1 // SPDX-License-Identifier: GPL-2.0-only
3  * DT idle states parsing code.
9 #define pr_fmt(fmt) "DT idle-states: " fmt
29 	 * pointer of the passed in struct of_device_id array to the idle  in init_state_node()
32 	idle_state->enter = match_id->data;  in init_state_node()
38 	idle_state->enter_s2idle = match_id->data;  in init_state_node()
40 	err = of_property_read_u32(state_node, "wakeup-latency-us",  in init_state_node()
41 				   &idle_state->exit_latency);  in init_state_node()
45 		err = of_property_read_u32(state_node, "entry-latency-us",  in init_state_node()
48 			pr_debug(" * %pOF missing entry-latency-us property\n",  in init_state_node()
50 			return -EINVAL;  in init_state_node()
53 		err = of_property_read_u32(state_node, "exit-latency-us",  in init_state_node()
56 			pr_debug(" * %pOF missing exit-latency-us property\n",  in init_state_node()
58 			return -EINVAL;  in init_state_node()
61 		 * If wakeup-latency-us is missing, default to entry+exit  in init_state_node()
62 		 * latencies as defined in idle states bindings  in init_state_node()
64 		idle_state->exit_latency = entry_latency + exit_latency;  in init_state_node()
67 	err = of_property_read_u32(state_node, "min-residency-us",  in init_state_node()
68 				   &idle_state->target_residency);  in init_state_node()
70 		pr_debug(" * %pOF missing min-residency-us property\n",  in init_state_node()
72 		return -EINVAL;  in init_state_node()
75 	err = of_property_read_string(state_node, "idle-state-name", &desc);  in init_state_node()
77 		desc = state_node->name;  in init_state_node()
79 	idle_state->flags = CPUIDLE_FLAG_RCU_IDLE;  in init_state_node()
80 	if (of_property_read_bool(state_node, "local-timer-stop"))  in init_state_node()
81 		idle_state->flags |= CPUIDLE_FLAG_TIMER_STOP;  in init_state_node()
87 	strscpy(idle_state->name, state_node->name, CPUIDLE_NAME_LEN);  in init_state_node()
88 	strscpy(idle_state->desc, desc, CPUIDLE_DESC_LEN);  in init_state_node()
93  * Check that the idle state is uniform across all CPUs in the CPUidle driver
104 	 * Compare idle state phandles for index idx on all CPUs in the  in idle_state_valid()
127  * dt_init_idle_driver() - Parse the DT idle states and initialize the
128  *			   idle driver states array
129  * @drv:	  Pointer to CPU idle driver to be initialized
131  *		  compatible idle state nodes. The data pointer for each valid
140  * @start_idx:    First idle state index to be initialized
142  * If DT idle states are detected and are valid the state count and states
146  * Return: number of valid DT idle states parsed, <0 on failure
160 		return -EINVAL;  in dt_init_idle_driver()
162 	 * We get the idle states for the first logical cpu in the  in dt_init_idle_driver()
167 	cpumask = drv->cpumask ? : cpu_possible_mask;  in dt_init_idle_driver()
177 			err = -ENODEV;  in dt_init_idle_driver()
187 			pr_warn("%pOF idle state not valid, bailing out\n",  in dt_init_idle_driver()
189 			err = -EINVAL;  in dt_init_idle_driver()
194 			pr_warn("State index reached static CPU idle driver states array size\n");  in dt_init_idle_driver()
198 		idle_state = &drv->states[state_idx++];  in dt_init_idle_driver()
201 			pr_err("Parsing idle state node %pOF failed with err %d\n",  in dt_init_idle_driver()
203 			err = -EINVAL;  in dt_init_idle_driver()
214 	/* Set the number of total supported idle states. */  in dt_init_idle_driver()
215 	drv->state_count = state_idx;  in dt_init_idle_driver()
218 	 * Return the number of present and valid DT idle states, which can  in dt_init_idle_driver()
219 	 * also be 0 on platforms with missing DT idle states or legacy DT  in dt_init_idle_driver()
220 	 * configuration predating the DT idle states bindings.  in dt_init_idle_driver()
222 	return state_idx - start_idx;  in dt_init_idle_driver()