1 /* linux/arch/arm/mach-s3c64xx/cpuidle.c
3 * Copyright (c) 2011 Wolfson Microelectronics, plc
4 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com
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.
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/cpuidle.h>
16 #include <linux/export.h>
17 #include <linux/time.h>
19 #include <asm/proc-fns.h>
23 #include <mach/regs-sys.h>
24 #include <mach/regs-syscon-power.h>
26 static int s3c64xx_enter_idle(struct cpuidle_device
*dev
,
27 struct cpuidle_driver
*drv
,
30 struct timeval before
, after
;
35 do_gettimeofday(&before
);
37 /* Setup PWRCFG to enter idle mode */
38 tmp
= __raw_readl(S3C64XX_PWR_CFG
);
39 tmp
&= ~S3C64XX_PWRCFG_CFG_WFI_MASK
;
40 tmp
|= S3C64XX_PWRCFG_CFG_WFI_IDLE
;
41 __raw_writel(tmp
, S3C64XX_PWR_CFG
);
45 do_gettimeofday(&after
);
47 idle_time
= (after
.tv_sec
- before
.tv_sec
) * USEC_PER_SEC
+
48 (after
.tv_usec
- before
.tv_usec
);
50 dev
->last_residency
= idle_time
;
54 static struct cpuidle_state s3c64xx_cpuidle_set
[] = {
56 .enter
= s3c64xx_enter_idle
,
58 .target_residency
= 1,
59 .flags
= CPUIDLE_FLAG_TIME_VALID
,
61 .desc
= "System active, ARM gated",
65 static struct cpuidle_driver s3c64xx_cpuidle_driver
= {
66 .name
= "s3c64xx_cpuidle",
68 .state_count
= ARRAY_SIZE(s3c64xx_cpuidle_set
),
71 static struct cpuidle_device s3c64xx_cpuidle_device
= {
72 .state_count
= ARRAY_SIZE(s3c64xx_cpuidle_set
),
75 static int __init
s3c64xx_init_cpuidle(void)
79 memcpy(s3c64xx_cpuidle_driver
.states
, s3c64xx_cpuidle_set
,
80 sizeof(s3c64xx_cpuidle_set
));
81 cpuidle_register_driver(&s3c64xx_cpuidle_driver
);
83 ret
= cpuidle_register_device(&s3c64xx_cpuidle_device
);
85 pr_err("Failed to register cpuidle device: %d\n", ret
);
91 device_initcall(s3c64xx_init_cpuidle
);