | * | |
1834 | * The driver's ->fast_switch() callback invoked by this function must be | |
1835 | * suitable for being called from within RCU-sched read-side critical sections | |
1836 | * and it is expected to select the minimum available frequency greater than or | |
1837 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
1838 | * | |
1839 | * This function must not be called if policy->fast_switch_enabled is unset. | |
1840 | * | |
1841 | * Governors calling this function must guarantee that it will never be invoked | |
1842 | * twice in parallel for the same policy and that it will never be called in | |
1843 | * parallel with either ->target() or ->target_index() for the same policy. | |
1844 | * | |
1845 | * If CPUFREQ_ENTRY_INVALID is returned by the driver's ->fast_switch() | |
1846 | * callback to indicate an error condition, the hardware configuration must be | |
1847 | * preserved. | |
1848 | */ | |
1849 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
1850 | unsigned int target_freq) | |
1851 | { | |
b9af6948 | 1852 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
b7898fda RW |
1853 | |
1854 | return cpufreq_driver->fast_switch(policy, target_freq); | |
1855 | } | |
1856 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
1857 | ||
1c03a2d0 VK |
1858 | /* Must set freqs->new to intermediate frequency */ |
1859 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1860 | struct cpufreq_freqs *freqs, int index) | |
1861 | { | |
1862 | int ret; | |
1863 | ||
1864 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1865 | ||
1866 | /* We don't need to switch to intermediate freq */ | |
1867 | if (!freqs->new) | |
1868 | return 0; | |
1869 | ||
1870 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1871 | __func__, policy->cpu, freqs->old, freqs->new); | |
1872 | ||
1873 | cpufreq_freq_transition_begin(policy, freqs); | |
1874 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1875 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1876 | ||
1877 | if (ret) | |
1878 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1879 | __func__, ret); | |
1880 | ||
1881 | return ret; | |
1882 | } | |
1883 | ||
23727845 | 1884 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 1885 | { |
1c03a2d0 VK |
1886 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1887 | unsigned int intermediate_freq = 0; | |
23727845 | 1888 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
1889 | int retval = -EINVAL; |
1890 | bool notify; | |
1891 | ||
23727845 VK |
1892 | if (newfreq == policy->cur) |
1893 | return 0; | |
1894 | ||
8d65775d | 1895 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 1896 | if (notify) { |
1c03a2d0 VK |
1897 | /* Handle switching to intermediate frequency */ |
1898 | if (cpufreq_driver->get_intermediate) { | |
1899 | retval = __target_intermediate(policy, &freqs, index); | |
1900 | if (retval) | |
1901 | return retval; | |
1902 | ||
1903 | intermediate_freq = freqs.new; | |
1904 | /* Set old freq to intermediate */ | |
1905 | if (intermediate_freq) | |
1906 | freqs.old = freqs.new; | |
1907 | } | |
8d65775d | 1908 | |
23727845 | 1909 | freqs.new = newfreq; |
8d65775d VK |
1910 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1911 | __func__, policy->cpu, freqs.old, freqs.new); | |
1912 | ||
1913 | cpufreq_freq_transition_begin(policy, &freqs); | |
1914 | } | |
1915 | ||
1916 | retval = cpufreq_driver->target_index(policy, index); | |
1917 | if (retval) | |
1918 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1919 | retval); | |
1920 | ||
1c03a2d0 | 1921 | if (notify) { |
8d65775d VK |
1922 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1923 | ||
1c03a2d0 VK |
1924 | /* |
1925 | * Failed after setting to intermediate freq? Driver should have | |
1926 | * reverted back to initial frequency and so should we. Check | |
1927 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1928 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1929 | */ |
1930 | if (unlikely(retval && intermediate_freq)) { | |
