* Copyright (C) 2001 Russell King
* (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
*
+ * Oct 2005 - Ashok Raj <ashok.raj@intel.com>
+ * Added handling for CPU hotplug
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/completion.h>
+#include <linux/mutex.h>
#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "cpufreq-core", msg)
* level driver of CPUFreq support, and its spinlock. This lock
* also protects the cpufreq_cpu_data array.
*/
-static struct cpufreq_driver *cpufreq_driver;
-static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
-static spinlock_t cpufreq_driver_lock = SPIN_LOCK_UNLOCKED;
-
-
-/* we keep a copy of all ->add'ed CPU's struct sys_device here;
- * as it is only accessed in ->add and ->remove, no lock or reference
- * count is necessary.
- */
-static struct sys_device *cpu_sys_devices[NR_CPUS];
-
+static struct cpufreq_driver *cpufreq_driver;
+static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
+static DEFINE_SPINLOCK(cpufreq_driver_lock);
/* internal prototypes */
static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
static void handle_update(void *data);
-static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci);
/**
* Two notifier lists: the "policy" list is involved in the
* changes to devices when the CPU clock speed changes.
* The mutex locks both lists.
*/
-static struct notifier_block *cpufreq_policy_notifier_list;
-static struct notifier_block *cpufreq_transition_notifier_list;
-static DECLARE_RWSEM (cpufreq_notifier_rwsem);
+static struct notifier_block *cpufreq_policy_notifier_list;
+static struct notifier_block *cpufreq_transition_notifier_list;
+static DECLARE_RWSEM (cpufreq_notifier_rwsem);
static LIST_HEAD(cpufreq_governor_list);
-static DECLARE_MUTEX (cpufreq_governor_sem);
+static DEFINE_MUTEX (cpufreq_governor_mutex);
-static struct cpufreq_policy * cpufreq_cpu_get(unsigned int cpu)
+struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
{
struct cpufreq_policy *data;
unsigned long flags;
if (!kobject_get(&data->kobj))
goto err_out_put_module;
-
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
-
return data;
- err_out_put_module:
+err_out_put_module:
module_put(cpufreq_driver->owner);
- err_out_unlock:
+err_out_unlock:
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
- err_out:
+err_out:
return NULL;
}
+EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
-static void cpufreq_cpu_put(struct cpufreq_policy *data)
+
+void cpufreq_cpu_put(struct cpufreq_policy *data)
{
kobject_put(&data->kobj);
module_put(cpufreq_driver->owner);
}
+EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
/*********************************************************************
* is set, and disabled upon cpufreq driver removal
*/
static unsigned int disable_ratelimit = 1;
-static spinlock_t disable_ratelimit_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(disable_ratelimit_lock);
-static inline void cpufreq_debug_enable_ratelimit(void)
+static void cpufreq_debug_enable_ratelimit(void)
{
unsigned long flags;
spin_unlock_irqrestore(&disable_ratelimit_lock, flags);
}
-static inline void cpufreq_debug_disable_ratelimit(void)
+static void cpufreq_debug_disable_ratelimit(void)
{
unsigned long flags;
static unsigned long l_p_j_ref;
static unsigned int l_p_j_ref_freq;
-static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
+static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
{
if (ci->flags & CPUFREQ_CONST_LOOPS)
return;
}
if ((val == CPUFREQ_PRECHANGE && ci->old < ci->new) ||
(val == CPUFREQ_POSTCHANGE && ci->old > ci->new) ||
- (val == CPUFREQ_RESUMECHANGE)) {
+ (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) {
loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, ci->new);
dprintk("scaling loops_per_jiffy to %lu for frequency %u kHz\n", loops_per_jiffy, ci->new);
}
/**
- * cpufreq_notify_transition - call notifier chain and adjust_jiffies on frequency transition
+ * cpufreq_notify_transition - call notifier chain and adjust_jiffies
+ * on frequency transition.
*
- * This function calls the transition notifiers and the "adjust_jiffies" function. It is called
- * twice on all CPU frequency changes that have external effects.
+ * This function calls the transition notifiers and the "adjust_jiffies"
+ * function. It is called twice on all CPU frequency changes that have
+ * external effects.
