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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
2f0aea93 | 29 | #include <linux/suspend.h> |
90de2a4a | 30 | #include <linux/syscore_ops.h> |
5ff0a268 | 31 | #include <linux/tick.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
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 | ||
7fb1327e | 135 | cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); |
72a4ce34 VK |
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) | |
7fb1327e | 146 | *wall = div_u64(cur_wall_time, NSEC_PER_USEC); |
72a4ce34 | 147 | |
7fb1327e | 148 | return div_u64(idle_time, NSEC_PER_USEC); |
72a4ce34 VK |
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 | |
aa7519af VK |
527 | unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) |
528 | { | |
529 | unsigned int latency; | |
530 | ||
531 | if (policy->transition_delay_us) | |
532 | return policy->transition_delay_us; | |
533 | ||
534 | latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; | |
535 | if (latency) | |
536 | return latency * LATENCY_MULTIPLIER; | |
537 | ||
538 | return LATENCY_MULTIPLIER; | |
539 | } | |
540 | EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); | |
541 | ||
1da177e4 LT |
542 | /********************************************************************* |
543 | * SYSFS INTERFACE * | |
544 | *********************************************************************/ | |
8a5c74a1 | 545 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
546 | struct attribute *attr, char *buf) |
547 | { | |
548 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
549 | } | |
550 | ||
551 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
552 | const char *buf, size_t count) | |
553 | { | |
554 | int ret, enable; | |
555 | ||
556 | ret = sscanf(buf, "%d", &enable); | |
557 | if (ret != 1 || enable < 0 || enable > 1) | |
558 | return -EINVAL; | |
559 | ||
560 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
561 | pr_err("%s: Cannot %s BOOST!\n", |
562 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
563 | return -EINVAL; |
564 | } | |
565 | ||
e837f9b5 JP |
566 | pr_debug("%s: cpufreq BOOST %s\n", |
567 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
568 | |
569 | return count; | |
570 | } | |
571 | define_one_global_rw(boost); | |
1da177e4 | 572 | |
42f91fa1 | 573 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
574 | { |
575 | struct cpufreq_governor *t; | |
576 | ||
f7b27061 | 577 | for_each_governor(t) |
7c4f4539 | 578 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
579 | return t; |
580 | ||
581 | return NULL; | |
582 | } | |
583 | ||
1da177e4 LT |
584 | /** |
585 | * cpufreq_parse_governor - parse a governor string | |
586 | */ | |
905d77cd | 587 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
588 | struct cpufreq_governor **governor) |
589 | { | |
3bcb09a3 | 590 | int err = -EINVAL; |
1c3d85dd | 591 | |
1c3d85dd | 592 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 593 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 594 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 595 | err = 0; |
7c4f4539 | 596 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 597 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 598 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 599 | err = 0; |
1da177e4 | 600 | } |
2e1cc3a5 | 601 | } else { |
1da177e4 | 602 | struct cpufreq_governor *t; |
3bcb09a3 | 603 | |
3fc54d37 | 604 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 605 | |
42f91fa1 | 606 | t = find_governor(str_governor); |
3bcb09a3 | 607 | |
ea714970 | 608 | if (t == NULL) { |
1a8e1463 | 609 | int ret; |
ea714970 | 610 | |
1a8e1463 KC |
611 | mutex_unlock(&cpufreq_governor_mutex); |
612 | ret = request_module("cpufreq_%s", str_governor); | |
613 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 614 | |
1a8e1463 | 615 | if (ret == 0) |
42f91fa1 | 616 | t = find_governor(str_governor); |
ea714970 JF |
617 | } |
618 | ||
3bcb09a3 JF |
619 | if (t != NULL) { |
620 | *governor = t; | |
621 | err = 0; | |
1da177e4 | 622 | } |
3bcb09a3 | 623 | |
3fc54d37 | 624 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 625 | } |
3bcb09a3 | 626 | return err; |
1da177e4 | 627 | } |
1da177e4 | 628 | |
1da177e4 | 629 | /** |
e08f5f5b GS |
630 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
631 | * print out cpufreq information | |
1da177e4 LT |
632 | * |
633 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
634 | * "unsigned int". | |
635 | */ | |
636 | ||
32ee8c3e DJ |
637 | #define show_one(file_name, object) \ |
638 | static ssize_t show_##file_name \ | |
905d77cd | 639 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 640 | { \ |
29464f28 | 641 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
642 | } |
643 | ||
644 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
645 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 646 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
647 | show_one(scaling_min_freq, min); |
648 | show_one(scaling_max_freq, max); | |
c034b02e | 649 | |
f8475cef LB |
650 | __weak unsigned int arch_freq_get_on_cpu(int cpu) |
651 | { | |
652 | return 0; | |
653 | } | |
654 | ||
09347b29 | 655 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
656 | { |
657 | ssize_t ret; | |
f8475cef | 658 | unsigned int freq; |
c034b02e | 659 | |
f8475cef LB |
660 | freq = arch_freq_get_on_cpu(policy->cpu); |
661 | if (freq) | |
662 | ret = sprintf(buf, "%u\n", freq); | |
663 | else if (cpufreq_driver && cpufreq_driver->setpolicy && | |
664 | cpufreq_driver->get) | |
c034b02e DB |
665 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); |
666 | else | |
667 | ret = sprintf(buf, "%u\n", policy->cur); | |
668 | return ret; | |
669 | } | |
1da177e4 | 670 | |
037ce839 | 671 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 672 | struct cpufreq_policy *new_policy); |
7970e08b | 673 | |
1da177e4 LT |
674 | /** |
675 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
676 | */ | |
677 | #define store_one(file_name, object) \ | |
678 | static ssize_t store_##file_name \ | |
905d77cd | 679 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 680 | { \ |
619c144c | 681 | int ret, temp; \ |
1da177e4 LT |
682 | struct cpufreq_policy new_policy; \ |
683 | \ | |
8fa5b631 | 684 | memcpy(&new_policy, policy, sizeof(*policy)); \ |
1da177e4 | 685 | \ |
29464f28 | 686 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
687 | if (ret != 1) \ |
688 | return -EINVAL; \ | |
689 | \ | |
619c144c | 690 | temp = new_policy.object; \ |
037ce839 | 691 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
692 | if (!ret) \ |
693 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
694 | \ |
695 | return ret ? ret : count; \ | |
696 | } | |
697 | ||
29464f28 DJ |
698 | store_one(scaling_min_freq, min); |
699 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
700 | |
701 | /** | |
702 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
703 | */ | |
905d77cd DJ |
704 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
705 | char *buf) | |
1da177e4 | 706 | { |
d92d50a4 | 707 | unsigned int cur_freq = __cpufreq_get(policy); |
9b4f603e RW |
708 | |
709 | if (cur_freq) | |
710 | return sprintf(buf, "%u\n", cur_freq); | |
711 | ||
712 | return sprintf(buf, "<unknown>\n"); | |
1da177e4 LT |
713 | } |
714 | ||
1da177e4 LT |
715 | /** |
716 | * show_scaling_governor - show the current policy for the specified CPU | |
717 | */ | |
905d77cd | 718 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 719 | { |
29464f28 | 720 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
721 | return sprintf(buf, "powersave\n"); |
722 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
723 | return sprintf(buf, "performance\n"); | |
724 | else if (policy->governor) | |
4b972f0b | 725 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 726 | policy->governor->name); |
1da177e4 LT |
727 | return -EINVAL; |
728 | } | |
729 | ||
1da177e4 LT |
730 | /** |
731 | * store_scaling_governor - store policy for the specified CPU | |
732 | */ | |
905d77cd DJ |
733 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
734 | const char *buf, size_t count) | |
1da177e4 | 735 | { |
5136fa56 | 736 | int ret; |
1da177e4 LT |
737 | char str_governor[16]; |
738 | struct cpufreq_policy new_policy; | |
739 | ||
8fa5b631 | 740 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 741 | |
29464f28 | 742 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
743 | if (ret != 1) |
744 | return -EINVAL; | |
745 | ||
e08f5f5b GS |
746 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
747 | &new_policy.governor)) | |
1da177e4 LT |
748 | return -EINVAL; |
749 | ||
037ce839 | 750 | ret = cpufreq_set_policy(policy, &new_policy); |
88dc4384 | 751 | return ret ? ret : count; |
1da177e4 LT |
752 | } |
753 | ||
754 | /** | |
755 | * show_scaling_driver - show the cpufreq driver currently loaded | |
756 | */ | |
905d77cd | 757 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 758 | { |
1c3d85dd | 759 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
760 | } |
761 | ||
762 | /** | |
763 | * show_scaling_available_governors - show the available CPUfreq governors | |
764 | */ | |
905d77cd DJ |
765 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
766 | char *buf) | |
1da177e4 LT |
767 | { |
768 | ssize_t i = 0; | |
769 | struct cpufreq_governor *t; | |
770 | ||
9c0ebcf7 | 771 | if (!has_target()) { |
1da177e4 LT |
772 | i += sprintf(buf, "performance powersave"); |
773 | goto out; | |
774 | } | |
775 | ||
f7b27061 | 776 | for_each_governor(t) { |
29464f28 DJ |
777 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
