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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/cpufreq
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/cpufreq')
-rw-r--r--drivers/cpufreq/Kconfig118
-rw-r--r--drivers/cpufreq/Makefile14
-rw-r--r--drivers/cpufreq/cpufreq.c1428
-rw-r--r--drivers/cpufreq/cpufreq_ondemand.c491
-rw-r--r--drivers/cpufreq/cpufreq_performance.c61
-rw-r--r--drivers/cpufreq/cpufreq_powersave.c59
-rw-r--r--drivers/cpufreq/cpufreq_stats.c334
-rw-r--r--drivers/cpufreq/cpufreq_userspace.c207
-rw-r--r--drivers/cpufreq/freq_table.c225
9 files changed, 2937 insertions, 0 deletions
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
new file mode 100644
index 000000000000..95882bb1950e
--- /dev/null
+++ b/drivers/cpufreq/Kconfig
@@ -0,0 +1,118 @@
1config CPU_FREQ
2 bool "CPU Frequency scaling"
3 help
4 CPU Frequency scaling allows you to change the clock speed of
5 CPUs on the fly. This is a nice method to save power, because
6 the lower the CPU clock speed, the less power the CPU consumes.
7
8 Note that this driver doesn't automatically change the CPU
9 clock speed, you need to either enable a dynamic cpufreq governor
10 (see below) after boot, or use a userspace tool.
11
12 For details, take a look at <file:Documentation/cpu-freq>.
13
14 If in doubt, say N.
15
16if CPU_FREQ
17
18config CPU_FREQ_TABLE
19 def_tristate m
20
21config CPU_FREQ_DEBUG
22 bool "Enable CPUfreq debugging"
23 help
24 Say Y here to enable CPUfreq subsystem (including drivers)
25 debugging. You will need to activate it via the kernel
26 command line by passing
27 cpufreq.debug=<value>
28
29 To get <value>, add
30 1 to activate CPUfreq core debugging,
31 2 to activate CPUfreq drivers debugging, and
32 4 to activate CPUfreq governor debugging
33
34config CPU_FREQ_STAT
35 tristate "CPU frequency translation statistics"
36 select CPU_FREQ_TABLE
37 default y
38 help
39 This driver exports CPU frequency statistics information through sysfs
40 file system
41
42config CPU_FREQ_STAT_DETAILS
43 bool "CPU frequency translation statistics details"
44 depends on CPU_FREQ_STAT
45 help
46 This will show detail CPU frequency translation table in sysfs file
47 system
48
49choice
50 prompt "Default CPUFreq governor"
51 default CPU_FREQ_DEFAULT_GOV_USERSPACE if CPU_FREQ_SA1100 || CPU_FREQ_SA1110
52 default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
53 help
54 This option sets which CPUFreq governor shall be loaded at
55 startup. If in doubt, select 'performance'.
56
57config CPU_FREQ_DEFAULT_GOV_PERFORMANCE
58 bool "performance"
59 select CPU_FREQ_GOV_PERFORMANCE
60 help
61 Use the CPUFreq governor 'performance' as default. This sets
62 the frequency statically to the highest frequency supported by
63 the CPU.
64
65config CPU_FREQ_DEFAULT_GOV_USERSPACE
66 bool "userspace"
67 select CPU_FREQ_GOV_USERSPACE
68 help
69 Use the CPUFreq governor 'userspace' as default. This allows
70 you to set the CPU frequency manually or when an userspace
71 program shall be able to set the CPU dynamically without having
72 to enable the userspace governor manually.
73
74endchoice
75
76config CPU_FREQ_GOV_PERFORMANCE
77 tristate "'performance' governor"
78 help
79 This cpufreq governor sets the frequency statically to the
80 highest available CPU frequency.
81
82 If in doubt, say Y.
83
84config CPU_FREQ_GOV_POWERSAVE
85 tristate "'powersave' governor"
86 help
87 This cpufreq governor sets the frequency statically to the
88 lowest available CPU frequency.
89
90 If in doubt, say Y.
91
92config CPU_FREQ_GOV_USERSPACE
93 tristate "'userspace' governor for userspace frequency scaling"
94 help
95 Enable this cpufreq governor when you either want to set the
96 CPU frequency manually or when an userspace program shall
97 be able to set the CPU dynamically, like on LART
98 <http://www.lart.tudelft.nl/>
99
100 For details, take a look at <file:Documentation/cpu-freq/>.
101
102 If in doubt, say Y.
103
104config CPU_FREQ_GOV_ONDEMAND
105 tristate "'ondemand' cpufreq policy governor"
106 help
107 'ondemand' - This driver adds a dynamic cpufreq policy governor.
108 The governor does a periodic polling and
109 changes frequency based on the CPU utilization.
110 The support for this governor depends on CPU capability to
111 do fast frequency switching (i.e, very low latency frequency
112 transitions).
113
114 For details, take a look at linux/Documentation/cpu-freq.
115
116 If in doubt, say N.
117
118endif # CPU_FREQ
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
new file mode 100644
index 000000000000..67b16e5a41a7
--- /dev/null
+++ b/drivers/cpufreq/Makefile
@@ -0,0 +1,14 @@
1# CPUfreq core
2obj-$(CONFIG_CPU_FREQ) += cpufreq.o
3# CPUfreq stats
4obj-$(CONFIG_CPU_FREQ_STAT) += cpufreq_stats.o
5
6# CPUfreq governors
7obj-$(CONFIG_CPU_FREQ_GOV_PERFORMANCE) += cpufreq_performance.o
8obj-$(CONFIG_CPU_FREQ_GOV_POWERSAVE) += cpufreq_powersave.o
9obj-$(CONFIG_CPU_FREQ_GOV_USERSPACE) += cpufreq_userspace.o
10obj-$(CONFIG_CPU_FREQ_GOV_ONDEMAND) += cpufreq_ondemand.o
11
12# CPUfreq cross-arch helpers
13obj-$(CONFIG_CPU_FREQ_TABLE) += freq_table.o
14
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
new file mode 100644
index 000000000000..b30001f31610
--- /dev/null
+++ b/drivers/cpufreq/cpufreq.c
@@ -0,0 +1,1428 @@
1/*
2 * linux/drivers/cpufreq/cpufreq.c
3 *
4 * Copyright (C) 2001 Russell King
5 * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12
13#include <linux/config.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/notifier.h>
18#include <linux/cpufreq.h>
19#include <linux/delay.h>
20#include <linux/interrupt.h>
21#include <linux/spinlock.h>
22#include <linux/device.h>
23#include <linux/slab.h>
24#include <linux/cpu.h>
25#include <linux/completion.h>
26
27#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "cpufreq-core", msg)
28
29/**
30 * The "cpufreq driver" - the arch- or hardware-dependend low
31 * level driver of CPUFreq support, and its spinlock. This lock
32 * also protects the cpufreq_cpu_data array.
33 */
34static struct cpufreq_driver *cpufreq_driver;
35static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
36static DEFINE_SPINLOCK(cpufreq_driver_lock);
37
38
39/* we keep a copy of all ->add'ed CPU's struct sys_device here;
40 * as it is only accessed in ->add and ->remove, no lock or reference
41 * count is necessary.
42 */
43static struct sys_device *cpu_sys_devices[NR_CPUS];
44
45
46/* internal prototypes */
47static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
48static void handle_update(void *data);
49static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci);
50
51/**
52 * Two notifier lists: the "policy" list is involved in the
53 * validation process for a new CPU frequency policy; the
54 * "transition" list for kernel code that needs to handle
55 * changes to devices when the CPU clock speed changes.
56 * The mutex locks both lists.
57 */
58static struct notifier_block *cpufreq_policy_notifier_list;
59static struct notifier_block *cpufreq_transition_notifier_list;
60static DECLARE_RWSEM (cpufreq_notifier_rwsem);
61
62
63static LIST_HEAD(cpufreq_governor_list);
64static DECLARE_MUTEX (cpufreq_governor_sem);
65
66struct cpufreq_policy * cpufreq_cpu_get(unsigned int cpu)
67{
68 struct cpufreq_policy *data;
69 unsigned long flags;
70
71 if (cpu >= NR_CPUS)
72 goto err_out;
73
74 /* get the cpufreq driver */
75 spin_lock_irqsave(&cpufreq_driver_lock, flags);
76
77 if (!cpufreq_driver)
78 goto err_out_unlock;
79
80 if (!try_module_get(cpufreq_driver->owner))
81 goto err_out_unlock;
82
83
84 /* get the CPU */
85 data = cpufreq_cpu_data[cpu];
86
87 if (!data)
88 goto err_out_put_module;
89
90 if (!kobject_get(&data->kobj))
91 goto err_out_put_module;
92
93
94 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
95
96 return data;
97
98 err_out_put_module:
99 module_put(cpufreq_driver->owner);
100 err_out_unlock:
101 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
102 err_out:
103 return NULL;
104}
105EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
106
107void cpufreq_cpu_put(struct cpufreq_policy *data)
108{
109 kobject_put(&data->kobj);
110 module_put(cpufreq_driver->owner);
111}
112EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
113
114
115/*********************************************************************
116 * UNIFIED DEBUG HELPERS *
117 *********************************************************************/
118#ifdef CONFIG_CPU_FREQ_DEBUG
119
120/* what part(s) of the CPUfreq subsystem are debugged? */
121static unsigned int debug;
122
123/* is the debug output ratelimit'ed using printk_ratelimit? User can
124 * set or modify this value.
125 */
126static unsigned int debug_ratelimit = 1;
127
128/* is the printk_ratelimit'ing enabled? It's enabled after a successful
129 * loading of a cpufreq driver, temporarily disabled when a new policy
130 * is set, and disabled upon cpufreq driver removal
131 */
132static unsigned int disable_ratelimit = 1;
133static DEFINE_SPINLOCK(disable_ratelimit_lock);
134
135static inline void cpufreq_debug_enable_ratelimit(void)
136{
137 unsigned long flags;
138
139 spin_lock_irqsave(&disable_ratelimit_lock, flags);
140 if (disable_ratelimit)
141 disable_ratelimit--;
142 spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
143}
144
145static inline void cpufreq_debug_disable_ratelimit(void)
146{
147 unsigned long flags;
148
149 spin_lock_irqsave(&disable_ratelimit_lock, flags);
150 disable_ratelimit++;
151 spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
152}
153
154void cpufreq_debug_printk(unsigned int type, const char *prefix, const char *fmt, ...)
155{
156 char s[256];
157 va_list args;
158 unsigned int len;
159 unsigned long flags;
160
161 WARN_ON(!prefix);
162 if (type & debug) {
163 spin_lock_irqsave(&disable_ratelimit_lock, flags);
164 if (!disable_ratelimit && debug_ratelimit && !printk_ratelimit()) {
165 spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
166 return;
167 }
168 spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
169
170 len = snprintf(s, 256, KERN_DEBUG "%s: ", prefix);
171
172 va_start(args, fmt);
173 len += vsnprintf(&s[len], (256 - len), fmt, args);
174 va_end(args);
175
176 printk(s);
177
178 WARN_ON(len < 5);
179 }
180}
181EXPORT_SYMBOL(cpufreq_debug_printk);
182
183
184module_param(debug, uint, 0644);
185MODULE_PARM_DESC(debug, "CPUfreq debugging: add 1 to debug core, 2 to debug drivers, and 4 to debug governors.");
186
187module_param(debug_ratelimit, uint, 0644);
188MODULE_PARM_DESC(debug_ratelimit, "CPUfreq debugging: set to 0 to disable ratelimiting.");
189
190#else /* !CONFIG_CPU_FREQ_DEBUG */
191
192static inline void cpufreq_debug_enable_ratelimit(void) { return; }
193static inline void cpufreq_debug_disable_ratelimit(void) { return; }
194
195#endif /* CONFIG_CPU_FREQ_DEBUG */
196
197
198/*********************************************************************
199 * EXTERNALLY AFFECTING FREQUENCY CHANGES *
200 *********************************************************************/
201
202/**
203 * adjust_jiffies - adjust the system "loops_per_jiffy"
204 *
205 * This function alters the system "loops_per_jiffy" for the clock
206 * speed change. Note that loops_per_jiffy cannot be updated on SMP
207 * systems as each CPU might be scaled differently. So, use the arch
208 * per-CPU loops_per_jiffy value wherever possible.
