*
* Copyright (C) 2001 Russell King
* (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
+ * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org>
*
* 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.
- *
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <asm/cputime.h>
#include <linux/kernel.h>
+#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/notifier.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
+#include <linux/tick.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/cpu.h>
*/
static struct cpufreq_driver *cpufreq_driver;
static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
+static DEFINE_RWLOCK(cpufreq_driver_lock);
+static DEFINE_MUTEX(cpufreq_governor_lock);
+
#ifdef CONFIG_HOTPLUG_CPU
/* This one keeps track of the previously set governor of a removed CPU */
static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor);
#endif
-static DEFINE_RWLOCK(cpufreq_driver_lock);
/*
* cpu_policy_rwsem is a per CPU reader-writer semaphore designed to cure
{
return cpufreq_driver->have_governor_per_policy;
}
+EXPORT_SYMBOL_GPL(have_governor_per_policy);
+
+struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy)
+{
+ if (have_governor_per_policy())
+ return &policy->kobj;
+ else
+ return cpufreq_global_kobject;
+}
+EXPORT_SYMBOL_GPL(get_governor_parent_kobj);
+
+static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
+{
+ u64 idle_time;
+ u64 cur_wall_time;
+ u64 busy_time;
+
+ cur_wall_time = jiffies64_to_cputime64(get_jiffies_64());
+
+ busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE];
+
+ idle_time = cur_wall_time - busy_time;
+ if (wall)
+ *wall = cputime_to_usecs(cur_wall_time);
+
+ return cputime_to_usecs(idle_time);
+}
+
+u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy)
+{
+ u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL);
+
+ if (idle_time == -1ULL)
+ return get_cpu_idle_time_jiffy(cpu, wall);
+ else if (!io_busy)
+ idle_time += get_cpu_iowait_time_us(cpu, wall);
+
+ return idle_time;
+}
+EXPORT_SYMBOL_GPL(get_cpu_idle_time);
static struct cpufreq_policy *__cpufreq_cpu_get(unsigned int cpu, bool sysfs)
{
if (!try_module_get(cpufreq_driver->owner))
goto err_out_unlock;
-
/* get the CPU */
data = per_cpu(cpufreq_cpu_data, cpu);
*/
#ifndef CONFIG_SMP
static unsigned long l_p_j_ref;
-static unsigned int l_p_j_ref_freq;
+static unsigned int l_p_j_ref_freq;
static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
{
pr_debug("saving %lu as reference value for loops_per_jiffy; "
"freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq);
}
- if ((val == CPUFREQ_POSTCHANGE && ci->old != ci->new) ||
+ if ((val == CPUFREQ_POSTCHANGE && ci->old != ci->new) ||
(val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) {
loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
ci->new);
}
#endif
-
-void __cpufreq_notify_transition(struct cpufreq_policy *policy,
+static void __cpufreq_notify_transition(struct cpufreq_policy *policy,
struct cpufreq_freqs *freqs, unsigned int state)
{
BUG_ON(irqs_disabled());
break;
}
}
+
/**
* cpufreq_notify_transition - call notifier chain and adjust_jiffies
* on frequency transition.