778 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 779 | goto out; |
4b972f0b | 780 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 781 | } |
7d5e350f | 782 | out: |
1da177e4 LT |
783 | i += sprintf(&buf[i], "\n"); |
784 | return i; | |
785 | } | |
e8628dd0 | 786 | |
f4fd3797 | 787 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
788 | { |
789 | ssize_t i = 0; | |
790 | unsigned int cpu; | |
791 | ||
835481d9 | 792 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
793 | if (i) |
794 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
795 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
796 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 797 | break; |
1da177e4 LT |
798 | } |
799 | i += sprintf(&buf[i], "\n"); | |
800 | return i; | |
801 | } | |
f4fd3797 | 802 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 803 | |
e8628dd0 DW |
804 | /** |
805 | * show_related_cpus - show the CPUs affected by each transition even if | |
806 | * hw coordination is in use | |
807 | */ | |
808 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
809 | { | |
f4fd3797 | 810 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
811 | } |
812 | ||
813 | /** | |
814 | * show_affected_cpus - show the CPUs affected by each transition | |
815 | */ | |
816 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
817 | { | |
f4fd3797 | 818 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
819 | } |
820 | ||
9e76988e | 821 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 822 | const char *buf, size_t count) |
9e76988e VP |
823 | { |
824 | unsigned int freq = 0; | |
825 | unsigned int ret; | |
826 | ||
879000f9 | 827 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
828 | return -EINVAL; |
829 | ||
830 | ret = sscanf(buf, "%u", &freq); | |
831 | if (ret != 1) | |
832 | return -EINVAL; | |
833 | ||
834 | policy->governor->store_setspeed(policy, freq); | |
835 | ||
836 | return count; | |
837 | } | |
838 | ||
839 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
840 | { | |
879000f9 | 841 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
842 | return sprintf(buf, "<unsupported>\n"); |
843 | ||
844 | return policy->governor->show_setspeed(policy, buf); | |
845 | } | |
1da177e4 | 846 | |
e2f74f35 | 847 | /** |
8bf1ac72 | 848 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
849 | */ |
850 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
851 | { | |
852 | unsigned int limit; | |
853 | int ret; | |
1c3d85dd RW |
854 | if (cpufreq_driver->bios_limit) { |
855 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
856 | if (!ret) |
857 | return sprintf(buf, "%u\n", limit); | |
858 | } | |
859 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
860 | } | |
861 | ||
6dad2a29 BP |
862 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
863 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
864 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
865 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
866 | cpufreq_freq_attr_ro(scaling_available_governors); | |
867 | cpufreq_freq_attr_ro(scaling_driver); | |
868 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
869 | cpufreq_freq_attr_ro(bios_limit); | |
870 | cpufreq_freq_attr_ro(related_cpus); | |
871 | cpufreq_freq_attr_ro(affected_cpus); | |
872 | cpufreq_freq_attr_rw(scaling_min_freq); | |
873 | cpufreq_freq_attr_rw(scaling_max_freq); | |
874 | cpufreq_freq_attr_rw(scaling_governor); | |
875 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 876 | |
905d77cd | 877 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
878 | &cpuinfo_min_freq.attr, |
879 | &cpuinfo_max_freq.attr, | |
ed129784 | 880 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
881 | &scaling_min_freq.attr, |
882 | &scaling_max_freq.attr, | |
883 | &affected_cpus.attr, | |
e8628dd0 | 884 | &related_cpus.attr, |
1da177e4 LT |
885 | &scaling_governor.attr, |
886 | &scaling_driver.attr, | |
887 | &scaling_available_governors.attr, | |
9e76988e | 888 | &scaling_setspeed.attr, |
1da177e4 LT |
889 | NULL |
890 | }; | |
891 | ||
29464f28 DJ |
892 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
893 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 894 | |
29464f28 | 895 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 896 | { |
905d77cd DJ |
897 | struct cpufreq_policy *policy = to_policy(kobj); |
898 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 899 | ssize_t ret; |
6eed9404 | 900 | |
ad7722da | 901 | down_read(&policy->rwsem); |
6541aef0 | 902 | ret = fattr->show(policy, buf); |
ad7722da | 903 | up_read(&policy->rwsem); |
1b750e3b | 904 | |
1da177e4 LT |
905 | return ret; |
906 | } | |
907 | ||
905d77cd DJ |
908 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
909 | const char *buf, size_t count) | |
1da177e4 | 910 | { |
905d77cd DJ |
911 | struct cpufreq_policy *policy = to_policy(kobj); |
912 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 913 | ssize_t ret = -EINVAL; |
6eed9404 | 914 | |
a92551e4 | 915 | cpus_read_lock(); |
4f750c93 | 916 | |
6541aef0 RW |
917 | if (cpu_online(policy->cpu)) { |
918 | down_write(&policy->rwsem); | |
e08f5f5b | 919 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
920 | up_write(&policy->rwsem); |
921 | } | |
e08f5f5b | 922 | |
a92551e4 | 923 | cpus_read_unlock(); |
4f750c93 | 924 | |
1da177e4 LT |
925 | return ret; |
926 | } | |
927 | ||
905d77cd | 928 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 929 | { |
905d77cd | 930 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 931 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
932 | complete(&policy->kobj_unregister); |
933 | } | |
934 | ||
52cf25d0 | 935 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
936 | .show = show, |
937 | .store = store, | |
938 | }; | |
939 | ||
940 | static struct kobj_type ktype_cpufreq = { | |
941 | .sysfs_ops = &sysfs_ops, | |
942 | .default_attrs = default_attrs, | |
943 | .release = cpufreq_sysfs_release, | |
944 | }; | |
945 | ||
2f0ba790 | 946 | static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) |
87549141 | 947 | { |
2f0ba790 RW |
948 | struct device *dev = get_cpu_device(cpu); |
949 | ||
950 | if (!dev) | |
951 | return; | |
952 | ||
953 | if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) | |
954 | return; | |
955 | ||
26619804 | 956 | dev_dbg(dev, "%s: Adding symlink\n", __func__); |
2f0ba790 RW |
957 | if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) |
958 | dev_err(dev, "cpufreq symlink creation failed\n"); | |
87549141 VK |
959 | } |
960 | ||
26619804 VK |
961 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, |
962 | struct device *dev) | |
87549141 | 963 | { |
26619804 VK |
964 | dev_dbg(dev, "%s: Removing symlink\n", __func__); |
965 | sysfs_remove_link(&dev->kobj, "cpufreq"); | |
87549141 VK |
966 | } |
967 | ||
d9612a49 | 968 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
969 | { |
970 | struct freq_attr **drv_attr; | |
909a694e | 971 | int ret = 0; |
909a694e | 972 | |
909a694e | 973 | /* set up files for this cpu device */ |
1c3d85dd | 974 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 975 | while (drv_attr && *drv_attr) { |
909a694e DJ |
976 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
977 | if (ret) | |
6d4e81ed | 978 | return ret; |
909a694e DJ |
979 | drv_attr++; |
980 | } | |
1c3d85dd | 981 | if (cpufreq_driver->get) { |
909a694e DJ |
982 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
983 | if (ret) | |
6d4e81ed | 984 | return ret; |
909a694e | 985 | } |
c034b02e DB |
986 | |
987 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
988 | if (ret) | |
6d4e81ed | 989 | return ret; |
c034b02e | 990 | |
1c3d85dd | 991 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
992 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
993 | if (ret) | |
6d4e81ed | 994 | return ret; |
e2f74f35 | 995 | } |
909a694e | 996 | |
26619804 | 997 | return 0; |
e18f1682 SB |
998 | } |
999 | ||
de1df26b RW |
1000 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
1001 | { | |
1002 | return NULL; | |
1003 | } | |
1004 | ||
7f0fa40f | 1005 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 1006 | { |
6e2c89d1 | 1007 | struct cpufreq_governor *gov = NULL; |
e18f1682 | 1008 | struct cpufreq_policy new_policy; |
e18f1682 | 1009 | |
d5b73cd8 | 1010 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 1011 | |
6e2c89d1 | 1012 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 1013 | gov = find_governor(policy->last_governor); |
de1df26b | 1014 | if (gov) { |
6e2c89d1 | 1015 | pr_debug("Restoring governor %s for cpu %d\n", |
1016 | policy->governor->name, policy->cpu); | |
de1df26b RW |
1017 | } else { |
1018 | gov = cpufreq_default_governor(); | |
1019 | if (!gov) | |
1020 | return -ENODATA; | |
1021 | } | |
6e2c89d1 | 1022 | |
1023 | new_policy.governor = gov; | |
1024 | ||
69030dd1 SP |
1025 | /* Use the default policy if there is no last_policy. */ |
1026 | if (cpufreq_driver->setpolicy) { | |
1027 | if (policy->last_policy) | |
1028 | new_policy.policy = policy->last_policy; | |
1029 | else | |
1030 | cpufreq_parse_governor(gov->name, &new_policy.policy, | |
1031 | NULL); | |
1032 | } | |
ecf7e461 | 1033 | /* set default policy */ |
7f0fa40f | 1034 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
1035 | } |
1036 | ||
d9612a49 | 1037 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 1038 | { |
9c0ebcf7 | 1039 | int ret = 0; |
fcf80582 | 1040 | |
bb29ae15 VK |
1041 | /* Has this CPU been taken care of already? */ |
1042 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1043 | return 0; | |
1044 | ||