1931 | freqs.old = intermediate_freq; | |
1932 | freqs.new = policy->restore_freq; | |
1933 | cpufreq_freq_transition_begin(policy, &freqs); | |
1934 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1935 | } | |
1936 | } | |
1937 | ||
8d65775d VK |
1938 | return retval; |
1939 | } | |
1940 | ||
1da177e4 LT |
1941 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1942 | unsigned int target_freq, | |
1943 | unsigned int relation) | |
1944 | { | |
7249924e | 1945 | unsigned int old_target_freq = target_freq; |
d218ed77 | 1946 | int index; |
c32b6b8e | 1947 | |
a7b422cd KRW |
1948 | if (cpufreq_disabled()) |
1949 | return -ENODEV; | |
1950 | ||
7249924e | 1951 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 1952 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
1953 | |
1954 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1955 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1956 | |
9c0ebcf7 VK |
1957 | /* |
1958 | * This might look like a redundant call as we are checking it again | |
1959 | * after finding index. But it is left intentionally for cases where | |
1960 | * exactly same freq is called again and so we can save on few function | |
1961 | * calls. | |
1962 | */ | |
5a1c0228 VK |
1963 | if (target_freq == policy->cur) |
1964 | return 0; | |
1965 | ||
1c03a2d0 VK |
1966 | /* Save last value to restore later on errors */ |
1967 | policy->restore_freq = policy->cur; | |
1968 | ||
1c3d85dd | 1969 | if (cpufreq_driver->target) |
6019d23a | 1970 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 1971 | |
6019d23a RW |
1972 | if (!cpufreq_driver->target_index) |
1973 | return -EINVAL; | |
9c0ebcf7 | 1974 | |
d218ed77 | 1975 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 1976 | |
23727845 | 1977 | return __target_index(policy, index); |
1da177e4 LT |
1978 | } |
1979 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1980 | ||
1da177e4 LT |
1981 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1982 | unsigned int target_freq, | |
1983 | unsigned int relation) | |
1984 | { | |
f1829e4a | 1985 | int ret = -EINVAL; |
1da177e4 | 1986 | |
ad7722da | 1987 | down_write(&policy->rwsem); |
1da177e4 LT |
1988 | |
1989 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1990 | ||
ad7722da | 1991 | up_write(&policy->rwsem); |
1da177e4 | 1992 | |
1da177e4 LT |
1993 | return ret; |
1994 | } | |
1995 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1996 | ||
de1df26b RW |
1997 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
1998 | { | |
1999 | return NULL; | |
2000 | } | |
2001 | ||
a92604b4 | 2002 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 2003 | { |
cc993cab | 2004 | int ret; |
6afde10c | 2005 | |
2f0aea93 VK |
2006 | /* Don't start any governor operations if we are entering suspend */ |
2007 | if (cpufreq_suspended) | |
2008 | return 0; | |
cb57720b EZ |
2009 | /* |
2010 | * Governor might not be initiated here if ACPI _PPC changed | |
2011 | * notification happened, so check it. | |
2012 | */ | |
2013 | if (!policy->governor) | |
2014 | return -EINVAL; | |
2f0aea93 | 2015 | |
1c256245 TR |
2016 | if (policy->governor->max_transition_latency && |
2017 | policy->cpuinfo.transition_latency > | |
2018 | policy->governor->max_transition_latency) { | |
de1df26b RW |
2019 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2020 | ||
2021 | if (gov) { | |
e837f9b5 JP |
2022 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
2023 | policy->governor->name, gov->name); | |
6afde10c | 2024 | policy->governor = gov; |
de1df26b RW |
2025 | } else { |
2026 | return -EINVAL; | |
6afde10c | 2027 | } |
1c256245 | 2028 | } |
1da177e4 | 2029 | |
a92604b4 RW |
2030 | if (!try_module_get(policy->governor->owner)) |
2031 | return -EINVAL; | |
95731ebb | 2032 | |
a92604b4 | 2033 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2034 | |
e788892b RW |
2035 | if (policy->governor->init) { |
2036 | ret = policy->governor->init(policy); | |
2037 | if (ret) { | |
36be3418 | 2038 | module_put(policy->governor->owner); |
e788892b RW |
