1 /* linux/arch/arm/mach-s3c64xx/cpuidle.c
2 *
3 * Copyright (c) 2011 Wolfson Microelectronics, plc
4 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/cpuidle.h>
15 #include <linux/io.h>
16 #include <linux/export.h>
17 #include <linux/time.h>
18
19 #include <asm/cpuidle.h>
20
21 #include <plat/cpu.h>
22 #include <mach/map.h>
23
24 #include "regs-sys.h"
25 #include "regs-syscon-power.h"
26
s3c64xx_enter_idle(struct cpuidle_device * dev,struct cpuidle_driver * drv,int index)27 static int s3c64xx_enter_idle(struct cpuidle_device *dev,
28 struct cpuidle_driver *drv,
29 int index)
30 {
31 unsigned long tmp;
32
33 /* Setup PWRCFG to enter idle mode */
34 tmp = __raw_readl(S3C64XX_PWR_CFG);
35 tmp &= ~S3C64XX_PWRCFG_CFG_WFI_MASK;
36 tmp |= S3C64XX_PWRCFG_CFG_WFI_IDLE;
37 __raw_writel(tmp, S3C64XX_PWR_CFG);
38
39 cpu_do_idle();
40
41 return index;
42 }
43
44 static struct cpuidle_driver s3c64xx_cpuidle_driver = {
45 .name = "s3c64xx_cpuidle",
46 .owner = THIS_MODULE,
47 .states = {
48 {
49 .enter = s3c64xx_enter_idle,
50 .exit_latency = 1,
51 .target_residency = 1,
52 .name = "IDLE",
53 .desc = "System active, ARM gated",
54 },
55 },
56 .state_count = 1,
57 };
58
s3c64xx_init_cpuidle(void)59 static int __init s3c64xx_init_cpuidle(void)
60 {
61 if (soc_is_s3c64xx())
62 return cpuidle_register(&s3c64xx_cpuidle_driver, NULL);
63 return 0;
64 }
65 device_initcall(s3c64xx_init_cpuidle);
66