1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * CPU idle driver for Tegra CPUs
5 * Copyright (c) 2010-2012, NVIDIA Corporation.
6 * Copyright (c) 2011 Google, Inc.
7 * Author: Colin Cross <ccross@android.com>
8 * Gary King <gking@nvidia.com>
10 * Rework for 3.3 by Peter De Schrijver <pdeschrijver@nvidia.com>
13 #include <linux/clk/tegra.h>
14 #include <linux/tick.h>
15 #include <linux/cpuidle.h>
16 #include <linux/cpu_pm.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
20 #include <asm/cpuidle.h>
21 #include <asm/smp_plat.h>
22 #include <asm/suspend.h>
28 #ifdef CONFIG_PM_SLEEP
29 static int tegra30_idle_lp2(struct cpuidle_device *dev,
30 struct cpuidle_driver *drv,
34 static struct cpuidle_driver tegra_idle_driver = {
37 #ifdef CONFIG_PM_SLEEP
43 [0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
44 #ifdef CONFIG_PM_SLEEP
46 .enter = tegra30_idle_lp2,
48 .target_residency = 2200,
50 .flags = CPUIDLE_FLAG_TIMER_STOP,
51 .name = "powered-down",
52 .desc = "CPU power gated",
58 #ifdef CONFIG_PM_SLEEP
59 static bool tegra30_cpu_cluster_power_down(struct cpuidle_device *dev,
60 struct cpuidle_driver *drv,
63 /* All CPUs entering LP2 is not working.
64 * Don't let CPU0 enter LP2 when any secondary CPU is online.
66 if (num_online_cpus() > 1 || !tegra_cpu_rail_off_ready()) {
71 tegra_idle_lp2_last();
77 static bool tegra30_cpu_core_power_down(struct cpuidle_device *dev,
78 struct cpuidle_driver *drv,
83 cpu_suspend(0, tegra30_sleep_cpu_secondary_finish);
88 static inline bool tegra30_cpu_core_power_down(struct cpuidle_device *dev,
89 struct cpuidle_driver *drv,
96 static int tegra30_idle_lp2(struct cpuidle_device *dev,
97 struct cpuidle_driver *drv,
100 bool entered_lp2 = false;
105 last_cpu = tegra_set_cpu_in_lp2();
110 entered_lp2 = tegra30_cpu_cluster_power_down(dev, drv,
115 entered_lp2 = tegra30_cpu_core_power_down(dev, drv, index);
119 tegra_clear_cpu_in_lp2();
125 return (entered_lp2) ? index : 0;
129 int __init tegra30_cpuidle_init(void)
131 return cpuidle_register(&tegra_idle_driver, NULL);