1 /*
2 * CPUIdle support code for SH-Mobile ARM
3 *
4 * Copyright (C) 2011 Magnus Damm
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11 #include <linux/pm.h>
12 #include <linux/cpuidle.h>
13 #include <linux/suspend.h>
14 #include <linux/module.h>
15 #include <linux/err.h>
16 #include <asm/system.h>
17 #include <asm/io.h>
18
shmobile_enter_wfi(void)19 static void shmobile_enter_wfi(void)
20 {
21 cpu_do_idle();
22 }
23
24 void (*shmobile_cpuidle_modes[CPUIDLE_STATE_MAX])(void) = {
25 shmobile_enter_wfi, /* regular sleep mode */
26 };
27
shmobile_cpuidle_enter(struct cpuidle_device * dev,struct cpuidle_driver * drv,int index)28 static int shmobile_cpuidle_enter(struct cpuidle_device *dev,
29 struct cpuidle_driver *drv,
30 int index)
31 {
32 ktime_t before, after;
33
34 before = ktime_get();
35
36 local_irq_disable();
37 local_fiq_disable();
38
39 shmobile_cpuidle_modes[index]();
40
41 local_irq_enable();
42 local_fiq_enable();
43
44 after = ktime_get();
45 dev->last_residency = ktime_to_ns(ktime_sub(after, before)) >> 10;
46
47 return index;
48 }
49
50 static struct cpuidle_device shmobile_cpuidle_dev;
51 static struct cpuidle_driver shmobile_cpuidle_driver = {
52 .name = "shmobile_cpuidle",
53 .owner = THIS_MODULE,
54 .states[0] = {
55 .name = "C1",
56 .desc = "WFI",
57 .exit_latency = 1,
58 .target_residency = 1 * 2,
59 .flags = CPUIDLE_FLAG_TIME_VALID,
60 },
61 .safe_state_index = 0, /* C1 */
62 .state_count = 1,
63 };
64
65 void (*shmobile_cpuidle_setup)(struct cpuidle_driver *drv);
66
shmobile_cpuidle_init(void)67 static int shmobile_cpuidle_init(void)
68 {
69 struct cpuidle_device *dev = &shmobile_cpuidle_dev;
70 struct cpuidle_driver *drv = &shmobile_cpuidle_driver;
71 int i;
72
73 for (i = 0; i < CPUIDLE_STATE_MAX; i++)
74 drv->states[i].enter = shmobile_cpuidle_enter;
75
76 if (shmobile_cpuidle_setup)
77 shmobile_cpuidle_setup(drv);
78
79 cpuidle_register_driver(drv);
80
81 dev->state_count = drv->state_count;
82 cpuidle_register_device(dev);
83
84 return 0;
85 }
86 late_initcall(shmobile_cpuidle_init);
87