xref: /linux/arch/arm/mach-s3c/cpuidle-s3c64xx.c (revision 2da68a77)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2011 Wolfson Microelectronics, plc
4 // Copyright (c) 2011 Samsung Electronics Co., Ltd.
5 //		http://www.samsung.com
6 
7 #include <linux/kernel.h>
8 #include <linux/init.h>
9 #include <linux/cpuidle.h>
10 #include <linux/io.h>
11 #include <linux/export.h>
12 #include <linux/time.h>
13 
14 #include <asm/cpuidle.h>
15 
16 #include "cpu.h"
17 #include "map.h"
18 
19 #include "regs-sys-s3c64xx.h"
20 #include "regs-syscon-power-s3c64xx.h"
21 
22 static int s3c64xx_enter_idle(struct cpuidle_device *dev,
23 			      struct cpuidle_driver *drv,
24 			      int index)
25 {
26 	unsigned long tmp;
27 
28 	/* Setup PWRCFG to enter idle mode */
29 	tmp = __raw_readl(S3C64XX_PWR_CFG);
30 	tmp &= ~S3C64XX_PWRCFG_CFG_WFI_MASK;
31 	tmp |= S3C64XX_PWRCFG_CFG_WFI_IDLE;
32 	__raw_writel(tmp, S3C64XX_PWR_CFG);
33 
34 	cpu_do_idle();
35 
36 	return index;
37 }
38 
39 static struct cpuidle_driver s3c64xx_cpuidle_driver = {
40 	.name	= "s3c64xx_cpuidle",
41 	.owner  = THIS_MODULE,
42 	.states = {
43 		{
44 			.enter            = s3c64xx_enter_idle,
45 			.exit_latency     = 1,
46 			.target_residency = 1,
47 			.name             = "IDLE",
48 			.desc             = "System active, ARM gated",
49 		},
50 	},
51 	.state_count = 1,
52 };
53 
54 static int __init s3c64xx_init_cpuidle(void)
55 {
56 	if (soc_is_s3c64xx())
57 		return cpuidle_register(&s3c64xx_cpuidle_driver, NULL);
58 	return 0;
59 }
60 device_initcall(s3c64xx_init_cpuidle);
61