209 */
210#ifndef CONFIG_SMP
211static unsigned long l_p_j_ref;
212static unsigned int l_p_j_ref_freq;
213
214static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
215{
216 if (ci->flags & CPUFREQ_CONST_LOOPS)
217 return;
218
219 if (!l_p_j_ref_freq) {
220 l_p_j_ref = loops_per_jiffy;
221 l_p_j_ref_freq = ci->old;
222 dprintk("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq);
223 }
224 if ((val == CPUFREQ_PRECHANGE && ci->old < ci->new) ||
225 (val == CPUFREQ_POSTCHANGE && ci->old > ci->new) ||
226 (val == CPUFREQ_RESUMECHANGE)) {
227 loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, ci->new);
228 dprintk("scaling loops_per_jiffy to %lu for frequency %u kHz\n", loops_per_jiffy, ci->new);
229 }
230}
231#else
232static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) { return; }
233#endif
234
235
236/**
237 * cpufreq_notify_transition - call notifier chain and adjust_jiffies on frequency transition
238 *
239 * This function calls the transition notifiers and the "adjust_jiffies" function. It is called
240 * twice on all CPU frequency changes that have external effects.
241 */
242void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
243{
244 BUG_ON(irqs_disabled());
245
246 freqs->flags = cpufreq_driver->flags;
247 dprintk("notification %u of frequency transition to %u kHz\n", state, freqs->new);
248
249 down_read(&cpufreq_notifier_rwsem);
250 switch (state) {
251 case CPUFREQ_PRECHANGE:
252 /* detect if the driver reported a value as "old frequency" which
253 * is not equal to what the cpufreq core thinks is "old frequency".
254 */
255 if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
256 if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
257 (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)) &&
258 (likely(cpufreq_cpu_data[freqs->cpu]->cur)) &&
259 (unlikely(freqs->old != cpufreq_cpu_data[freqs->cpu]->cur)))
260 {
261 printk(KERN_WARNING "Warning: CPU frequency is %u, "
262 "cpufreq assumed %u kHz.\n", freqs->old, cpufreq_cpu_data[freqs->cpu]->cur);
263 freqs->old = cpufreq_cpu_data[freqs->cpu]->cur;
264 }
265 }
266 notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_PRECHANGE, freqs);
267 adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
268 break;
269 case CPUFREQ_POSTCHANGE:
270 adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
271 notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_POSTCHANGE, freqs);
272 if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
273 (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)))
274 cpufreq_cpu_data[freqs->cpu]->cur = freqs->new;
275 break;
276 }
277 up_read(&cpufreq_notifier_rwsem);
278}
279EXPORT_SYMBOL_GPL(cpufreq_notify_transition);
280
281
282
283/*********************************************************************
284 * SYSFS INTERFACE *
285 *********************************************************************/
286
287/**
288 * cpufreq_parse_governor - parse a governor string
289 */
290static int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
291 struct cpufreq_governor **governor)
292{
293 if (!cpufreq_driver)
294 return -EINVAL;
295 if (cpufreq_driver->setpolicy) {
296 if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) {
297 *policy = CPUFREQ_POLICY_PERFORMANCE;
298 return 0;
299 } else if (!strnicmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) {
300 *policy = CPUFREQ_POLICY_POWERSAVE;
301 return 0;
302 }
303 return -EINVAL;
304 } else {
305 struct cpufreq_governor *t;
306 down(&cpufreq_governor_sem);
307 if (!cpufreq_driver || !cpufreq_driver->target)
308 goto out;
309 list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
310 if (!strnicmp(str_governor,t->name,CPUFREQ_NAME_LEN)) {
311 *governor = t;
312 up(&cpufreq_governor_sem);
313 return 0;
314 }
315 }
316 out:
317 up(&cpufreq_governor_sem);
318 }
319 return -EINVAL;
320}
321EXPORT_SYMBOL_GPL(cpufreq_parse_governor);
322
323
324/* drivers/base/cpu.c */
325extern struct sysdev_class cpu_sysdev_class;
326
327
328/**
329 * cpufreq_per_cpu_attr_read() / show_##file_name() - print out cpufreq information
330 *
331 * Write out information from cpufreq_driver->policy[cpu]; object must be
332 * "unsigned int".
333 */
334
335#define show_one(file_name, object) \
336static ssize_t show_##file_name \
337(struct cpufreq_policy * policy, char *buf) \
338{ \
339 return sprintf (buf, "%u\n", policy->object); \
340}
341
342show_one(cpuinfo_min_freq, cpuinfo.min_freq);
343show_one(cpuinfo_max_freq, cpuinfo.max_freq);
344show_one(scaling_min_freq, min);
345show_one(scaling_max_freq, max);
346show_one(scaling_cur_freq, cur);
347
348/**
349 * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access
350 */
351#define store_one(file_name, object) \
352static ssize_t store_##file_name \
353(struct cpufreq_policy * policy, const char *buf, size_t count) \
354{ \
355 unsigned int ret = -EINVAL; \
356 struct cpufreq_policy new_policy; \
357 \
358 ret = cpufreq_get_policy(&new_policy, policy->cpu); \
359 if (ret) \
360 return -EINVAL; \
361 \
362 ret = sscanf (buf, "%u", &new_policy.object); \
363 if (ret != 1) \
364 return -EINVAL; \
365 \
366 ret = cpufreq_set_policy(&new_policy); \
367 \
368 return ret ? ret : count; \
369}
370
371store_one(scaling_min_freq,min);
372store_one(scaling_max_freq,max);
373
374/**
375 * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware
376 */
377static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy, char *buf)
378{
379 unsigned int cur_freq = cpufreq_get(policy->cpu);
380 if (!cur_freq)
381 return sprintf(buf, "<unknown>");
382 return sprintf(buf, "%u\n", cur_freq);
383}
384
385
386/**
387 * show_scaling_governor - show the current policy for the specified CPU
388 */
389static ssize_t show_scaling_governor (struct cpufreq_policy * policy, char *buf)
390{
391 if(policy->policy == CPUFREQ_POLICY_POWERSAVE)
392 return sprintf(buf, "powersave\n");
393 else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE)
394 return sprintf(buf, "performance\n");
395 else if (policy->governor)
396 return scnprintf(buf, CPUFREQ_NAME_LEN, "%s\n", policy->governor->name);
397 return -EINVAL;
398}
399
400
401/**
402 * store_scaling_governor - store policy for the specified CPU
403 */
404static ssize_t store_scaling_governor (struct cpufreq_policy * policy,
405 const char *buf, size_t count)
406{
407 unsigned int ret = -EINVAL;
408 char str_governor[16];
409 struct cpufreq_policy new_policy;
410
411 ret = cpufreq_get_policy(&new_policy, policy->cpu);
412 if (ret)
413 return ret;
414
415 ret = sscanf (buf, "%15s", str_governor);
416 if (ret != 1)
417 return -EINVAL;
418
419 if (cpufreq_parse_governor(str_governor, &new_policy.policy, &new_policy.governor))
420 return -EINVAL;
421
422 ret = cpufreq_set_policy(&new_policy);
423
424 return ret ? ret : count;
425}
426
427/**
428 * show_scaling_driver - show the cpufreq driver currently loaded
429 */
430static ssize_t show_scaling_driver (struct cpufreq_policy * policy, char *buf)
431{
432 return scnprintf(buf, CPUFREQ_NAME_LEN, "%s\n", cpufreq_driver->name);
433}
434
435/**
436 * show_scaling_available_governors - show the available CPUfreq governors
437 */
438static ssize_t show_scaling_available_governors (struct cpufreq_policy * policy,
439 char *buf)
440{
441 ssize_t i = 0;
442 struct cpufreq_governor *t;
443
444 if (!cpufreq_driver->target) {
445 i += sprintf(buf, "performance powersave");
446 goto out;
447 }
448
449 list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
450 if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) - (CPUFREQ_NAME_LEN + 2)))
451 goto out;
452 i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name);
453 }
454 out:
455 i += sprintf(&buf[i], "\n");
456 return i;
457}
458/**
459 * show_affected_cpus - show the CPUs affected by each transition
460 */
461static ssize_t show_affected_cpus (struct cpufreq_policy * policy, char *buf)
462{
463 ssize_t i = 0;
464 unsigned int cpu;
465
466 for_each_cpu_mask(cpu, policy->cpus) {
467 if (i)
468 i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " ");
469 i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu);
470 if (i >= (PAGE_SIZE - 5))
471 break;
472 }
473 i += sprintf(&buf[i], "\n");
474 return i;
475}
476
477
478#define define_one_ro(_name) \
479static struct freq_attr _name = \
480__ATTR(_name, 0444, show_##_name, NULL)
481
482#define define_one_ro0400(_name) \
483static struct freq_attr _name = \
484__ATTR(_name, 0400, show_##_name, NULL)
485
486#define define_one_rw(_name) \
487static struct freq_attr _name = \
488__ATTR(_name, 0644, show_##_name, store_##_name)
489
490define_one_ro0400(cpuinfo_cur_freq);
491define_one_ro(cpuinfo_min_freq);
492define_one_ro(cpuinfo_max_freq);
493define_one_ro(scaling_available_governors);
494define_one_ro(scaling_driver);
495define_one_ro(scaling_cur_freq);
496define_one_ro(affected_cpus);
497define_one_rw(scaling_min_freq);
498define_one_rw(scaling_max_freq);
499define_one_rw(scaling_governor);
500
501static struct attribute * default_attrs[] = {
502 &cpuinfo_min_freq.attr,
503 &cpuinfo_max_freq.attr,
504 &scaling_min_freq.attr,
505 &scaling_max_freq.attr,
506 &affected_cpus.attr,
507 &scaling_governor.attr,
508 &scaling_driver.attr,
509 &scaling_available_governors.attr,
510 NULL
511};
512
513#define to_policy(k) container_of(k,struct cpufreq_policy,kobj)
514#define to_attr(a) container_of(a,struct freq_attr,attr)
515
516static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf)
517{
518 struct cpufreq_policy * policy = to_policy(kobj);
519 struct freq_attr * fattr = to_attr(attr);
520 ssize_t ret;
521 policy = cpufreq_cpu_get(policy->cpu);
522 if (!policy)
523 return -EINVAL;
524 ret = fattr->show ? fattr->show(policy,buf) : 0;
525 cpufreq_cpu_put(policy);
526 return ret;
527}
528
529static ssize_t store(struct kobject * kobj, struct attribute * attr,
530 const char * buf, size_t count)
531{
532 struct cpufreq_policy * policy = to_policy(kobj);
533 struct freq_attr * fattr = to_attr(attr);
534 ssize_t ret;
535 policy = cpufreq_cpu_get(policy->cpu);
536 if (!policy)
537 return -EINVAL;
538 ret = fattr->store ? fattr->store(policy,buf,count) : 0;
539 cpufreq_cpu_put(policy);
540 return ret;
541}
542
543static void cpufreq_sysfs_release(struct kobject * kobj)
544{
545 struct cpufreq_policy * policy = to_policy(kobj);
546 dprintk("last reference is dropped\n");
547 complete(&policy->kobj_unregister);
548}
549
550static struct sysfs_ops sysfs_ops = {
551 .show = show,
552 .store = store,
553};
554
555static struct kobj_type ktype_cpufreq = {
556 .sysfs_ops = &sysfs_ops,
557 .default_attrs = default_attrs,
558 .release = cpufreq_sysfs_release,
559};
560
561
562/**
563 * cpufreq_add_dev - add a CPU device
564 *
565 * Adds the cpufreq interface for a CPU device.
