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path: root/drivers/cpufreq/cpufreq.c
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Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
-rw-r--r--drivers/cpufreq/cpufreq.c110
1 files changed, 56 insertions, 54 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7a511479ae29..9582de1c9cad 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -35,8 +35,8 @@
35 * level driver of CPUFreq support, and its spinlock. This lock 35 * level driver of CPUFreq support, and its spinlock. This lock
36 * also protects the cpufreq_cpu_data array. 36 * also protects the cpufreq_cpu_data array.
37 */ 37 */
38static struct cpufreq_driver *cpufreq_driver; 38static struct cpufreq_driver *cpufreq_driver;
39static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS]; 39static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
40static DEFINE_SPINLOCK(cpufreq_driver_lock); 40static DEFINE_SPINLOCK(cpufreq_driver_lock);
41 41
42/* internal prototypes */ 42/* internal prototypes */
@@ -50,15 +50,15 @@ static void handle_update(void *data);
50 * changes to devices when the CPU clock speed changes. 50 * changes to devices when the CPU clock speed changes.
51 * The mutex locks both lists. 51 * The mutex locks both lists.
52 */ 52 */
53static struct notifier_block *cpufreq_policy_notifier_list; 53static struct notifier_block *cpufreq_policy_notifier_list;
54static struct notifier_block *cpufreq_transition_notifier_list; 54static struct notifier_block *cpufreq_transition_notifier_list;
55static DECLARE_RWSEM (cpufreq_notifier_rwsem); 55static DECLARE_RWSEM (cpufreq_notifier_rwsem);
56 56
57 57
58static LIST_HEAD(cpufreq_governor_list); 58static LIST_HEAD(cpufreq_governor_list);
59static DEFINE_MUTEX (cpufreq_governor_mutex); 59static DEFINE_MUTEX (cpufreq_governor_mutex);
60 60
61struct cpufreq_policy * cpufreq_cpu_get(unsigned int cpu) 61struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
62{ 62{
63 struct cpufreq_policy *data; 63 struct cpufreq_policy *data;
64 unsigned long flags; 64 unsigned long flags;
@@ -85,20 +85,19 @@ struct cpufreq_policy * cpufreq_cpu_get(unsigned int cpu)
85 if (!kobject_get(&data->kobj)) 85 if (!kobject_get(&data->kobj))
86 goto err_out_put_module; 86 goto err_out_put_module;
87 87
88
89 spin_unlock_irqrestore(&cpufreq_driver_lock, flags); 88 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
90
91 return data; 89 return data;
92 90
93 err_out_put_module: 91err_out_put_module:
94 module_put(cpufreq_driver->owner); 92 module_put(cpufreq_driver->owner);
95 err_out_unlock: 93err_out_unlock:
96 spin_unlock_irqrestore(&cpufreq_driver_lock, flags); 94 spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
97 err_out: 95err_out:
98 return NULL; 96 return NULL;
99} 97}
100EXPORT_SYMBOL_GPL(cpufreq_cpu_get); 98EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
101 99
100
102void cpufreq_cpu_put(struct cpufreq_policy *data) 101void cpufreq_cpu_put(struct cpufreq_policy *data)
103{ 102{
104 kobject_put(&data->kobj); 103 kobject_put(&data->kobj);
@@ -229,44 +228,53 @@ static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) {
229 228
230 229
231/** 230/**
232 * cpufreq_notify_transition - call notifier chain and adjust_jiffies on frequency transition 231 * cpufreq_notify_transition - call notifier chain and adjust_jiffies
232 * on frequency transition.
233 * 233 *
234 * This function calls the transition notifiers and the "adjust_jiffies" function. It is called 234 * This function calls the transition notifiers and the "adjust_jiffies"
235 * twice on all CPU frequency changes that have external effects. 235 * function. It is called twice on all CPU frequency changes that have
236 * external effects.
