projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 3d739985 JL |
1 | /* linux/arch/arm/mach-exynos4/cpuidle.c |
| 2 | * | |
| 3 | * Copyright (c) 2011 Samsung Electronics Co., Ltd. | |
| 4 | * http://www.samsung.com | |
| 5 | * | |
| 6 | * This program is free software; you can redistribute it and/or modify | |
| 7 | * it under the terms of the GNU General Public License version 2 as | |
| 8 | * published by the Free Software Foundation. | |
| 9 | */ | |
| 10 | ||
| 11 | #include <linux/kernel.h> | |
| 12 | #include <linux/init.h> | |
| 13 | #include <linux/cpuidle.h> | |
| 14 | #include <linux/io.h> | |
| 15 | ||
| 16 | #include <asm/proc-fns.h> | |
| 17 | ||
| 18 | static int exynos4_enter_idle(struct cpuidle_device *dev, | |
| 19 | struct cpuidle_state *state); | |
| 20 | ||
| 21 | static struct cpuidle_state exynos4_cpuidle_set[] = { | |
| 22 | [0] = { | |
| 23 | .enter = exynos4_enter_idle, | |
| 24 | .exit_latency = 1, | |
| 25 | .target_residency = 100000, | |
| 26 | .flags = CPUIDLE_FLAG_TIME_VALID, | |
| 27 | .name = "IDLE", | |
| 28 | .desc = "ARM clock gating(WFI)", | |
| 29 | }, | |
| 30 | }; | |
| 31 | ||
| 32 | static DEFINE_PER_CPU(struct cpuidle_device, exynos4_cpuidle_device); | |
| 33 | ||
| 34 | static struct cpuidle_driver exynos4_idle_driver = { | |
| 35 | .name = "exynos4_idle", | |
| 36 | .owner = THIS_MODULE, | |
| 37 | }; | |
| 38 | ||
| 39 | static int exynos4_enter_idle(struct cpuidle_device *dev, | |
| 40 | struct cpuidle_state *state) | |
| 41 | { | |
| 42 | struct timeval before, after; | |
| 43 | int idle_time; | |
| 44 | ||
| 45 | local_irq_disable(); | |
| 46 | do_gettimeofday(&before); | |
| 47 | ||
| 48 | cpu_do_idle(); | |
| 49 | ||
| 50 | do_gettimeofday(&after); | |
| 51 | local_irq_enable(); | |
| 52 | idle_time = (after.tv_sec - before.tv_sec) * USEC_PER_SEC + | |
| 53 | (after.tv_usec - before.tv_usec); | |
| 54 | ||
| 55 | return idle_time; | |
| 56 | } | |
| 57 | ||
| 58 | static int __init exynos4_init_cpuidle(void) | |
| 59 | { | |
| 60 | int i, max_cpuidle_state, cpu_id; | |
| 61 | struct cpuidle_device *device; | |
| 62 | ||
| 63 | cpuidle_register_driver(&exynos4_idle_driver); | |
| 64 | ||
| 65 | for_each_cpu(cpu_id, cpu_online_mask) { | |
| 66 | device = &per_cpu(exynos4_cpuidle_device, cpu_id); | |
| 67 | device->cpu = cpu_id; | |
| 68 | ||
| 69 | device->state_count = (sizeof(exynos4_cpuidle_set) / | |
| 70 | sizeof(struct cpuidle_state)); | |
| 71 | ||
| 72 | max_cpuidle_state = device->state_count; | |
| 73 | ||
| 74 | for (i = 0; i < max_cpuidle_state; i++) { | |
| 75 | memcpy(&device->states[i], &exynos4_cpuidle_set[i], | |
| 76 | sizeof(struct cpuidle_state)); | |
| 77 | } | |
| 78 | ||
| 79 | if (cpuidle_register_device(device)) { | |
| 80 | printk(KERN_ERR "CPUidle register device failed\n,"); | |
| 81 | return -EIO; | |
| 82 | } | |
| 83 | } | |
| 84 | return 0; | |
| 85 | } | |
| 86 | device_initcall(exynos4_init_cpuidle); |