566 */
567static int cpufreq_add_dev (struct sys_device * sys_dev)
568{
569 unsigned int cpu = sys_dev->id;
570 int ret = 0;
571 struct cpufreq_policy new_policy;
572 struct cpufreq_policy *policy;
573 struct freq_attr **drv_attr;
574 unsigned long flags;
575 unsigned int j;
576
577 cpufreq_debug_disable_ratelimit();
578 dprintk("adding CPU %u\n", cpu);
579
580#ifdef CONFIG_SMP
581 /* check whether a different CPU already registered this
582 * CPU because it is in the same boat. */
583 policy = cpufreq_cpu_get(cpu);
584 if (unlikely(policy)) {
585 cpu_sys_devices[cpu] = sys_dev;
586 dprintk("CPU already managed, adding link\n");
587 sysfs_create_link(&sys_dev->kobj, &policy->kobj, "cpufreq");
588 cpufreq_debug_enable_ratelimit();
589 return 0;
590 }
591#endif
592
593 if (!try_module_get(cpufreq_driver->owner)) {
594 ret = -EINVAL;
595 goto module_out;
596 }
597
598 policy = kmalloc(sizeof(struct cpufreq_policy), GFP_KERNEL);
599 if (!policy) {
600 ret = -ENOMEM;
601 goto nomem_out;
602 }
603 memset(policy, 0, sizeof(struct cpufreq_policy));
604
605 policy->cpu = cpu;
606 policy->cpus = cpumask_of_cpu(cpu);
607
608 init_MUTEX_LOCKED(&policy->lock);
609 init_completion(&policy->kobj_unregister);
610 INIT_WORK(&policy->update, handle_update, (void *)(long)cpu);
611
612 /* call driver. From then on the cpufreq must be able
613 * to accept all calls to ->verify and ->setpolicy for this CPU
614 */
615 ret = cpufreq_driver->init(policy);
616 if (ret) {
617 dprintk("initialization failed\n");
618 goto err_out;
619 }
620
621 memcpy(&new_policy, policy, sizeof(struct cpufreq_policy));
622
623 /* prepare interface data */
624 policy->kobj.parent = &sys_dev->kobj;
625 policy->kobj.ktype = &ktype_cpufreq;
626 strlcpy(policy->kobj.name, "cpufreq", KOBJ_NAME_LEN);
627
628 ret = kobject_register(&policy->kobj);
629 if (ret)
630 goto err_out;
631
632 /* set up files for this cpu device */
633 drv_attr = cpufreq_driver->attr;
634 while ((drv_attr) && (*drv_attr)) {
635 sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
636 drv_attr++;
637 }
638 if (cpufreq_driver->get)
639 sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr);
640 if (cpufreq_driver->target)
641 sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
642
643 spin_lock_irqsave(&cpufreq_driver_lock, flags);
644 for_each_cpu_mask(j, policy->cpus)
645 cpufreq_cpu_data[j] = policy;
646 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
647 policy->governor = NULL; /* to assure that the starting sequence is
648 * run in cpufreq_set_policy */
649 up(&policy->lock);
650
651 /* set default policy */
652
653 ret = cpufreq_set_policy(&new_policy);
654 if (ret) {
655 dprintk("setting policy failed\n");
656 goto err_out_unregister;
657 }
658
659 module_put(cpufreq_driver->owner);
660 cpu_sys_devices[cpu] = sys_dev;
661 dprintk("initialization complete\n");
662 cpufreq_debug_enable_ratelimit();
663
664 return 0;
665
666
667err_out_unregister:
668 spin_lock_irqsave(&cpufreq_driver_lock, flags);
669 for_each_cpu_mask(j, policy->cpus)
670 cpufreq_cpu_data[j] = NULL;
671 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
672
673 kobject_unregister(&policy->kobj);
674 wait_for_completion(&policy->kobj_unregister);
675
676err_out:
677 kfree(policy);
678
679nomem_out:
680 module_put(cpufreq_driver->owner);
681 module_out:
682 cpufreq_debug_enable_ratelimit();
683 return ret;
684}
685
686
687/**
688 * cpufreq_remove_dev - remove a CPU device
689 *
690 * Removes the cpufreq interface for a CPU device.
691 */
692static int cpufreq_remove_dev (struct sys_device * sys_dev)
693{
694 unsigned int cpu = sys_dev->id;
695 unsigned long flags;
696 struct cpufreq_policy *data;
697#ifdef CONFIG_SMP
698 unsigned int j;
699#endif
700
701 cpufreq_debug_disable_ratelimit();
702 dprintk("unregistering CPU %u\n", cpu);
703
704 spin_lock_irqsave(&cpufreq_driver_lock, flags);
705 data = cpufreq_cpu_data[cpu];
706
707 if (!data) {
708 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
709 cpu_sys_devices[cpu] = NULL;
710 cpufreq_debug_enable_ratelimit();
711 return -EINVAL;
712 }
713 cpufreq_cpu_data[cpu] = NULL;
714
715
716#ifdef CONFIG_SMP
717 /* if this isn't the CPU which is the parent of the kobj, we
718 * only need to unlink, put and exit
719 */
720 if (unlikely(cpu != data->cpu)) {
721 dprintk("removing link\n");
722 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
723 sysfs_remove_link(&sys_dev->kobj, "cpufreq");
724 cpu_sys_devices[cpu] = NULL;
725 cpufreq_cpu_put(data);
726 cpufreq_debug_enable_ratelimit();
727 return 0;
728 }
729#endif
730
731 cpu_sys_devices[cpu] = NULL;
732
733 if (!kobject_get(&data->kobj)) {
734 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
735 cpufreq_debug_enable_ratelimit();
736 return -EFAULT;
737 }
738
739#ifdef CONFIG_SMP
740 /* if we have other CPUs still registered, we need to unlink them,
741 * or else wait_for_completion below will lock up. Clean the
742 * cpufreq_cpu_data[] while holding the lock, and remove the sysfs
743 * links afterwards.
744 */
745 if (unlikely(cpus_weight(data->cpus) > 1)) {
746 for_each_cpu_mask(j, data->cpus) {
747 if (j == cpu)
748 continue;
749 cpufreq_cpu_data[j] = NULL;
750 }
751 }
752
753 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
754
755 if (unlikely(cpus_weight(data->cpus) > 1)) {
756 for_each_cpu_mask(j, data->cpus) {
757 if (j == cpu)
758 continue;
759 dprintk("removing link for cpu %u\n", j);
760 sysfs_remove_link(&cpu_sys_devices[j]->kobj, "cpufreq");
761 cpufreq_cpu_put(data);
762 }
763 }
764#else
765 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
766#endif
767
768 down(&data->lock);
769 if (cpufreq_driver->target)
770 __cpufreq_governor(data, CPUFREQ_GOV_STOP);
771 cpufreq_driver->target = NULL;
772 up(&data->lock);
773
774 kobject_unregister(&data->kobj);
775
776 kobject_put(&data->kobj);
777
778 /* we need to make sure that the underlying kobj is actually
779 * not referenced anymore by anybody before we proceed with
780 * unloading.
781 */
782 dprintk("waiting for dropping of refcount\n");
783 wait_for_completion(&data->kobj_unregister);
784 dprintk("wait complete\n");
785
786 if (cpufreq_driver->exit)
787 cpufreq_driver->exit(data);
788
789 kfree(data);
790
791 cpufreq_debug_enable_ratelimit();
792
793 return 0;
794}
795
796
797static void handle_update(void *data)
798{
799 unsigned int cpu = (unsigned int)(long)data;
800 dprintk("handle_update for cpu %u called\n", cpu);
801 cpufreq_update_policy(cpu);
802}
803
804/**
805 * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're in deep trouble.
806 * @cpu: cpu number
807 * @old_freq: CPU frequency the kernel thinks the CPU runs at
808 * @new_freq: CPU frequency the CPU actually runs at
809 *
810 * We adjust to current frequency first, and need to clean up later. So either call
811 * to cpufreq_update_policy() or schedule handle_update()).
812 */
813static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, unsigned int new_freq)
814{
815 struct cpufreq_freqs freqs;
816
817 printk(KERN_WARNING "Warning: CPU frequency out of sync: cpufreq and timing "
818 "core thinks of %u, is %u kHz.\n", old_freq, new_freq);
819
820 freqs.cpu = cpu;
821 freqs.old = old_freq;
822 freqs.new = new_freq;
823 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
824 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
825}
826
827
828/**
829 * cpufreq_get - get the current CPU frequency (in kHz)
830 * @cpu: CPU number
831 *
832 * Get the CPU current (static) CPU frequency
833 */
834unsigned int cpufreq_get(unsigned int cpu)
835{
836 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
837 unsigned int ret = 0;
838
839 if (!policy)
840 return 0;
841
842 if (!cpufreq_driver->get)
843 goto out;
844
845 down(&policy->lock);
846
847 ret = cpufreq_driver->get(cpu);
848
849 if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS))
850 {
851 /* verify no discrepancy between actual and saved value exists */
852 if (unlikely(ret != policy->cur)) {
853 cpufreq_out_of_sync(cpu, policy->cur, ret);
854 schedule_work(&policy->update);
855 }
856 }
857
858 up(&policy->lock);
859
860 out:
861 cpufreq_cpu_put(policy);
862
863 return (ret);
864}
865EXPORT_SYMBOL(cpufreq_get);
866
867
868/**
869 * cpufreq_resume - restore proper CPU frequency handling after resume
870 *
871 * 1.) resume CPUfreq hardware support (cpufreq_driver->resume())
872 * 2.) if ->target and !CPUFREQ_CONST_LOOPS: verify we're in sync
873 * 3.) schedule call cpufreq_update_policy() ASAP as interrupts are restored.
874 */
875static int cpufreq_resume(struct sys_device * sysdev)
876{
877 int cpu = sysdev->id;
878 unsigned int ret = 0;
879 struct cpufreq_policy *cpu_policy;
880
881 dprintk("resuming cpu %u\n", cpu);
882
883 if (!cpu_online(cpu))
884 return 0;
885
886 /* we may be lax here as interrupts are off. Nonetheless
887 * we need to grab the correct cpu policy, as to check
888 * whether we really run on this CPU.
889 */
890
891 cpu_policy = cpufreq_cpu_get(cpu);
892 if (!cpu_policy)
893 return -EINVAL;
894
895 /* only handle each CPU group once */
896 if (unlikely(cpu_policy->cpu != cpu)) {
897 cpufreq_cpu_put(cpu_policy);
898 return 0;
899 }
900
901 if (cpufreq_driver->resume) {
902 ret = cpufreq_driver->resume(cpu_policy);
903 if (ret) {
904 printk(KERN_ERR "cpufreq: resume failed in ->resume "
905 "step on CPU %u\n", cpu_policy->cpu);
906 cpufreq_cpu_put(cpu_policy);
907 return ret;
908 }
909 }
910
911 if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
912 unsigned int cur_freq = 0;
913
914 if (cpufreq_driver->get)
915 cur_freq = cpufreq_driver->get(cpu_policy->cpu);
916
917 if (!cur_freq || !cpu_policy->cur) {
918 printk(KERN_ERR "cpufreq: resume failed to assert current frequency is what timing core thinks it is.\n");
919 goto out;
920 }
921
922 if (unlikely(cur_freq != cpu_policy->cur)) {
923 struct cpufreq_freqs freqs;
924
925 printk(KERN_WARNING "Warning: CPU frequency is %u, "
926 "cpufreq assumed %u kHz.\n", cur_freq, cpu_policy->cur);
927
928 freqs.cpu = cpu;
929 freqs.old = cpu_policy->cur;
930 freqs.new = cur_freq;
931
932 notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_RESUMECHANGE, &freqs);
933 adjust_jiffies(CPUFREQ_RESUMECHANGE, &freqs);
934
935 cpu_policy->cur = cur_freq;
936 }
937 }
938
939out:
940 schedule_work(&cpu_policy->update);
941 cpufreq_cpu_put(cpu_policy);
942 return ret;
943}
944
945static struct sysdev_driver cpufreq_sysdev_driver = {
946 .add = cpufreq_add_dev,
947 .remove = cpufreq_remove_dev,
948 .resume = cpufreq_resume,
949};
950
951
952/*********************************************************************
953 * NOTIFIER LISTS INTERFACE *
954 *********************************************************************/
955
956/**
957 * cpufreq_register_notifier - register a driver with cpufreq
958 * @nb: notifier function to register
959 * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
960 *
961 * Add a driver to one of two lists: either a list of drivers that
962 * are notified about clock rate changes (once before and once after
963 * the transition), or a list of drivers that are notified about
964 * changes in cpufreq policy.