*/
void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
{
+ struct cpufreq_policy *policy;
+
BUG_ON(irqs_disabled());
freqs->flags = cpufreq_driver->flags;
- dprintk("notification %u of frequency transition to %u kHz\n", state, freqs->new);
+ dprintk("notification %u of frequency transition to %u kHz\n",
+ state, freqs->new);
down_read(&cpufreq_notifier_rwsem);
+
+ policy = cpufreq_cpu_data[freqs->cpu];
switch (state) {
+
case CPUFREQ_PRECHANGE:
- /* detect if the driver reported a value as "old frequency" which
- * is not equal to what the cpufreq core thinks is "old frequency".
+ /* detect if the driver reported a value as "old frequency"
+ * which is not equal to what the cpufreq core thinks is
+ * "old frequency".
*/
if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
- if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cur)) &&
- (unlikely(freqs->old != cpufreq_cpu_data[freqs->cpu]->cur)))
- {
- printk(KERN_WARNING "Warning: CPU frequency is %u, "
- "cpufreq assumed %u kHz.\n", freqs->old, cpufreq_cpu_data[freqs->cpu]->cur);
- freqs->old = cpufreq_cpu_data[freqs->cpu]->cur;
+ if ((policy) && (policy->cpu == freqs->cpu) &&
+ (policy->cur) && (policy->cur != freqs->old)) {
+ dprintk(KERN_WARNING "Warning: CPU frequency is"
+ " %u, cpufreq assumed %u kHz.\n",
+ freqs->old, policy->cur);
+ freqs->old = policy->cur;
}
}
- notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_PRECHANGE, freqs);
+ notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_PRECHANGE, freqs);
adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
break;
+
case CPUFREQ_POSTCHANGE:
adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
- notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_POSTCHANGE, freqs);
- if ((likely(cpufreq_cpu_data[freqs->cpu])) &&
- (likely(cpufreq_cpu_data[freqs->cpu]->cpu == freqs->cpu)))
- cpufreq_cpu_data[freqs->cpu]->cur = freqs->new;
+ notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_POSTCHANGE, freqs);
+ if (likely(policy) && likely(policy->cpu == freqs->cpu))
+ policy->cur = freqs->new;
break;
}
up_read(&cpufreq_notifier_rwsem);
/**
* cpufreq_parse_governor - parse a governor string
*/
-int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
+static int cpufreq_parse_governor (char *str_governor, unsigned int *policy,
struct cpufreq_governor **governor)
{
if (!cpufreq_driver)
return -EINVAL;
} else {
struct cpufreq_governor *t;
- down(&cpufreq_governor_sem);
+ mutex_lock(&cpufreq_governor_mutex);
if (!cpufreq_driver || !cpufreq_driver->target)
goto out;
list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
if (!strnicmp(str_governor,t->name,CPUFREQ_NAME_LEN)) {
*governor = t;
- up(&cpufreq_governor_sem);
+ mutex_unlock(&cpufreq_governor_mutex);
return 0;
}
}
- out:
- up(&cpufreq_governor_sem);
+out:
+ mutex_unlock(&cpufreq_governor_mutex);
}
return -EINVAL;
}
return -EINVAL;
ret = cpufreq_set_policy(&new_policy);
-
return ret ? ret : count;
}
goto out;
i += scnprintf(&buf[i], CPUFREQ_NAME_LEN, "%s ", t->name);
}
- out:
+out:
i += sprintf(&buf[i], "\n");
return i;
}
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
- ret = fattr->show ? fattr->show(policy,buf) : 0;
+ ret = fattr->show ? fattr->show(policy,buf) : -EIO;
cpufreq_cpu_put(policy);
return ret;
}
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
- ret = fattr->store ? fattr->store(policy,buf,count) : 0;
+ ret = fattr->store ? fattr->store(policy,buf,count) : -EIO;
cpufreq_cpu_put(policy);
return ret;
}
unsigned long flags;
unsigned int j;
+ if (cpu_is_offline(cpu))
+ return 0;