49f18560 | 1045 | down_write(&policy->rwsem); |
45482c70 RW |
1046 | if (has_target()) |
1047 | cpufreq_stop_governor(policy); | |
fcf80582 | 1048 | |
fcf80582 | 1049 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 1050 | |
9c0ebcf7 | 1051 | if (has_target()) { |
0a300767 | 1052 | ret = cpufreq_start_governor(policy); |
49f18560 | 1053 | if (ret) |
3de9bdeb | 1054 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 1055 | } |
49f18560 VK |
1056 | up_write(&policy->rwsem); |
1057 | return ret; | |
fcf80582 | 1058 | } |
1da177e4 | 1059 | |
11eb69b9 VK |
1060 | static void handle_update(struct work_struct *work) |
1061 | { | |
1062 | struct cpufreq_policy *policy = | |
1063 | container_of(work, struct cpufreq_policy, update); | |
1064 | unsigned int cpu = policy->cpu; | |
1065 | pr_debug("handle_update for cpu %u called\n", cpu); | |
1066 | cpufreq_update_policy(cpu); | |
fcf80582 | 1067 | } |
1da177e4 | 1068 | |
a34e63b1 | 1069 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 SB |
1070 | { |
1071 | struct cpufreq_policy *policy; | |
edd4a893 | 1072 | int ret; |
e9698cc5 SB |
1073 | |
1074 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); | |
1075 | if (!policy) | |
1076 | return NULL; | |
1077 | ||
1078 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1079 | goto err_free_policy; | |
1080 | ||
1081 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1082 | goto err_free_cpumask; | |
1083 | ||
559ed407 RW |
1084 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1085 | goto err_free_rcpumask; | |
1086 | ||
edd4a893 VK |
1087 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1088 | cpufreq_global_kobject, "policy%u", cpu); | |
1089 | if (ret) { | |
1090 | pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); | |
1091 | goto err_free_real_cpus; | |
1092 | } | |
1093 | ||
c88a1f8b | 1094 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1095 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1096 | spin_lock_init(&policy->transition_lock); |
1097 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1098 | init_completion(&policy->kobj_unregister); |
1099 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1100 | |
a34e63b1 | 1101 | policy->cpu = cpu; |
e9698cc5 SB |
1102 | return policy; |
1103 | ||
edd4a893 VK |
1104 | err_free_real_cpus: |
1105 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1106 | err_free_rcpumask: |
1107 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1108 | err_free_cpumask: |
1109 | free_cpumask_var(policy->cpus); | |
1110 | err_free_policy: | |
1111 | kfree(policy); | |
1112 | ||
1113 | return NULL; | |
1114 | } | |
1115 | ||
f9f41e3e | 1116 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) |
42f921a6 VK |
1117 | { |
1118 | struct kobject *kobj; | |
1119 | struct completion *cmp; | |
1120 | ||
87549141 | 1121 | down_write(&policy->rwsem); |
1aefc75b | 1122 | cpufreq_stats_free_table(policy); |
42f921a6 VK |
1123 | kobj = &policy->kobj; |
1124 | cmp = &policy->kobj_unregister; | |
87549141 | 1125 | up_write(&policy->rwsem); |
42f921a6 VK |
1126 | kobject_put(kobj); |
1127 | ||
1128 | /* | |
1129 | * We need to make sure that the underlying kobj is | |
1130 | * actually not referenced anymore by anybody before we | |
1131 | * proceed with unloading. | |
1132 | */ | |
1133 | pr_debug("waiting for dropping of refcount\n"); | |
1134 | wait_for_completion(cmp); | |
1135 | pr_debug("wait complete\n"); | |
1136 | } | |
1137 | ||
f9f41e3e | 1138 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
e9698cc5 | 1139 | { |
988bed09 VK |
1140 | unsigned long flags; |
1141 | int cpu; | |
1142 | ||
1143 | /* Remove policy from list */ | |
1144 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1145 | list_del(&policy->policy_list); | |
1146 | ||
1147 | for_each_cpu(cpu, policy->related_cpus) | |
1148 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1149 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1150 | ||
f9f41e3e | 1151 | cpufreq_policy_put_kobj(policy); |
559ed407 | 1152 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1153 | free_cpumask_var(policy->related_cpus); |
1154 | free_cpumask_var(policy->cpus); | |
1155 | kfree(policy); | |
1156 | } | |
1157 | ||
0b275352 | 1158 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1159 | { |
7f0c020a | 1160 | struct cpufreq_policy *policy; |
194d99c7 | 1161 | bool new_policy; |
1da177e4 | 1162 | unsigned long flags; |
0b275352 RW |
1163 | unsigned int j; |
1164 | int ret; | |
87549141 | 1165 | |
0b275352 | 1166 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1167 | |
bb29ae15 | 1168 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1169 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1170 | if (policy) { |
9104bb26 | 1171 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1172 | if (!policy_is_inactive(policy)) |
d9612a49 | 1173 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1174 | |
11ce707e | 1175 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1176 | new_policy = false; |
11ce707e RW |
1177 | down_write(&policy->rwsem); |
1178 | policy->cpu = cpu; | |
1179 | policy->governor = NULL; | |
1180 | up_write(&policy->rwsem); | |
1181 | } else { | |
194d99c7 | 1182 | new_policy = true; |
a34e63b1 | 1183 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1184 | if (!policy) |
d4d854d6 | 1185 | return -ENOMEM; |
72368d12 | 1186 | } |
0d66b91e | 1187 | |
835481d9 | 1188 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1189 | |
1da177e4 LT |
1190 | /* call driver. From then on the cpufreq must be able |
1191 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1192 | */ | |
1c3d85dd | 1193 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1194 | if (ret) { |
2d06d8c4 | 1195 | pr_debug("initialization failed\n"); |
8101f997 | 1196 | goto out_free_policy; |
1da177e4 | 1197 | } |
643ae6e8 | 1198 | |
6d4e81ed TV |
1199 | down_write(&policy->rwsem); |
1200 | ||
194d99c7 | 1201 | if (new_policy) { |
4d1f3a5b | 1202 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1203 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1204 | } |
559ed407 | 1205 | |
5a7e56a5 VK |
1206 | /* |
1207 | * affected cpus must always be the one, which are online. We aren't | |
1208 | * managing offline cpus here. | |
1209 | */ | |
1210 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1211 | ||
194d99c7 | 1212 | if (new_policy) { |
5a7e56a5 VK |
1213 | policy->user_policy.min = policy->min; |
1214 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1215 | |
2f0ba790 | 1216 | for_each_cpu(j, policy->related_cpus) { |
988bed09 | 1217 | per_cpu(cpufreq_cpu_data, j) = policy; |
2f0ba790 RW |
1218 | add_cpu_dev_symlink(policy, j); |
1219 | } | |
ff010472 VK |
1220 | } else { |
1221 | policy->min = policy->user_policy.min; | |
1222 | policy->max = policy->user_policy.max; | |
988bed09 | 1223 | } |
652ed95d | 1224 | |
2ed99e39 | 1225 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1226 | policy->cur = cpufreq_driver->get(policy->cpu); |
1227 | if (!policy->cur) { | |
1228 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1229 | goto out_exit_policy; |
da60ce9f VK |
1230 | } |
1231 | } | |
1232 | ||
d3916691 VK |
1233 | /* |
1234 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1235 | * frequency table present with cpufreq core. In such cases CPU might be | |
1236 | * unstable if it has to run on that frequency for long duration of time | |
1237 | * and so its better to set it to a frequency which is specified in | |
1238 | * freq-table. This also makes cpufreq stats inconsistent as | |
1239 | * cpufreq-stats would fail to register because current frequency of CPU | |
1240 | * isn't found in freq-table. | |
1241 | * | |
1242 | * Because we don't want this change to effect boot process badly, we go | |
1243 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1244 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1245 | * is initialized to zero). | |
1246 | * | |
1247 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1248 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1249 | * equal to target-freq. | |
1250 | */ | |
1251 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1252 | && has_target()) { | |
1253 | /* Are we running at unknown frequency ? */ | |
1254 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1255 | if (ret == -EINVAL) { | |
1256 | /* Warn user and fix it */ | |
1257 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1258 | __func__, policy->cpu, policy->cur); | |
1259 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1260 | CPUFREQ_RELATION_L); | |
1261 | ||
1262 | /* | |
1263 | * Reaching here after boot in a few seconds may not | |
1264 | * mean that system will remain stable at "unknown" | |
1265 | * frequency for longer duration. Hence, a BUG_ON(). | |
1266 | */ | |
1267 | BUG_ON(ret); | |
1268 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1269 | __func__, policy->cpu, policy->cur); | |
1270 | } | |
1271 | } | |
1272 | ||
194d99c7 | 1273 | if (new_policy) { |
d9612a49 | 1274 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1275 | if (ret) |
8101f997 | 1276 | goto out_exit_policy; |
1aefc75b RW |
1277 | |
1278 | cpufreq_stats_create_table(policy); | |
8ff69732 | 1279 | |
988bed09 VK |
1280 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1281 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1282 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1283 | } | |
9515f4d6 | 1284 | |
7f0fa40f VK |
1285 | ret = cpufreq_init_policy(policy); |
1286 | if (ret) { | |
1287 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1288 | __func__, cpu, ret); | |
194d99c7 RW |
