1 // SPDX-License-Identifier: GPL-2.0-only
3  * PSCI CPU idle driver.
9 #define pr_fmt(fmt) "CPUidle PSCI: " fmt
21 #include <linux/psci.h>
29 #include "cpuidle-psci.h"
61 	u32 *states = data->psci_states;  in __psci_enter_domain_idle_state()
62 	struct device *pd_dev = data->dev;  in __psci_enter_domain_idle_state()
68 		return -1;  in __psci_enter_domain_idle_state()
82 	ret = psci_cpu_suspend_enter(state) ? -1 : idx;  in __psci_enter_domain_idle_state()
94 	psci_set_domain_state(0);  in __psci_enter_domain_idle_state()
118 	return 0;  in psci_idle_cpuhp_up()
128 		psci_set_domain_state(0);  in psci_idle_cpuhp_down()
131 	return 0;  in psci_idle_cpuhp_down()
142 					"cpuidle/psci:online",  in psci_idle_init_cpuhp()
158 	{ .compatible = "arm,idle-state",
165 	int err = of_property_read_u32(np, "arm,psci-suspend-param", state);  in psci_dt_parse_state_node()
168 		pr_warn("%pOF missing arm,psci-suspend-param property\n", np);  in psci_dt_parse_state_node()
173 		pr_warn("Invalid PSCI power state %#x\n", *state);  in psci_dt_parse_state_node()
174 		return -EINVAL;  in psci_dt_parse_state_node()
177 	return 0;  in psci_dt_parse_state_node()
186 		return 0;  in psci_dt_cpu_init_topology()
188 	data->dev = psci_dt_attach_cpu(cpu);  in psci_dt_cpu_init_topology()
189 	if (IS_ERR_OR_NULL(data->dev))  in psci_dt_cpu_init_topology()
190 		return PTR_ERR_OR_ZERO(data->dev);  in psci_dt_cpu_init_topology()
197 	drv->states[state_count - 1].enter = psci_enter_domain_idle_state;  in psci_dt_cpu_init_topology()
198 	drv->states[state_count - 1].enter_s2idle = psci_enter_s2idle_domain_idle_state;  in psci_dt_cpu_init_topology()
201 	return 0;  in psci_dt_cpu_init_topology()
208 	int i, ret = 0;  in psci_dt_cpu_init_idle()
217 		return -ENOMEM;  in psci_dt_cpu_init_idle()
220 		state_node = of_get_cpu_state_node(cpu_node, i - 1);  in psci_dt_cpu_init_idle()
230 		pr_debug("psci-power-state %#x index %d\n", psci_states[i], i);  in psci_dt_cpu_init_idle()
234 		return -ENODEV;  in psci_dt_cpu_init_idle()
238 	if (ret < 0)  in psci_dt_cpu_init_idle()
241 	/* Idle states parsed correctly, store them in the per-cpu struct. */  in psci_dt_cpu_init_idle()
242 	data->psci_states = psci_states;  in psci_dt_cpu_init_idle()
243 	return 0;  in psci_dt_cpu_init_idle()
253 	 * If the PSCI cpu_suspend function hook has not been initialized  in psci_cpu_init_idle()
257 		return -EOPNOTSUPP;  in psci_cpu_init_idle()
261 		return -ENODEV;  in psci_cpu_init_idle()
274 	psci_dt_detach_cpu(data->dev);  in psci_cpu_deinit_idle()
283 	int ret = 0;  in psci_idle_init_cpu()
287 		return -ENODEV;  in psci_idle_init_cpu()
290 	 * Check whether the enable-method for the cpu is PSCI, fail  in psci_idle_init_cpu()
293 	enable_method = of_get_property(cpu_node, "enable-method", NULL);  in psci_idle_init_cpu()
294 	if (!enable_method || (strcmp(enable_method, "psci")))  in psci_idle_init_cpu()
295 		ret = -ENODEV;  in psci_idle_init_cpu()
303 		return -ENOMEM;  in psci_idle_init_cpu()
305 	drv->name = "psci_idle";  in psci_idle_init_cpu()
306 	drv->owner = THIS_MODULE;  in psci_idle_init_cpu()
307 	drv->cpumask = (struct cpumask *)cpumask_of(cpu);  in psci_idle_init_cpu()
310 	 * PSCI idle states relies on architectural WFI to be represented as  in psci_idle_init_cpu()
311 	 * state index 0.  in psci_idle_init_cpu()
313 	drv->states[0].enter = psci_enter_idle_state;  in psci_idle_init_cpu()
314 	drv->states[0].exit_latency = 1;  in psci_idle_init_cpu()
315 	drv->states[0].target_residency = 1;  in psci_idle_init_cpu()
316 	drv->states[0].power_usage = UINT_MAX;  in psci_idle_init_cpu()
317 	strcpy(drv->states[0].name, "WFI");  in psci_idle_init_cpu()
318 	strcpy(drv->states[0].desc, "ARM WFI");  in psci_idle_init_cpu()
321 	 * If no DT idle states are detected (ret == 0) let the driver  in psci_idle_init_cpu()
324 	 * default archictectural back-end already executes wfi  in psci_idle_init_cpu()
328 	if (ret <= 0)  in psci_idle_init_cpu()
329 		return ret ? : -ENODEV;  in psci_idle_init_cpu()
332 	 * Initialize PSCI idle states.  in psci_idle_init_cpu()
336 		pr_err("CPU %d failed to PSCI idle\n", cpu);  in psci_idle_init_cpu()
346 	return 0;  in psci_idle_init_cpu()
353  * psci_idle_probe - Initializes PSCI cpuidle driver
355  * Initializes PSCI cpuidle driver for all CPUs, if any CPU fails
366 		ret = psci_idle_init_cpu(&pdev->dev, cpu);  in psci_cpuidle_probe()
372 	return 0;  in psci_cpuidle_probe()
375 	while (--cpu >= 0) {  in psci_cpuidle_probe()
388 		.name = "psci-cpuidle",
401 	pdev = platform_device_register_simple("psci-cpuidle", -1, NULL, 0);  in psci_idle_init()
407 	return 0;  in psci_idle_init()