+
cpufreq_debug_disable_ratelimit();
dprintk("adding CPU %u\n", cpu);
* CPU because it is in the same boat. */
policy = cpufreq_cpu_get(cpu);
if (unlikely(policy)) {
- cpu_sys_devices[cpu] = sys_dev;
dprintk("CPU already managed, adding link\n");
sysfs_create_link(&sys_dev->kobj, &policy->kobj, "cpufreq");
cpufreq_debug_enable_ratelimit();
goto module_out;
}
- policy = kmalloc(sizeof(struct cpufreq_policy), GFP_KERNEL);
+ policy = kzalloc(sizeof(struct cpufreq_policy), GFP_KERNEL);
if (!policy) {
ret = -ENOMEM;
goto nomem_out;
}
- memset(policy, 0, sizeof(struct cpufreq_policy));
policy->cpu = cpu;
policy->cpus = cpumask_of_cpu(cpu);
- init_MUTEX_LOCKED(&policy->lock);
+ mutex_init(&policy->lock);
+ mutex_lock(&policy->lock);
init_completion(&policy->kobj_unregister);
INIT_WORK(&policy->update, handle_update, (void *)(long)cpu);
ret = cpufreq_driver->init(policy);
if (ret) {
dprintk("initialization failed\n");
+ mutex_unlock(&policy->lock);
goto err_out;
}
strlcpy(policy->kobj.name, "cpufreq", KOBJ_NAME_LEN);
ret = kobject_register(&policy->kobj);
- if (ret)
- goto err_out;
-
+ if (ret) {
+ mutex_unlock(&policy->lock);
+ goto err_out_driver_exit;
+ }
/* set up files for this cpu device */
drv_attr = cpufreq_driver->attr;
while ((drv_attr) && (*drv_attr)) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
policy->governor = NULL; /* to assure that the starting sequence is
* run in cpufreq_set_policy */
- up(&policy->lock);
+ mutex_unlock(&policy->lock);
/* set default policy */
}
module_put(cpufreq_driver->owner);
- cpu_sys_devices[cpu] = sys_dev;
dprintk("initialization complete\n");
cpufreq_debug_enable_ratelimit();
kobject_unregister(&policy->kobj);
wait_for_completion(&policy->kobj_unregister);
+err_out_driver_exit:
+ if (cpufreq_driver->exit)
+ cpufreq_driver->exit(policy);
+
err_out:
kfree(policy);
nomem_out:
module_put(cpufreq_driver->owner);
- module_out:
+module_out:
cpufreq_debug_enable_ratelimit();
return ret;
}
unsigned long flags;
struct cpufreq_policy *data;
#ifdef CONFIG_SMP
+ struct sys_device *cpu_sys_dev;
unsigned int j;
#endif
if (!data) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
- cpu_sys_devices[cpu] = NULL;
cpufreq_debug_enable_ratelimit();
return -EINVAL;
}
dprintk("removing link\n");
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
sysfs_remove_link(&sys_dev->kobj, "cpufreq");
- cpu_sys_devices[cpu] = NULL;
cpufreq_cpu_put(data);
cpufreq_debug_enable_ratelimit();
return 0;
}
#endif
- cpu_sys_devices[cpu] = NULL;
if (!kobject_get(&data->kobj)) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
if (j == cpu)
continue;
dprintk("removing link for cpu %u\n", j);
- sysfs_remove_link(&cpu_sys_devices[j]->kobj, "cpufreq");
+ cpu_sys_dev = get_cpu_sysdev(j);
+ sysfs_remove_link(&cpu_sys_dev->kobj, "cpufreq");
cpufreq_cpu_put(data);
}
}
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
#endif
+ mutex_lock(&data->lock);
if (cpufreq_driver->target)
__cpufreq_governor(data, CPUFREQ_GOV_STOP);
+ mutex_unlock(&data->lock);
kobject_unregister(&data->kobj);
kfree(data);
cpufreq_debug_enable_ratelimit();
-
return 0;
}
{
struct cpufreq_freqs freqs;
- printk(KERN_WARNING "Warning: CPU frequency out of sync: cpufreq and timing "
+ dprintk(KERN_WARNING "Warning: CPU frequency out of sync: cpufreq and timing "
"core thinks of %u, is %u kHz.\n", old_freq, new_freq);
freqs.cpu = cpu;
}
+/**
+ * cpufreq_quick_get - get the CPU frequency (in kHz) frpm policy->cur
+ * @cpu: CPU number
+ *
+ * This is the last known freq, without actually getting it from the driver.