965 *
966 * This function may sleep, and has the same return conditions as
967 * notifier_chain_register.
968 */
969int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
970{
971 int ret;
972
973 down_write(&cpufreq_notifier_rwsem);
974 switch (list) {
975 case CPUFREQ_TRANSITION_NOTIFIER:
976 ret = notifier_chain_register(&cpufreq_transition_notifier_list, nb);
977 break;
978 case CPUFREQ_POLICY_NOTIFIER:
979 ret = notifier_chain_register(&cpufreq_policy_notifier_list, nb);
980 break;
981 default:
982 ret = -EINVAL;
983 }
984 up_write(&cpufreq_notifier_rwsem);
985
986 return ret;
987}
988EXPORT_SYMBOL(cpufreq_register_notifier);
989
990
991/**
992 * cpufreq_unregister_notifier - unregister a driver with cpufreq
993 * @nb: notifier block to be unregistered
994 * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
995 *
996 * Remove a driver from the CPU frequency notifier list.
997 *
998 * This function may sleep, and has the same return conditions as
999 * notifier_chain_unregister.
1000 */
1001int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
1002{
1003 int ret;
1004
1005 down_write(&cpufreq_notifier_rwsem);
1006 switch (list) {
1007 case CPUFREQ_TRANSITION_NOTIFIER:
1008 ret = notifier_chain_unregister(&cpufreq_transition_notifier_list, nb);
1009 break;
1010 case CPUFREQ_POLICY_NOTIFIER:
1011 ret = notifier_chain_unregister(&cpufreq_policy_notifier_list, nb);
1012 break;
1013 default:
1014 ret = -EINVAL;
1015 }
1016 up_write(&cpufreq_notifier_rwsem);
1017
1018 return ret;
1019}
1020EXPORT_SYMBOL(cpufreq_unregister_notifier);
1021
1022
1023/*********************************************************************
1024 * GOVERNORS *
1025 *********************************************************************/
1026
1027
1028int __cpufreq_driver_target(struct cpufreq_policy *policy,
1029 unsigned int target_freq,
1030 unsigned int relation)
1031{
1032 int retval = -EINVAL;
1033 lock_cpu_hotplug();
1034 dprintk("target for CPU %u: %u kHz, relation %u\n", policy->cpu,
1035 target_freq, relation);
1036 if (cpu_online(policy->cpu) && cpufreq_driver->target)
1037 retval = cpufreq_driver->target(policy, target_freq, relation);
1038 unlock_cpu_hotplug();
1039 return retval;
1040}
1041EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
1042
1043
1044int cpufreq_driver_target(struct cpufreq_policy *policy,
1045 unsigned int target_freq,
1046 unsigned int relation)
1047{
1048 unsigned int ret;
1049
1050 policy = cpufreq_cpu_get(policy->cpu);
1051 if (!policy)
1052 return -EINVAL;
1053
1054 down(&policy->lock);
1055
1056 ret = __cpufreq_driver_target(policy, target_freq, relation);
1057
1058 up(&policy->lock);
1059
1060 cpufreq_cpu_put(policy);
1061
1062 return ret;
1063}
1064EXPORT_SYMBOL_GPL(cpufreq_driver_target);
1065
1066
1067static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
1068{
1069 int ret = -EINVAL;
1070
1071 if (!try_module_get(policy->governor->owner))
1072 return -EINVAL;
1073
1074 dprintk("__cpufreq_governor for CPU %u, event %u\n", policy->cpu, event);
1075 ret = policy->governor->governor(policy, event);
1076
1077 /* we keep one module reference alive for each CPU governed by this CPU */
1078 if ((event != CPUFREQ_GOV_START) || ret)
1079 module_put(policy->governor->owner);
1080 if ((event == CPUFREQ_GOV_STOP) && !ret)
1081 module_put(policy->governor->owner);
1082
1083 return ret;
1084}
1085
1086
1087int cpufreq_governor(unsigned int cpu, unsigned int event)
1088{
1089 int ret = 0;
1090 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
1091
1092 if (!policy)
1093 return -EINVAL;
1094
1095 down(&policy->lock);
1096 ret = __cpufreq_governor(policy, event);
1097 up(&policy->lock);
1098
1099 cpufreq_cpu_put(policy);
1100
1101 return ret;
1102}
1103EXPORT_SYMBOL_GPL(cpufreq_governor);
1104
1105
1106int cpufreq_register_governor(struct cpufreq_governor *governor)
1107{
1108 struct cpufreq_governor *t;
1109
1110 if (!governor)
1111 return -EINVAL;
1112
1113 down(&cpufreq_governor_sem);
1114
1115 list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
1116 if (!strnicmp(governor->name,t->name,CPUFREQ_NAME_LEN)) {
1117 up(&cpufreq_governor_sem);
1118 return -EBUSY;
1119 }
1120 }
1121 list_add(&governor->governor_list, &cpufreq_governor_list);
1122
1123 up(&cpufreq_governor_sem);
1124
1125 return 0;
1126}
1127EXPORT_SYMBOL_GPL(cpufreq_register_governor);
1128
1129
1130void cpufreq_unregister_governor(struct cpufreq_governor *governor)
1131{
1132 if (!governor)
1133 return;
1134
1135 down(&cpufreq_governor_sem);
1136 list_del(&governor->governor_list);
1137 up(&cpufreq_governor_sem);
1138 return;
1139}
1140EXPORT_SYMBOL_GPL(cpufreq_unregister_governor);
1141
1142
1143
1144/*********************************************************************
1145 * POLICY INTERFACE *
1146 *********************************************************************/
1147
1148/**
1149 * cpufreq_get_policy - get the current cpufreq_policy
1150 * @policy: struct cpufreq_policy into which the current cpufreq_policy is written
1151 *
1152 * Reads the current cpufreq policy.
1153 */
1154int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
1155{
1156 struct cpufreq_policy *cpu_policy;
1157 if (!policy)
1158 return -EINVAL;
1159
1160 cpu_policy = cpufreq_cpu_get(cpu);
1161 if (!cpu_policy)
1162 return -EINVAL;
1163
1164 down(&cpu_policy->lock);
1165 memcpy(policy, cpu_policy, sizeof(struct cpufreq_policy));
1166 up(&cpu_policy->lock);
1167
1168 cpufreq_cpu_put(cpu_policy);
1169
1170 return 0;
1171}
1172EXPORT_SYMBOL(cpufreq_get_policy);
1173
1174
1175static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_policy *policy)
1176{
1177 int ret = 0;
1178
1179 cpufreq_debug_disable_ratelimit();
1180 dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
1181 policy->min, policy->max);
1182
1183 memcpy(&policy->cpuinfo,
1184 &data->cpuinfo,
1185 sizeof(struct cpufreq_cpuinfo));
1186
1187 /* verify the cpu speed can be set within this limit */
1188 ret = cpufreq_driver->verify(policy);
1189 if (ret)
1190 goto error_out;
1191
1192 down_read(&cpufreq_notifier_rwsem);
1193
1194 /* adjust if necessary - all reasons */
1195 notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_ADJUST,
1196 policy);
1197
1198 /* adjust if necessary - hardware incompatibility*/
1199 notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_INCOMPATIBLE,
1200 policy);
1201
1202 /* verify the cpu speed can be set within this limit,
1203 which might be different to the first one */
1204 ret = cpufreq_driver->verify(policy);
1205 if (ret) {
1206 up_read(&cpufreq_notifier_rwsem);
1207 goto error_out;
1208 }
1209
1210 /* notification of the new policy */
1211 notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_NOTIFY,
1212 policy);
1213
1214 up_read(&cpufreq_notifier_rwsem);
1215
1216 data->min = policy->min;
1217 data->max = policy->max;
1218
1219 dprintk("new min and max freqs are %u - %u kHz\n", data->min, data->max);
1220
1221 if (cpufreq_driver->setpolicy) {
1222 data->policy = policy->policy;
1223 dprintk("setting range\n");
1224 ret = cpufreq_driver->setpolicy(policy);
1225 } else {
1226 if (policy->governor != data->governor) {
1227 /* save old, working values */
1228 struct cpufreq_governor *old_gov = data->governor;
1229
1230 dprintk("governor switch\n");
1231
1232 /* end old governor */
1233 if (data->governor)
1234 __cpufreq_governor(data, CPUFREQ_GOV_STOP);
1235
1236 /* start new governor */
1237 data->governor = policy->governor;
1238 if (__cpufreq_governor(data, CPUFREQ_GOV_START)) {
1239 /* new governor failed, so re-start old one */
1240 dprintk("starting governor %s failed\n", data->governor->name);
1241 if (old_gov) {
1242 data->governor = old_gov;
1243 __cpufreq_governor(data, CPUFREQ_GOV_START);
1244 }
1245 ret = -EINVAL;
1246 goto error_out;
1247 }
1248 /* might be a policy change, too, so fall through */
1249 }
1250 dprintk("governor: change or update limits\n");
1251 __cpufreq_governor(data, CPUFREQ_GOV_LIMITS);
1252 }
1253
1254 error_out:
1255 cpufreq_debug_enable_ratelimit();
1256 return ret;
1257}
1258
1259/**
1260 * cpufreq_set_policy - set a new CPUFreq policy
1261 * @policy: policy to be set.
1262 *
1263 * Sets a new CPU frequency and voltage scaling policy.
1264 */
1265int cpufreq_set_policy(struct cpufreq_policy *policy)
1266{
1267 int ret = 0;
1268 struct cpufreq_policy *data;
1269
1270 if (!policy)
1271 return -EINVAL;
1272
1273 data = cpufreq_cpu_get(policy->cpu);
1274 if (!data)
1275 return -EINVAL;
1276
1277 /* lock this CPU */
1278 down(&data->lock);
1279
1280 ret = __cpufreq_set_policy(data, policy);
1281 data->user_policy.min = data->min;
1282 data->user_policy.max = data->max;
1283 data->user_policy.policy = data->policy;
1284 data->user_policy.governor = data->governor;
1285
1286 up(&data->lock);
1287 cpufreq_cpu_put(data);
1288
1289 return ret;
1290}
1291EXPORT_SYMBOL(cpufreq_set_policy);
1292
1293
1294/**
1295 * cpufreq_update_policy - re-evaluate an existing cpufreq policy
1296 * @cpu: CPU which shall be re-evaluated
1297 *
1298 * Usefull for policy notifiers which have different necessities
1299 * at different times.
1300 */
1301int cpufreq_update_policy(unsigned int cpu)
1302{
1303 struct cpufreq_policy *data = cpufreq_cpu_get(cpu);
1304 struct cpufreq_policy policy;
1305 int ret = 0;
1306
1307 if (!data)
1308 return -ENODEV;
1309
1310 down(&data->lock);
1311
1312 dprintk("updating policy for CPU %u\n", cpu);
1313 memcpy(&policy,
1314 data,
1315 sizeof(struct cpufreq_policy));
1316 policy.min = data->user_policy.min;
1317 policy.max = data->user_policy.max;
1318 policy.policy = data->user_policy.policy;
1319 policy.governor = data->user_policy.governor;
1320
1321 ret = __cpufreq_set_policy(data, &policy);
1322
1323 up(&data->lock);
1324
1325 cpufreq_cpu_put(data);
1326 return ret;
1327}
1328EXPORT_SYMBOL(cpufreq_update_policy);
1329
1330
1331/*********************************************************************
1332 * REGISTER / UNREGISTER CPUFREQ DRIVER *
1333 *********************************************************************/
1334
1335/**
1336 * cpufreq_register_driver - register a CPU Frequency driver
1337 * @driver_data: A struct cpufreq_driver containing the values#
1338 * submitted by the CPU Frequency driver.