2039 | return ret; |
2040 | } | |
36be3418 | 2041 | } |
1da177e4 | 2042 | |
a92604b4 RW |
2043 | return 0; |
2044 | } | |
2045 | ||
2046 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2047 | { | |
2048 | if (cpufreq_suspended || !policy->governor) | |
2049 | return; | |
2050 | ||
2051 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2052 | ||
e788892b RW |
2053 | if (policy->governor->exit) |
2054 | policy->governor->exit(policy); | |
a92604b4 | 2055 | |
a92604b4 | 2056 | module_put(policy->governor->owner); |
1da177e4 LT |
2057 | } |
2058 | ||
0a300767 RW |
2059 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
2060 | { | |
2061 | int ret; | |
2062 | ||
a92604b4 RW |
2063 | if (cpufreq_suspended) |
2064 | return 0; | |
2065 | ||
2066 | if (!policy->governor) | |
2067 | return -EINVAL; | |
2068 | ||
2069 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2070 | ||
3bbf8fe3 RW |
2071 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) |
2072 | cpufreq_update_current_freq(policy); | |
2073 | ||
e788892b RW |
2074 | if (policy->governor->start) { |
2075 | ret = policy->governor->start(policy); | |
2076 | if (ret) | |
2077 | return ret; | |
2078 | } | |
2079 | ||
2080 | if (policy->governor->limits) | |
2081 | policy->governor->limits(policy); | |
d6ff44d6 | 2082 | |
d6ff44d6 | 2083 | return 0; |
0a300767 RW |
2084 | } |
2085 | ||
a92604b4 RW |
2086 | static void cpufreq_stop_governor(struct cpufreq_policy *policy) |
2087 | { | |
2088 | if (cpufreq_suspended || !policy->governor) | |
2089 | return; | |
2090 | ||
2091 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2092 | ||
e788892b RW |
2093 | if (policy->governor->stop) |
2094 | policy->governor->stop(policy); | |
a92604b4 RW |
2095 | } |
2096 | ||
2097 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2098 | { | |
2099 | if (cpufreq_suspended || !policy->governor) | |
2100 | return; | |
2101 | ||
2102 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2103 | ||
e788892b RW |
2104 | if (policy->governor->limits) |
2105 | policy->governor->limits(policy); | |
0a300767 RW |
2106 | } |
2107 | ||
1da177e4 LT |
2108 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2109 | { | |
3bcb09a3 | 2110 | int err; |
1da177e4 LT |
2111 | |
2112 | if (!governor) | |
2113 | return -EINVAL; | |
2114 | ||
a7b422cd KRW |
2115 | if (cpufreq_disabled()) |
2116 | return -ENODEV; | |
2117 | ||
3fc54d37 | 2118 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2119 | |
3bcb09a3 | 2120 | err = -EBUSY; |
42f91fa1 | 2121 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2122 | err = 0; |
2123 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2124 | } |
1da177e4 | 2125 | |
32ee8c3e | 2126 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2127 | return err; |
1da177e4 LT |
2128 | } |
2129 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2130 | ||
1da177e4 LT |
2131 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2132 | { | |
4573237b VK |
2133 | struct cpufreq_policy *policy; |
2134 | unsigned long flags; | |
90e41bac | 2135 | |
1da177e4 LT |
2136 | if (!governor) |
2137 | return; | |
2138 | ||
a7b422cd KRW |
2139 | if (cpufreq_disabled()) |
2140 | return; | |
2141 | ||
4573237b VK |
2142 | /* clear last_governor for all inactive policies */ |
2143 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2144 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2145 | if (!strcmp(policy->last_governor, governor->name)) { |
2146 | policy->governor = NULL; | |
4573237b | 2147 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2148 | } |
90e41bac | 2149 | } |
4573237b | 2150 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2151 | |
3fc54d37 | 2152 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2153 | list_del(&governor->governor_list); |
3fc54d37 | 2154 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2155 | return; |
2156 | } | |
2157 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2158 | ||
2159 | ||
1da177e4 LT |
2160 | /********************************************************************* |
