1 // SPDX-License-Identifier: GPL-2.0-only
3  * PSCI CPU idle driver.
29 #include "cpuidle-psci.h"
58 	u32 *states = data->psci_states;  in __psci_enter_domain_idle_state()
59 	struct device *pd_dev = data->dev;  in __psci_enter_domain_idle_state()
65 		return -1;  in __psci_enter_domain_idle_state()
67 	/* Do runtime PM to manage a hierarchical CPU toplogy. */  in __psci_enter_domain_idle_state()
77 	ret = psci_cpu_suspend_enter(state) ? -1 : idx;  in __psci_enter_domain_idle_state()
86 	/* Clear the domain state to start fresh when back from idle. */  in __psci_enter_domain_idle_state()
120 		/* Clear domain state to start fresh at next online. */  in psci_idle_cpuhp_down()
127 static void psci_idle_syscore_switch(bool suspend)  in psci_idle_syscore_switch()  argument
134 		dev = per_cpu_ptr(&psci_cpuidle_data, cpu)->dev;  in psci_idle_syscore_switch()
136 		if (dev && suspend) {  in psci_idle_syscore_switch()
145 			/* Clear domain state to re-start fresh. */  in psci_idle_syscore_switch()
166 	.suspend = psci_idle_syscore_suspend,
200 	{ .compatible = "arm,idle-state",
207 	int err = of_property_read_u32(np, "arm,psci-suspend-param", state);  in psci_dt_parse_state_node()
210 		pr_warn("%pOF missing arm,psci-suspend-param property\n", np);  in psci_dt_parse_state_node()
216 		return -EINVAL;  in psci_dt_parse_state_node()
226 	/* Currently limit the hierarchical topology to be used in OSI mode. */  in psci_dt_cpu_init_topology()
230 	data->dev = dt_idle_attach_cpu(cpu, "psci");  in psci_dt_cpu_init_topology()
231 	if (IS_ERR_OR_NULL(data->dev))  in psci_dt_cpu_init_topology()
232 		return PTR_ERR_OR_ZERO(data->dev);  in psci_dt_cpu_init_topology()
237 	 * Using the deepest state for the CPU to trigger a potential selection  in psci_dt_cpu_init_topology()
239 	 * deeper states. On PREEMPT_RT the hierarchical topology is limited to  in psci_dt_cpu_init_topology()
242 	drv->states[state_count - 1].enter_s2idle = psci_enter_s2idle_domain_idle_state;  in psci_dt_cpu_init_topology()
244 		drv->states[state_count - 1].enter = psci_enter_domain_idle_state;  in psci_dt_cpu_init_topology()
264 		return -ENOMEM;  in psci_dt_cpu_init_idle()
267 		state_node = of_get_cpu_state_node(cpu_node, i - 1);  in psci_dt_cpu_init_idle()
277 		pr_debug("psci-power-state %#x index %d\n", psci_states[i], i);  in psci_dt_cpu_init_idle()
281 		return -ENODEV;  in psci_dt_cpu_init_idle()
288 	/* Idle states parsed correctly, store them in the per-cpu struct. */  in psci_dt_cpu_init_idle()
289 	data->psci_states = psci_states;  in psci_dt_cpu_init_idle()
301 	 * idle states must not be enabled, so bail out  in psci_cpu_init_idle()
304 		return -EOPNOTSUPP;  in psci_cpu_init_idle()
308 		return -ENODEV;  in psci_cpu_init_idle()
321 	dt_idle_detach_cpu(data->dev);  in psci_cpu_deinit_idle()
335 		return -ENODEV;  in psci_idle_init_cpu()
338 	 * Check whether the enable-method for the cpu is PSCI, fail  in psci_idle_init_cpu()
341 	enable_method = of_get_property(cpu_node, "enable-method", NULL);  in psci_idle_init_cpu()
343 		ret = -ENODEV;  in psci_idle_init_cpu()
351 		return -ENOMEM;  in psci_idle_init_cpu()
353 	drv->name = "psci_idle";  in psci_idle_init_cpu()
354 	drv->owner = THIS_MODULE;  in psci_idle_init_cpu()
355 	drv->cpumask = (struct cpumask *)cpumask_of(cpu);  in psci_idle_init_cpu()
358 	 * PSCI idle states relies on architectural WFI to be represented as  in psci_idle_init_cpu()
361 	drv->states[0].enter = psci_enter_idle_state;  in psci_idle_init_cpu()
362 	drv->states[0].exit_latency = 1;  in psci_idle_init_cpu()
363 	drv->states[0].target_residency = 1;  in psci_idle_init_cpu()
364 	drv->states[0].power_usage = UINT_MAX;  in psci_idle_init_cpu()
365 	strcpy(drv->states[0].name, "WFI");  in psci_idle_init_cpu()
366 	strcpy(drv->states[0].desc, "ARM WFI");  in psci_idle_init_cpu()
369 	 * If no DT idle states are detected (ret == 0) let the driver  in psci_idle_init_cpu()
370 	 * initialization fail accordingly since there is no reason to  in psci_idle_init_cpu()
371 	 * initialize the idle driver if only wfi is supported, the  in psci_idle_init_cpu()
372 	 * default archictectural back-end already executes wfi  in psci_idle_init_cpu()
373 	 * on idle entry.  in psci_idle_init_cpu()
377 		return ret ? : -ENODEV;  in psci_idle_init_cpu()
380 	 * Initialize PSCI idle states.  in psci_idle_init_cpu()
384 		pr_err("CPU %d failed to PSCI idle\n", cpu);  in psci_idle_init_cpu()
401  * psci_idle_probe - Initializes PSCI cpuidle driver
404  * to register cpuidle driver then rollback to cancel all CPUs
414 		ret = psci_idle_init_cpu(&pdev->dev, cpu);  in psci_cpuidle_probe()
424 	while (--cpu >= 0) {  in psci_cpuidle_probe()
437 		.name = "psci-cpuidle",
450 	pdev = platform_device_register_simple("psci-cpuidle", -1, NULL, 0);  in psci_idle_init()