projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 75722d39 BH |
1 | #include <linux/config.h> |
| 2 | #include <linux/types.h> | |
| 3 | #include <linux/errno.h> | |
| 4 | #include <linux/kernel.h> | |
| 5 | #include <linux/delay.h> | |
| 6 | #include <linux/slab.h> | |
| 7 | #include <linux/init.h> | |
| 8 | #include <linux/wait.h> | |
| 9 | #include <linux/cpufreq.h> | |
| 10 | ||
| b55fafc5 BH |
11 | #include <asm/prom.h> |
| 12 | ||
| 75722d39 BH |
13 | #include "windfarm.h" |
| 14 | ||
| 15 | #define VERSION "0.3" | |
| 16 | ||
| 17 | static int clamped; | |
| 18 | static struct wf_control *clamp_control; | |
| 19 | ||
| 20 | static int clamp_notifier_call(struct notifier_block *self, | |
| 21 | unsigned long event, void *data) | |
| 22 | { | |
| 23 | struct cpufreq_policy *p = data; | |
| 24 | unsigned long max_freq; | |
| 25 | ||
| 26 | if (event != CPUFREQ_ADJUST) | |
| 27 | return 0; | |
| 28 | ||
| 29 | max_freq = clamped ? (p->cpuinfo.min_freq) : (p->cpuinfo.max_freq); | |
| 30 | cpufreq_verify_within_limits(p, 0, max_freq); | |
| 31 | ||
| 32 | return 0; | |
| 33 | } | |
| 34 | ||
| 35 | static struct notifier_block clamp_notifier = { | |
| 36 | .notifier_call = clamp_notifier_call, | |
| 37 | }; | |
| 38 | ||
| 39 | static int clamp_set(struct wf_control *ct, s32 value) | |
| 40 | { | |
| 41 | if (value) | |
| 42 | printk(KERN_INFO "windfarm: Clamping CPU frequency to " | |
| 43 | "minimum !\n"); | |
| 44 | else | |
| 45 | printk(KERN_INFO "windfarm: CPU frequency unclamped !\n"); | |
| 46 | clamped = value; | |
| 47 | cpufreq_update_policy(0); | |
| 48 | return 0; | |
| 49 | } | |
| 50 | ||
| 51 | static int clamp_get(struct wf_control *ct, s32 *value) | |
| 52 | { | |
| 53 | *value = clamped; | |
| 54 | return 0; | |
| 55 | } | |
| 56 | ||
| 57 | static s32 clamp_min(struct wf_control *ct) | |
| 58 | { | |
| 59 | return 0; | |
| 60 | } | |
| 61 | ||
| 62 | static s32 clamp_max(struct wf_control *ct) | |
| 63 | { | |
| 64 | return 1; | |
| 65 | } | |
| 66 | ||
| 67 | static struct wf_control_ops clamp_ops = { | |
| 68 | .set_value = clamp_set, | |
| 69 | .get_value = clamp_get, | |
| 70 | .get_min = clamp_min, | |
| 71 | .get_max = clamp_max, | |
| 72 | .owner = THIS_MODULE, | |
| 73 | }; | |
| 74 | ||
| 75 | static int __init wf_cpufreq_clamp_init(void) | |
| 76 | { | |
| 77 | struct wf_control *clamp; | |
| 78 | ||
| b55fafc5 BH |
79 | /* Don't register on old machines that use therm_pm72 for now */ |
| 80 | if (machine_is_compatible("PowerMac7,2") || | |
| 81 | machine_is_compatible("PowerMac7,3") || | |
| 82 | machine_is_compatible("RackMac3,1")) | |
| 83 | return -ENODEV; | |
| 84 | ||
| 75722d39 BH |
85 | clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL); |
| 86 | if (clamp == NULL) | |
| 87 | return -ENOMEM; | |
| 88 | cpufreq_register_notifier(&clamp_notifier, CPUFREQ_POLICY_NOTIFIER); | |
| 89 | clamp->ops = &clamp_ops; | |
| 90 | clamp->name = "cpufreq-clamp"; | |
| 91 | if (wf_register_control(clamp)) | |
| 92 | goto fail; | |
| 93 | clamp_control = clamp; | |
| 94 | return 0; | |
| 95 | fail: | |
| 96 | kfree(clamp); | |
| 97 | return -ENODEV; | |
| 98 | } | |
| 99 | ||
| 100 | static void __exit wf_cpufreq_clamp_exit(void) | |
| 101 | { | |
| 102 | if (clamp_control) | |
| 103 | wf_unregister_control(clamp_control); | |
| 104 | } | |
| 105 | ||
| 106 | ||
| 107 | module_init(wf_cpufreq_clamp_init); | |
| 108 | module_exit(wf_cpufreq_clamp_exit); | |
| 109 | ||
| 110 | MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); | |
| 111 | MODULE_DESCRIPTION("CPU frequency clamp for PowerMacs thermal control"); | |
| 112 | MODULE_LICENSE("GPL"); | |
| 113 |