1339 *
1340 * Registers a CPU Frequency driver to this core code. This code
1341 * returns zero on success, -EBUSY when another driver got here first
1342 * (and isn't unregistered in the meantime).
1343 *
1344 */
1345int cpufreq_register_driver(struct cpufreq_driver *driver_data)
1346{
1347 unsigned long flags;
1348 int ret;
1349
1350 if (!driver_data || !driver_data->verify || !driver_data->init ||
1351 ((!driver_data->setpolicy) && (!driver_data->target)))
1352 return -EINVAL;
1353
1354 dprintk("trying to register driver %s\n", driver_data->name);
1355
1356 if (driver_data->setpolicy)
1357 driver_data->flags |= CPUFREQ_CONST_LOOPS;
1358
1359 spin_lock_irqsave(&cpufreq_driver_lock, flags);
1360 if (cpufreq_driver) {
1361 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
1362 return -EBUSY;
1363 }
1364 cpufreq_driver = driver_data;
1365 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
1366
1367 ret = sysdev_driver_register(&cpu_sysdev_class,&cpufreq_sysdev_driver);
1368
1369 if ((!ret) && !(cpufreq_driver->flags & CPUFREQ_STICKY)) {
1370 int i;
1371 ret = -ENODEV;
1372
1373 /* check for at least one working CPU */
1374 for (i=0; i<NR_CPUS; i++)
1375 if (cpufreq_cpu_data[i])
1376 ret = 0;
1377
1378 /* if all ->init() calls failed, unregister */
1379 if (ret) {
1380 dprintk("no CPU initialized for driver %s\n", driver_data->name);
1381 sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver);
1382
1383 spin_lock_irqsave(&cpufreq_driver_lock, flags);
1384 cpufreq_driver = NULL;
1385 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
1386 }
1387 }
1388
1389 if (!ret) {
1390 dprintk("driver %s up and running\n", driver_data->name);
1391 cpufreq_debug_enable_ratelimit();
1392 }
1393
1394 return (ret);
1395}
1396EXPORT_SYMBOL_GPL(cpufreq_register_driver);
1397
1398
1399/**
1400 * cpufreq_unregister_driver - unregister the current CPUFreq driver
1401 *
1402 * Unregister the current CPUFreq driver. Only call this if you have
1403 * the right to do so, i.e. if you have succeeded in initialising before!
1404 * Returns zero if successful, and -EINVAL if the cpufreq_driver is
1405 * currently not initialised.
1406 */
1407int cpufreq_unregister_driver(struct cpufreq_driver *driver)
1408{
1409 unsigned long flags;
1410
1411 cpufreq_debug_disable_ratelimit();
1412
1413 if (!cpufreq_driver || (driver != cpufreq_driver)) {
1414 cpufreq_debug_enable_ratelimit();
1415 return -EINVAL;
1416 }
1417
1418 dprintk("unregistering driver %s\n", driver->name);
1419
1420 sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver);
1421
1422 spin_lock_irqsave(&cpufreq_driver_lock, flags);
1423 cpufreq_driver = NULL;
1424 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
1425
1426 return 0;
1427}
1428EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
new file mode 100644
index 000000000000..8d83a21c6477
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -0,0 +1,491 @@
1/*
2 * drivers/cpufreq/cpufreq_ondemand.c
3 *
4 * Copyright (C) 2001 Russell King
5 * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
6 * Jun Nakajima <jun.nakajima@intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/smp.h>
16#include <linux/init.h>
17#include <linux/interrupt.h>
18#include <linux/ctype.h>
19#include <linux/cpufreq.h>
20#include <linux/sysctl.h>
21#include <linux/types.h>
22#include <linux/fs.h>
23#include <linux/sysfs.h>
24#include <linux/sched.h>
25#include <linux/kmod.h>
26#include <linux/workqueue.h>
27#include <linux/jiffies.h>
28#include <linux/kernel_stat.h>
29#include <linux/percpu.h>
30
31/*
32 * dbs is used in this file as a shortform for demandbased switching
33 * It helps to keep variable names smaller, simpler
34 */
35
36#define DEF_FREQUENCY_UP_THRESHOLD (80)
37#define MIN_FREQUENCY_UP_THRESHOLD (0)
38#define MAX_FREQUENCY_UP_THRESHOLD (100)
39
40#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
41#define MIN_FREQUENCY_DOWN_THRESHOLD (0)
42#define MAX_FREQUENCY_DOWN_THRESHOLD (100)
43
44/*
45 * The polling frequency of this governor depends on the capability of
46 * the processor. Default polling frequency is 1000 times the transition
47 * latency of the processor. The governor will work on any processor with
48 * transition latency <= 10mS, using appropriate sampling
49 * rate.
50 * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL)
51 * this governor will not work.
52 * All times here are in uS.
53 */
54static unsigned int def_sampling_rate;
55#define MIN_SAMPLING_RATE (def_sampling_rate / 2)
56#define MAX_SAMPLING_RATE (500 * def_sampling_rate)
57#define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER (1000)
58#define DEF_SAMPLING_DOWN_FACTOR (10)
59#define TRANSITION_LATENCY_LIMIT (10 * 1000)
60#define sampling_rate_in_HZ(x) (((x * HZ) < (1000 * 1000))?1:((x * HZ) / (1000 * 1000)))
61
62static void do_dbs_timer(void *data);
63
64struct cpu_dbs_info_s {
65 struct cpufreq_policy *cur_policy;
66 unsigned int prev_cpu_idle_up;
67 unsigned int prev_cpu_idle_down;
68 unsigned int enable;
69};
70static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
71
72static unsigned int dbs_enable; /* number of CPUs using this policy */
73
74static DECLARE_MUTEX (dbs_sem);
75static DECLARE_WORK (dbs_work, do_dbs_timer, NULL);
76
77struct dbs_tuners {
78 unsigned int sampling_rate;
79 unsigned int sampling_down_factor;
80 unsigned int up_threshold;
81 unsigned int down_threshold;
82};
83
84static struct dbs_tuners dbs_tuners_ins = {
85 .up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
86 .down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
87 .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
88};
89
90/************************** sysfs interface ************************/
91static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf)
92{
93 return sprintf (buf, "%u\n", MAX_SAMPLING_RATE);
94}
95
96static ssize_t show_sampling_rate_min(struct cpufreq_policy *policy, char *buf)
97{
98 return sprintf (buf, "%u\n", MIN_SAMPLING_RATE);
99}
100
101#define define_one_ro(_name) \
102static struct freq_attr _name = \
103__ATTR(_name, 0444, show_##_name, NULL)
104
105define_one_ro(sampling_rate_max);
106define_one_ro(sampling_rate_min);
107
108/* cpufreq_ondemand Governor Tunables */
109#define show_one(file_name, object) \
110static ssize_t show_##file_name \
111(struct cpufreq_policy *unused, char *buf) \
112{ \
113 return sprintf(buf, "%u\n", dbs_tuners_ins.object); \
114}
115show_one(sampling_rate, sampling_rate);
116show_one(sampling_down_factor, sampling_down_factor);
117show_one(up_threshold, up_threshold);
118show_one(down_threshold, down_threshold);
119
120static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
121 const char *buf, size_t count)
122{
123 unsigned int input;
124 int ret;
125 ret = sscanf (buf, "%u", &input);
126 if (ret != 1 )
127 return -EINVAL;
128
129 down(&dbs_sem);
130 dbs_tuners_ins.sampling_down_factor = input;
131 up(&dbs_sem);
132
133 return count;
134}
135
136static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
137 const char *buf, size_t count)
138{
139 unsigned int input;
140 int ret;
141 ret = sscanf (buf, "%u", &input);
142
143 down(&dbs_sem);
144 if (ret != 1 || input > MAX_SAMPLING_RATE || input < MIN_SAMPLING_RATE) {
145 up(&dbs_sem);
146 return -EINVAL;
147 }
148
149 dbs_tuners_ins.sampling_rate = input;
150 up(&dbs_sem);
151
152 return count;
153}
154
155static ssize_t store_up_threshold(struct cpufreq_policy *unused,
156 const char *buf, size_t count)
157{
158 unsigned int input;
159 int ret;
160 ret = sscanf (buf, "%u", &input);
161
162 down(&dbs_sem);
163 if (ret != 1 || input > MAX_FREQUENCY_UP_THRESHOLD ||
164 input < MIN_FREQUENCY_UP_THRESHOLD ||
165 input <= dbs_tuners_ins.down_threshold) {
166 up(&dbs_sem);
167 return -EINVAL;
168 }
169
170 dbs_tuners_ins.up_threshold = input;
171 up(&dbs_sem);
172
173 return count;
174}
175
176static ssize_t store_down_threshold(struct cpufreq_policy *unused,
177 const char *buf, size_t count)
178{
179 unsigned int input;
180 int ret;
181 ret = sscanf (buf, "%u", &input);
182
183 down(&dbs_sem);
184 if (ret != 1 || input > MAX_FREQUENCY_DOWN_THRESHOLD ||
185 input < MIN_FREQUENCY_DOWN_THRESHOLD ||
186 input >= dbs_tuners_ins.up_threshold) {
187 up(&dbs_sem);
188 return -EINVAL;
189 }
190
191 dbs_tuners_ins.down_threshold = input;
192 up(&dbs_sem);
193
194 return count;
195}
196
197#define define_one_rw(_name) \
198static struct freq_attr _name = \
199__ATTR(_name, 0644, show_##_name, store_##_name)
200
201define_one_rw(sampling_rate);
202define_one_rw(sampling_down_factor);
203define_one_rw(up_threshold);
204define_one_rw(down_threshold);
205
206static struct attribute * dbs_attributes[] = {
207 &sampling_rate_max.attr,
208 &sampling_rate_min.attr,
209 &sampling_rate.attr,
210 &sampling_down_factor.attr,
211 &up_threshold.attr,
212 &down_threshold.attr,
213 NULL
214};
215
216static struct attribute_group dbs_attr_group = {
217 .attrs = dbs_attributes,
218 .name = "ondemand",
219};
220
221/************************** sysfs end ************************/
222
223static void dbs_check_cpu(int cpu)
224{
225 unsigned int idle_ticks, up_idle_ticks, down_idle_ticks;
226 unsigned int total_idle_ticks;
227 unsigned int freq_down_step;
228 unsigned int freq_down_sampling_rate;
229 static int down_skip[NR_CPUS];
230 struct cpu_dbs_info_s *this_dbs_info;
231
232 struct cpufreq_policy *policy;
233 unsigned int j;
234
235 this_dbs_info = &per_cpu(cpu_dbs_info, cpu);
236 if (!this_dbs_info->enable)
237 return;
238
239 policy = this_dbs_info->cur_policy;
240 /*
241 * The default safe range is 20% to 80%
242 * Every sampling_rate, we check
243 * - If current idle time is less than 20%, then we try to
244 * increase frequency
245 * Every sampling_rate*sampling_down_factor, we check
246 * - If current idle time is more than 80%, then we try to
247 * decrease frequency
248 *
249 * Any frequency increase takes it to the maximum frequency.