1289 | /* cpufreq_policy_free() will notify based on this */ |
1290 | new_policy = false; | |
1291 | goto out_exit_policy; | |
08fd8c1c | 1292 | } |
e18f1682 | 1293 | |
4e97b631 | 1294 | up_write(&policy->rwsem); |
08fd8c1c | 1295 | |
038c5b3e | 1296 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1297 | |
7c45cf31 VK |
1298 | /* Callback for handling stuff after policy is ready */ |
1299 | if (cpufreq_driver->ready) | |
1300 | cpufreq_driver->ready(policy); | |
1301 | ||
2d06d8c4 | 1302 | pr_debug("initialization complete\n"); |
87c32271 | 1303 | |
1da177e4 LT |
1304 | return 0; |
1305 | ||
8101f997 | 1306 | out_exit_policy: |
7106e02b PB |
1307 | up_write(&policy->rwsem); |
1308 | ||
da60ce9f VK |
1309 | if (cpufreq_driver->exit) |
1310 | cpufreq_driver->exit(policy); | |
2f0ba790 RW |
1311 | |
1312 | for_each_cpu(j, policy->real_cpus) | |
1313 | remove_cpu_dev_symlink(policy, get_cpu_device(j)); | |
1314 | ||
8101f997 | 1315 | out_free_policy: |
f9f41e3e | 1316 | cpufreq_policy_free(policy); |
1da177e4 LT |
1317 | return ret; |
1318 | } | |
1319 | ||
0b275352 RW |
1320 | /** |
1321 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1322 | * @dev: CPU device. | |
1323 | * @sif: Subsystem interface structure pointer (not used) | |
1324 | */ | |
1325 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1326 | { | |
a794d613 | 1327 | struct cpufreq_policy *policy; |
0b275352 | 1328 | unsigned cpu = dev->id; |
26619804 | 1329 | int ret; |
0b275352 RW |
1330 | |
1331 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1332 | ||
26619804 VK |
1333 | if (cpu_online(cpu)) { |
1334 | ret = cpufreq_online(cpu); | |
1335 | if (ret) | |
1336 | return ret; | |
1337 | } | |
0b275352 | 1338 | |
26619804 | 1339 | /* Create sysfs link on CPU registration */ |
a794d613 | 1340 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2f0ba790 RW |
1341 | if (policy) |
1342 | add_cpu_dev_symlink(policy, cpu); | |
26619804 | 1343 | |
2f0ba790 | 1344 | return 0; |
1da177e4 LT |
1345 | } |
1346 | ||
27622b06 | 1347 | static int cpufreq_offline(unsigned int cpu) |
1da177e4 | 1348 | { |
3a3e9e06 | 1349 | struct cpufreq_policy *policy; |
69cee714 | 1350 | int ret; |
1da177e4 | 1351 | |
b8eed8af | 1352 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1353 | |
988bed09 | 1354 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1355 | if (!policy) { |
b8eed8af | 1356 | pr_debug("%s: No cpu_data found\n", __func__); |
27622b06 | 1357 | return 0; |
1da177e4 | 1358 | } |
1da177e4 | 1359 | |
49f18560 | 1360 | down_write(&policy->rwsem); |
45482c70 RW |
1361 | if (has_target()) |
1362 | cpufreq_stop_governor(policy); | |
1da177e4 | 1363 | |
9591becb | 1364 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1365 | |
9591becb VK |
1366 | if (policy_is_inactive(policy)) { |
1367 | if (has_target()) | |
1368 | strncpy(policy->last_governor, policy->governor->name, | |
1369 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1370 | else |
1371 | policy->last_policy = policy->policy; | |
9591becb VK |
1372 | } else if (cpu == policy->cpu) { |
1373 | /* Nominate new CPU */ | |
1374 | policy->cpu = cpumask_any(policy->cpus); | |
1375 | } | |
084f3493 | 1376 | |
9591becb VK |
1377 | /* Start governor again for active policy */ |
1378 | if (!policy_is_inactive(policy)) { | |
1379 | if (has_target()) { | |
0a300767 | 1380 | ret = cpufreq_start_governor(policy); |
9591becb VK |
1381 | if (ret) |
1382 | pr_err("%s: Failed to start governor\n", __func__); | |
1383 | } | |
cedb70af | 1384 | |
49f18560 | 1385 | goto unlock; |
cedb70af SB |
1386 | } |
1387 | ||
69cee714 VK |
1388 | if (cpufreq_driver->stop_cpu) |
1389 | cpufreq_driver->stop_cpu(policy); | |
87549141 | 1390 | |
36be3418 RW |
1391 | if (has_target()) |
1392 | cpufreq_exit_governor(policy); | |
1da177e4 | 1393 | |
87549141 VK |
1394 | /* |
1395 | * Perform the ->exit() even during light-weight tear-down, | |
1396 | * since this is a core component, and is essential for the | |
1397 | * subsequent light-weight ->init() to succeed. | |
1398 | */ | |
55582bcc | 1399 | if (cpufreq_driver->exit) { |
87549141 | 1400 | cpufreq_driver->exit(policy); |
55582bcc SP |
1401 | policy->freq_table = NULL; |
1402 | } | |
49f18560 VK |
1403 | |
1404 | unlock: | |
1405 | up_write(&policy->rwsem); | |
27622b06 | 1406 | return 0; |
1da177e4 LT |
1407 | } |
1408 | ||
cedb70af | 1409 | /** |
27a862e9 | 1410 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1411 | * |
1412 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1413 | */ |
71db87ba | 1414 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1415 | { |
8a25a2fd | 1416 | unsigned int cpu = dev->id; |
559ed407 | 1417 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1418 | |
559ed407 | 1419 | if (!policy) |
1af115d6 | 1420 | return; |
87549141 | 1421 | |
69cee714 VK |
1422 | if (cpu_online(cpu)) |
1423 | cpufreq_offline(cpu); | |
87549141 | 1424 | |
559ed407 | 1425 | cpumask_clear_cpu(cpu, policy->real_cpus); |
26619804 | 1426 | remove_cpu_dev_symlink(policy, dev); |
87549141 | 1427 | |
f344dae0 | 1428 | if (cpumask_empty(policy->real_cpus)) |
f9f41e3e | 1429 | cpufreq_policy_free(policy); |
5a01f2e8 VP |
1430 | } |
1431 | ||
1da177e4 | 1432 | /** |
bb176f7d VK |
1433 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1434 | * in deep trouble. | |
a1e1dc41 | 1435 | * @policy: policy managing CPUs |
1da177e4 LT |
1436 | * @new_freq: CPU frequency the CPU actually runs at |
1437 | * | |
29464f28 DJ |
1438 | * We adjust to current frequency first, and need to clean up later. |
1439 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1440 | */ |
a1e1dc41 | 1441 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1442 | unsigned int new_freq) |
1da177e4 LT |
1443 | { |
1444 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1445 | |
e837f9b5 | 1446 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1447 | policy->cur, new_freq); |
1da177e4 | 1448 | |
a1e1dc41 | 1449 | freqs.old = policy->cur; |
1da177e4 | 1450 | freqs.new = new_freq; |
b43a7ffb | 1451 | |
8fec051e VK |
1452 | cpufreq_freq_transition_begin(policy, &freqs); |
1453 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1454 | } |
1455 | ||
32ee8c3e | 1456 | /** |
4ab70df4 | 1457 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1458 | * @cpu: CPU number |
1459 | * | |
1460 | * This is the last known freq, without actually getting it from the driver. | |
1461 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1462 | */ | |
1463 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1464 | { | |
9e21ba8b | 1465 | struct cpufreq_policy *policy; |
e08f5f5b | 1466 | unsigned int ret_freq = 0; |
c75361c0 | 1467 | unsigned long flags; |
95235ca2 | 1468 | |
c75361c0 RC |
1469 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1470 | ||
1471 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { | |
1472 | ret_freq = cpufreq_driver->get(cpu); | |
1473 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1474 | return ret_freq; | |
1475 | } | |
1476 | ||
1477 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
9e21ba8b DB |
1478 | |
1479 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1480 | if (policy) { |
e08f5f5b | 1481 | ret_freq = policy->cur; |
95235ca2 VP |
1482 | cpufreq_cpu_put(policy); |
1483 | } | |
1484 | ||
4d34a67d | 1485 | return ret_freq; |
95235ca2 VP |
1486 | } |
1487 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1488 | ||
3d737108 JB |
1489 | /** |
1490 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1491 | * @cpu: CPU number | |
1492 | * | |
1493 | * Just return the max possible frequency for a given CPU. | |
1494 | */ | |
1495 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1496 | { | |
1497 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1498 | unsigned int ret_freq = 0; | |
1499 | ||
1500 | if (policy) { | |
1501 | ret_freq = policy->max; | |
1502 | cpufreq_cpu_put(policy); | |
1503 | } | |
1504 | ||
1505 | return ret_freq; | |
1506 | } | |
1507 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1508 | ||
d92d50a4 | 1509 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1510 | { |
e08f5f5b | 1511 | unsigned int ret_freq = 0; |
5800043b | 1512 | |
1c3d85dd | 1513 | if (!cpufreq_driver->get) |
4d34a67d | 1514 | return ret_freq; |
1da177e4 | 1515 | |
d92d50a4 | 1516 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1517 | |
b7898fda RW |
1518 | /* |
1519 | * Updating inactive policies is invalid, so avoid doing that. Also | |
1520 | * if fast frequency switching is used with the given policy, the check | |
1521 | * against policy->cur is pointless, so skip it in that case too. | |
1522 | */ | |
1523 | if (unlikely(policy_is_inactive(policy)) || policy->fast_switch_enabled) | |
11e584cf VK |
1524 | return ret_freq; |
1525 | ||
e08f5f5b | 1526 | if (ret_freq && policy->cur && |
1c3d85dd | 1527 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1528 | /* verify no discrepancy between actual and |
1529 | saved value exists */ | |
1530 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1531 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1532 | schedule_work(&policy->update); |
1533 | } | |
1534 | } | |
1535 | ||
4d34a67d | 1536 | return ret_freq; |
5a01f2e8 | 1537 | } |
1da177e4 | 1538 | |
5a01f2e8 VP |
1539 | /** |
1540 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1541 | * @cpu: CPU number | |
1542 | * | |
1543 | * Get the CPU current (static) CPU frequency | |
1544 | */ | |
1545 | unsigned int cpufreq_get(unsigned int cpu) | |
1546 | { | |
999976e0 | 1547 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1548 | unsigned int ret_freq = 0; |
