1 files changed, 74 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/cpuidle.c b/arch/arm/mach-at91/cpuidle.c
new file mode 100644
index 00000000..ece1f9ae
--- /dev/null
+++ b/arch/arm/mach-at91/cpuidle.c
@@ -0,0 +1,74 @@
+/*
+ * 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 "pm.h"
+
+#define AT91_MAX_STATES	2
+
+static DEFINE_PER_CPU(struct cpuidle_device, at91_cpuidle_device);
+
+/* 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)
+{
+	at91_standby();
+
+	return index;
+}
+
+static struct cpuidle_driver at91_idle_driver = {
+	.name			= "at91_idle",
+	.owner			= THIS_MODULE,
+	.en_core_tk_irqen	= 1,
+	.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 at91_init_cpuidle(void)
+{
+	struct cpuidle_device *device;
+
+	device = &per_cpu(at91_cpuidle_device, smp_processor_id());
+	device->state_count = AT91_MAX_STATES;
+
+	cpuidle_register_driver(&at91_idle_driver);
+
+	if (cpuidle_register_device(device)) {
+		printk(KERN_ERR "at91_init_cpuidle: Failed registering\n");
+		return -EIO;
+	}
+	return 0;
+}
+
+device_initcall(at91_init_cpuidle);