250 * Frequency reduction happens at minimum steps of
251 * 5% of max_frequency
252 */
253
254 /* Check for frequency increase */
255 total_idle_ticks = kstat_cpu(cpu).cpustat.idle +
256 kstat_cpu(cpu).cpustat.iowait;
257 idle_ticks = total_idle_ticks -
258 this_dbs_info->prev_cpu_idle_up;
259 this_dbs_info->prev_cpu_idle_up = total_idle_ticks;
260
261
262 for_each_cpu_mask(j, policy->cpus) {
263 unsigned int tmp_idle_ticks;
264 struct cpu_dbs_info_s *j_dbs_info;
265
266 if (j == cpu)
267 continue;
268
269 j_dbs_info = &per_cpu(cpu_dbs_info, j);
270 /* Check for frequency increase */
271 total_idle_ticks = kstat_cpu(j).cpustat.idle +
272 kstat_cpu(j).cpustat.iowait;
273 tmp_idle_ticks = total_idle_ticks -
274 j_dbs_info->prev_cpu_idle_up;
275 j_dbs_info->prev_cpu_idle_up = total_idle_ticks;
276
277 if (tmp_idle_ticks < idle_ticks)
278 idle_ticks = tmp_idle_ticks;
279 }
280
281 /* Scale idle ticks by 100 and compare with up and down ticks */
282 idle_ticks *= 100;
283 up_idle_ticks = (100 - dbs_tuners_ins.up_threshold) *
284 sampling_rate_in_HZ(dbs_tuners_ins.sampling_rate);
285
286 if (idle_ticks < up_idle_ticks) {
287 __cpufreq_driver_target(policy, policy->max,
288 CPUFREQ_RELATION_H);
289 down_skip[cpu] = 0;
290 this_dbs_info->prev_cpu_idle_down = total_idle_ticks;
291 return;
292 }
293
294 /* Check for frequency decrease */
295 down_skip[cpu]++;
296 if (down_skip[cpu] < dbs_tuners_ins.sampling_down_factor)
297 return;
298
299 total_idle_ticks = kstat_cpu(cpu).cpustat.idle +
300 kstat_cpu(cpu).cpustat.iowait;
301 idle_ticks = total_idle_ticks -
302 this_dbs_info->prev_cpu_idle_down;
303 this_dbs_info->prev_cpu_idle_down = total_idle_ticks;
304
305 for_each_cpu_mask(j, policy->cpus) {
306 unsigned int tmp_idle_ticks;
307 struct cpu_dbs_info_s *j_dbs_info;
308
309 if (j == cpu)
310 continue;
311
312 j_dbs_info = &per_cpu(cpu_dbs_info, j);
313 /* Check for frequency increase */
314 total_idle_ticks = kstat_cpu(j).cpustat.idle +
315 kstat_cpu(j).cpustat.iowait;
316 tmp_idle_ticks = total_idle_ticks -
317 j_dbs_info->prev_cpu_idle_down;
318 j_dbs_info->prev_cpu_idle_down = total_idle_ticks;
319
320 if (tmp_idle_ticks < idle_ticks)
321 idle_ticks = tmp_idle_ticks;
322 }
323
324 /* Scale idle ticks by 100 and compare with up and down ticks */
325 idle_ticks *= 100;
326 down_skip[cpu] = 0;
327
328 freq_down_sampling_rate = dbs_tuners_ins.sampling_rate *
329 dbs_tuners_ins.sampling_down_factor;
330 down_idle_ticks = (100 - dbs_tuners_ins.down_threshold) *
331 sampling_rate_in_HZ(freq_down_sampling_rate);
332
333 if (idle_ticks > down_idle_ticks ) {
334 freq_down_step = (5 * policy->max) / 100;
335
336 /* max freq cannot be less than 100. But who knows.... */
337 if (unlikely(freq_down_step == 0))
338 freq_down_step = 5;
339
340 __cpufreq_driver_target(policy,
341 policy->cur - freq_down_step,
342 CPUFREQ_RELATION_H);
343 return;
344 }
345}
346
347static void do_dbs_timer(void *data)
348{
349 int i;
350 down(&dbs_sem);
351 for (i = 0; i < NR_CPUS; i++)
352 if (cpu_online(i))
353 dbs_check_cpu(i);
354 schedule_delayed_work(&dbs_work,
355 sampling_rate_in_HZ(dbs_tuners_ins.sampling_rate));
356 up(&dbs_sem);
357}
358
359static inline void dbs_timer_init(void)
360{
361 INIT_WORK(&dbs_work, do_dbs_timer, NULL);
362 schedule_delayed_work(&dbs_work,
363 sampling_rate_in_HZ(dbs_tuners_ins.sampling_rate));
364 return;
365}
366
367static inline void dbs_timer_exit(void)
368{
369 cancel_delayed_work(&dbs_work);
370 return;
371}
372
373static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
374 unsigned int event)
375{
376 unsigned int cpu = policy->cpu;
377 struct cpu_dbs_info_s *this_dbs_info;
378 unsigned int j;
379
380 this_dbs_info = &per_cpu(cpu_dbs_info, cpu);
381
382 switch (event) {
383 case CPUFREQ_GOV_START:
384 if ((!cpu_online(cpu)) ||
385 (!policy->cur))
386 return -EINVAL;
387
388 if (policy->cpuinfo.transition_latency >
389 (TRANSITION_LATENCY_LIMIT * 1000))
390 return -EINVAL;
391 if (this_dbs_info->enable) /* Already enabled */
392 break;
393
394 down(&dbs_sem);
395 for_each_cpu_mask(j, policy->cpus) {
396 struct cpu_dbs_info_s *j_dbs_info;
397 j_dbs_info = &per_cpu(cpu_dbs_info, j);
398 j_dbs_info->cur_policy = policy;
399
400 j_dbs_info->prev_cpu_idle_up =
401 kstat_cpu(j).cpustat.idle +
402 kstat_cpu(j).cpustat.iowait;
403 j_dbs_info->prev_cpu_idle_down =
404 kstat_cpu(j).cpustat.idle +
405 kstat_cpu(j).cpustat.iowait;
406 }
407 this_dbs_info->enable = 1;
408 sysfs_create_group(&policy->kobj, &dbs_attr_group);
409 dbs_enable++;
410 /*
411 * Start the timerschedule work, when this governor
412 * is used for first time
413 */
414 if (dbs_enable == 1) {
415 unsigned int latency;
416 /* policy latency is in nS. Convert it to uS first */
417
418 latency = policy->cpuinfo.transition_latency;
419 if (latency < 1000)
420 latency = 1000;
421
422 def_sampling_rate = (latency / 1000) *
423 DEF_SAMPLING_RATE_LATENCY_MULTIPLIER;
424 dbs_tuners_ins.sampling_rate = def_sampling_rate;
425
426 dbs_timer_init();
427 }
428
429 up(&dbs_sem);
430 break;
431
432 case CPUFREQ_GOV_STOP:
433 down(&dbs_sem);
434 this_dbs_info->enable = 0;
435 sysfs_remove_group(&policy->kobj, &dbs_attr_group);
436 dbs_enable--;
437 /*
438 * Stop the timerschedule work, when this governor
439 * is used for first time
440 */
441 if (dbs_enable == 0)
442 dbs_timer_exit();
443
444 up(&dbs_sem);
445
446 break;
447
448 case CPUFREQ_GOV_LIMITS:
449 down(&dbs_sem);
450 if (policy->max < this_dbs_info->cur_policy->cur)
451 __cpufreq_driver_target(
452 this_dbs_info->cur_policy,
453 policy->max, CPUFREQ_RELATION_H);
454 else if (policy->min > this_dbs_info->cur_policy->cur)
455 __cpufreq_driver_target(
456 this_dbs_info->cur_policy,
457 policy->min, CPUFREQ_RELATION_L);
458 up(&dbs_sem);
459 break;
460 }
461 return 0;
462}
463
464struct cpufreq_governor cpufreq_gov_dbs = {
465 .name = "ondemand",
466 .governor = cpufreq_governor_dbs,
467 .owner = THIS_MODULE,
468};
469EXPORT_SYMBOL(cpufreq_gov_dbs);
470
471static int __init cpufreq_gov_dbs_init(void)
472{
473 return cpufreq_register_governor(&cpufreq_gov_dbs);
474}
475
476static void __exit cpufreq_gov_dbs_exit(void)
477{
478 /* Make sure that the scheduled work is indeed not running */
479 flush_scheduled_work();
480
481 cpufreq_unregister_governor(&cpufreq_gov_dbs);
482}
483
484
485MODULE_AUTHOR ("Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>");
486MODULE_DESCRIPTION ("'cpufreq_ondemand' - A dynamic cpufreq governor for "
487 "Low Latency Frequency Transition capable processors");
488MODULE_LICENSE ("GPL");
489
490module_init(cpufreq_gov_dbs_init);
491module_exit(cpufreq_gov_dbs_exit);
diff --git a/drivers/cpufreq/cpufreq_performance.c b/drivers/cpufreq/cpufreq_performance.c
new file mode 100644
index 000000000000..8d536b40deb8
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_performance.c
@@ -0,0 +1,61 @@
1/*
2 * linux/drivers/cpufreq/cpufreq_performance.c
3 *
4 * Copyright (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/cpufreq.h>
16#include <linux/init.h>
17
18#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_GOVERNOR, "performance", msg)
19
20
21static int cpufreq_governor_performance(struct cpufreq_policy *policy,
22 unsigned int event)
23{
24 switch (event) {
25 case CPUFREQ_GOV_START:
26 case CPUFREQ_GOV_LIMITS:
27 dprintk("setting to %u kHz because of event %u\n", policy->max, event);
28 __cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H);
29 break;
30 default:
31 break;
32 }
33 return 0;
34}
35
36struct cpufreq_governor cpufreq_gov_performance = {
37 .name = "performance",
38 .governor = cpufreq_governor_performance,
39 .owner = THIS_MODULE,
40};
41EXPORT_SYMBOL(cpufreq_gov_performance);
42
43
44static int __init cpufreq_gov_performance_init(void)
45{
46 return cpufreq_register_governor(&cpufreq_gov_performance);
47}
48
49
50static void __exit cpufreq_gov_performance_exit(void)
51{
52 cpufreq_unregister_governor(&cpufreq_gov_performance);
53}
54
55
56MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
57MODULE_DESCRIPTION("CPUfreq policy governor 'performance'");
58MODULE_LICENSE("GPL");
59
60fs_initcall(cpufreq_gov_performance_init);
61module_exit(cpufreq_gov_performance_exit);
diff --git a/drivers/cpufreq/cpufreq_powersave.c b/drivers/cpufreq/cpufreq_powersave.c
new file mode 100644
index 000000000000..c85edda7feb0
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_powersave.c
@@ -0,0 +1,59 @@
1/*
2 * linux/drivers/cpufreq/cpufreq_powersave.c
3 *
4 * Copyright (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/cpufreq.h>
16#include <linux/init.h>
17
18#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_GOVERNOR, "powersave", msg)
19
20static int cpufreq_governor_powersave(struct cpufreq_policy *policy,
21 unsigned int event)
22{
23 switch (event) {
24 case CPUFREQ_GOV_START:
25 case CPUFREQ_GOV_LIMITS:
26 dprintk("setting to %u kHz because of event %u\n", policy->min, event);
27 __cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L);
28 break;
29 default:
30 break;
31 }
32 return 0;
33}
34
35static struct cpufreq_governor cpufreq_gov_powersave = {
36 .name = "powersave",
37 .governor = cpufreq_governor_powersave,
38 .owner = THIS_MODULE,
39};
40
41
42static int __init cpufreq_gov_powersave_init(void)
43{
44 return cpufreq_register_governor(&cpufreq_gov_powersave);
45}
46
47
48static void __exit cpufreq_gov_powersave_exit(void)
49{
50 cpufreq_unregister_governor(&cpufreq_gov_powersave);
51}
52
53
54MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
55MODULE_DESCRIPTION("CPUfreq policy governor 'powersave'");
56MODULE_LICENSE("GPL");
57
58module_init(cpufreq_gov_powersave_init);
59module_exit(cpufreq_gov_powersave_exit);
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
new file mode 100644
index 000000000000..2084593937c6
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -0,0 +1,334 @@
1/*
2 * drivers/cpufreq/cpufreq_stats.c
3 *
4 * Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
5 * (C) 2004 Zou Nan hai <nanhai.zou@intel.com>.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/config.h>
13#include <linux/kernel.h>
14#include <linux/sysdev.h>
15#include <linux/cpu.h>
16#include <linux/sysfs.h>
17#include <linux/cpufreq.h>
18#include <linux/jiffies.h>
19#include <linux/percpu.h>
20#include <linux/kobject.h>
21#include <linux/spinlock.h>
22
23static spinlock_t cpufreq_stats_lock;
24
25#define CPUFREQ_STATDEVICE_ATTR(_name,_mode,_show) \
