blob: cc48d7fa3358d023ca0e1de9fecd2484c2844c96 [file] [log] [blame]
Joseph Lo0b25e252012-10-31 17:41:15 +08001/*
2 * CPU idle driver for Tegra CPUs
3 *
4 * Copyright (c) 2010-2012, NVIDIA Corporation.
5 * Copyright (c) 2011 Google, Inc.
6 * Author: Colin Cross <ccross@android.com>
7 * Gary King <gking@nvidia.com>
8 *
9 * Rework for 3.3 by Peter De Schrijver <pdeschrijver@nvidia.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful, but WITHOUT
17 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
19 * more details.
20 */
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/cpuidle.h>
Joseph Lod457ef352012-10-31 17:41:17 +080025#include <linux/cpu_pm.h>
26#include <linux/clockchips.h>
Joseph Lo0b25e252012-10-31 17:41:15 +080027
28#include <asm/cpuidle.h>
Joseph Lod457ef352012-10-31 17:41:17 +080029#include <asm/proc-fns.h>
30#include <asm/suspend.h>
31#include <asm/smp_plat.h>
32
33#include "pm.h"
34#include "sleep.h"
35
36#ifdef CONFIG_PM_SLEEP
37static int tegra30_idle_lp2(struct cpuidle_device *dev,
38 struct cpuidle_driver *drv,
39 int index);
40#endif
Joseph Lo0b25e252012-10-31 17:41:15 +080041
42static struct cpuidle_driver tegra_idle_driver = {
43 .name = "tegra_idle",
44 .owner = THIS_MODULE,
45 .en_core_tk_irqen = 1,
Joseph Lod457ef352012-10-31 17:41:17 +080046#ifdef CONFIG_PM_SLEEP
47 .state_count = 2,
48#else
Joseph Lo0b25e252012-10-31 17:41:15 +080049 .state_count = 1,
Joseph Lod457ef352012-10-31 17:41:17 +080050#endif
Joseph Lo0b25e252012-10-31 17:41:15 +080051 .states = {
52 [0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
Joseph Lod457ef352012-10-31 17:41:17 +080053#ifdef CONFIG_PM_SLEEP
54 [1] = {
55 .enter = tegra30_idle_lp2,
56 .exit_latency = 2000,
57 .target_residency = 2200,
58 .power_usage = 0,
59 .flags = CPUIDLE_FLAG_TIME_VALID,
60 .name = "powered-down",
61 .desc = "CPU power gated",
62 },
63#endif
Joseph Lo0b25e252012-10-31 17:41:15 +080064 },
65};
66
67static DEFINE_PER_CPU(struct cpuidle_device, tegra_idle_device);
68
Joseph Lod457ef352012-10-31 17:41:17 +080069#ifdef CONFIG_PM_SLEEP
70#ifdef CONFIG_SMP
71static bool tegra30_cpu_core_power_down(struct cpuidle_device *dev,
72 struct cpuidle_driver *drv,
73 int index)
74{
75 clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu);
76
77 smp_wmb();
78
79 save_cpu_arch_register();
80
81 cpu_suspend(0, tegra30_sleep_cpu_secondary_finish);
82
83 restore_cpu_arch_register();
84
85 clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);
86
87 return true;
88}
89#else
90static inline bool tegra30_cpu_core_power_down(struct cpuidle_device *dev,
91 struct cpuidle_driver *drv,
92 int index)
93{
94 return true;
95}
96#endif
97
98static int __cpuinit tegra30_idle_lp2(struct cpuidle_device *dev,
99 struct cpuidle_driver *drv,
100 int index)
101{
102 u32 cpu = is_smp() ? cpu_logical_map(dev->cpu) : dev->cpu;
103 bool entered_lp2 = false;
104
105 local_fiq_disable();
106
107 tegra_set_cpu_in_lp2(cpu);
108 cpu_pm_enter();
109
110 if (cpu == 0)
111 cpu_do_idle();
112 else
113 entered_lp2 = tegra30_cpu_core_power_down(dev, drv, index);
114
115 cpu_pm_exit();
116 tegra_clear_cpu_in_lp2(cpu);
117
118 local_fiq_enable();
119
120 smp_rmb();
121
122 return (entered_lp2) ? index : 0;
123}
124#endif
125
Joseph Lo0b25e252012-10-31 17:41:15 +0800126int __init tegra30_cpuidle_init(void)
127{
128 int ret;
129 unsigned int cpu;
130 struct cpuidle_device *dev;
131 struct cpuidle_driver *drv = &tegra_idle_driver;
132
133 ret = cpuidle_register_driver(&tegra_idle_driver);
134 if (ret) {
135 pr_err("CPUidle driver registration failed\n");
136 return ret;
137 }
138
139 for_each_possible_cpu(cpu) {
140 dev = &per_cpu(tegra_idle_device, cpu);
141 dev->cpu = cpu;
142
143 dev->state_count = drv->state_count;
144 ret = cpuidle_register_device(dev);
145 if (ret) {
146 pr_err("CPU%u: CPUidle device registration failed\n",
147 cpu);
148 return ret;
149 }
150 }
151 return 0;
152}