236 */ 237 */
237void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state) 238void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
238{ 239{
240 struct cpufreq_policy *policy;
241
239 BUG_ON(irqs_disabled()); 242 BUG_ON(irqs_disabled());
240 243
241 freqs->flags = cpufreq_driver->flags; 244 freqs->flags = cpufreq_driver->flags;
242 dprintk("notification %u of frequency transition to %u kHz\n", state, freqs->new); 245 dprintk("notification %u of frequency transition to %u kHz\n",
246 state, freqs->new);
243 247
244 down_read(&cpufreq_notifier_rwsem); 248 down_read(&cpufreq_notifier_rwsem);
249
250 policy = cpufreq_cpu_data[freqs->cpu];
245 switch (state) { 251 switch (state) {
252
246 case CPUFREQ_PRECHANGE: 253 case CPUFREQ_PRECHANGE:
247 /* detect if the driver reported a value as "old frequency" which 254 /* detect if the driver reported a value as "old frequency"
248 * is not equal to what the cpufreq core thinks is "old frequency". 255 * which is not equal to what the cpufreq core thinks is
256 * "old frequency".
249 */ 257 */
250 if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { 258 if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
251 if ((likely(cpufreq_cpu_data[freqs->cpu])) && 259 if ((policy) && (policy->cpu == freqs->cpu) &&
252 (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)) && 260 (policy->cur) && (policy->cur != freqs->old)) {
253 (likely(cpufreq_cpu_data[freqs->cpu]->cur)) && 261 dprintk(KERN_WARNING "Warning: CPU frequency is"
254 (unlikely(freqs->old != cpufreq_cpu_data[freqs->cpu]->cur))) 262 " %u, cpufreq assumed %u kHz.\n",
255 { 263 freqs->old, policy->cur);
256 dprintk(KERN_WARNING "Warning: CPU frequency is %u, " 264 freqs->old = policy->cur;
257 "cpufreq assumed %u kHz.\n", freqs->old, cpufreq_cpu_data[freqs->cpu]->cur);
258 freqs->old = cpufreq_cpu_data[freqs->cpu]->cur;
259 } 265 }
260 } 266 }
261 notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_PRECHANGE, freqs); 267 notifier_call_chain(&cpufreq_transition_notifier_list,
268 CPUFREQ_PRECHANGE, freqs);
262 adjust_jiffies(CPUFREQ_PRECHANGE, freqs); 269 adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
263 break; 270 break;
271
264 case CPUFREQ_POSTCHANGE: 272 case CPUFREQ_POSTCHANGE:
265 adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); 273 adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
266 notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_POSTCHANGE, freqs); 274 notifier_call_chain(&cpufreq_transition_notifier_list,
267 if ((likely(cpufreq_cpu_data[freqs->cpu])) && 275 CPUFREQ_POSTCHANGE, freqs);
268 (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu))) 276 if (likely(policy) && likely(policy->cpu == freqs->cpu))
269 cpufreq_cpu_data[freqs->cpu]->cur = freqs->new; 277 policy->cur = freqs->new;
270 break; 278 break;
271 } 279 }
272 up_read(&cpufreq_notifier_rwsem); 280 up_read(&cpufreq_notifier_rwsem);
@@ -308,7 +316,7 @@ static int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
308 return 0; 316 return 0;
309 } 317 }
310 } 318 }
311 out: 319out:
312 mutex_unlock(&cpufreq_governor_mutex); 320 mutex_unlock(&cpufreq_governor_mutex);
313 } 321 }
314 return -EINVAL; 322 return -EINVAL;
