diff options
Diffstat (limited to 'drivers/cpuidle/cpuidle-qcom-spm.c')
| -rw-r--r-- | drivers/cpuidle/cpuidle-qcom-spm.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-qcom-spm.c b/drivers/cpuidle/cpuidle-qcom-spm.c new file mode 100644 index 0000000000..1fc9968eae --- /dev/null +++ b/drivers/cpuidle/cpuidle-qcom-spm.c @@ -0,0 +1,195 @@ +// 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_platform.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/cpuidle.h> +#include <linux/cpu_pm.h> +#include <linux/firmware/qcom/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 __cpuidle 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); |