arm64: add support for ACPI Low Power Idle(LPI)

This patch adds appropriate callbacks to support ACPI Low Power Idle
(LPI) on ARM64.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c
index 06786fdaadeb..75a0f8acef66 100644
--- a/arch/arm64/kernel/cpuidle.c
+++ b/arch/arm64/kernel/cpuidle.c
@@ -9,6 +9,9 @@
  * 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>
 
@@ -39,3 +42,18 @@ int arm_cpuidle_suspend(int index)
 
         return cpu_ops[cpu]->cpu_suspend(index);
 }
+
+#ifdef CONFIG_ACPI
+
+#include <acpi/processor.h>
+
+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)
+{
+        return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, lpi->index);
+}
+#endif