26static struct freq_attr _attr_##_name = {\
27 .attr = {.name = __stringify(_name), .owner = THIS_MODULE, \
28 .mode = _mode, }, \
29 .show = _show,\
30};
31
32static unsigned long
33delta_time(unsigned long old, unsigned long new)
34{
35 return (old > new) ? (old - new): (new + ~old + 1);
36}
37
38struct cpufreq_stats {
39 unsigned int cpu;
40 unsigned int total_trans;
41 unsigned long long last_time;
42 unsigned int max_state;
43 unsigned int state_num;
44 unsigned int last_index;
45 unsigned long long *time_in_state;
46 unsigned int *freq_table;
47#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
48 unsigned int *trans_table;
49#endif
50};
51
52static struct cpufreq_stats *cpufreq_stats_table[NR_CPUS];
53
54struct cpufreq_stats_attribute {
55 struct attribute attr;
56 ssize_t(*show) (struct cpufreq_stats *, char *);
57};
58
59static int
60cpufreq_stats_update (unsigned int cpu)
61{
62 struct cpufreq_stats *stat;
63 spin_lock(&cpufreq_stats_lock);
64 stat = cpufreq_stats_table[cpu];
65 if (stat->time_in_state)
66 stat->time_in_state[stat->last_index] +=
67 delta_time(stat->last_time, jiffies);
68 stat->last_time = jiffies;
69 spin_unlock(&cpufreq_stats_lock);
70 return 0;
71}
72
73static ssize_t
74show_total_trans(struct cpufreq_policy *policy, char *buf)
75{
76 struct cpufreq_stats *stat = cpufreq_stats_table[policy->cpu];
77 if(!stat)
78 return 0;
79 return sprintf(buf, "%d\n",
80 cpufreq_stats_table[stat->cpu]->total_trans);
81}
82
83static ssize_t
84show_time_in_state(struct cpufreq_policy *policy, char *buf)
85{
86 ssize_t len = 0;
87 int i;
88 struct cpufreq_stats *stat = cpufreq_stats_table[policy->cpu];
89 if(!stat)
90 return 0;
91 cpufreq_stats_update(stat->cpu);
92 for (i = 0; i < stat->state_num; i++) {
93 len += sprintf(buf + len, "%u %llu\n",
94 stat->freq_table[i], stat->time_in_state[i]);
95 }
96 return len;
97}
98
99#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
100static ssize_t
101show_trans_table(struct cpufreq_policy *policy, char *buf)
102{
103 ssize_t len = 0;
104 int i, j;
105
106 struct cpufreq_stats *stat = cpufreq_stats_table[policy->cpu];
107 if(!stat)
108 return 0;
109 cpufreq_stats_update(stat->cpu);
110 for (i = 0; i < stat->state_num; i++) {
111 if (len >= PAGE_SIZE)
112 break;
113 len += snprintf(buf + len, PAGE_SIZE - len, "%9u:\t",
114 stat->freq_table[i]);
115
116 for (j = 0; j < stat->state_num; j++) {
117 if (len >= PAGE_SIZE)
118 break;
119 len += snprintf(buf + len, PAGE_SIZE - len, "%u\t",
120 stat->trans_table[i*stat->max_state+j]);
121 }
122 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
123 }
124 return len;
125}
126CPUFREQ_STATDEVICE_ATTR(trans_table,0444,show_trans_table);
127#endif
128
129CPUFREQ_STATDEVICE_ATTR(total_trans,0444,show_total_trans);
130CPUFREQ_STATDEVICE_ATTR(time_in_state,0444,show_time_in_state);
131
132static struct attribute *default_attrs[] = {
133 &_attr_total_trans.attr,
134 &_attr_time_in_state.attr,
135#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
136 &_attr_trans_table.attr,
137#endif
138 NULL
139};
140static struct attribute_group stats_attr_group = {
141 .attrs = default_attrs,
142 .name = "stats"
143};
144
145static int
146freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
147{
148 int index;
149 for (index = 0; index < stat->max_state; index++)
150 if (stat->freq_table[index] == freq)
151 return index;
152 return -1;
153}
154
155static void
156cpufreq_stats_free_table (unsigned int cpu)
157{
158 struct cpufreq_stats *stat = cpufreq_stats_table[cpu];
159 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
160 if (policy && policy->cpu == cpu)
161 sysfs_remove_group(&policy->kobj, &stats_attr_group);
162 if (stat) {
163 kfree(stat->time_in_state);
164 kfree(stat);
165 }
166 cpufreq_stats_table[cpu] = NULL;
167 if (policy)
168 cpufreq_cpu_put(policy);
169}
170
171static int
172cpufreq_stats_create_table (struct cpufreq_policy *policy,
173 struct cpufreq_frequency_table *table)
174{
175 unsigned int i, j, count = 0, ret = 0;
176 struct cpufreq_stats *stat;
177 struct cpufreq_policy *data;
178 unsigned int alloc_size;
179 unsigned int cpu = policy->cpu;
180 if (cpufreq_stats_table[cpu])
181 return -EBUSY;
182 if ((stat = kmalloc(sizeof(struct cpufreq_stats), GFP_KERNEL)) == NULL)
183 return -ENOMEM;
184 memset(stat, 0, sizeof (struct cpufreq_stats));
185
186 data = cpufreq_cpu_get(cpu);
187 if ((ret = sysfs_create_group(&data->kobj, &stats_attr_group)))
188 goto error_out;
189
190 stat->cpu = cpu;
191 cpufreq_stats_table[cpu] = stat;
192
193 for (i=0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
194 unsigned int freq = table[i].frequency;
195 if (freq == CPUFREQ_ENTRY_INVALID)
196 continue;
197 count++;
198 }
199
200 alloc_size = count * sizeof(int) + count * sizeof(long long);
201
202#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
203 alloc_size += count * count * sizeof(int);
204#endif
205 stat->max_state = count;
206 stat->time_in_state = kmalloc(alloc_size, GFP_KERNEL);
207 if (!stat->time_in_state) {
208 ret = -ENOMEM;
209 goto error_out;
210 }
211 memset(stat->time_in_state, 0, alloc_size);
212 stat->freq_table = (unsigned int *)(stat->time_in_state + count);
213
214#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
215 stat->trans_table = stat->freq_table + count;
216#endif
217 j = 0;
218 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
219 unsigned int freq = table[i].frequency;
220 if (freq == CPUFREQ_ENTRY_INVALID)
221 continue;
222 if (freq_table_get_index(stat, freq) == -1)
223 stat->freq_table[j++] = freq;
224 }
225 stat->state_num = j;
226 spin_lock(&cpufreq_stats_lock);
227 stat->last_time = jiffies;
228 stat->last_index = freq_table_get_index(stat, policy->cur);
229 spin_unlock(&cpufreq_stats_lock);
230 cpufreq_cpu_put(data);
231 return 0;
232error_out:
233 cpufreq_cpu_put(data);
234 kfree(stat);
235 cpufreq_stats_table[cpu] = NULL;
236 return ret;
237}
238
239static int
240cpufreq_stat_notifier_policy (struct notifier_block *nb, unsigned long val,
241 void *data)
242{
243 int ret;
244 struct cpufreq_policy *policy = data;
245 struct cpufreq_frequency_table *table;
246 unsigned int cpu = policy->cpu;
247 if (val != CPUFREQ_NOTIFY)
248 return 0;
249 table = cpufreq_frequency_get_table(cpu);
250 if (!table)
251 return 0;
252 if ((ret = cpufreq_stats_create_table(policy, table)))
253 return ret;
254 return 0;
255}
256
257static int
258cpufreq_stat_notifier_trans (struct notifier_block *nb, unsigned long val,
259 void *data)
260{
261 struct cpufreq_freqs *freq = data;
262 struct cpufreq_stats *stat;
263 int old_index, new_index;
264
265 if (val != CPUFREQ_POSTCHANGE)
266 return 0;
267
268 stat = cpufreq_stats_table[freq->cpu];
269 if (!stat)
270 return 0;
271 old_index = freq_table_get_index(stat, freq->old);
272 new_index = freq_table_get_index(stat, freq->new);
273
274 cpufreq_stats_update(freq->cpu);
275 if (old_index == new_index)
276 return 0;
277
278 spin_lock(&cpufreq_stats_lock);
279 stat->last_index = new_index;
280#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
281 stat->trans_table[old_index * stat->max_state + new_index]++;
282#endif
283 stat->total_trans++;
284 spin_unlock(&cpufreq_stats_lock);
285 return 0;
286}
287
288static struct notifier_block notifier_policy_block = {
289 .notifier_call = cpufreq_stat_notifier_policy
290};
291
292static struct notifier_block notifier_trans_block = {
293 .notifier_call = cpufreq_stat_notifier_trans
294};
295
296static int
297__init cpufreq_stats_init(void)
298{
299 int ret;
300 unsigned int cpu;
301 spin_lock_init(&cpufreq_stats_lock);
302 if ((ret = cpufreq_register_notifier(&notifier_policy_block,
303 CPUFREQ_POLICY_NOTIFIER)))
304 return ret;
305
306 if ((ret = cpufreq_register_notifier(&notifier_trans_block,
307 CPUFREQ_TRANSITION_NOTIFIER))) {
308 cpufreq_unregister_notifier(&notifier_policy_block,
309 CPUFREQ_POLICY_NOTIFIER);
310 return ret;
311 }
312
313 for_each_cpu(cpu)
314 cpufreq_update_policy(cpu);
315 return 0;
316}
317static void
318__exit cpufreq_stats_exit(void)
319{
320 unsigned int cpu;
321 cpufreq_unregister_notifier(&notifier_policy_block,
322 CPUFREQ_POLICY_NOTIFIER);
323 cpufreq_unregister_notifier(&notifier_trans_block,
324 CPUFREQ_TRANSITION_NOTIFIER);
325 for_each_cpu(cpu)
326 cpufreq_stats_free_table(cpu);
327}
328
329MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>");
330MODULE_DESCRIPTION ("'cpufreq_stats' - A driver to export cpufreq stats through sysfs filesystem");
331MODULE_LICENSE ("GPL");
332
333module_init(cpufreq_stats_init);
334module_exit(cpufreq_stats_exit);
diff --git a/drivers/cpufreq/cpufreq_userspace.c b/drivers/cpufreq/cpufreq_userspace.c
new file mode 100644
index 000000000000..d32bf3593cd3
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_userspace.c
@@ -0,0 +1,207 @@
1/*
2 * linux/drivers/cpufreq/cpufreq_userspace.c
3 *
4 * Copyright (C) 2001 Russell King
5 * (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12
13#include <linux/config.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/smp.h>
17#include <linux/init.h>
18#include <linux/spinlock.h>
19#include <linux/interrupt.h>
20#include <linux/cpufreq.h>
21#include <linux/types.h>
22#include <linux/fs.h>
23#include <linux/sysfs.h>
24
25#include <asm/uaccess.h>
26
27
28/**
29 * A few values needed by the userspace governor
30 */
31static unsigned int cpu_max_freq[NR_CPUS];
32static unsigned int cpu_min_freq[NR_CPUS];
33static unsigned int cpu_cur_freq[NR_CPUS]; /* current CPU freq */
34static unsigned int cpu_set_freq[NR_CPUS]; /* CPU freq desired by userspace */
35static unsigned int cpu_is_managed[NR_CPUS];
36static struct cpufreq_policy current_policy[NR_CPUS];
37
38static DECLARE_MUTEX (userspace_sem);
39
40#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_GOVERNOR, "userspace", msg)
41
42/* keep track of frequency transitions */
43static int
44userspace_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
45 void *data)
46{
47 struct cpufreq_freqs *freq = data;
48
49 dprintk("saving cpu_cur_freq of cpu %u to be %u kHz\n", freq->cpu, freq->new);
50 cpu_cur_freq[freq->cpu] = freq->new;
51
52 return 0;
53}
54
55static struct notifier_block userspace_cpufreq_notifier_block = {
56 .notifier_call = userspace_cpufreq_notifier
57};
58
59
60/**
61 * cpufreq_set - set the CPU frequency
62 * @freq: target frequency in kHz
63 * @cpu: CPU for which the frequency is to be set
64 *
65 * Sets the CPU frequency to freq.