@@ -415,7 +423,6 @@ static ssize_t store_scaling_governor (struct cpufreq_policy * policy,
415 return -EINVAL; 423 return -EINVAL;
416 424
417 ret = cpufreq_set_policy(&new_policy); 425 ret = cpufreq_set_policy(&new_policy);
418
419 return ret ? ret : count; 426 return ret ? ret : count;
420} 427}
421 428
@@ -446,7 +453,7 @@ static ssize_t show_scaling_available_governors (struct cpufreq_policy * policy,
446 goto out; 453 goto out;
447 i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name); 454 i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name);
448 } 455 }
449 out: 456out:
450 i += sprintf(&buf[i], "\n"); 457 i += sprintf(&buf[i], "\n");
451 return i; 458 return i;
452} 459}
@@ -789,7 +796,6 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
789 kfree(data); 796 kfree(data);
790 797
791 cpufreq_debug_enable_ratelimit(); 798 cpufreq_debug_enable_ratelimit();
792
793 return 0; 799 return 0;
794} 800}
795 801
@@ -870,8 +876,7 @@ unsigned int cpufreq_get(unsigned int cpu)
870 876
871 ret = cpufreq_driver->get(cpu); 877 ret = cpufreq_driver->get(cpu);
872 878
873 if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) 879 if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
874 {
875 /* verify no discrepancy between actual and saved value exists */ 880 /* verify no discrepancy between actual and saved value exists */
876 if (unlikely(ret != policy->cur)) { 881 if (unlikely(ret != policy->cur)) {
877 cpufreq_out_of_sync(cpu, policy->cur, ret); 882 cpufreq_out_of_sync(cpu, policy->cur, ret);
@@ -881,7 +886,7 @@ unsigned int cpufreq_get(unsigned int cpu)
881 886
882 mutex_unlock(&policy->lock); 887 mutex_unlock(&policy->lock);
883 888
884 out: 889out:
885 cpufreq_cpu_put(policy); 890 cpufreq_cpu_put(policy);
886 891
887 return (ret); 892 return (ret);
@@ -962,7 +967,7 @@ static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
962 cpu_policy->cur = cur_freq; 967 cpu_policy->cur = cur_freq;
963 } 968 }
964 969
965 out: 970out:
966 cpufreq_cpu_put(cpu_policy); 971 cpufreq_cpu_put(cpu_policy);
967 return 0; 972 return 0;
968} 973}
@@ -1169,7 +1174,6 @@ int cpufreq_driver_target(struct cpufreq_policy *policy,
1169 mutex_unlock(&policy->lock); 1174 mutex_unlock(&policy->lock);
1170 1175
1171 cpufreq_cpu_put(policy); 1176 cpufreq_cpu_put(policy);
1172
1173 return ret; 1177 return ret;
1174} 1178}
1175EXPORT_SYMBOL_GPL(cpufreq_driver_target); 1179EXPORT_SYMBOL_GPL(cpufreq_driver_target);
@@ -1208,7 +1212,6 @@ int cpufreq_governor(unsigned int cpu, unsigned int event)
1208 mutex_unlock(&policy->lock); 1212 mutex_unlock(&policy->lock);
1209 1213
1210 cpufreq_cpu_put(policy); 1214 cpufreq_cpu_put(policy);
1211
1212 return ret; 1215 return ret;
1213} 1216}
1214EXPORT_SYMBOL_GPL(cpufreq_governor); 1217EXPORT_SYMBOL_GPL(cpufreq_governor);
@@ -1232,7 +1235,6 @@ int cpufreq_register_governor(struct cpufreq_governor *governor)
1232 list_add(&governor->governor_list, &cpufreq_governor_list); 1235 list_add(&governor->governor_list, &cpufreq_governor_list);
1233 1236
1234 mutex_unlock(&cpufreq_governor_mutex); 1237 mutex_unlock(&cpufreq_governor_mutex);
1235
1236 return 0; 1238 return 0;
1237} 1239}
1238EXPORT_SYMBOL_GPL(cpufreq_register_governor); 1240EXPORT_SYMBOL_GPL(cpufreq_register_governor);