2161 | * POLICY INTERFACE * | |
2162 | *********************************************************************/ | |
2163 | ||
2164 | /** | |
2165 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2166 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2167 | * is written | |
1da177e4 LT |
2168 | * |
2169 | * Reads the current cpufreq policy. | |
2170 | */ | |
2171 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2172 | { | |
2173 | struct cpufreq_policy *cpu_policy; | |
2174 | if (!policy) | |
2175 | return -EINVAL; | |
2176 | ||
2177 | cpu_policy = cpufreq_cpu_get(cpu); | |
2178 | if (!cpu_policy) | |
2179 | return -EINVAL; | |
2180 | ||
d5b73cd8 | 2181 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2182 | |
2183 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2184 | return 0; |
2185 | } | |
2186 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2187 | ||
153d7f3f | 2188 | /* |
037ce839 VK |
2189 | * policy : current policy. |
2190 | * new_policy: policy to be set. | |
153d7f3f | 2191 | */ |
037ce839 | 2192 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2193 | struct cpufreq_policy *new_policy) |
1da177e4 | 2194 | { |
d9a789c7 RW |
2195 | struct cpufreq_governor *old_gov; |
2196 | int ret; | |
1da177e4 | 2197 | |
e837f9b5 JP |
2198 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2199 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2200 | |
d5b73cd8 | 2201 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2202 | |
fba9573b PX |
2203 | /* |
2204 | * This check works well when we store new min/max freq attributes, | |
2205 | * because new_policy is a copy of policy with one field updated. | |
2206 | */ | |
2207 | if (new_policy->min > new_policy->max) | |
d9a789c7 | 2208 | return -EINVAL; |
9c9a43ed | 2209 | |
1da177e4 | 2210 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2211 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2212 | if (ret) |
d9a789c7 | 2213 | return ret; |
1da177e4 | 2214 | |
1da177e4 | 2215 | /* adjust if necessary - all reasons */ |
e041c683 | 2216 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2217 | CPUFREQ_ADJUST, new_policy); |
1da177e4 | 2218 | |
bb176f7d VK |
2219 | /* |
2220 | * verify the cpu speed can be set within this limit, which might be | |
2221 | * different to the first one | |
2222 | */ | |
3a3e9e06 | 2223 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2224 | if (ret) |
d9a789c7 | 2225 | return ret; |
1da177e4 LT |
2226 | |
2227 | /* notification of the new policy */ | |
e041c683 | 2228 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2229 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2230 | |
3a3e9e06 VK |
2231 | policy->min = new_policy->min; |
2232 | policy->max = new_policy->max; | |
1da177e4 | 2233 | |
e3c06236 SM |
2234 | policy->cached_target_freq = UINT_MAX; |
2235 | ||
2d06d8c4 | 2236 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2237 | policy->min, policy->max); |
1da177e4 | 2238 | |
1c3d85dd | 2239 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2240 | policy->policy = new_policy->policy; |
2d06d8c4 | 2241 | pr_debug("setting range\n"); |
d9a789c7 RW |
2242 | return cpufreq_driver->setpolicy(new_policy); |
2243 | } | |
1da177e4 | 2244 | |
0a300767 RW |
2245 | if (new_policy->governor == policy->governor) { |
2246 | pr_debug("cpufreq: governor limits update\n"); | |
a92604b4 | 2247 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2248 | return 0; |
0a300767 | 2249 | } |
7bd353a9 | 2250 | |
d9a789c7 RW |
2251 | pr_debug("governor switch\n"); |
2252 | ||
2253 | /* save old, working values */ | |
2254 | old_gov = policy->governor; | |
2255 | /* end old governor */ | |
2256 | if (old_gov) { | |
45482c70 | 2257 | cpufreq_stop_governor(policy); |
36be3418 | 2258 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2259 | } |
2260 | ||
d9a789c7 RW |
2261 | /* start new governor */ |
2262 | policy->governor = new_policy->governor; | |
a92604b4 | 2263 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2264 | if (!ret) { |
