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path: root/drivers/cpuidle/cpuidle-qcom-spm.c
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Diffstat (limited to 'drivers/cpuidle/cpuidle-qcom-spm.c')
-rw-r--r--drivers/cpuidle/cpuidle-qcom-spm.c195
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);