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Diffstat (limited to 'arch/arm/mach-at91/cpuidle.c')
-rw-r--r--arch/arm/mach-at91/cpuidle.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/cpuidle.c b/arch/arm/mach-at91/cpuidle.c
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+++ b/arch/arm/mach-at91/cpuidle.c
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+/*
+ * based on arch/arm/mach-kirkwood/cpuidle.c
+ *
+ * CPU idle support for AT91 SoC
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * The cpu idle uses wait-for-interrupt and RAM self refresh in order
+ * to implement two idle states -
+ * #1 wait-for-interrupt
+ * #2 wait-for-interrupt and RAM self refresh
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/cpuidle.h>
+#include <linux/io.h>
+#include <linux/export.h>
+#include <asm/proc-fns.h>
+#include <asm/cpuidle.h>
+#include <mach/cpu.h>
+
+#include "pm.h"
+
+#define AT91_MAX_STATES 2
+
+/* Actual code that puts the SoC in different idle states */
+static int at91_enter_idle(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ if (cpu_is_at91rm9200())
+ at91rm9200_standby();
+ else if (cpu_is_at91sam9g45())
+ at91sam9g45_standby();
+ else if (cpu_is_at91sam9263())
+ at91sam9263_standby();
+ else
+ at91sam9_standby();
+
+ return index;
+}
+
+static struct cpuidle_driver at91_idle_driver = {
+ .name = "at91_idle",
+ .owner = THIS_MODULE,
+ .states[0] = ARM_CPUIDLE_WFI_STATE,
+ .states[1] = {
+ .enter = at91_enter_idle,
+ .exit_latency = 10,
+ .target_residency = 100000,
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .name = "RAM_SR",
+ .desc = "WFI and DDR Self Refresh",
+ },
+ .state_count = AT91_MAX_STATES,
+};
+
+/* Initialize CPU idle by registering the idle states */
+static int __init at91_init_cpuidle(void)
+{
+ return cpuidle_register(&at91_idle_driver, NULL);
+}
+
+device_initcall(at91_init_cpuidle);