1 files changed, 65 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c
new file mode 100644
index 000000000..f2d13810d
--- /dev/null
+++ b/arch/arm64/kernel/cpuidle.c
@@ -0,0 +1,65 @@
+/*
+ * ARM64 CPU idle arch support
+ *
+ * Copyright (C) 2014 ARM Ltd.
+ * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.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/acpi.h>
+#include <linux/cpuidle.h>
+#include <linux/cpu_pm.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include <asm/cpuidle.h>
+#include <asm/cpu_ops.h>
+
+int arm_cpuidle_init(unsigned int cpu)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_suspend &&
+			cpu_ops[cpu]->cpu_init_idle)
+		ret = cpu_ops[cpu]->cpu_init_idle(cpu);
+
+	return ret;
+}
+
+/**
+ * arm_cpuidle_suspend() - function to enter a low-power idle state
+ * @arg: argument to pass to CPU suspend operations
+ *
+ * Return: 0 on success, -EOPNOTSUPP if CPU suspend hook not initialized, CPU
+ * operations back-end error code otherwise.
+ */
+int arm_cpuidle_suspend(int index)
+{
+	int cpu = smp_processor_id();
+
+	return cpu_ops[cpu]->cpu_suspend(index);
+}
+
+#ifdef CONFIG_ACPI
+
+#include <acpi/processor.h>
+
+#define ARM64_LPI_IS_RETENTION_STATE(arch_flags) (!(arch_flags))
+
+int acpi_processor_ffh_lpi_probe(unsigned int cpu)
+{
+	return arm_cpuidle_init(cpu);
+}
+
+int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)
+{
+	if (ARM64_LPI_IS_RETENTION_STATE(lpi->arch_flags))
+		return CPU_PM_CPU_IDLE_ENTER_RETENTION(arm_cpuidle_suspend,
+						lpi->index);
+	else
+		return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, lpi->index);
+}
+#endif