5a01f2e8 | 1549 | |
999976e0 AP |
1550 | if (policy) { |
1551 | down_read(&policy->rwsem); | |
182e36af RW |
1552 | |
1553 | if (!policy_is_inactive(policy)) | |
1554 | ret_freq = __cpufreq_get(policy); | |
1555 | ||
999976e0 | 1556 | up_read(&policy->rwsem); |
5a01f2e8 | 1557 | |
999976e0 AP |
1558 | cpufreq_cpu_put(policy); |
1559 | } | |
6eed9404 | 1560 | |
4d34a67d | 1561 | return ret_freq; |
1da177e4 LT |
1562 | } |
1563 | EXPORT_SYMBOL(cpufreq_get); | |
1564 | ||
999f5729 RW |
1565 | static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy) |
1566 | { | |
1567 | unsigned int new_freq; | |
1568 | ||
1569 | new_freq = cpufreq_driver->get(policy->cpu); | |
1570 | if (!new_freq) | |
1571 | return 0; | |
1572 | ||
1573 | if (!policy->cur) { | |
1574 | pr_debug("cpufreq: Driver did not initialize current freq\n"); | |
1575 | policy->cur = new_freq; | |
1576 | } else if (policy->cur != new_freq && has_target()) { | |
1577 | cpufreq_out_of_sync(policy, new_freq); | |
1578 | } | |
1579 | ||
1580 | return new_freq; | |
1581 | } | |
1582 | ||
8a25a2fd KS |
1583 | static struct subsys_interface cpufreq_interface = { |
1584 | .name = "cpufreq", | |
1585 | .subsys = &cpu_subsys, | |
1586 | .add_dev = cpufreq_add_dev, | |
1587 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1588 | }; |
1589 | ||
e28867ea VK |
1590 | /* |
1591 | * In case platform wants some specific frequency to be configured | |
1592 | * during suspend.. | |
1593 | */ | |
1594 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1595 | { | |
1596 | int ret; | |
1597 | ||
1598 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1599 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1600 | return 0; | |
e28867ea VK |
1601 | } |
1602 | ||
1603 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1604 | policy->suspend_freq); | |
1605 | ||
1606 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1607 | CPUFREQ_RELATION_H); | |
1608 | if (ret) | |
1609 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1610 | __func__, policy->suspend_freq, ret); | |
1611 | ||
1612 | return ret; | |
1613 | } | |
1614 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1615 | ||
42d4dc3f | 1616 | /** |
2f0aea93 | 1617 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1618 | * |
2f0aea93 VK |
1619 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1620 | * as some platforms can't change frequency after this point in suspend cycle. | |
1621 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1622 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1623 | */ |
2f0aea93 | 1624 | void cpufreq_suspend(void) |
42d4dc3f | 1625 | { |
3a3e9e06 | 1626 | struct cpufreq_policy *policy; |
42d4dc3f | 1627 | |
2f0aea93 VK |
1628 | if (!cpufreq_driver) |
1629 | return; | |
42d4dc3f | 1630 | |
ba41e1bc | 1631 | if (!has_target() && !cpufreq_driver->suspend) |
b1b12bab | 1632 | goto suspend; |
42d4dc3f | 1633 | |
2f0aea93 VK |
1634 | pr_debug("%s: Suspending Governors\n", __func__); |
1635 | ||
f963735a | 1636 | for_each_active_policy(policy) { |
ba41e1bc RW |
1637 | if (has_target()) { |
1638 | down_write(&policy->rwsem); | |
45482c70 | 1639 | cpufreq_stop_governor(policy); |
ba41e1bc | 1640 | up_write(&policy->rwsem); |
ba41e1bc RW |
1641 | } |
1642 | ||
1643 | if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) | |
2f0aea93 VK |
1644 | pr_err("%s: Failed to suspend driver: %p\n", __func__, |
1645 | policy); | |
42d4dc3f | 1646 | } |
b1b12bab VK |
1647 | |
1648 | suspend: | |
1649 | cpufreq_suspended = true; | |
42d4dc3f BH |
1650 | } |
1651 | ||
1da177e4 | 1652 | /** |
2f0aea93 | 1653 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1654 | * |
2f0aea93 VK |
1655 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1656 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1657 | */ |
2f0aea93 | 1658 | void cpufreq_resume(void) |
1da177e4 | 1659 | { |
3a3e9e06 | 1660 | struct cpufreq_policy *policy; |
49f18560 | 1661 | int ret; |
1da177e4 | 1662 | |
2f0aea93 VK |
1663 | if (!cpufreq_driver) |
1664 | return; | |
1da177e4 | 1665 | |
8e30444e LT |
1666 | cpufreq_suspended = false; |
1667 | ||
ba41e1bc | 1668 | if (!has_target() && !cpufreq_driver->resume) |
e00e56df | 1669 | return; |
1da177e4 | 1670 | |
2f0aea93 | 1671 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1672 | |
f963735a | 1673 | for_each_active_policy(policy) { |
49f18560 | 1674 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1675 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1676 | policy); | |
ba41e1bc | 1677 | } else if (has_target()) { |
49f18560 | 1678 | down_write(&policy->rwsem); |
0a300767 | 1679 | ret = cpufreq_start_governor(policy); |
49f18560 VK |
1680 | up_write(&policy->rwsem); |
1681 | ||
1682 | if (ret) | |
1683 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1684 | __func__, policy); | |
1685 | } | |
2f0aea93 VK |
1686 | } |
1687 | } | |
1da177e4 | 1688 | |
9d95046e BP |
1689 | /** |
1690 | * cpufreq_get_current_driver - return current driver's name | |
1691 | * | |
1692 | * Return the name string of the currently loaded cpufreq driver | |
1693 | * or NULL, if none. | |
1694 | */ | |
1695 | const char *cpufreq_get_current_driver(void) | |
1696 | { | |
1c3d85dd RW |
1697 | if (cpufreq_driver) |
1698 | return cpufreq_driver->name; | |
1699 | ||
1700 | return NULL; | |
9d95046e BP |
1701 | } |
1702 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1703 | |
51315cdf TP |
1704 | /** |
1705 | * cpufreq_get_driver_data - return current driver data | |
1706 | * | |
1707 | * Return the private data of the currently loaded cpufreq | |
1708 | * driver, or NULL if no cpufreq driver is loaded. | |
1709 | */ | |
1710 | void *cpufreq_get_driver_data(void) | |
1711 | { | |
1712 | if (cpufreq_driver) | |
1713 | return cpufreq_driver->driver_data; | |
1714 | ||
1715 | return NULL; | |
1716 | } | |
1717 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1718 | ||
1da177e4 LT |
1719 | /********************************************************************* |
1720 | * NOTIFIER LISTS INTERFACE * | |
1721 | *********************************************************************/ | |
1722 | ||
1723 | /** | |
1724 | * cpufreq_register_notifier - register a driver with cpufreq | |
1725 | * @nb: notifier function to register | |
1726 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1727 | * | |
32ee8c3e | 1728 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1729 | * are notified about clock rate changes (once before and once after |
1730 | * the transition), or a list of drivers that are notified about | |
1731 | * changes in cpufreq policy. | |
1732 | * | |
1733 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1734 | * blocking_notifier_chain_register. |
1da177e4 LT |
1735 | */ |
1736 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1737 | { | |
1738 | int ret; | |
1739 | ||
d5aaffa9 DB |
1740 | if (cpufreq_disabled()) |
1741 | return -EINVAL; | |
1742 | ||
74212ca4 CEB |
1743 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1744 | ||
1da177e4 LT |
1745 | switch (list) { |
1746 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1747 | mutex_lock(&cpufreq_fast_switch_lock); |
1748 | ||
1749 | if (cpufreq_fast_switch_count > 0) { | |
1750 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1751 | return -EBUSY; | |
1752 | } | |
b4dfdbb3 | 1753 | ret = srcu_notifier_chain_register( |
e041c683 | 1754 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1755 | if (!ret) |
1756 | cpufreq_fast_switch_count--; | |
1757 | ||
1758 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1759 | break; |
1760 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1761 | ret = blocking_notifier_chain_register( |
1762 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1763 | break; |
1764 | default: | |
1765 | ret = -EINVAL; | |
1766 | } | |
1da177e4 LT |
1767 | |
1768 | return ret; | |
1769 | } | |
1770 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1771 | ||
1da177e4 LT |
1772 | /** |
1773 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1774 | * @nb: notifier block to be unregistered | |
bb176f7d | 1775 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1776 | * |
1777 | * Remove a driver from the CPU frequency notifier list. | |
1778 | * | |
1779 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1780 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1781 | */ |
1782 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1783 | { | |
1784 | int ret; | |
1785 | ||
d5aaffa9 DB |
1786 | if (cpufreq_disabled()) |
1787 | return -EINVAL; | |
1788 | ||
1da177e4 LT |
1789 | switch (list) { |
1790 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b7898fda RW |
1791 | mutex_lock(&cpufreq_fast_switch_lock); |
1792 | ||
b4dfdbb3 | 1793 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1794 | &cpufreq_transition_notifier_list, nb); |
b7898fda RW |
1795 | if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) |
1796 | cpufreq_fast_switch_count++; | |
1797 | ||
1798 | mutex_unlock(&cpufreq_fast_switch_lock); | |
1da177e4 LT |
1799 | break; |
1800 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1801 | ret = blocking_notifier_chain_unregister( |
1802 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1803 | break; |
1804 | default: | |
1805 | ret = -EINVAL; | |
1806 | } | |
1da177e4 LT |
1807 | |
1808 | return ret; | |
1809 | } | |
1810 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1811 | ||
1812 | ||
1813 | /********************************************************************* | |
1814 | * GOVERNORS * | |
1815 | *********************************************************************/ | |