66 */
67static int cpufreq_set(unsigned int freq, unsigned int cpu)
68{
69 int ret = -EINVAL;
70
71 dprintk("cpufreq_set for cpu %u, freq %u kHz\n", cpu, freq);
72
73 down(&userspace_sem);
74 if (!cpu_is_managed[cpu])
75 goto err;
76
77 cpu_set_freq[cpu] = freq;
78
79 if (freq < cpu_min_freq[cpu])
80 freq = cpu_min_freq[cpu];
81 if (freq > cpu_max_freq[cpu])
82 freq = cpu_max_freq[cpu];
83
84 /*
85 * We're safe from concurrent calls to ->target() here
86 * as we hold the userspace_sem lock. If we were calling
87 * cpufreq_driver_target, a deadlock situation might occur:
88 * A: cpufreq_set (lock userspace_sem) -> cpufreq_driver_target(lock policy->lock)
89 * B: cpufreq_set_policy(lock policy->lock) -> __cpufreq_governor -> cpufreq_governor_userspace (lock userspace_sem)
90 */
91 ret = __cpufreq_driver_target(&current_policy[cpu], freq,
92 CPUFREQ_RELATION_L);
93
94 err:
95 up(&userspace_sem);
96 return ret;
97}
98
99
100/************************** sysfs interface ************************/
101static ssize_t show_speed (struct cpufreq_policy *policy, char *buf)
102{
103 return sprintf (buf, "%u\n", cpu_cur_freq[policy->cpu]);
104}
105
106static ssize_t
107store_speed (struct cpufreq_policy *policy, const char *buf, size_t count)
108{
109 unsigned int freq = 0;
110 unsigned int ret;
111
112 ret = sscanf (buf, "%u", &freq);
113 if (ret != 1)
114 return -EINVAL;
115
116 cpufreq_set(freq, policy->cpu);
117
118 return count;
119}
120
121static struct freq_attr freq_attr_scaling_setspeed =
122{
123 .attr = { .name = "scaling_setspeed", .mode = 0644, .owner = THIS_MODULE },
124 .show = show_speed,
125 .store = store_speed,
126};
127
128static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
129 unsigned int event)
130{
131 unsigned int cpu = policy->cpu;
132 switch (event) {
133 case CPUFREQ_GOV_START:
134 if (!cpu_online(cpu))
135 return -EINVAL;
136 BUG_ON(!policy->cur);
137 down(&userspace_sem);
138 cpu_is_managed[cpu] = 1;
139 cpu_min_freq[cpu] = policy->min;
140 cpu_max_freq[cpu] = policy->max;
141 cpu_cur_freq[cpu] = policy->cur;
142 cpu_set_freq[cpu] = policy->cur;
143 sysfs_create_file (&policy->kobj, &freq_attr_scaling_setspeed.attr);
144 memcpy (&current_policy[cpu], policy, sizeof(struct cpufreq_policy));
145 dprintk("managing cpu %u started (%u - %u kHz, currently %u kHz)\n", cpu, cpu_min_freq[cpu], cpu_max_freq[cpu], cpu_cur_freq[cpu]);
146 up(&userspace_sem);
147 break;
148 case CPUFREQ_GOV_STOP:
149 down(&userspace_sem);
150 cpu_is_managed[cpu] = 0;
151 cpu_min_freq[cpu] = 0;
152 cpu_max_freq[cpu] = 0;
153 cpu_set_freq[cpu] = 0;
154 sysfs_remove_file (&policy->kobj, &freq_attr_scaling_setspeed.attr);
155 dprintk("managing cpu %u stopped\n", cpu);
156 up(&userspace_sem);
157 break;
158 case CPUFREQ_GOV_LIMITS:
159 down(&userspace_sem);
160 cpu_min_freq[cpu] = policy->min;
161 cpu_max_freq[cpu] = policy->max;
162 dprintk("limit event for cpu %u: %u - %u kHz, currently %u kHz, last set to %u kHz\n", cpu, cpu_min_freq[cpu], cpu_max_freq[cpu], cpu_cur_freq[cpu], cpu_set_freq[cpu]);
163 if (policy->max < cpu_set_freq[cpu]) {
164 __cpufreq_driver_target(&current_policy[cpu], policy->max,
165 CPUFREQ_RELATION_H);
166 } else if (policy->min > cpu_set_freq[cpu]) {
167 __cpufreq_driver_target(&current_policy[cpu], policy->min,
168 CPUFREQ_RELATION_L);
169 } else {
170 __cpufreq_driver_target(&current_policy[cpu], cpu_set_freq[cpu],
171 CPUFREQ_RELATION_L);
172 }
173 memcpy (&current_policy[cpu], policy, sizeof(struct cpufreq_policy));
174 up(&userspace_sem);
175 break;
176 }
177 return 0;
178}
179
180
181struct cpufreq_governor cpufreq_gov_userspace = {
182 .name = "userspace",
183 .governor = cpufreq_governor_userspace,
184 .owner = THIS_MODULE,
185};
186EXPORT_SYMBOL(cpufreq_gov_userspace);
187
188static int __init cpufreq_gov_userspace_init(void)
189{
190 cpufreq_register_notifier(&userspace_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
191 return cpufreq_register_governor(&cpufreq_gov_userspace);
192}
193
194
195static void __exit cpufreq_gov_userspace_exit(void)
196{
197 cpufreq_unregister_governor(&cpufreq_gov_userspace);
198 cpufreq_unregister_notifier(&userspace_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
199}
200
201
202MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>, Russell King <rmk@arm.linux.org.uk>");
203MODULE_DESCRIPTION ("CPUfreq policy governor 'userspace'");
204MODULE_LICENSE ("GPL");
205
206fs_initcall(cpufreq_gov_userspace_init);
207module_exit(cpufreq_gov_userspace_exit);
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
new file mode 100644
index 000000000000..ba460bdea60f
--- /dev/null
+++ b/drivers/cpufreq/freq_table.c
@@ -0,0 +1,225 @@
1/*
2 * linux/drivers/cpufreq/freq_table.c
3 *
4 * Copyright (C) 2002 - 2003 Dominik Brodowski
5 */
6
7#include <linux/kernel.h>
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/cpufreq.h>
11
12#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "freq-table", msg)
13
14/*********************************************************************
15 * FREQUENCY TABLE HELPERS *
16 *********************************************************************/
17
18int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
19 struct cpufreq_frequency_table *table)
20{
21 unsigned int min_freq = ~0;
22 unsigned int max_freq = 0;
23 unsigned int i = 0;
24
25 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
26 unsigned int freq = table[i].frequency;
27 if (freq == CPUFREQ_ENTRY_INVALID) {
28 dprintk("table entry %u is invalid, skipping\n", i);
29
30 continue;
31 }
32 dprintk("table entry %u: %u kHz, %u index\n", i, freq, table[i].index);
33 if (freq < min_freq)
34 min_freq = freq;
35 if (freq > max_freq)
36 max_freq = freq;
37 }
38
39 policy->min = policy->cpuinfo.min_freq = min_freq;
40 policy->max = policy->cpuinfo.max_freq = max_freq;
41
42 if (policy->min == ~0)
43 return -EINVAL;
44 else
45 return 0;
46}
47EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
48
49
50int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
51 struct cpufreq_frequency_table *table)
52{
53 unsigned int next_larger = ~0;
54 unsigned int i = 0;
55 unsigned int count = 0;
56
57 dprintk("request for verification of policy (%u - %u kHz) for cpu %u\n", policy->min, policy->max, policy->cpu);
58
59 if (!cpu_online(policy->cpu))
60 return -EINVAL;
61
62 cpufreq_verify_within_limits(policy,
63 policy->cpuinfo.min_freq,
64 policy->cpuinfo.max_freq);
65
66 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
67 unsigned int freq = table[i].frequency;
68 if (freq == CPUFREQ_ENTRY_INVALID)
69 continue;
70 if ((freq >= policy->min) && (freq <= policy->max))
71 count++;
72 else if ((next_larger > freq) && (freq > policy->max))
73 next_larger = freq;
74 }
75
76 if (!count)
77 policy->max = next_larger;
78
79 cpufreq_verify_within_limits(policy,
80 policy->cpuinfo.min_freq,
81 policy->cpuinfo.max_freq);
82
83 dprintk("verification lead to (%u - %u kHz) for cpu %u\n", policy->min, policy->max, policy->cpu);
84
85 return 0;
86}
87EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
88
89
90int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
91 struct cpufreq_frequency_table *table,
92 unsigned int target_freq,
93 unsigned int relation,
94 unsigned int *index)
95{
96 struct cpufreq_frequency_table optimal = { .index = ~0, };
97 struct cpufreq_frequency_table suboptimal = { .index = ~0, };
98 unsigned int i;
99
100 dprintk("request for target %u kHz (relation: %u) for cpu %u\n", target_freq, relation, policy->cpu);
101
102 switch (relation) {
103 case CPUFREQ_RELATION_H:
104 optimal.frequency = 0;
105 suboptimal.frequency = ~0;
106 break;
107 case CPUFREQ_RELATION_L:
108 optimal.frequency = ~0;
109 suboptimal.frequency = 0;
110 break;
111 }
112
113 if (!cpu_online(policy->cpu))
114 return -EINVAL;
115
116 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
117 unsigned int freq = table[i].frequency;
118 if (freq == CPUFREQ_ENTRY_INVALID)
119 continue;
120 if ((freq < policy->min) || (freq > policy->max))
121 continue;
122 switch(relation) {
123 case CPUFREQ_RELATION_H:
124 if (freq <= target_freq) {
125 if (freq >= optimal.frequency) {
126 optimal.frequency = freq;
127 optimal.index = i;
128 }
129 } else {
130 if (freq <= suboptimal.frequency) {
131 suboptimal.frequency = freq;
132 suboptimal.index = i;
133 }
134 }
135 break;
136 case CPUFREQ_RELATION_L:
137 if (freq >= target_freq) {
138 if (freq <= optimal.frequency) {
139 optimal.frequency = freq;
140 optimal.index = i;
141 }
142 } else {
143 if (freq >= suboptimal.frequency) {
144 suboptimal.frequency = freq;
145 suboptimal.index = i;
146 }
147 }
148 break;
149 }
150 }
151 if (optimal.index > i) {
152 if (suboptimal.index > i)
153 return -EINVAL;
154 *index = suboptimal.index;
155 } else
156 *index = optimal.index;
157
158 dprintk("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
159 table[*index].index);
160
161 return 0;
162}
163EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
164
165static struct cpufreq_frequency_table *show_table[NR_CPUS];
166/**
167 * show_scaling_governor - show the current policy for the specified CPU
168 */
169static ssize_t show_available_freqs (struct cpufreq_policy *policy, char *buf)
170{
171 unsigned int i = 0;
172 unsigned int cpu = policy->cpu;
173 ssize_t count = 0;
174 struct cpufreq_frequency_table *table;
175
176 if (!show_table[cpu])
177 return -ENODEV;
178
179 table = show_table[cpu];
180
181 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
182 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
183 continue;
184 count += sprintf(&buf[count], "%d ", table[i].frequency);
185 }
186 count += sprintf(&buf[count], "\n");
187
188 return count;
189
190}
191
192struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
193 .attr = { .name = "scaling_available_frequencies", .mode = 0444, .owner=THIS_MODULE },
194 .show = show_available_freqs,
195};
196EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
197
198/*
199 * if you use these, you must assure that the frequency table is valid
200 * all the time between get_attr and put_attr!
201 */
202void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
203 unsigned int cpu)
204{
205 dprintk("setting show_table for cpu %u to %p\n", cpu, table);
206 show_table[cpu] = table;
207}
208EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
209
210void cpufreq_frequency_table_put_attr(unsigned int cpu)
211{
212 dprintk("clearing show_table for cpu %u\n", cpu);
213 show_table[cpu] = NULL;
214}
215EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
216
217struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
218{
219 return show_table[cpu];
220}
221EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
222
223MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
224MODULE_DESCRIPTION ("CPUfreq frequency table helpers");
225MODULE_LICENSE ("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2026-05-11 11:45:21 -0400