+ * Return value will be same as what is shown in scaling_cur_freq in sysfs.
+ */
+unsigned int cpufreq_quick_get(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ unsigned int ret = 0;
+
+ if (policy) {
+ mutex_lock(&policy->lock);
+ ret = policy->cur;
+ mutex_unlock(&policy->lock);
+ cpufreq_cpu_put(policy);
+ }
+
+ return (ret);
+}
+EXPORT_SYMBOL(cpufreq_quick_get);
+
+
/**
* cpufreq_get - get the current CPU frequency (in kHz)
* @cpu: CPU number
if (!cpufreq_driver->get)
goto out;
- down(&policy->lock);
+ mutex_lock(&policy->lock);
ret = cpufreq_driver->get(cpu);
- if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS))
- {
+ if (ret && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
/* verify no discrepancy between actual and saved value exists */
if (unlikely(ret != policy->cur)) {
cpufreq_out_of_sync(cpu, policy->cur, ret);
}
}
- up(&policy->lock);
+ mutex_unlock(&policy->lock);
- out:
+out:
cpufreq_cpu_put(policy);
return (ret);
EXPORT_SYMBOL(cpufreq_get);
+/**
+ * cpufreq_suspend - let the low level driver prepare for suspend
+ */
+
+static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
+{
+ int cpu = sysdev->id;
+ unsigned int ret = 0;
+ unsigned int cur_freq = 0;
+ struct cpufreq_policy *cpu_policy;
+
+ dprintk("resuming cpu %u\n", cpu);
+
+ if (!cpu_online(cpu))
+ return 0;
+
+ /* we may be lax here as interrupts are off. Nonetheless
+ * we need to grab the correct cpu policy, as to check
+ * whether we really run on this CPU.
+ */
+
+ cpu_policy = cpufreq_cpu_get(cpu);
+ if (!cpu_policy)
+ return -EINVAL;
+
+ /* only handle each CPU group once */
+ if (unlikely(cpu_policy->cpu != cpu)) {
+ cpufreq_cpu_put(cpu_policy);
+ return 0;
+ }
+
+ if (cpufreq_driver->suspend) {
+ ret = cpufreq_driver->suspend(cpu_policy, pmsg);
+ if (ret) {
+ printk(KERN_ERR "cpufreq: suspend failed in ->suspend "
+ "step on CPU %u\n", cpu_policy->cpu);
+ cpufreq_cpu_put(cpu_policy);
+ return ret;
+ }
+ }
+
+
+ if (cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)
+ goto out;
+
+ if (cpufreq_driver->get)
+ cur_freq = cpufreq_driver->get(cpu_policy->cpu);
+
+ if (!cur_freq || !cpu_policy->cur) {
+ printk(KERN_ERR "cpufreq: suspend failed to assert current "
+ "frequency is what timing core thinks it is.\n");
+ goto out;
+ }
+
+ if (unlikely(cur_freq != cpu_policy->cur)) {
+ struct cpufreq_freqs freqs;
+
+ if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
+ dprintk(KERN_DEBUG "Warning: CPU frequency is %u, "
+ "cpufreq assumed %u kHz.\n",
+ cur_freq, cpu_policy->cur);
+
+ freqs.cpu = cpu;
+ freqs.old = cpu_policy->cur;
+ freqs.new = cur_freq;
+
+ notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_SUSPENDCHANGE, &freqs);
+ adjust_jiffies(CPUFREQ_SUSPENDCHANGE, &freqs);
+
+ cpu_policy->cur = cur_freq;
+ }
+
+out:
+ cpufreq_cpu_put(cpu_policy);
+ return 0;
+}
+
/**
* cpufreq_resume - restore proper CPU frequency handling after resume
*
* 1.) resume CPUfreq hardware support (cpufreq_driver->resume())
* 2.) if ->target and !CPUFREQ_CONST_LOOPS: verify we're in sync
- * 3.) schedule call cpufreq_update_policy() ASAP as interrupts are restored.
+ * 3.) schedule call cpufreq_update_policy() ASAP as interrupts are
+ * restored.