0a300767 RW |
2265 | ret = cpufreq_start_governor(policy); |
2266 | if (!ret) { | |
2267 | pr_debug("cpufreq: governor change\n"); | |
2268 | return 0; | |
2269 | } | |
b7898fda | 2270 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2271 | } |
2272 | ||
2273 | /* new governor failed, so re-start old one */ | |
2274 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2275 | if (old_gov) { | |
2276 | policy->governor = old_gov; | |
a92604b4 | 2277 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2278 | policy->governor = NULL; |
2279 | else | |
0a300767 | 2280 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2281 | } |
2282 | ||
4bc384ae | 2283 | return ret; |
1da177e4 LT |
2284 | } |
2285 | ||
1da177e4 LT |
2286 | /** |
2287 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2288 | * @cpu: CPU which shall be re-evaluated | |
2289 | * | |
25985edc | 2290 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2291 | * at different times. |
2292 | */ | |
2293 | int cpufreq_update_policy(unsigned int cpu) | |
2294 | { | |
3a3e9e06 VK |
2295 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2296 | struct cpufreq_policy new_policy; | |
f1829e4a | 2297 | int ret; |
1da177e4 | 2298 | |
fefa8ff8 AP |
2299 | if (!policy) |
2300 | return -ENODEV; | |
1da177e4 | 2301 | |
ad7722da | 2302 | down_write(&policy->rwsem); |
1da177e4 | 2303 | |
2d06d8c4 | 2304 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2305 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2306 | new_policy.min = policy->user_policy.min; |
2307 | new_policy.max = policy->user_policy.max; | |
1da177e4 | 2308 | |
bb176f7d VK |
2309 | /* |
2310 | * BIOS might change freq behind our back | |
2311 | * -> ask driver for current freq and notify governors about a change | |
2312 | */ | |
2ed99e39 | 2313 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
742c87bf RW |
2314 | if (cpufreq_suspended) { |
2315 | ret = -EAGAIN; | |
2316 | goto unlock; | |
2317 | } | |
999f5729 | 2318 | new_policy.cur = cpufreq_update_current_freq(policy); |
bd0fa9bb VK |
2319 | if (WARN_ON(!new_policy.cur)) { |
2320 | ret = -EIO; | |
fefa8ff8 | 2321 | goto unlock; |
bd0fa9bb | 2322 | } |
0961dd0d TR |
2323 | } |
2324 | ||
037ce839 | 2325 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2326 | |
fefa8ff8 | 2327 | unlock: |
ad7722da | 2328 | up_write(&policy->rwsem); |
5a01f2e8 | 2329 | |
3a3e9e06 | 2330 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2331 | return ret; |
2332 | } | |
2333 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2334 | ||
2760984f | 2335 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2336 | unsigned long action, void *hcpu) |
2337 | { | |
2338 | unsigned int cpu = (unsigned long)hcpu; | |
c32b6b8e | 2339 | |
0b275352 RW |
2340 | switch (action & ~CPU_TASKS_FROZEN) { |
2341 | case CPU_ONLINE: | |
cd73e9b0 | 2342 | case CPU_DOWN_FAILED: |
0b275352 RW |
2343 | cpufreq_online(cpu); |
2344 | break; | |
5302c3fb | 2345 | |
0b275352 | 2346 | case CPU_DOWN_PREPARE: |
69cee714 | 2347 | cpufreq_offline(cpu); |
0b275352 | 2348 | break; |
c32b6b8e AR |
2349 | } |
2350 | return NOTIFY_OK; | |
2351 | } | |
2352 | ||
9c36f746 | 2353 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2354 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2355 | }; |
1da177e4 | 2356 | |
6f19efc0 LM |
2357 | /********************************************************************* |
2358 | * BOOST * | |
2359 | *********************************************************************/ | |
2360 | static int cpufreq_boost_set_sw(int state) | |
2361 | { | |
6f19efc0 LM |
2362 | struct cpufreq_policy *policy; |
2363 | int ret = -EINVAL; | |
2364 | ||
f963735a | 2365 | for_each_active_policy(policy) { |
f8bfc116 VK |
2366 | if (!policy->freq_table) |
2367 | continue; | |
49f18560 | 2368 | |
f8bfc116 VK |
2369 | ret = cpufreq_frequency_table_cpuinfo(policy, |
2370 | policy->freq_table); | |
2371 | if (ret) { | |
2372 | pr_err("%s: Policy frequency update failed\n", | |
2373 | __func__); | |