EXPORT_SYMBOL_GPL(cpufreq_notify_transition);
-
/*********************************************************************
* SYSFS INTERFACE *
*********************************************************************/
return err;
}
-
/**
* cpufreq_per_cpu_attr_read() / show_##file_name() -
* print out cpufreq information
return sprintf(buf, "%u\n", cur_freq);
}
-
/**
* show_scaling_governor - show the current policy for the specified CPU
*/
return -EINVAL;
}
-
/**
* store_scaling_governor - store policy for the specified CPU
*/
&new_policy.governor))
return -EINVAL;
- /* Do not use cpufreq_set_policy here or the user_policy.max
- will be wrongly overridden */
+ /*
+ * Do not use cpufreq_set_policy here or the user_policy.max
+ * will be wrongly overridden
+ */
ret = __cpufreq_set_policy(policy, &new_policy);
policy->user_policy.policy = policy->policy;
NULL
};
-struct kobject *cpufreq_global_kobject;
-EXPORT_SYMBOL(cpufreq_global_kobject);
-
#define to_policy(k) container_of(k, struct cpufreq_policy, kobj)
#define to_attr(a) container_of(a, struct freq_attr, attr)
.release = cpufreq_sysfs_release,
};
+struct kobject *cpufreq_global_kobject;
+EXPORT_SYMBOL(cpufreq_global_kobject);
+
+static int cpufreq_global_kobject_usage;
+
+int cpufreq_get_global_kobject(void)
+{
+ if (!cpufreq_global_kobject_usage++)
+ return kobject_add(cpufreq_global_kobject,
+ &cpu_subsys.dev_root->kobj, "%s", "cpufreq");
+
+ return 0;
+}
+EXPORT_SYMBOL(cpufreq_get_global_kobject);
+
+void cpufreq_put_global_kobject(void)
+{
+ if (!--cpufreq_global_kobject_usage)
+ kobject_del(cpufreq_global_kobject);
+}
+EXPORT_SYMBOL(cpufreq_put_global_kobject);
+
+int cpufreq_sysfs_create_file(const struct attribute *attr)
+{
+ int ret = cpufreq_get_global_kobject();
+
+ if (!ret) {
+ ret = sysfs_create_file(cpufreq_global_kobject, attr);
+ if (ret)
+ cpufreq_put_global_kobject();
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(cpufreq_sysfs_create_file);
+
+void cpufreq_sysfs_remove_file(const struct attribute *attr)
+{
+ sysfs_remove_file(cpufreq_global_kobject, attr);
+ cpufreq_put_global_kobject();
+}
+EXPORT_SYMBOL(cpufreq_sysfs_remove_file);
+
/* symlink affected CPUs */
static int cpufreq_add_dev_symlink(unsigned int cpu,
struct cpufreq_policy *policy)
* Caller should already have policy_rwsem in write mode for this CPU.
* This routine frees the rwsem before returning.
*/
-static int __cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
+static int __cpufreq_remove_dev(struct device *dev,
+ struct subsys_interface *sif)
{
unsigned int cpu = dev->id, ret, cpus;
unsigned long flags;
return 0;
}
-
static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
{
unsigned int cpu = dev->id;
return retval;
}
-
static void handle_update(struct work_struct *work)
{
struct cpufreq_policy *policy =
}
/**
- * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're in deep trouble.
+ * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're
+ * in deep trouble.
* @cpu: cpu number
* @old_freq: CPU frequency the kernel thinks the CPU runs at
* @new_freq: CPU frequency the CPU actually runs at
struct cpufreq_freqs freqs;
unsigned long flags;
-
pr_debug("Warning: CPU frequency out of sync: cpufreq and timing "
"core thinks of %u, is %u kHz.\n", old_freq, new_freq);
cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
}
-
/**
* cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur
* @cpu: CPU number
}
EXPORT_SYMBOL(cpufreq_quick_get_max);
-
static unsigned int __cpufreq_get(unsigned int cpu)
{
struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
.remove_dev = cpufreq_remove_dev,
};
-
/**
* cpufreq_bp_suspend - Prepare the boot CPU for system suspend.
*
}
EXPORT_SYMBOL(cpufreq_register_notifier);
-
/**
* cpufreq_unregister_notifier - unregister a driver with cpufreq
* @nb: notifier block to be unregistered
- * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
+ * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
*
* Remove a driver from the CPU frequency notifier list.
