linux/arch/arm/mach-tegra/cpuidle-tegra30.c
Dmitry Osipenko 36841ba279 ARM: tegra: cpuidle: Handle tick broadcasting within cpuidle core on Tegra20/30
Tegra20/30 drivers do not handle the tick_broadcast_enter() error which
potentially could happen when CPU timer isn't permitted to be stopped.
Let's just move out the broadcasting to the CPUIDLE core by setting the
respective flag in the Tegra20/30 drivers. This patch doesn't fix any
problem because currently tick_broadcast_enter() could fail only on
ARM64, so consider this change as a minor cleanup.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-04-18 11:32:57 +02:00

142 lines
3.1 KiB
C

/*
* CPU idle driver for Tegra CPUs
*
* Copyright (c) 2010-2012, NVIDIA Corporation.
* Copyright (c) 2011 Google, Inc.
* Author: Colin Cross <ccross@android.com>
* Gary King <gking@nvidia.com>
*
* Rework for 3.3 by Peter De Schrijver <pdeschrijver@nvidia.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/clk/tegra.h>
#include <linux/tick.h>
#include <linux/cpuidle.h>
#include <linux/cpu_pm.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/cpuidle.h>
#include <asm/smp_plat.h>
#include <asm/suspend.h>
#include "cpuidle.h"
#include "pm.h"
#include "sleep.h"
#ifdef CONFIG_PM_SLEEP
static int tegra30_idle_lp2(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index);
#endif
static struct cpuidle_driver tegra_idle_driver = {
.name = "tegra_idle",
.owner = THIS_MODULE,
#ifdef CONFIG_PM_SLEEP
.state_count = 2,
#else
.state_count = 1,
#endif
.states = {
[0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
#ifdef CONFIG_PM_SLEEP
[1] = {
.enter = tegra30_idle_lp2,
.exit_latency = 2000,
.target_residency = 2200,
.power_usage = 0,
.flags = CPUIDLE_FLAG_TIMER_STOP,
.name = "powered-down",
.desc = "CPU power gated",
},
#endif
},
};
#ifdef CONFIG_PM_SLEEP
static bool tegra30_cpu_cluster_power_down(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
/* All CPUs entering LP2 is not working.
* Don't let CPU0 enter LP2 when any secondary CPU is online.
*/
if (num_online_cpus() > 1 || !tegra_cpu_rail_off_ready()) {
cpu_do_idle();
return false;
}
tegra_idle_lp2_last();
return true;
}
#ifdef CONFIG_SMP
static bool tegra30_cpu_core_power_down(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
smp_wmb();
cpu_suspend(0, tegra30_sleep_cpu_secondary_finish);
return true;
}
#else
static inline bool tegra30_cpu_core_power_down(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
return true;
}
#endif
static int tegra30_idle_lp2(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
bool entered_lp2 = false;
bool last_cpu;
local_fiq_disable();
last_cpu = tegra_set_cpu_in_lp2();
cpu_pm_enter();
if (dev->cpu == 0) {
if (last_cpu)
entered_lp2 = tegra30_cpu_cluster_power_down(dev, drv,
index);
else
cpu_do_idle();
} else {
entered_lp2 = tegra30_cpu_core_power_down(dev, drv, index);
}
cpu_pm_exit();
tegra_clear_cpu_in_lp2();
local_fiq_enable();
smp_rmb();
return (entered_lp2) ? index : 0;
}
#endif
int __init tegra30_cpuidle_init(void)
{
return cpuidle_register(&tegra_idle_driver, NULL);
}