xref: /openbmc/linux/drivers/cpuidle/poll_state.c (revision ca481398)
1 /*
2  * poll_state.c - Polling idle state
3  *
4  * This file is released under the GPLv2.
5  */
6 
7 #include <linux/cpuidle.h>
8 #include <linux/sched.h>
9 #include <linux/sched/idle.h>
10 
11 static int __cpuidle poll_idle(struct cpuidle_device *dev,
12 			       struct cpuidle_driver *drv, int index)
13 {
14 	local_irq_enable();
15 	if (!current_set_polling_and_test()) {
16 		while (!need_resched())
17 			cpu_relax();
18 	}
19 	current_clr_polling();
20 
21 	return index;
22 }
23 
24 void cpuidle_poll_state_init(struct cpuidle_driver *drv)
25 {
26 	struct cpuidle_state *state = &drv->states[0];
27 
28 	snprintf(state->name, CPUIDLE_NAME_LEN, "POLL");
29 	snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
30 	state->exit_latency = 0;
31 	state->target_residency = 0;
32 	state->power_usage = -1;
33 	state->enter = poll_idle;
34 	state->disabled = false;
35 	state->flags = CPUIDLE_FLAG_POLLING;
36 }
37 EXPORT_SYMBOL_GPL(cpuidle_poll_state_init);
38