*/
static int cpufreq_resume(struct sys_device * sysdev)
{
return 0;
}
+ if (cpufreq_driver->resume) {
+ ret = cpufreq_driver->resume(cpu_policy);
+ if (ret) {
+ printk(KERN_ERR "cpufreq: resume failed in ->resume "
+ "step on CPU %u\n", cpu_policy->cpu);
+ cpufreq_cpu_put(cpu_policy);
+ return ret;
+ }
+ }
+
if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
unsigned int cur_freq = 0;
cur_freq = cpufreq_driver->get(cpu_policy->cpu);
if (!cur_freq || !cpu_policy->cur) {
- printk(KERN_ERR "cpufreq: resume failed to assert current frequency is what timing core thinks it is.\n");
+ printk(KERN_ERR "cpufreq: resume failed to assert "
+ "current frequency is what timing core "
+ "thinks it is.\n");
goto out;
}
if (unlikely(cur_freq != cpu_policy->cur)) {
struct cpufreq_freqs freqs;
- printk(KERN_WARNING "Warning: CPU frequency is %u, "
- "cpufreq assumed %u kHz.\n", cur_freq, cpu_policy->cur);
+ if (!(cpufreq_driver->flags & CPUFREQ_PM_NO_WARN))
+ dprintk(KERN_WARNING "Warning: CPU frequency"
+ "is %u, cpufreq assumed %u kHz.\n",
+ cur_freq, cpu_policy->cur);
freqs.cpu = cpu;
freqs.old = cpu_policy->cur;
freqs.new = cur_freq;
- notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_RESUMECHANGE, &freqs);
+ notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_RESUMECHANGE, &freqs);
adjust_jiffies(CPUFREQ_RESUMECHANGE, &freqs);
cpu_policy->cur = cur_freq;
static struct sysdev_driver cpufreq_sysdev_driver = {
.add = cpufreq_add_dev,
.remove = cpufreq_remove_dev,
+ .suspend = cpufreq_suspend,
.resume = cpufreq_resume,
};
unsigned int relation)
{
int retval = -EINVAL;
+
lock_cpu_hotplug();
dprintk("target for CPU %u: %u kHz, relation %u\n", policy->cpu,
target_freq, relation);
- if (cpu_online(policy->cpu))
+ if (cpu_online(policy->cpu) && cpufreq_driver->target)
retval = cpufreq_driver->target(policy, target_freq, relation);
+
unlock_cpu_hotplug();
+
return retval;
}
EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
-
int cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
- unsigned int ret;
+ int ret;
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
- down(&policy->lock);
+ mutex_lock(&policy->lock);
ret = __cpufreq_driver_target(policy, target_freq, relation);
- up(&policy->lock);
+ mutex_unlock(&policy->lock);
cpufreq_cpu_put(policy);
-
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
{
- int ret = -EINVAL;
+ int ret;
if (!try_module_get(policy->governor->owner))
return -EINVAL;
if (!policy)
return -EINVAL;
- down(&policy->lock);
+ mutex_lock(&policy->lock);
ret = __cpufreq_governor(policy, event);
- up(&policy->lock);
+ mutex_unlock(&policy->lock);
cpufreq_cpu_put(policy);
-
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_governor);
if (!governor)
return -EINVAL;
- down(&cpufreq_governor_sem);
+ mutex_lock(&cpufreq_governor_mutex);
list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
if (!strnicmp(governor->name,t->name,CPUFREQ_NAME_LEN)) {
- up(&cpufreq_governor_sem);
+ mutex_unlock(&cpufreq_governor_mutex);
return -EBUSY;
}
}
list_add(&governor->governor_list, &cpufreq_governor_list);
- up(&cpufreq_governor_sem);
-
+ mutex_unlock(&cpufreq_governor_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_register_governor);
if (!governor)
return;
- down(&cpufreq_governor_sem);
+ mutex_lock(&cpufreq_governor_mutex);
list_del(&governor->governor_list);
- up(&cpufreq_governor_sem);
+ mutex_unlock(&cpufreq_governor_mutex);
return;
}
EXPORT_SYMBOL_GPL(cpufreq_unregister_governor);
if (!cpu_policy)
return -EINVAL;
- down(&cpu_policy->lock);