1816 | ||
b7898fda RW |
1817 | /** |
1818 | * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. | |
1819 | * @policy: cpufreq policy to switch the frequency for. | |
1820 | * @target_freq: New frequency to set (may be approximate). | |
1821 | * | |
1822 | * Carry out a fast frequency switch without sleeping. | |
1823 | * | |
1824 | * The driver's ->fast_switch() callback invoked by this function must be | |
1825 | * suitable for being called from within RCU-sched read-side critical sections | |
1826 | * and it is expected to select the minimum available frequency greater than or | |
1827 | * equal to @target_freq (CPUFREQ_RELATION_L). | |
1828 | * | |
1829 | * This function must not be called if policy->fast_switch_enabled is unset. | |
1830 | * | |
1831 | * Governors calling this function must guarantee that it will never be invoked | |
1832 | * twice in parallel for the same policy and that it will never be called in | |
1833 | * parallel with either ->target() or ->target_index() for the same policy. | |
1834 | * | |
1835 | * If CPUFREQ_ENTRY_INVALID is returned by the driver's ->fast_switch() | |
1836 | * callback to indicate an error condition, the hardware configuration must be | |
1837 | * preserved. | |
1838 | */ | |
1839 | unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, | |
1840 | unsigned int target_freq) | |
1841 | { | |
b9af6948 | 1842 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
b7898fda RW |
1843 | |
1844 | return cpufreq_driver->fast_switch(policy, target_freq); | |
1845 | } | |
1846 | EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); | |
1847 | ||
1c03a2d0 VK |
1848 | /* Must set freqs->new to intermediate frequency */ |
1849 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1850 | struct cpufreq_freqs *freqs, int index) | |
1851 | { | |
1852 | int ret; | |
1853 | ||
1854 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1855 | ||
1856 | /* We don't need to switch to intermediate freq */ | |
1857 | if (!freqs->new) | |
1858 | return 0; | |
1859 | ||
1860 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1861 | __func__, policy->cpu, freqs->old, freqs->new); | |
1862 | ||
1863 | cpufreq_freq_transition_begin(policy, freqs); | |
1864 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1865 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1866 | ||
1867 | if (ret) | |
1868 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1869 | __func__, ret); | |
1870 | ||
1871 | return ret; | |
1872 | } | |
1873 | ||
23727845 | 1874 | static int __target_index(struct cpufreq_policy *policy, int index) |
8d65775d | 1875 | { |
1c03a2d0 VK |
1876 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1877 | unsigned int intermediate_freq = 0; | |
23727845 | 1878 | unsigned int newfreq = policy->freq_table[index].frequency; |
8d65775d VK |
1879 | int retval = -EINVAL; |
1880 | bool notify; | |
1881 | ||
23727845 VK |
1882 | if (newfreq == policy->cur) |
1883 | return 0; | |
1884 | ||
8d65775d | 1885 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); |
8d65775d | 1886 | if (notify) { |
1c03a2d0 VK |
1887 | /* Handle switching to intermediate frequency */ |
1888 | if (cpufreq_driver->get_intermediate) { | |
1889 | retval = __target_intermediate(policy, &freqs, index); | |
1890 | if (retval) | |
1891 | return retval; | |
1892 | ||
1893 | intermediate_freq = freqs.new; | |
1894 | /* Set old freq to intermediate */ | |
1895 | if (intermediate_freq) | |
1896 | freqs.old = freqs.new; | |
1897 | } | |
8d65775d | 1898 | |
23727845 | 1899 | freqs.new = newfreq; |
8d65775d VK |
1900 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1901 | __func__, policy->cpu, freqs.old, freqs.new); | |
1902 | ||
1903 | cpufreq_freq_transition_begin(policy, &freqs); | |
1904 | } | |
1905 | ||
1906 | retval = cpufreq_driver->target_index(policy, index); | |
1907 | if (retval) | |
1908 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1909 | retval); | |
1910 | ||
1c03a2d0 | 1911 | if (notify) { |
8d65775d VK |
1912 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1913 | ||
1c03a2d0 VK |
1914 | /* |
1915 | * Failed after setting to intermediate freq? Driver should have | |
1916 | * reverted back to initial frequency and so should we. Check | |
1917 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1918 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1919 | */ |
1920 | if (unlikely(retval && intermediate_freq)) { | |
1921 | freqs.old = intermediate_freq; | |
1922 | freqs.new = policy->restore_freq; | |
1923 | cpufreq_freq_transition_begin(policy, &freqs); | |
1924 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1925 | } | |
1926 | } | |
1927 | ||
8d65775d VK |
1928 | return retval; |
1929 | } | |
1930 | ||
1da177e4 LT |
1931 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1932 | unsigned int target_freq, | |
1933 | unsigned int relation) | |
1934 | { | |
7249924e | 1935 | unsigned int old_target_freq = target_freq; |
d218ed77 | 1936 | int index; |
c32b6b8e | 1937 | |
a7b422cd KRW |
1938 | if (cpufreq_disabled()) |
1939 | return -ENODEV; | |
1940 | ||
7249924e | 1941 | /* Make sure that target_freq is within supported range */ |
910c6e88 | 1942 | target_freq = clamp_val(target_freq, policy->min, policy->max); |
7249924e VK |
1943 | |
1944 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1945 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1946 | |
9c0ebcf7 VK |
1947 | /* |
1948 | * This might look like a redundant call as we are checking it again | |
1949 | * after finding index. But it is left intentionally for cases where | |
1950 | * exactly same freq is called again and so we can save on few function | |
1951 | * calls. | |
1952 | */ | |
5a1c0228 VK |
1953 | if (target_freq == policy->cur) |
1954 | return 0; | |
1955 | ||
1c03a2d0 VK |
1956 | /* Save last value to restore later on errors */ |
1957 | policy->restore_freq = policy->cur; | |
1958 | ||
1c3d85dd | 1959 | if (cpufreq_driver->target) |
6019d23a | 1960 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 1961 | |
6019d23a RW |
1962 | if (!cpufreq_driver->target_index) |
1963 | return -EINVAL; | |
9c0ebcf7 | 1964 | |
d218ed77 | 1965 | index = cpufreq_frequency_table_target(policy, target_freq, relation); |
6019d23a | 1966 | |
23727845 | 1967 | return __target_index(policy, index); |
1da177e4 LT |
1968 | } |
1969 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1970 | ||
1da177e4 LT |
1971 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1972 | unsigned int target_freq, | |
1973 | unsigned int relation) | |
1974 | { | |
f1829e4a | 1975 | int ret = -EINVAL; |
1da177e4 | 1976 | |
ad7722da | 1977 | down_write(&policy->rwsem); |
1da177e4 LT |
1978 | |
1979 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1980 | ||
ad7722da | 1981 | up_write(&policy->rwsem); |
1da177e4 | 1982 | |
1da177e4 LT |
1983 | return ret; |
1984 | } | |
1985 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1986 | ||
de1df26b RW |
1987 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
1988 | { | |
1989 | return NULL; | |
1990 | } | |
1991 | ||
a92604b4 | 1992 | static int cpufreq_init_governor(struct cpufreq_policy *policy) |
1da177e4 | 1993 | { |
cc993cab | 1994 | int ret; |
6afde10c | 1995 | |
2f0aea93 VK |
1996 | /* Don't start any governor operations if we are entering suspend */ |
1997 | if (cpufreq_suspended) | |
1998 | return 0; | |
cb57720b EZ |
1999 | /* |
2000 | * Governor might not be initiated here if ACPI _PPC changed | |
2001 | * notification happened, so check it. | |
2002 | */ | |
2003 | if (!policy->governor) | |
2004 | return -EINVAL; | |
2f0aea93 | 2005 | |
1c256245 TR |
2006 | if (policy->governor->max_transition_latency && |
2007 | policy->cpuinfo.transition_latency > | |
2008 | policy->governor->max_transition_latency) { | |
de1df26b RW |
2009 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
2010 | ||
2011 | if (gov) { | |
e837f9b5 JP |
2012 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
2013 | policy->governor->name, gov->name); | |
6afde10c | 2014 | policy->governor = gov; |
de1df26b RW |
2015 | } else { |
2016 | return -EINVAL; | |
6afde10c | 2017 | } |
1c256245 | 2018 | } |
1da177e4 | 2019 | |
a92604b4 RW |
2020 | if (!try_module_get(policy->governor->owner)) |
2021 | return -EINVAL; | |
95731ebb | 2022 | |
a92604b4 | 2023 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); |
1da177e4 | 2024 | |
e788892b RW |
2025 | if (policy->governor->init) { |
2026 | ret = policy->governor->init(policy); | |
2027 | if (ret) { | |
36be3418 | 2028 | module_put(policy->governor->owner); |
e788892b RW |
2029 | return ret; |
2030 | } | |
36be3418 | 2031 | } |
1da177e4 | 2032 | |
a92604b4 RW |
2033 | return 0; |
2034 | } | |
2035 | ||
2036 | static void cpufreq_exit_governor(struct cpufreq_policy *policy) | |
2037 | { | |
2038 | if (cpufreq_suspended || !policy->governor) | |
2039 | return; | |
2040 | ||
2041 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2042 | ||
e788892b RW |
2043 | if (policy->governor->exit) |
2044 | policy->governor->exit(policy); | |
a92604b4 | 2045 | |
a92604b4 | 2046 | module_put(policy->governor->owner); |
1da177e4 LT |
2047 | } |
2048 | ||
0a300767 RW |
2049 | static int cpufreq_start_governor(struct cpufreq_policy *policy) |
2050 | { | |
2051 | int ret; | |
2052 | ||
a92604b4 RW |
2053 | if (cpufreq_suspended) |
2054 | return 0; | |
2055 | ||
2056 | if (!policy->governor) | |
2057 | return -EINVAL; | |
2058 | ||
2059 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2060 | ||
3bbf8fe3 RW |
2061 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) |
2062 | cpufreq_update_current_freq(policy); | |