2374 | break; | |
6f19efc0 | 2375 | } |
f8bfc116 VK |
2376 | |
2377 | down_write(&policy->rwsem); | |
2378 | policy->user_policy.max = policy->max; | |
2379 | cpufreq_governor_limits(policy); | |
2380 | up_write(&policy->rwsem); | |
6f19efc0 LM |
2381 | } |
2382 | ||
2383 | return ret; | |
2384 | } | |
2385 | ||
2386 | int cpufreq_boost_trigger_state(int state) | |
2387 | { | |
2388 | unsigned long flags; | |
2389 | int ret = 0; | |
2390 | ||
2391 | if (cpufreq_driver->boost_enabled == state) | |
2392 | return 0; | |
2393 | ||
2394 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2395 | cpufreq_driver->boost_enabled = state; | |
2396 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2397 | ||
2398 | ret = cpufreq_driver->set_boost(state); | |
2399 | if (ret) { | |
2400 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2401 | cpufreq_driver->boost_enabled = !state; | |
2402 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2403 | ||
e837f9b5 JP |
2404 | pr_err("%s: Cannot %s BOOST\n", |
2405 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2406 | } |
2407 | ||
2408 | return ret; | |
2409 | } | |
2410 | ||
41669da0 | 2411 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2412 | { |
7a6c79f2 | 2413 | return likely(cpufreq_driver) && cpufreq_driver->set_boost; |
6f19efc0 | 2414 | } |
6f19efc0 | 2415 | |
44139ed4 VK |
2416 | static int create_boost_sysfs_file(void) |
2417 | { | |
2418 | int ret; | |
2419 | ||
c82bd444 | 2420 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2421 | if (ret) |
2422 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2423 | __func__); | |
2424 | ||
2425 | return ret; | |
2426 | } | |
2427 | ||
2428 | static void remove_boost_sysfs_file(void) | |
2429 | { | |
2430 | if (cpufreq_boost_supported()) | |
c82bd444 | 2431 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2432 | } |
2433 | ||
2434 | int cpufreq_enable_boost_support(void) | |
2435 | { | |
2436 | if (!cpufreq_driver) | |
2437 | return -EINVAL; | |
2438 | ||
2439 | if (cpufreq_boost_supported()) | |
2440 | return 0; | |
2441 | ||
7a6c79f2 | 2442 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2443 | |
2444 | /* This will get removed on driver unregister */ | |
2445 | return create_boost_sysfs_file(); | |
2446 | } | |
2447 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2448 | ||
6f19efc0 LM |
2449 | int cpufreq_boost_enabled(void) |
2450 | { | |
2451 | return cpufreq_driver->boost_enabled; | |
2452 | } | |
2453 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2454 | ||
1da177e4 LT |
2455 | /********************************************************************* |
2456 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2457 | *********************************************************************/ | |
2458 | ||
2459 | /** | |
2460 | * cpufreq_register_driver - register a CPU Frequency driver | |
2461 | * @driver_data: A struct cpufreq_driver containing the values# | |
2462 | * submitted by the CPU Frequency driver. | |
2463 | * | |
bb176f7d | 2464 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2465 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2466 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2467 | * |
2468 | */ | |
221dee28 | 2469 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2470 | { |
2471 | unsigned long flags; | |
2472 | int ret; | |
2473 | ||
a7b422cd KRW |
2474 | if (cpufreq_disabled()) |
2475 | return -ENODEV; | |
2476 | ||
1da177e4 | 2477 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2478 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2479 | driver_data->target) || |
2480 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2481 | driver_data->target)) || |
2482 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2483 | return -EINVAL; |
2484 | ||
2d06d8c4 | 2485 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2486 | |
fdd320da RW |
2487 | /* Protect against concurrent CPU online/offline. */ |
2488 | get_online_cpus(); | |
2489 | ||
0d1857a1 | 2490 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2491 | if (cpufreq_driver) { |
