-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
This patch supports cpuidle framework for EXYNOS4210. Currently, Only one idle state is possible to use, but more idle states can be added following by this patch. Signed-off-by: Jaecheol Lee <jc.lee@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
- Loading branch information
Jaecheol Lee
authored and
Kukjin Kim
committed
May 6, 2011
1 parent
0ee5623
commit 3d73998
Showing
2 changed files
with
87 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,86 @@ | ||
/* linux/arch/arm/mach-exynos4/cpuidle.c | ||
* | ||
* Copyright (c) 2011 Samsung Electronics Co., Ltd. | ||
* http://www.samsung.com | ||
* | ||
* This program is free software; you can redistribute it and/or modify | ||
* it under the terms of the GNU General Public License version 2 as | ||
* published by the Free Software Foundation. | ||
*/ | ||
|
||
#include <linux/kernel.h> | ||
#include <linux/init.h> | ||
#include <linux/cpuidle.h> | ||
#include <linux/io.h> | ||
|
||
#include <asm/proc-fns.h> | ||
|
||
static int exynos4_enter_idle(struct cpuidle_device *dev, | ||
struct cpuidle_state *state); | ||
|
||
static struct cpuidle_state exynos4_cpuidle_set[] = { | ||
[0] = { | ||
.enter = exynos4_enter_idle, | ||
.exit_latency = 1, | ||
.target_residency = 100000, | ||
.flags = CPUIDLE_FLAG_TIME_VALID, | ||
.name = "IDLE", | ||
.desc = "ARM clock gating(WFI)", | ||
}, | ||
}; | ||
|
||
static DEFINE_PER_CPU(struct cpuidle_device, exynos4_cpuidle_device); | ||
|
||
static struct cpuidle_driver exynos4_idle_driver = { | ||
.name = "exynos4_idle", | ||
.owner = THIS_MODULE, | ||
}; | ||
|
||
static int exynos4_enter_idle(struct cpuidle_device *dev, | ||
struct cpuidle_state *state) | ||
{ | ||
struct timeval before, after; | ||
int idle_time; | ||
|
||
local_irq_disable(); | ||
do_gettimeofday(&before); | ||
|
||
cpu_do_idle(); | ||
|
||
do_gettimeofday(&after); | ||
local_irq_enable(); | ||
idle_time = (after.tv_sec - before.tv_sec) * USEC_PER_SEC + | ||
(after.tv_usec - before.tv_usec); | ||
|
||
return idle_time; | ||
} | ||
|
||
static int __init exynos4_init_cpuidle(void) | ||
{ | ||
int i, max_cpuidle_state, cpu_id; | ||
struct cpuidle_device *device; | ||
|
||
cpuidle_register_driver(&exynos4_idle_driver); | ||
|
||
for_each_cpu(cpu_id, cpu_online_mask) { | ||
device = &per_cpu(exynos4_cpuidle_device, cpu_id); | ||
device->cpu = cpu_id; | ||
|
||
device->state_count = (sizeof(exynos4_cpuidle_set) / | ||
sizeof(struct cpuidle_state)); | ||
|
||
max_cpuidle_state = device->state_count; | ||
|
||
for (i = 0; i < max_cpuidle_state; i++) { | ||
memcpy(&device->states[i], &exynos4_cpuidle_set[i], | ||
sizeof(struct cpuidle_state)); | ||
} | ||
|
||
if (cpuidle_register_device(device)) { | ||
printk(KERN_ERR "CPUidle register device failed\n,"); | ||
return -EIO; | ||
} | ||
} | ||
return 0; | ||
} | ||
device_initcall(exynos4_init_cpuidle); |