2063 | ||
e788892b RW |
2064 | if (policy->governor->start) { |
2065 | ret = policy->governor->start(policy); | |
2066 | if (ret) | |
2067 | return ret; | |
2068 | } | |
2069 | ||
2070 | if (policy->governor->limits) | |
2071 | policy->governor->limits(policy); | |
d6ff44d6 | 2072 | |
d6ff44d6 | 2073 | return 0; |
0a300767 RW |
2074 | } |
2075 | ||
a92604b4 RW |
2076 | static void cpufreq_stop_governor(struct cpufreq_policy *policy) |
2077 | { | |
2078 | if (cpufreq_suspended || !policy->governor) | |
2079 | return; | |
2080 | ||
2081 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2082 | ||
e788892b RW |
2083 | if (policy->governor->stop) |
2084 | policy->governor->stop(policy); | |
a92604b4 RW |
2085 | } |
2086 | ||
2087 | static void cpufreq_governor_limits(struct cpufreq_policy *policy) | |
2088 | { | |
2089 | if (cpufreq_suspended || !policy->governor) | |
2090 | return; | |
2091 | ||
2092 | pr_debug("%s: for CPU %u\n", __func__, policy->cpu); | |
2093 | ||
e788892b RW |
2094 | if (policy->governor->limits) |
2095 | policy->governor->limits(policy); | |
0a300767 RW |
2096 | } |
2097 | ||
1da177e4 LT |
2098 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2099 | { | |
3bcb09a3 | 2100 | int err; |
1da177e4 LT |
2101 | |
2102 | if (!governor) | |
2103 | return -EINVAL; | |
2104 | ||
a7b422cd KRW |
2105 | if (cpufreq_disabled()) |
2106 | return -ENODEV; | |
2107 | ||
3fc54d37 | 2108 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2109 | |
3bcb09a3 | 2110 | err = -EBUSY; |
42f91fa1 | 2111 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2112 | err = 0; |
2113 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2114 | } |
1da177e4 | 2115 | |
32ee8c3e | 2116 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2117 | return err; |
1da177e4 LT |
2118 | } |
2119 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2120 | ||
1da177e4 LT |
2121 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2122 | { | |
4573237b VK |
2123 | struct cpufreq_policy *policy; |
2124 | unsigned long flags; | |
90e41bac | 2125 | |
1da177e4 LT |
2126 | if (!governor) |
2127 | return; | |
2128 | ||
a7b422cd KRW |
2129 | if (cpufreq_disabled()) |
2130 | return; | |
2131 | ||
4573237b VK |
2132 | /* clear last_governor for all inactive policies */ |
2133 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2134 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2135 | if (!strcmp(policy->last_governor, governor->name)) { |
2136 | policy->governor = NULL; | |
4573237b | 2137 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2138 | } |
90e41bac | 2139 | } |
4573237b | 2140 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2141 | |
3fc54d37 | 2142 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2143 | list_del(&governor->governor_list); |
3fc54d37 | 2144 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2145 | return; |
2146 | } | |
2147 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2148 | ||
2149 | ||
1da177e4 LT |
2150 | /********************************************************************* |
2151 | * POLICY INTERFACE * | |
2152 | *********************************************************************/ | |
2153 | ||
2154 | /** | |
2155 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2156 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2157 | * is written | |
1da177e4 LT |
2158 | * |
2159 | * Reads the current cpufreq policy. | |
2160 | */ | |
2161 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2162 | { | |
2163 | struct cpufreq_policy *cpu_policy; | |
2164 | if (!policy) | |
2165 | return -EINVAL; | |
2166 | ||
2167 | cpu_policy = cpufreq_cpu_get(cpu); | |
2168 | if (!cpu_policy) | |
2169 | return -EINVAL; | |
2170 | ||
d5b73cd8 | 2171 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2172 | |
2173 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2174 | return 0; |
2175 | } | |
2176 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2177 | ||
153d7f3f | 2178 | /* |
037ce839 VK |
2179 | * policy : current policy. |
2180 | * new_policy: policy to be set. | |
153d7f3f | 2181 | */ |
037ce839 | 2182 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2183 | struct cpufreq_policy *new_policy) |
1da177e4 | 2184 | { |
d9a789c7 RW |
2185 | struct cpufreq_governor *old_gov; |
2186 | int ret; | |
1da177e4 | 2187 | |
e837f9b5 JP |
2188 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2189 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2190 | |
d5b73cd8 | 2191 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2192 | |
fba9573b PX |
2193 | /* |
2194 | * This check works well when we store new min/max freq attributes, | |
2195 | * because new_policy is a copy of policy with one field updated. | |
2196 | */ | |
2197 | if (new_policy->min > new_policy->max) | |
d9a789c7 | 2198 | return -EINVAL; |
9c9a43ed | 2199 | |
1da177e4 | 2200 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2201 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2202 | if (ret) |
d9a789c7 | 2203 | return ret; |
1da177e4 | 2204 | |
1da177e4 | 2205 | /* adjust if necessary - all reasons */ |
e041c683 | 2206 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2207 | CPUFREQ_ADJUST, new_policy); |
1da177e4 | 2208 | |
bb176f7d VK |
2209 | /* |
2210 | * verify the cpu speed can be set within this limit, which might be | |
2211 | * different to the first one | |
2212 | */ | |
3a3e9e06 | 2213 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2214 | if (ret) |
d9a789c7 | 2215 | return ret; |
1da177e4 LT |
2216 | |
2217 | /* notification of the new policy */ | |
e041c683 | 2218 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2219 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2220 | |
3a3e9e06 VK |
2221 | policy->min = new_policy->min; |
2222 | policy->max = new_policy->max; | |
1da177e4 | 2223 | |
e3c06236 SM |
2224 | policy->cached_target_freq = UINT_MAX; |
2225 | ||
2d06d8c4 | 2226 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2227 | policy->min, policy->max); |
1da177e4 | 2228 | |
1c3d85dd | 2229 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2230 | policy->policy = new_policy->policy; |
2d06d8c4 | 2231 | pr_debug("setting range\n"); |
d9a789c7 RW |
2232 | return cpufreq_driver->setpolicy(new_policy); |
2233 | } | |
1da177e4 | 2234 | |
0a300767 RW |
2235 | if (new_policy->governor == policy->governor) { |
2236 | pr_debug("cpufreq: governor limits update\n"); | |
a92604b4 | 2237 | cpufreq_governor_limits(policy); |
d6ff44d6 | 2238 | return 0; |
0a300767 | 2239 | } |
7bd353a9 | 2240 | |
d9a789c7 RW |
2241 | pr_debug("governor switch\n"); |
2242 | ||
2243 | /* save old, working values */ | |
2244 | old_gov = policy->governor; | |
2245 | /* end old governor */ | |
2246 | if (old_gov) { | |
45482c70 | 2247 | cpufreq_stop_governor(policy); |
36be3418 | 2248 | cpufreq_exit_governor(policy); |
1da177e4 LT |
2249 | } |
2250 | ||
d9a789c7 RW |
2251 | /* start new governor */ |
2252 | policy->governor = new_policy->governor; | |
a92604b4 | 2253 | ret = cpufreq_init_governor(policy); |
4bc384ae | 2254 | if (!ret) { |
0a300767 RW |
2255 | ret = cpufreq_start_governor(policy); |
2256 | if (!ret) { | |
2257 | pr_debug("cpufreq: governor change\n"); | |
2258 | return 0; | |
2259 | } | |
b7898fda | 2260 | cpufreq_exit_governor(policy); |
d9a789c7 RW |
2261 | } |
2262 | ||
2263 | /* new governor failed, so re-start old one */ | |
2264 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2265 | if (old_gov) { | |
2266 | policy->governor = old_gov; | |
a92604b4 | 2267 | if (cpufreq_init_governor(policy)) |
4bc384ae VK |
2268 | policy->governor = NULL; |
2269 | else | |
0a300767 | 2270 | cpufreq_start_governor(policy); |
d9a789c7 RW |
2271 | } |
2272 | ||
4bc384ae | 2273 | return ret; |
1da177e4 LT |
2274 | } |
2275 | ||
1da177e4 LT |
2276 | /** |
2277 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2278 | * @cpu: CPU which shall be re-evaluated | |
2279 | * | |
25985edc | 2280 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2281 | * at different times. |
2282 | */ | |
30248fef | 2283 | void cpufreq_update_policy(unsigned int cpu) |
1da177e4 | 2284 | { |
3a3e9e06 VK |
2285 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2286 | struct cpufreq_policy new_policy; | |
1da177e4 | 2287 | |
fefa8ff8 | 2288 | if (!policy) |
30248fef | 2289 | return; |
1da177e4 | 2290 | |
ad7722da | 2291 | down_write(&policy->rwsem); |
1da177e4 | 2292 | |
30248fef | 2293 | if (policy_is_inactive(policy)) |
182e36af | 2294 | goto unlock; |
182e36af | 2295 | |
2d06d8c4 | 2296 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2297 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2298 | new_policy.min = policy->user_policy.min; |
2299 | new_policy.max = policy->user_policy.max; | |
1da177e4 | 2300 | |
bb176f7d VK |
2301 | /* |
2302 | * BIOS might change freq behind our back | |
2303 | * -> ask driver for current freq and notify governors about a change | |
2304 | */ | |
2ed99e39 | 2305 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
30248fef | 2306 | if (cpufreq_suspended) |
742c87bf | 2307 | goto unlock; |
30248fef | 2308 | |
999f5729 | 2309 | new_policy.cur = cpufreq_update_current_freq(policy); |
30248fef | 2310 | if (WARN_ON(!new_policy.cur)) |
fefa8ff8 | 2311 | goto unlock; |
0961dd0d TR |
2312 | } |
2313 | ||
30248fef | 2314 | cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2315 | |
fefa8ff8 | 2316 | unlock: |
ad7722da | 2317 | up_write(&policy->rwsem); |
5a01f2e8 | 2318 | |
3a3e9e06 | 2319 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2320 | } |
2321 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2322 | ||
