forked from Minki/linux
22b8b85d90
CPUidle driver for tegra. In this version only LP3 (clockgating) is supported. Based on work by: Colin Cross <ccross@android.com> Gary King <gking@nvidia.com> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com> Acked-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Acked-by: Colin Cross <ccross@android.com> Signed-off-by: Olof Johansson <olof@lixom.net>
108 lines
2.5 KiB
C
108 lines
2.5 KiB
C
/*
|
|
* arch/arm/mach-tegra/cpuidle.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/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/cpu.h>
|
|
#include <linux/cpuidle.h>
|
|
#include <linux/hrtimer.h>
|
|
|
|
#include <mach/iomap.h>
|
|
|
|
extern void tegra_cpu_wfi(void);
|
|
|
|
static int tegra_idle_enter_lp3(struct cpuidle_device *dev,
|
|
struct cpuidle_driver *drv, int index);
|
|
|
|
struct cpuidle_driver tegra_idle_driver = {
|
|
.name = "tegra_idle",
|
|
.owner = THIS_MODULE,
|
|
.state_count = 1,
|
|
.states = {
|
|
[0] = {
|
|
.enter = tegra_idle_enter_lp3,
|
|
.exit_latency = 10,
|
|
.target_residency = 10,
|
|
.power_usage = 600,
|
|
.flags = CPUIDLE_FLAG_TIME_VALID,
|
|
.name = "LP3",
|
|
.desc = "CPU flow-controlled",
|
|
},
|
|
},
|
|
};
|
|
|
|
static DEFINE_PER_CPU(struct cpuidle_device, tegra_idle_device);
|
|
|
|
static int tegra_idle_enter_lp3(struct cpuidle_device *dev,
|
|
struct cpuidle_driver *drv, int index)
|
|
{
|
|
ktime_t enter, exit;
|
|
s64 us;
|
|
|
|
local_irq_disable();
|
|
local_fiq_disable();
|
|
|
|
enter = ktime_get();
|
|
|
|
tegra_cpu_wfi();
|
|
|
|
exit = ktime_sub(ktime_get(), enter);
|
|
us = ktime_to_us(exit);
|
|
|
|
local_fiq_enable();
|
|
local_irq_enable();
|
|
|
|
dev->last_residency = us;
|
|
|
|
return index;
|
|
}
|
|
|
|
static int __init tegra_cpuidle_init(void)
|
|
{
|
|
int ret;
|
|
unsigned int cpu;
|
|
struct cpuidle_device *dev;
|
|
struct cpuidle_driver *drv = &tegra_idle_driver;
|
|
|
|
ret = cpuidle_register_driver(&tegra_idle_driver);
|
|
if (ret) {
|
|
pr_err("CPUidle driver registration failed\n");
|
|
return ret;
|
|
}
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
dev = &per_cpu(tegra_idle_device, cpu);
|
|
dev->cpu = cpu;
|
|
|
|
dev->state_count = drv->state_count;
|
|
ret = cpuidle_register_device(dev);
|
|
if (ret) {
|
|
pr_err("CPU%u: CPUidle device registration failed\n",
|
|
cpu);
|
|
return ret;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
device_initcall(tegra_cpuidle_init);
|