+ mutex_lock(&cpu_policy->lock);
memcpy(policy, cpu_policy, sizeof(struct cpufreq_policy));
- up(&cpu_policy->lock);
+ mutex_unlock(&cpu_policy->lock);
cpufreq_cpu_put(cpu_policy);
-
return 0;
}
EXPORT_SYMBOL(cpufreq_get_policy);
dprintk("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
policy->min, policy->max);
- memcpy(&policy->cpuinfo,
- &data->cpuinfo,
- sizeof(struct cpufreq_cpuinfo));
+ memcpy(&policy->cpuinfo, &data->cpuinfo, sizeof(struct cpufreq_cpuinfo));
/* verify the cpu speed can be set within this limit */
ret = cpufreq_driver->verify(policy);
up_read(&cpufreq_notifier_rwsem);
- data->min = policy->min;
- data->max = policy->max;
+ data->min = policy->min;
+ data->max = policy->max;
dprintk("new min and max freqs are %u - %u kHz\n", data->min, data->max);
__cpufreq_governor(data, CPUFREQ_GOV_LIMITS);
}
- error_out:
+error_out:
cpufreq_debug_enable_ratelimit();
return ret;
}
return -EINVAL;
/* lock this CPU */
- down(&data->lock);
+ mutex_lock(&data->lock);
ret = __cpufreq_set_policy(data, policy);
data->user_policy.min = data->min;
data->user_policy.policy = data->policy;
data->user_policy.governor = data->governor;
- up(&data->lock);
+ mutex_unlock(&data->lock);
cpufreq_cpu_put(data);
return ret;
if (!data)
return -ENODEV;
- down(&data->lock);
+ mutex_lock(&data->lock);
dprintk("updating policy for CPU %u\n", cpu);
- memcpy(&policy,
- data,
- sizeof(struct cpufreq_policy));
+ memcpy(&policy, data, sizeof(struct cpufreq_policy));
policy.min = data->user_policy.min;
policy.max = data->user_policy.max;
policy.policy = data->user_policy.policy;
policy.governor = data->user_policy.governor;
+ /* BIOS might change freq behind our back
+ -> ask driver for current freq and notify governors about a change */
+ if (cpufreq_driver->get) {
+ policy.cur = cpufreq_driver->get(cpu);
+ if (!data->cur) {
+ dprintk("Driver did not initialize current freq");
+ data->cur = policy.cur;
+ } else {
+ if (data->cur != policy.cur)
+ cpufreq_out_of_sync(cpu, data->cur, policy.cur);
+ }
+ }
+
ret = __cpufreq_set_policy(data, &policy);
- up(&data->lock);
+ mutex_unlock(&data->lock);
cpufreq_cpu_put(data);
return ret;
}
EXPORT_SYMBOL(cpufreq_update_policy);
+static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+ struct cpufreq_policy *policy;
+ struct sys_device *sys_dev;
+
+ sys_dev = get_cpu_sysdev(cpu);
+
+ if (sys_dev) {
+ switch (action) {
+ case CPU_ONLINE:
+ cpufreq_add_dev(sys_dev);
+ break;
+ case CPU_DOWN_PREPARE:
+ /*
+ * We attempt to put this cpu in lowest frequency
+ * possible before going down. This will permit
+ * hardware-managed P-State to switch other related
+ * threads to min or higher speeds if possible.
+ */
+ policy = cpufreq_cpu_data[cpu];
+ if (policy) {
+ cpufreq_driver_target(policy, policy->min,
+ CPUFREQ_RELATION_H);
+ }
+ break;
+ case CPU_DEAD:
+ cpufreq_remove_dev(sys_dev);
+ break;
+ }
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block cpufreq_cpu_notifier =
+{
+ .notifier_call = cpufreq_cpu_callback,
+};
/*********************************************************************
* REGISTER / UNREGISTER CPUFREQ DRIVER *
}
if (!ret) {
+ register_cpu_notifier(&cpufreq_cpu_notifier);
dprintk("driver %s up and running\n", driver_data->name);
cpufreq_debug_enable_ratelimit();
}
dprintk("unregistering driver %s\n", driver->name);
sysdev_driver_unregister(&cpu_sysdev_class, &cpufreq_sysdev_driver);
+ unregister_cpu_notifier(&cpufreq_cpu_notifier);
spin_lock_irqsave(&cpufreq_driver_lock, flags);
cpufreq_driver = NULL;