1#include <linux/types.h>
  2#include <linux/errno.h>
  3#include <linux/kernel.h>
  4#include <linux/delay.h>
  5#include <linux/slab.h>
  6#include <linux/init.h>
  7#include <linux/wait.h>
  8#include <linux/cpufreq.h>
  9
 10#include <asm/prom.h>
 11
 12#include "windfarm.h"
 13
 14#define VERSION "0.3"
 15
 16static int clamped;
 17static struct wf_control *clamp_control;
 18
 19static int clamp_notifier_call(struct notifier_block *self,
 20			       unsigned long event, void *data)
 21{
 22	struct cpufreq_policy *p = data;
 23	unsigned long max_freq;
 24
 25	if (event != CPUFREQ_ADJUST)
 26		return 0;
 27
 28	max_freq = clamped ? (p->cpuinfo.min_freq) : (p->cpuinfo.max_freq);
 29	cpufreq_verify_within_limits(p, 0, max_freq);
 30
 31	return 0;
 32}
 33
 34static struct notifier_block clamp_notifier = {
 35	.notifier_call = clamp_notifier_call,
 36};
 37
 38static int clamp_set(struct wf_control *ct, s32 value)
 39{
 40	if (value)
 41		printk(KERN_INFO "windfarm: Clamping CPU frequency to "
 42		       "minimum !\n");
 43	else
 44		printk(KERN_INFO "windfarm: CPU frequency unclamped !\n");
 45	clamped = value;
 46	cpufreq_update_policy(0);
 47	return 0;
 48}
 49
 50static int clamp_get(struct wf_control *ct, s32 *value)
 51{
 52	*value = clamped;
 53	return 0;
 54}
 55
 56static s32 clamp_min(struct wf_control *ct)
 57{
 58	return 0;
 59}
 60
 61static s32 clamp_max(struct wf_control *ct)
 62{
 63	return 1;
 64}
 65
 66static struct wf_control_ops clamp_ops = {
 67	.set_value	= clamp_set,
 68	.get_value	= clamp_get,
 69	.get_min	= clamp_min,
 70	.get_max	= clamp_max,
 71	.owner		= THIS_MODULE,
 72};
 73
 74static int __init wf_cpufreq_clamp_init(void)
 75{
 76	struct wf_control *clamp;
 77
 78	/* Don't register on old machines that use therm_pm72 for now */
 79	if (of_machine_is_compatible("PowerMac7,2") ||
 80	    of_machine_is_compatible("PowerMac7,3") ||
 81	    of_machine_is_compatible("RackMac3,1"))
 82		return -ENODEV;
 83
 84	clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL);
 85	if (clamp == NULL)
 86		return -ENOMEM;
 87	cpufreq_register_notifier(&clamp_notifier, CPUFREQ_POLICY_NOTIFIER);
 88	clamp->ops = &clamp_ops;
 89	clamp->name = "cpufreq-clamp";
 90	if (wf_register_control(clamp))
 91		goto fail;
 92	clamp_control = clamp;
 93	return 0;
 94 fail:
 95	kfree(clamp);
 96	return -ENODEV;
 97}
 98
 99static void __exit wf_cpufreq_clamp_exit(void)
100{
101	if (clamp_control)
102		wf_unregister_control(clamp_control);
103}
104
105
106module_init(wf_cpufreq_clamp_init);
107module_exit(wf_cpufreq_clamp_exit);
108
109MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
110MODULE_DESCRIPTION("CPU frequency clamp for PowerMacs thermal control");
111MODULE_LICENSE("GPL");
112

  1#include <linux/types.h>
  2#include <linux/errno.h>
  3#include <linux/kernel.h>
  4#include <linux/delay.h>
  5#include <linux/slab.h>
  6#include <linux/init.h>
  7#include <linux/wait.h>
  8#include <linux/cpufreq.h>
  9
 10#include <asm/prom.h>
 11
 12#include "windfarm.h"
 13
 14#define VERSION "0.3"
 15
 16static int clamped;
 17static struct wf_control *clamp_control;
 18
 19static int clamp_notifier_call(struct notifier_block *self,
 20			       unsigned long event, void *data)
 21{
 22	struct cpufreq_policy *p = data;
 23	unsigned long max_freq;
 24
 25	if (event != CPUFREQ_ADJUST)
 26		return 0;
 27
 28	max_freq = clamped ? (p->cpuinfo.min_freq) : (p->cpuinfo.max_freq);
 29	cpufreq_verify_within_limits(p, 0, max_freq);
 30
 31	return 0;
 32}
 33
 34static struct notifier_block clamp_notifier = {
 35	.notifier_call = clamp_notifier_call,
 36};
 37
 38static int clamp_set(struct wf_control *ct, s32 value)
 39{
 40	if (value)
 41		printk(KERN_INFO "windfarm: Clamping CPU frequency to "
 42		       "minimum !\n");
 43	else
 44		printk(KERN_INFO "windfarm: CPU frequency unclamped !\n");
 45	clamped = value;
 46	cpufreq_update_policy(0);
 47	return 0;
 48}
 49
 50static int clamp_get(struct wf_control *ct, s32 *value)
 51{
 52	*value = clamped;
 53	return 0;
 54}
 55
 56static s32 clamp_min(struct wf_control *ct)
 57{
 58	return 0;
 59}
 60
 61static s32 clamp_max(struct wf_control *ct)
 62{
 63	return 1;
 64}
 65
 66static const struct wf_control_ops clamp_ops = {
 67	.set_value	= clamp_set,
 68	.get_value	= clamp_get,
 69	.get_min	= clamp_min,
 70	.get_max	= clamp_max,
 71	.owner		= THIS_MODULE,
 72};
 73
 74static int __init wf_cpufreq_clamp_init(void)
 75{
 76	struct wf_control *clamp;
 
 
 
 
 
 
 77
 78	clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL);
 79	if (clamp == NULL)
 80		return -ENOMEM;
 81	cpufreq_register_notifier(&clamp_notifier, CPUFREQ_POLICY_NOTIFIER);
 82	clamp->ops = &clamp_ops;
 83	clamp->name = "cpufreq-clamp";
 84	if (wf_register_control(clamp))
 85		goto fail;
 86	clamp_control = clamp;
 87	return 0;
 88 fail:
 89	kfree(clamp);
 90	return -ENODEV;
 91}
 92
 93static void __exit wf_cpufreq_clamp_exit(void)
 94{
 95	if (clamp_control)
 96		wf_unregister_control(clamp_control);
 97}
 98
 99
100module_init(wf_cpufreq_clamp_init);
101module_exit(wf_cpufreq_clamp_exit);
102
103MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
104MODULE_DESCRIPTION("CPU frequency clamp for PowerMacs thermal control");
105MODULE_LICENSE("GPL");
106