xref: /linux/arch/arm/mach-imx/cpuidle-imx6sl.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2  * Copyright (C) 2014 Freescale Semiconductor, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/cpuidle.h>
10 #include <linux/module.h>
11 #include <asm/cpuidle.h>
12 #include <asm/proc-fns.h>
13 
14 #include "common.h"
15 #include "cpuidle.h"
16 
17 static int imx6sl_enter_wait(struct cpuidle_device *dev,
18 			    struct cpuidle_driver *drv, int index)
19 {
20 	imx6q_set_lpm(WAIT_UNCLOCKED);
21 	/*
22 	 * Software workaround for ERR005311, see function
23 	 * description for details.
24 	 */
25 	imx6sl_set_wait_clk(true);
26 	cpu_do_idle();
27 	imx6sl_set_wait_clk(false);
28 	imx6q_set_lpm(WAIT_CLOCKED);
29 
30 	return index;
31 }
32 
33 static struct cpuidle_driver imx6sl_cpuidle_driver = {
34 	.name = "imx6sl_cpuidle",
35 	.owner = THIS_MODULE,
36 	.states = {
37 		/* WFI */
38 		ARM_CPUIDLE_WFI_STATE,
39 		/* WAIT */
40 		{
41 			.exit_latency = 50,
42 			.target_residency = 75,
43 			.flags = CPUIDLE_FLAG_TIME_VALID |
44 				CPUIDLE_FLAG_TIMER_STOP,
45 			.enter = imx6sl_enter_wait,
46 			.name = "WAIT",
47 			.desc = "Clock off",
48 		},
49 	},
50 	.state_count = 2,
51 	.safe_state_index = 0,
52 };
53 
54 int __init imx6sl_cpuidle_init(void)
55 {
56 	return cpuidle_register(&imx6sl_cpuidle_driver, NULL);
57 }
58