@@ -1277,7 +1279,6 @@ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
1277 mutex_unlock(&cpu_policy->lock); 1279 mutex_unlock(&cpu_policy->lock);
1278 1280
1279 cpufreq_cpu_put(cpu_policy); 1281 cpufreq_cpu_put(cpu_policy);
1280
1281 return 0; 1282 return 0;
1282} 1283}
1283EXPORT_SYMBOL(cpufreq_get_policy); 1284EXPORT_SYMBOL(cpufreq_get_policy);
@@ -1291,9 +1292,7 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
1291 dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu, 1292 dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
1292 policy->min, policy->max); 1293 policy->min, policy->max);
1293 1294
1294 memcpy(&policy->cpuinfo, 1295 memcpy(&policy->cpuinfo, &data->cpuinfo, sizeof(struct cpufreq_cpuinfo));
1295 &data->cpuinfo,
1296 sizeof(struct cpufreq_cpuinfo));
1297 1296
1298 /* verify the cpu speed can be set within this limit */ 1297 /* verify the cpu speed can be set within this limit */
1299 ret = cpufreq_driver->verify(policy); 1298 ret = cpufreq_driver->verify(policy);
@@ -1324,8 +1323,8 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
1324 1323
1325 up_read(&cpufreq_notifier_rwsem); 1324 up_read(&cpufreq_notifier_rwsem);
1326 1325
1327 data->min = policy->min; 1326 data->min = policy->min;
1328 data->max = policy->max; 1327 data->max = policy->max;
1329 1328
1330 dprintk("new min and max freqs are %u - %u kHz\n", data->min, data->max); 1329 dprintk("new min and max freqs are %u - %u kHz\n", data->min, data->max);
1331 1330
@@ -1362,7 +1361,7 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
1362 __cpufreq_governor(data, CPUFREQ_GOV_LIMITS); 1361 __cpufreq_governor(data, CPUFREQ_GOV_LIMITS);
1363 } 1362 }
1364 1363
1365 error_out: 1364error_out:
1366 cpufreq_debug_enable_ratelimit(); 1365 cpufreq_debug_enable_ratelimit();
1367 return ret; 1366 return ret;
1368} 1367}
@@ -1421,9 +1420,7 @@ int cpufreq_update_policy(unsigned int cpu)
1421 mutex_lock(&data->lock); 1420 mutex_lock(&data->lock);
1422 1421
1423 dprintk("updating policy for CPU %u\n", cpu); 1422 dprintk("updating policy for CPU %u\n", cpu);
1424 memcpy(&policy, 1423 memcpy(&policy, data, sizeof(struct cpufreq_policy));
1425 data,
1426 sizeof(struct cpufreq_policy));
1427 policy.min = data->user_policy.min; 1424 policy.min = data->user_policy.min;
1428 policy.max = data->user_policy.max; 1425 policy.max = data->user_policy.max;
1429 policy.policy = data->user_policy.policy; 1426 policy.policy = data->user_policy.policy;
@@ -1433,8 +1430,13 @@ int cpufreq_update_policy(unsigned int cpu)
1433 -> ask driver for current freq and notify governors about a change */ 1430 -> ask driver for current freq and notify governors about a change */
1434 if (cpufreq_driver->get) { 1431 if (cpufreq_driver->get) {
1435 policy.cur = cpufreq_driver->get(cpu); 1432 policy.cur = cpufreq_driver->get(cpu);
1436 if (data->cur != policy.cur) 1433 if (!data->cur) {
1437 cpufreq_out_of_sync(cpu, data->cur, policy.cur); 1434 dprintk("Driver did not initialize current freq");
1435 data->cur = policy.cur;
1436 } else {
1437 if (data->cur != policy.cur)
1438 cpufreq_out_of_sync(cpu, data->cur, policy.cur);
1439 }
1438 } 1440 }
1439 1441
1440 ret = __cpufreq_set_policy(data, &policy); 1442 ret = __cpufreq_set_policy(data, &policy);