Linux-2.6.12-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!
This commit is contained in:
Linus Torvalds
207
drivers/cpufreq/cpufreq_userspace.c
Normal file
207
drivers/cpufreq/cpufreq_userspace.c
Normal file
@@ -0,0 +1,207 @@
|
||||
/*
|
||||
* linux/drivers/cpufreq/cpufreq_userspace.c
|
||||
*
|
||||
* Copyright (C) 2001 Russell King
|
||||
* (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
|
||||
*
|
||||
* 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/config.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/smp.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/interrupt.h>
|
||||
#include <linux/cpufreq.h>
|
||||
#include <linux/types.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/sysfs.h>
|
||||
|
||||
#include <asm/uaccess.h>
|
||||
|
||||
|
||||
/**
|
||||
* A few values needed by the userspace governor
|
||||
*/
|
||||
static unsigned int cpu_max_freq[NR_CPUS];
|
||||
static unsigned int cpu_min_freq[NR_CPUS];
|
||||
static unsigned int cpu_cur_freq[NR_CPUS]; /* current CPU freq */
|
||||
static unsigned int cpu_set_freq[NR_CPUS]; /* CPU freq desired by userspace */
|
||||
static unsigned int cpu_is_managed[NR_CPUS];
|
||||
static struct cpufreq_policy current_policy[NR_CPUS];
|
||||
|
||||
static DECLARE_MUTEX (userspace_sem);
|
||||
|
||||
#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_GOVERNOR, "userspace", msg)
|
||||
|
||||
/* keep track of frequency transitions */
|
||||
static int
|
||||
userspace_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
|
||||
void *data)
|
||||
{
|
||||
struct cpufreq_freqs *freq = data;
|
||||
|
||||
dprintk("saving cpu_cur_freq of cpu %u to be %u kHz\n", freq->cpu, freq->new);
|
||||
cpu_cur_freq[freq->cpu] = freq->new;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct notifier_block userspace_cpufreq_notifier_block = {
|
||||
.notifier_call = userspace_cpufreq_notifier
|
||||
};
|
||||
|
||||
|
||||
/**
|
||||
* cpufreq_set - set the CPU frequency
|
||||
* @freq: target frequency in kHz
|
||||
* @cpu: CPU for which the frequency is to be set
|
||||
*
|
||||
* Sets the CPU frequency to freq.
|
||||
*/
|
||||
static int cpufreq_set(unsigned int freq, unsigned int cpu)
|
||||
{
|
||||
int ret = -EINVAL;
|
||||
|
||||
dprintk("cpufreq_set for cpu %u, freq %u kHz\n", cpu, freq);
|
||||
|
||||
down(&userspace_sem);
|
||||
if (!cpu_is_managed[cpu])
|
||||
goto err;
|
||||
|
||||
cpu_set_freq[cpu] = freq;
|
||||
|
||||
if (freq < cpu_min_freq[cpu])
|
||||
freq = cpu_min_freq[cpu];
|
||||
if (freq > cpu_max_freq[cpu])
|
||||
freq = cpu_max_freq[cpu];
|
||||
|
||||
/*
|
||||
* We're safe from concurrent calls to ->target() here
|
||||
* as we hold the userspace_sem lock. If we were calling
|
||||
* cpufreq_driver_target, a deadlock situation might occur:
|
||||
* A: cpufreq_set (lock userspace_sem) -> cpufreq_driver_target(lock policy->lock)
|
||||
* B: cpufreq_set_policy(lock policy->lock) -> __cpufreq_governor -> cpufreq_governor_userspace (lock userspace_sem)
|
||||
*/
|
||||
ret = __cpufreq_driver_target(¤t_policy[cpu], freq,
|
||||
CPUFREQ_RELATION_L);
|
||||
|
||||
err:
|
||||
up(&userspace_sem);
|
||||
return ret;
|
||||
}
|
||||
|
||||
|
||||
/************************** sysfs interface ************************/
|
||||
static ssize_t show_speed (struct cpufreq_policy *policy, char *buf)
|
||||
{
|
||||
return sprintf (buf, "%u\n", cpu_cur_freq[policy->cpu]);
|
||||
}
|
||||
|
||||
static ssize_t
|
||||
