mirror of
https://github.com/torvalds/linux.git
synced 2024-11-12 07:01:57 +00:00
e35db92b4f
* pm-cpuidle: ARM: cpuidle: Fix error return code * pm-opp: PM / OPP: Don't support OPP if it provides supported-hw but platform does not PM / OPP: avoid maybe-uninitialized warning * pm-avs: PM / AVS: SmartReflex: Neaten logging
151 lines
3.7 KiB
C
151 lines
3.7 KiB
C
/*
|
|
* ARM/ARM64 generic CPU idle driver.
|
|
*
|
|
* Copyright (C) 2014 ARM Ltd.
|
|
* Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "CPUidle arm: " fmt
|
|
|
|
#include <linux/cpuidle.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/cpu_pm.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include <asm/cpuidle.h>
|
|
|
|
#include "dt_idle_states.h"
|
|
|
|
/*
|
|
* arm_enter_idle_state - Programs CPU to enter the specified state
|
|
*
|
|
* dev: cpuidle device
|
|
* drv: cpuidle driver
|
|
* idx: state index
|
|
*
|
|
* Called from the CPUidle framework to program the device to the
|
|
* specified target state selected by the governor.
|
|
*/
|
|
static int arm_enter_idle_state(struct cpuidle_device *dev,
|
|
struct cpuidle_driver *drv, int idx)
|
|
{
|
|
/*
|
|
* Pass idle state index to arm_cpuidle_suspend which in turn
|
|
* will call the CPU ops suspend protocol with idle index as a
|
|
* parameter.
|
|
*/
|
|
return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, idx);
|
|
}
|
|
|
|
static struct cpuidle_driver arm_idle_driver = {
|
|
.name = "arm_idle",
|
|
.owner = THIS_MODULE,
|
|
/*
|
|
* State at index 0 is standby wfi and considered standard
|
|
* on all ARM platforms. If in some platforms simple wfi
|
|
* can't be used as "state 0", DT bindings must be implemented
|
|
* to work around this issue and allow installing a special
|
|
* handler for idle state index 0.
|
|
*/
|
|
.states[0] = {
|
|
.enter = arm_enter_idle_state,
|
|
.exit_latency = 1,
|
|
.target_residency = 1,
|
|
.power_usage = UINT_MAX,
|
|
.name = "WFI",
|
|
.desc = "ARM WFI",
|
|
}
|
|
};
|
|
|
|
static const struct of_device_id arm_idle_state_match[] __initconst = {
|
|
{ .compatible = "arm,idle-state",
|
|
.data = arm_enter_idle_state },
|
|
{ },
|
|
};
|
|
|
|
/*
|
|
* arm_idle_init
|
|
*
|
|
* Registers the arm specific cpuidle driver with the cpuidle
|
|
* framework. It relies on core code to parse the idle states
|
|
* and initialize them using driver data structures accordingly.
|
|
*/
|
|
static int __init arm_idle_init(void)
|
|
{
|
|
int cpu, ret;
|
|
struct cpuidle_driver *drv = &arm_idle_driver;
|
|
struct cpuidle_device *dev;
|
|
|
|
/*
|
|
* Initialize idle states data, starting at index 1.
|
|
* This driver is DT only, if no DT idle states are detected (ret == 0)
|
|
* let the driver initialization fail accordingly since there is no
|
|
* reason to initialize the idle driver if only wfi is supported.
|
|
*/
|
|
ret = dt_init_idle_driver(drv, arm_idle_state_match, 1);
|
|
if (ret <= 0)
|
|
return ret ? : -ENODEV;
|
|
|
|
ret = cpuidle_register_driver(drv);
|
|
if (ret) {
|
|
pr_err("Failed to register cpuidle driver\n");
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Call arch CPU operations in order to initialize
|
|
* idle states suspend back-end specific data
|
|
*/
|
|
for_each_possible_cpu(cpu) {
|
|
ret = arm_cpuidle_init(cpu);
|
|
|
|
/*
|
|
* Skip the cpuidle device initialization if the reported
|
|
* failure is a HW misconfiguration/breakage (-ENXIO).
|
|
*/
|
|
if (ret == -ENXIO)
|
|
continue;
|
|
|
|
if (ret) {
|
|
pr_err("CPU %d failed to init idle CPU ops\n", cpu);
|
|
goto out_fail;
|
|
}
|
|
|
|
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
|
|
if (!dev) {
|
|
pr_err("Failed to allocate cpuidle device\n");
|
|
ret = -ENOMEM;
|
|
goto out_fail;
|
|
}
|
|
dev->cpu = cpu;
|
|
|
|
ret = cpuidle_register_device(dev);
|
|
if (ret) {
|
|
pr_err("Failed to register cpuidle device for CPU %d\n",
|
|
cpu);
|
|
kfree(dev);
|
|
goto out_fail;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
out_fail:
|
|
while (--cpu >= 0) {
|
|
dev = per_cpu(cpuidle_devices, cpu);
|
|
cpuidle_unregister_device(dev);
|
|
kfree(dev);
|
|
}
|
|
|
|
cpuidle_unregister_driver(drv);
|
|
|
|
return ret;
|
|
}
|
|
device_initcall(arm_idle_init);
|