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Diffstat (limited to 'arch/arm/mach-s3c64xx/cpuidle.c')
-rw-r--r--arch/arm/mach-s3c64xx/cpuidle.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c64xx/cpuidle.c b/arch/arm/mach-s3c64xx/cpuidle.c
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+++ b/arch/arm/mach-s3c64xx/cpuidle.c
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+/* linux/arch/arm/mach-s3c64xx/cpuidle.c
+ *
+ * Copyright (c) 2011 Wolfson Microelectronics, plc
+ * 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 <linux/export.h>
+#include <linux/time.h>
+
+#include <asm/proc-fns.h>
+
+#include <mach/map.h>
+
+#include <mach/regs-sys.h>
+#include <mach/regs-syscon-power.h>
+
+static int s3c64xx_enter_idle(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ struct timeval before, after;
+ unsigned long tmp;
+ int idle_time;
+
+ local_irq_disable();
+ do_gettimeofday(&before);
+
+ /* Setup PWRCFG to enter idle mode */
+ tmp = __raw_readl(S3C64XX_PWR_CFG);
+ tmp &= ~S3C64XX_PWRCFG_CFG_WFI_MASK;
+ tmp |= S3C64XX_PWRCFG_CFG_WFI_IDLE;
+ __raw_writel(tmp, S3C64XX_PWR_CFG);
+
+ 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);
+
+ dev->last_residency = idle_time;
+ return index;
+}
+
+static struct cpuidle_state s3c64xx_cpuidle_set[] = {
+ [0] = {
+ .enter = s3c64xx_enter_idle,
+ .exit_latency = 1,
+ .target_residency = 1,
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .name = "IDLE",
+ .desc = "System active, ARM gated",
+ },
+};
+
+static struct cpuidle_driver s3c64xx_cpuidle_driver = {
+ .name = "s3c64xx_cpuidle",
+ .owner = THIS_MODULE,
+ .state_count = ARRAY_SIZE(s3c64xx_cpuidle_set),
+};
+
+static struct cpuidle_device s3c64xx_cpuidle_device = {
+ .state_count = ARRAY_SIZE(s3c64xx_cpuidle_set),
+};
+
+static int __init s3c64xx_init_cpuidle(void)
+{
+ int ret;
+
+ memcpy(s3c64xx_cpuidle_driver.states, s3c64xx_cpuidle_set,
+ sizeof(s3c64xx_cpuidle_set));
+ cpuidle_register_driver(&s3c64xx_cpuidle_driver);
+
+ ret = cpuidle_register_device(&s3c64xx_cpuidle_device);
+ if (ret) {
+ pr_err("Failed to register cpuidle device: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+device_initcall(s3c64xx_init_cpuidle);