store_speed (struct cpufreq_policy *policy, const char *buf, size_t count)
|
||||
{
|
||||
unsigned int freq = 0;
|
||||
unsigned int ret;
|
||||
|
||||
ret = sscanf (buf, "%u", &freq);
|
||||
if (ret != 1)
|
||||
return -EINVAL;
|
||||
|
||||
cpufreq_set(freq, policy->cpu);
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
static struct freq_attr freq_attr_scaling_setspeed =
|
||||
{
|
||||
.attr = { .name = "scaling_setspeed", .mode = 0644, .owner = THIS_MODULE },
|
||||
.show = show_speed,
|
||||
.store = store_speed,
|
||||
};
|
||||
|
||||
static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
|
||||
unsigned int event)
|
||||
{
|
||||
unsigned int cpu = policy->cpu;
|
||||
switch (event) {
|
||||
case CPUFREQ_GOV_START:
|
||||
if (!cpu_online(cpu))
|
||||
return -EINVAL;
|
||||
BUG_ON(!policy->cur);
|
||||
down(&userspace_sem);
|
||||
cpu_is_managed[cpu] = 1;
|
||||
cpu_min_freq[cpu] = policy->min;
|
||||
cpu_max_freq[cpu] = policy->max;
|
||||
cpu_cur_freq[cpu] = policy->cur;
|
||||
cpu_set_freq[cpu] = policy->cur;
|
||||
sysfs_create_file (&policy->kobj, &freq_attr_scaling_setspeed.attr);
|
||||
memcpy (¤t_policy[cpu], policy, sizeof(struct cpufreq_policy));
|
||||
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]);
|
||||
up(&userspace_sem);
|
||||
break;
|
||||
case CPUFREQ_GOV_STOP:
|
||||
down(&userspace_sem);
|
||||
cpu_is_managed[cpu] = 0;
|
||||
cpu_min_freq[cpu] = 0;
|
||||
cpu_max_freq[cpu] = 0;
|
||||
cpu_set_freq[cpu] = 0;
|
||||
sysfs_remove_file (&policy->kobj, &freq_attr_scaling_setspeed.attr);
|
||||
dprintk("managing cpu %u stopped\n", cpu);
|
||||
up(&userspace_sem);
|
||||
break;
|
||||
case CPUFREQ_GOV_LIMITS:
|
||||
down(&userspace_sem);
|
||||
cpu_min_freq[cpu] = policy->min;
|
||||
cpu_max_freq[cpu] = policy->max;
|
||||
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]);
|
||||
if (policy->max < cpu_set_freq[cpu]) {
|
||||
__cpufreq_driver_target(¤t_policy[cpu], policy->max,
|
||||
CPUFREQ_RELATION_H);
|
||||
} else if (policy->min > cpu_set_freq[cpu]) {
|
||||
__cpufreq_driver_target(¤t_policy[cpu], policy->min,
|
||||
CPUFREQ_RELATION_L);
|
||||
} else {
|
||||
__cpufreq_driver_target(¤t_policy[cpu], cpu_set_freq[cpu],
|
||||
CPUFREQ_RELATION_L);
|
||||
}
|
||||
memcpy (¤t_policy[cpu], policy, sizeof(struct cpufreq_policy));
|
||||
up(&userspace_sem);
|
||||
break;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
struct cpufreq_governor cpufreq_gov_userspace = {
|
||||
.name = "userspace",
|
||||
.governor = cpufreq_governor_userspace,
|
||||
.owner = THIS_MODULE,
|
||||
};
|
||||
EXPORT_SYMBOL(cpufreq_gov_userspace);
|
||||
|
||||
static int __init cpufreq_gov_userspace_init(void)
|
||||
{
|
||||
cpufreq_register_notifier(&userspace_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
|
||||
return cpufreq_register_governor(&cpufreq_gov_userspace);
|
||||
}
|
||||
|
||||
|
||||
static void __exit cpufreq_gov_userspace_exit(void)
|
||||
{
|
||||
cpufreq_unregister_governor(&cpufreq_gov_userspace);
|
||||
cpufreq_unregister_notifier(&userspace_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
|
||||
}
|
||||
|
||||
|
||||
MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>, Russell King <rmk@arm.linux.org.uk>");
|
||||
MODULE_DESCRIPTION ("CPUfreq policy governor 'userspace'");
|
||||
MODULE_LICENSE ("GPL");
|
||||
|
||||
fs_initcall(cpufreq_gov_userspace_init);
|
||||
module_exit(cpufreq_gov_userspace_exit);
|
||||
Reference in New Issue
Block a user