1ad35f6e28
Make wf_control_ops const as they are only stored in the ops field of a wf_control structure, which is const. Make wf_pid_param const as they are only used during a copy operation. Done using Coccinelle. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
107 lines
2.1 KiB
C
107 lines
2.1 KiB
C
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/init.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/cpufreq.h>
|
|
|
|
#include <asm/prom.h>
|
|
|
|
#include "windfarm.h"
|
|
|
|
#define VERSION "0.3"
|
|
|
|
static int clamped;
|
|
static struct wf_control *clamp_control;
|
|
|
|
static int clamp_notifier_call(struct notifier_block *self,
|
|
unsigned long event, void *data)
|
|
{
|
|
struct cpufreq_policy *p = data;
|
|
unsigned long max_freq;
|
|
|
|
if (event != CPUFREQ_ADJUST)
|
|
return 0;
|
|
|
|
max_freq = clamped ? (p->cpuinfo.min_freq) : (p->cpuinfo.max_freq);
|
|
cpufreq_verify_within_limits(p, 0, max_freq);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct notifier_block clamp_notifier = {
|
|
.notifier_call = clamp_notifier_call,
|
|
};
|
|
|
|
static int clamp_set(struct wf_control *ct, s32 value)
|
|
{
|
|
if (value)
|
|
printk(KERN_INFO "windfarm: Clamping CPU frequency to "
|
|
"minimum !\n");
|
|
else
|
|
printk(KERN_INFO "windfarm: CPU frequency unclamped !\n");
|
|
clamped = value;
|
|
cpufreq_update_policy(0);
|
|
return 0;
|
|
}
|
|
|
|
static int clamp_get(struct wf_control *ct, s32 *value)
|
|
{
|
|
*value = clamped;
|
|
return 0;
|
|
}
|
|
|
|
static s32 clamp_min(struct wf_control *ct)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static s32 clamp_max(struct wf_control *ct)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static const struct wf_control_ops clamp_ops = {
|
|
.set_value = clamp_set,
|
|
.get_value = clamp_get,
|
|
.get_min = clamp_min,
|
|
.get_max = clamp_max,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static int __init wf_cpufreq_clamp_init(void)
|
|
{
|
|
struct wf_control *clamp;
|
|
|
|
clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL);
|
|
if (clamp == NULL)
|
|
return -ENOMEM;
|
|
cpufreq_register_notifier(&clamp_notifier, CPUFREQ_POLICY_NOTIFIER);
|
|
clamp->ops = &clamp_ops;
|
|
clamp->name = "cpufreq-clamp";
|
|
if (wf_register_control(clamp))
|
|
goto fail;
|
|
clamp_control = clamp;
|
|
return 0;
|
|
fail:
|
|
kfree(clamp);
|
|
return -ENODEV;
|
|
}
|
|
|
|
static void __exit wf_cpufreq_clamp_exit(void)
|
|
{
|
|
if (clamp_control)
|
|
wf_unregister_control(clamp_control);
|
|
}
|
|
|
|
|
|
module_init(wf_cpufreq_clamp_init);
|
|
module_exit(wf_cpufreq_clamp_exit);
|
|
|
|
MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
|
|
MODULE_DESCRIPTION("CPU frequency clamp for PowerMacs thermal control");
|
|
MODULE_LICENSE("GPL");
|
|
|