arm64: tegra: Add CPU idle states properties for Tegra210

Add idle states properties for generic ARM CPU idle driver. This
includes a cpu-sleep state which is the power down state of CPU cores.
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra210.dtsi

@@ -1371,24 +1371,43 @@ cpu@0 {
 				 <&dfll>;
 			clock-names = "cpu_g", "pll_x", "pll_p", "dfll";
 			clock-latency = <300000>;
+			cpu-idle-states = <&CPU_SLEEP>;
 		};
 
 		cpu@1 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a57";
 			reg = <1>;
+			cpu-idle-states = <&CPU_SLEEP>;
 		};
 
 		cpu@2 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a57";
 			reg = <2>;
+			cpu-idle-states = <&CPU_SLEEP>;
 		};
 
 		cpu@3 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a57";
 			reg = <3>;
+			cpu-idle-states = <&CPU_SLEEP>;
+		};
+
+		idle-states {
+			entry-method = "psci";
+
+			CPU_SLEEP: cpu-sleep {
+				compatible = "arm,idle-state";
+				arm,psci-suspend-param = <0x40000007>;
+				entry-latency-us = <100>;
+				exit-latency-us = <30>;
+				min-residency-us = <1000>;
+				wakeup-latency-us = <130>;
+				idle-state-name = "cpu-sleep";
+				status = "disabled";
+			};
 		};
 	};