https://github.com/torvalds/linux
Tip revision: 3d7cb6b04c3f3115719235cc6866b10326de34cd authored by Linus Torvalds on 31 July 2022, 21:03:01 UTC
Linux 5.19
Linux 5.19
Tip revision: 3d7cb6b
cpuidle-qcom-spm.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2011-2014, The Linux Foundation. All rights reserved.
* Copyright (c) 2014,2015, Linaro Ltd.
*
* SAW power controller driver
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/cpuidle.h>
#include <linux/cpu_pm.h>
#include <linux/qcom_scm.h>
#include <soc/qcom/spm.h>
#include <asm/proc-fns.h>
#include <asm/suspend.h>
#include "dt_idle_states.h"
struct cpuidle_qcom_spm_data {
struct cpuidle_driver cpuidle_driver;
struct spm_driver_data *spm;
};
static int qcom_pm_collapse(unsigned long int unused)
{
qcom_scm_cpu_power_down(QCOM_SCM_CPU_PWR_DOWN_L2_ON);
/*
* Returns here only if there was a pending interrupt and we did not
* power down as a result.
*/
return -1;
}
static int qcom_cpu_spc(struct spm_driver_data *drv)
{
int ret;
spm_set_low_power_mode(drv, PM_SLEEP_MODE_SPC);
ret = cpu_suspend(0, qcom_pm_collapse);
/*
* ARM common code executes WFI without calling into our driver and
* if the SPM mode is not reset, then we may accidently power down the
* cpu when we intended only to gate the cpu clock.
* Ensure the state is set to standby before returning.
*/
spm_set_low_power_mode(drv, PM_SLEEP_MODE_STBY);
return ret;
}
static int spm_enter_idle_state(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int idx)
{
struct cpuidle_qcom_spm_data *data = container_of(drv, struct cpuidle_qcom_spm_data,
cpuidle_driver);
return CPU_PM_CPU_IDLE_ENTER_PARAM(qcom_cpu_spc, idx, data->spm);
}
static struct cpuidle_driver qcom_spm_idle_driver = {
.name = "qcom_spm",
.owner = THIS_MODULE,
.states[0] = {
.enter = spm_enter_idle_state,
.exit_latency = 1,
.target_residency = 1,
.power_usage = UINT_MAX,
.name = "WFI",
.desc = "ARM WFI",
}
};
static const struct of_device_id qcom_idle_state_match[] = {
{ .compatible = "qcom,idle-state-spc", .data = spm_enter_idle_state },
{ },
};
static int spm_cpuidle_register(struct device *cpuidle_dev, int cpu)
{
struct platform_device *pdev = NULL;
struct device_node *cpu_node, *saw_node;
struct cpuidle_qcom_spm_data *data = NULL;
int ret;
cpu_node = of_cpu_device_node_get(cpu);
if (!cpu_node)
return -ENODEV;
saw_node = of_parse_phandle(cpu_node, "qcom,saw", 0);
if (!saw_node)
return -ENODEV;
pdev = of_find_device_by_node(saw_node);
of_node_put(saw_node);
of_node_put(cpu_node);
if (!pdev)
return -ENODEV;
data = devm_kzalloc(cpuidle_dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->spm = dev_get_drvdata(&pdev->dev);
if (!data->spm)
return -EINVAL;
data->cpuidle_driver = qcom_spm_idle_driver;
data->cpuidle_driver.cpumask = (struct cpumask *)cpumask_of(cpu);
ret = dt_init_idle_driver(&data->cpuidle_driver,
qcom_idle_state_match, 1);
if (ret <= 0)
return ret ? : -ENODEV;
return cpuidle_register(&data->cpuidle_driver, NULL);
}
static int spm_cpuidle_drv_probe(struct platform_device *pdev)
{
int cpu, ret;
if (!qcom_scm_is_available())
return -EPROBE_DEFER;
ret = qcom_scm_set_warm_boot_addr(cpu_resume_arm);
if (ret)
return dev_err_probe(&pdev->dev, ret, "set warm boot addr failed");
for_each_possible_cpu(cpu) {
ret = spm_cpuidle_register(&pdev->dev, cpu);
if (ret && ret != -ENODEV) {
dev_err(&pdev->dev,
"Cannot register for CPU%d: %d\n", cpu, ret);
}
}
return 0;
}
static struct platform_driver spm_cpuidle_driver = {
.probe = spm_cpuidle_drv_probe,
.driver = {
.name = "qcom-spm-cpuidle",
.suppress_bind_attrs = true,
},
};
static bool __init qcom_spm_find_any_cpu(void)
{
struct device_node *cpu_node, *saw_node;
for_each_of_cpu_node(cpu_node) {
saw_node = of_parse_phandle(cpu_node, "qcom,saw", 0);
if (of_device_is_available(saw_node)) {
of_node_put(saw_node);
of_node_put(cpu_node);
return true;
}
of_node_put(saw_node);
}
return false;
}
static int __init qcom_spm_cpuidle_init(void)
{
struct platform_device *pdev;
int ret;
ret = platform_driver_register(&spm_cpuidle_driver);
if (ret)
return ret;
/* Make sure there is actually any CPU managed by the SPM */
if (!qcom_spm_find_any_cpu())
return 0;
pdev = platform_device_register_simple("qcom-spm-cpuidle",
-1, NULL, 0);
if (IS_ERR(pdev)) {
platform_driver_unregister(&spm_cpuidle_driver);
return PTR_ERR(pdev);
}
return 0;
}
device_initcall(qcom_spm_cpuidle_init);