0d1857a1 | 2492 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2493 | ret = -EEXIST; |
2494 | goto out; | |
1da177e4 | 2495 | } |
1c3d85dd | 2496 | cpufreq_driver = driver_data; |
0d1857a1 | 2497 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2498 | |
bc68b7df VK |
2499 | if (driver_data->setpolicy) |
2500 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2501 | ||
7a6c79f2 RW |
2502 | if (cpufreq_boost_supported()) { |
2503 | ret = create_boost_sysfs_file(); | |
2504 | if (ret) | |
2505 | goto err_null_driver; | |
2506 | } | |
6f19efc0 | 2507 | |
8a25a2fd | 2508 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2509 | if (ret) |
6f19efc0 | 2510 | goto err_boost_unreg; |
1da177e4 | 2511 | |
ce1bcfe9 VK |
2512 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2513 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2514 | /* if all ->init() calls failed, unregister */ |
ce1bcfe9 VK |
2515 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2516 | driver_data->name); | |
2517 | goto err_if_unreg; | |
1da177e4 LT |
2518 | } |
2519 | ||
8f5bc2ab | 2520 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2521 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2522 | goto out; |
fdd320da | 2523 | |
8a25a2fd KS |
2524 | err_if_unreg: |
2525 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2526 | err_boost_unreg: |
44139ed4 | 2527 | remove_boost_sysfs_file(); |
8f5bc2ab | 2528 | err_null_driver: |
0d1857a1 | 2529 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2530 | cpufreq_driver = NULL; |
0d1857a1 | 2531 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 PG |
2532 | out: |
2533 | put_online_cpus(); | |
2534 | return ret; | |
1da177e4 LT |
2535 | } |
2536 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2537 | ||
1da177e4 LT |
2538 | /** |
2539 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2540 | * | |
bb176f7d | 2541 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2542 | * the right to do so, i.e. if you have succeeded in initialising before! |
2543 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2544 | * currently not initialised. | |
2545 | */ | |
221dee28 | 2546 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2547 | { |
2548 | unsigned long flags; | |
2549 | ||
1c3d85dd | 2550 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2551 | return -EINVAL; |
1da177e4 | 2552 | |
2d06d8c4 | 2553 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2554 | |
454d3a25 SAS |
2555 | /* Protect against concurrent cpu hotplug */ |
2556 | get_online_cpus(); | |
8a25a2fd | 2557 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2558 | remove_boost_sysfs_file(); |
65edc68c | 2559 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2560 | |
0d1857a1 | 2561 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2562 | |
1c3d85dd | 2563 | cpufreq_driver = NULL; |
6eed9404 | 2564 | |
0d1857a1 | 2565 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
454d3a25 | 2566 | put_online_cpus(); |
1da177e4 LT |
2567 | |
2568 | return 0; | |
2569 | } | |
2570 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2571 | |
90de2a4a DA |
2572 | /* |
2573 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2574 | * or mutexes when secondary CPUs are halted. | |
2575 | */ | |
2576 | static struct syscore_ops cpufreq_syscore_ops = { | |
2577 | .shutdown = cpufreq_suspend, | |
2578 | }; | |
2579 | ||
c82bd444 VK |
2580 | struct kobject *cpufreq_global_kobject; |
2581 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2582 | ||
5a01f2e8 VP |
2583 | static int __init cpufreq_core_init(void) |
2584 | { | |
a7b422cd KRW |
2585 | if (cpufreq_disabled()) |
2586 | return -ENODEV; | |
2587 | ||
8eec1020 | 2588 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2589 | BUG_ON(!cpufreq_global_kobject); |
2590 | ||
90de2a4a DA |
2591 | register_syscore_ops(&cpufreq_syscore_ops); |
2592 | ||
5a01f2e8 VP |
2593 | return 0; |
2594 | } | |
5a01f2e8 | 2595 | core_initcall(cpufreq_core_init); |