6f19efc0 LM |
2323 | /********************************************************************* |
2324 | * BOOST * | |
2325 | *********************************************************************/ | |
2326 | static int cpufreq_boost_set_sw(int state) | |
2327 | { | |
6f19efc0 LM |
2328 | struct cpufreq_policy *policy; |
2329 | int ret = -EINVAL; | |
2330 | ||
f963735a | 2331 | for_each_active_policy(policy) { |
f8bfc116 VK |
2332 | if (!policy->freq_table) |
2333 | continue; | |
49f18560 | 2334 | |
f8bfc116 VK |
2335 | ret = cpufreq_frequency_table_cpuinfo(policy, |
2336 | policy->freq_table); | |
2337 | if (ret) { | |
2338 | pr_err("%s: Policy frequency update failed\n", | |
2339 | __func__); | |
2340 | break; | |
6f19efc0 | 2341 | } |
f8bfc116 VK |
2342 | |
2343 | down_write(&policy->rwsem); | |
2344 | policy->user_policy.max = policy->max; | |
2345 | cpufreq_governor_limits(policy); | |
2346 | up_write(&policy->rwsem); | |
6f19efc0 LM |
2347 | } |
2348 | ||
2349 | return ret; | |
2350 | } | |
2351 | ||
2352 | int cpufreq_boost_trigger_state(int state) | |
2353 | { | |
2354 | unsigned long flags; | |
2355 | int ret = 0; | |
2356 | ||
2357 | if (cpufreq_driver->boost_enabled == state) | |
2358 | return 0; | |
2359 | ||
2360 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2361 | cpufreq_driver->boost_enabled = state; | |
2362 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2363 | ||
2364 | ret = cpufreq_driver->set_boost(state); | |
2365 | if (ret) { | |
2366 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2367 | cpufreq_driver->boost_enabled = !state; | |
2368 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2369 | ||
e837f9b5 JP |
2370 | pr_err("%s: Cannot %s BOOST\n", |
2371 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2372 | } |
2373 | ||
2374 | return ret; | |
2375 | } | |
2376 | ||
41669da0 | 2377 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2378 | { |
7a6c79f2 | 2379 | return likely(cpufreq_driver) && cpufreq_driver->set_boost; |
6f19efc0 | 2380 | } |
6f19efc0 | 2381 | |
44139ed4 VK |
2382 | static int create_boost_sysfs_file(void) |
2383 | { | |
2384 | int ret; | |
2385 | ||
c82bd444 | 2386 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2387 | if (ret) |
2388 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2389 | __func__); | |
2390 | ||
2391 | return ret; | |
2392 | } | |
2393 | ||
2394 | static void remove_boost_sysfs_file(void) | |
2395 | { | |
2396 | if (cpufreq_boost_supported()) | |
c82bd444 | 2397 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2398 | } |
2399 | ||
2400 | int cpufreq_enable_boost_support(void) | |
2401 | { | |
2402 | if (!cpufreq_driver) | |
2403 | return -EINVAL; | |
2404 | ||
2405 | if (cpufreq_boost_supported()) | |
2406 | return 0; | |
2407 | ||
7a6c79f2 | 2408 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2409 | |
2410 | /* This will get removed on driver unregister */ | |
2411 | return create_boost_sysfs_file(); | |
2412 | } | |
2413 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2414 | ||
6f19efc0 LM |
2415 | int cpufreq_boost_enabled(void) |
2416 | { | |
2417 | return cpufreq_driver->boost_enabled; | |
2418 | } | |
2419 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2420 | ||
1da177e4 LT |
2421 | /********************************************************************* |
2422 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2423 | *********************************************************************/ | |
27622b06 | 2424 | static enum cpuhp_state hp_online; |
1da177e4 | 2425 | |
c4a3fa26 CY |
2426 | static int cpuhp_cpufreq_online(unsigned int cpu) |
2427 | { | |
2428 | cpufreq_online(cpu); | |
2429 | ||
2430 | return 0; | |
2431 | } | |
2432 | ||
2433 | static int cpuhp_cpufreq_offline(unsigned int cpu) | |
2434 | { | |
2435 | cpufreq_offline(cpu); | |
2436 | ||
2437 | return 0; | |
2438 | } | |
2439 | ||
1da177e4 LT |
2440 | /** |
2441 | * cpufreq_register_driver - register a CPU Frequency driver | |
2442 | * @driver_data: A struct cpufreq_driver containing the values# | |
2443 | * submitted by the CPU Frequency driver. | |
2444 | * | |
bb176f7d | 2445 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2446 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2447 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2448 | * |
2449 | */ | |
221dee28 | 2450 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2451 | { |
2452 | unsigned long flags; | |
2453 | int ret; | |
2454 | ||
a7b422cd KRW |
2455 | if (cpufreq_disabled()) |
2456 | return -ENODEV; | |
2457 | ||
1da177e4 | 2458 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2459 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2460 | driver_data->target) || |
2461 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2462 | driver_data->target)) || |
2463 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2464 | return -EINVAL; |
2465 | ||
2d06d8c4 | 2466 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2467 | |
fdd320da | 2468 | /* Protect against concurrent CPU online/offline. */ |
a92551e4 | 2469 | cpus_read_lock(); |
fdd320da | 2470 | |
0d1857a1 | 2471 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2472 | if (cpufreq_driver) { |
0d1857a1 | 2473 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2474 | ret = -EEXIST; |
2475 | goto out; | |
1da177e4 | 2476 | } |
1c3d85dd | 2477 | cpufreq_driver = driver_data; |
0d1857a1 | 2478 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2479 | |
bc68b7df VK |
2480 | if (driver_data->setpolicy) |
2481 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2482 | ||
7a6c79f2 RW |
2483 | if (cpufreq_boost_supported()) { |
2484 | ret = create_boost_sysfs_file(); | |
2485 | if (ret) | |
2486 | goto err_null_driver; | |
2487 | } | |
6f19efc0 | 2488 | |
8a25a2fd | 2489 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2490 | if (ret) |
6f19efc0 | 2491 | goto err_boost_unreg; |
1da177e4 | 2492 | |
ce1bcfe9 VK |
2493 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2494 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2495 | /* if all ->init() calls failed, unregister */ |
6c770036 | 2496 | ret = -ENODEV; |
ce1bcfe9 VK |
2497 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2498 | driver_data->name); | |
2499 | goto err_if_unreg; | |
1da177e4 LT |
2500 | } |
2501 | ||
a92551e4 SAS |
2502 | ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, |
2503 | "cpufreq:online", | |
2504 | cpuhp_cpufreq_online, | |
2505 | cpuhp_cpufreq_offline); | |
27622b06 SAS |
2506 | if (ret < 0) |
2507 | goto err_if_unreg; | |
2508 | hp_online = ret; | |
5372e054 | 2509 | ret = 0; |
27622b06 | 2510 | |
2d06d8c4 | 2511 | pr_debug("driver %s up and running\n", driver_data->name); |
3834abb4 | 2512 | goto out; |
fdd320da | 2513 | |
8a25a2fd KS |
2514 | err_if_unreg: |
2515 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2516 | err_boost_unreg: |
44139ed4 | 2517 | remove_boost_sysfs_file(); |
8f5bc2ab | 2518 | err_null_driver: |
0d1857a1 | 2519 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2520 | cpufreq_driver = NULL; |
0d1857a1 | 2521 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3834abb4 | 2522 | out: |
a92551e4 | 2523 | cpus_read_unlock(); |
3834abb4 | 2524 | return ret; |
1da177e4 LT |
2525 | } |
2526 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2527 | ||
1da177e4 LT |
2528 | /** |
2529 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2530 | * | |
bb176f7d | 2531 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2532 | * the right to do so, i.e. if you have succeeded in initialising before! |
2533 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2534 | * currently not initialised. | |
2535 | */ | |
221dee28 | 2536 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2537 | { |
2538 | unsigned long flags; | |
2539 | ||
1c3d85dd | 2540 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2541 | return -EINVAL; |
1da177e4 | 2542 | |
2d06d8c4 | 2543 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2544 | |
454d3a25 | 2545 | /* Protect against concurrent cpu hotplug */ |
a92551e4 | 2546 | cpus_read_lock(); |
8a25a2fd | 2547 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2548 | remove_boost_sysfs_file(); |
a92551e4 | 2549 | cpuhp_remove_state_nocalls_cpuslocked(hp_online); |
1da177e4 | 2550 | |
0d1857a1 | 2551 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2552 | |
1c3d85dd | 2553 | cpufreq_driver = NULL; |
6eed9404 | 2554 | |
0d1857a1 | 2555 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
a92551e4 | 2556 | cpus_read_unlock(); |
1da177e4 LT |
2557 | |
2558 | return 0; | |
2559 | } | |
2560 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2561 | |
90de2a4a DA |
2562 | /* |
2563 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2564 | * or mutexes when secondary CPUs are halted. | |
2565 | */ | |
2566 | static struct syscore_ops cpufreq_syscore_ops = { | |
2567 | .shutdown = cpufreq_suspend, | |
2568 | }; | |
2569 | ||
c82bd444 VK |
2570 | struct kobject *cpufreq_global_kobject; |
2571 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2572 | ||
5a01f2e8 VP |
2573 | static int __init cpufreq_core_init(void) |
2574 | { | |
a7b422cd KRW |
2575 | if (cpufreq_disabled()) |
2576 | return -ENODEV; | |
2577 | ||
8eec1020 | 2578 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2579 | BUG_ON(!cpufreq_global_kobject); |
2580 | ||
90de2a4a DA |
2581 | register_syscore_ops(&cpufreq_syscore_ops); |
2582 | ||
5a01f2e8 VP |
2583 | return 0; |
2584 | } | |
d82f2692 | 2585 | module_param(off, int, 0444); |
5a01f2e8 | 2586 | core_initcall(cpufreq_core_init); |