diff options
Diffstat (limited to 'arch/arm/mach-tegra/cpuidle.c')
-rw-r--r-- | arch/arm/mach-tegra/cpuidle.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/cpuidle.c b/arch/arm/mach-tegra/cpuidle.c new file mode 100644 index 000000000000..d83a8c0296f5 --- /dev/null +++ b/arch/arm/mach-tegra/cpuidle.c | |||
@@ -0,0 +1,107 @@ | |||
1 | /* | ||
2 | * arch/arm/mach-tegra/cpuidle.c | ||
3 | * | ||
4 | * CPU idle driver for Tegra CPUs | ||
5 | * | ||
6 | * Copyright (c) 2010-2012, NVIDIA Corporation. | ||
7 | * Copyright (c) 2011 Google, Inc. | ||
8 | * Author: Colin Cross <ccross@android.com> | ||
9 | * Gary King <gking@nvidia.com> | ||
10 | * | ||
11 | * Rework for 3.3 by Peter De Schrijver <pdeschrijver@nvidia.com> | ||
12 | * | ||
13 | * This program is free software; you can redistribute it and/or modify | ||
14 | * it under the terms of the GNU General Public License as published by | ||
15 | * the Free Software Foundation; either version 2 of the License, or | ||
16 | * (at your option) any later version. | ||
17 | * | ||
18 | * This program is distributed in the hope that it will be useful, but WITHOUT | ||
19 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
20 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | ||
21 | * more details. | ||
22 | */ | ||
23 | |||
24 | #include <linux/kernel.h> | ||
25 | #include <linux/module.h> | ||
26 | #include <linux/cpu.h> | ||
27 | #include <linux/cpuidle.h> | ||
28 | #include <linux/hrtimer.h> | ||
29 | |||
30 | #include <mach/iomap.h> | ||
31 | |||
32 | extern void tegra_cpu_wfi(void); | ||
33 | |||
34 | static int tegra_idle_enter_lp3(struct cpuidle_device *dev, | ||
35 | struct cpuidle_driver *drv, int index); | ||
36 | |||
37 | struct cpuidle_driver tegra_idle_driver = { | ||
38 | .name = "tegra_idle", | ||
39 | .owner = THIS_MODULE, | ||
40 | .state_count = 1, | ||
41 | .states = { | ||
42 | [0] = { | ||
43 | .enter = tegra_idle_enter_lp3, | ||
44 | .exit_latency = 10, | ||
45 | .target_residency = 10, | ||
46 | .power_usage = 600, | ||
47 | .flags = CPUIDLE_FLAG_TIME_VALID, | ||
48 | .name = "LP3", | ||
49 | .desc = "CPU flow-controlled", | ||
50 | }, | ||
51 | }, | ||
52 | }; | ||
53 | |||
54 | static DEFINE_PER_CPU(struct cpuidle_device, tegra_idle_device); | ||
55 | |||
56 | static int tegra_idle_enter_lp3(struct cpuidle_device *dev, | ||
57 | struct cpuidle_driver *drv, int index) | ||
58 | { | ||
59 | ktime_t enter, exit; | ||
60 | s64 us; | ||
61 | |||
62 | local_irq_disable(); | ||
63 | local_fiq_disable(); | ||
64 | |||
65 | enter = ktime_get(); | ||
66 | |||
67 | tegra_cpu_wfi(); | ||
68 | |||
69 | exit = ktime_sub(ktime_get(), enter); | ||
70 | us = ktime_to_us(exit); | ||
71 | |||
72 | local_fiq_enable(); | ||
73 | local_irq_enable(); | ||
74 | |||
75 | dev->last_residency = us; | ||
76 | |||
77 | return index; | ||
78 | } | ||
79 | |||
80 | static int __init tegra_cpuidle_init(void) | ||
81 | { | ||
82 | int ret; | ||
83 | unsigned int cpu; | ||
84 | struct cpuidle_device *dev; | ||
85 | struct cpuidle_driver *drv = &tegra_idle_driver; | ||
86 | |||
87 | ret = cpuidle_register_driver(&tegra_idle_driver); | ||
88 | if (ret) { | ||
89 | pr_err("CPUidle driver registration failed\n"); | ||
90 | return ret; | ||
91 | } | ||
92 | |||
93 | for_each_possible_cpu(cpu) { | ||
94 | dev = &per_cpu(tegra_idle_device, cpu); | ||
95 | dev->cpu = cpu; | ||
96 | |||
97 | dev->state_count = drv->state_count; | ||
98 | ret = cpuidle_register_device(dev); | ||
99 | if (ret) { | ||
100 | pr_err("CPU%u: CPUidle device registration failed\n", | ||
101 | cpu); | ||
102 | return ret; | ||
103 | } | ||
104 | } | ||
105 | return 0; | ||
106 | } | ||
107 | device_initcall(tegra_cpuidle_init); | ||