*
* GOVERNORS *
*********************************************************************/
-
int __cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
int ret = -EINVAL;
- policy = cpufreq_cpu_get(policy->cpu);
- if (!policy)
- goto no_policy;
-
if (unlikely(lock_policy_rwsem_write(policy->cpu)))
goto fail;
unlock_policy_rwsem_write(policy->cpu);
fail:
- cpufreq_cpu_put(policy);
-no_policy:
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
int __cpufreq_driver_getavg(struct cpufreq_policy *policy, unsigned int cpu)
{
- int ret = 0;
-
if (cpufreq_disabled())
- return ret;
+ return 0;
if (!cpufreq_driver->getavg)
return 0;
- policy = cpufreq_cpu_get(policy->cpu);
- if (!policy)
- return -EINVAL;
-
- ret = cpufreq_driver->getavg(policy, cpu);
-
- cpufreq_cpu_put(policy);
- return ret;
+ return cpufreq_driver->getavg(policy, cpu);
}
EXPORT_SYMBOL_GPL(__cpufreq_driver_getavg);
pr_debug("__cpufreq_governor for CPU %u, event %u\n",
policy->cpu, event);
+
+ mutex_lock(&cpufreq_governor_lock);
+ if ((!policy->governor_enabled && (event == CPUFREQ_GOV_STOP)) ||
+ (policy->governor_enabled && (event == CPUFREQ_GOV_START))) {
+ mutex_unlock(&cpufreq_governor_lock);
+ return -EBUSY;
+ }
+
+ if (event == CPUFREQ_GOV_STOP)
+ policy->governor_enabled = false;
+ else if (event == CPUFREQ_GOV_START)
+ policy->governor_enabled = true;
+
+ mutex_unlock(&cpufreq_governor_lock);
+
ret = policy->governor->governor(policy, event);
if (!ret) {
policy->governor->initialized++;
else if (event == CPUFREQ_GOV_POLICY_EXIT)
policy->governor->initialized--;
+ } else {
+ /* Restore original values */
+ mutex_lock(&cpufreq_governor_lock);
+ if (event == CPUFREQ_GOV_STOP)
+ policy->governor_enabled = true;
+ else if (event == CPUFREQ_GOV_START)
+ policy->governor_enabled = false;
+ mutex_unlock(&cpufreq_governor_lock);
}
/* we keep one module reference alive for
return ret;
}
-
int cpufreq_register_governor(struct cpufreq_governor *governor)
{
int err;
}
EXPORT_SYMBOL_GPL(cpufreq_register_governor);
-
void cpufreq_unregister_governor(struct cpufreq_governor *governor)
{
#ifdef CONFIG_HOTPLUG_CPU
EXPORT_SYMBOL_GPL(cpufreq_unregister_governor);
-
/*********************************************************************
* POLICY INTERFACE *
*********************************************************************/
}
EXPORT_SYMBOL(cpufreq_get_policy);
-
/*
* data : current policy.
* policy : policy to be set.
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
CPUFREQ_INCOMPATIBLE, policy);
- /* verify the cpu speed can be set within this limit,
- which might be different to the first one */
+ /*
+ * verify the cpu speed can be set within this limit, which might be
+ * different to the first one
+ */
ret = cpufreq_driver->verify(policy);
if (ret)
goto error_out;
/* end old governor */
if (data->governor) {
__cpufreq_governor(data, CPUFREQ_GOV_STOP);
+ unlock_policy_rwsem_write(policy->cpu);
__cpufreq_governor(data,
CPUFREQ_GOV_POLICY_EXIT);
+ lock_policy_rwsem_write(policy->cpu);
}
/* start new governor */
data->governor = policy->governor;
if (!__cpufreq_governor(data, CPUFREQ_GOV_POLICY_INIT)) {
- if (!__cpufreq_governor(data, CPUFREQ_GOV_START))
+ if (!__cpufreq_governor(data, CPUFREQ_GOV_START)) {
failed = 0;
- else
+ } else {
+ unlock_policy_rwsem_write(policy->cpu);
__cpufreq_governor(data,
CPUFREQ_GOV_POLICY_EXIT);
+ lock_policy_rwsem_write(policy->cpu);
+ }
}
if (failed) {
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 */
+ /*
+ * 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) {
}
static struct notifier_block __refdata cpufreq_cpu_notifier = {
- .notifier_call = cpufreq_cpu_callback,
+ .notifier_call = cpufreq_cpu_callback,
};
/*********************************************************************
* @driver_data: A struct cpufreq_driver containing the values#
* submitted by the CPU Frequency driver.
*
- * Registers a CPU Frequency driver to this core code. This code
+ * Registers a CPU Frequency driver to this core code. This code
* returns zero on success, -EBUSY when another driver got here first
* (and isn't unregistered in the meantime).
*
}
EXPORT_SYMBOL_GPL(cpufreq_register_driver);
-
/**
* cpufreq_unregister_driver - unregister the current CPUFreq driver
*
- * Unregister the current CPUFreq driver. Only call this if you have
+ * Unregister the current CPUFreq driver. Only call this if you have
* the right to do so, i.e. if you have succeeded in initialising before!
* Returns zero if successful, and -EINVAL if the cpufreq_driver is
* currently not initialised.
init_rwsem(&per_cpu(cpu_policy_rwsem, cpu));
}
- cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj);
+ cpufreq_global_kobject = kobject_create();
BUG_ON(!cpufreq_global_kobject);
register_syscore_ops(&cpufreq_syscore_ops);
projects / linux-imx.git / blobdiff