arm64: add APM X-Gene SoC RTC DTS entry

This patch adds APM X-Gene SoC RTC DTS entry
Signed-off-by: NRameshwar Prasad Sahu <rsahu@apm.com>
Signed-off-by: NLoc Ho <lho@apm.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/arm64/boot/dts/apm-storm.dtsi

@@ -257,6 +257,19 @@
 				enable-offset = <0x0>;
 				enable-mask = <0x39>;
 			};
+
+			rtcclk: rtcclk@17000000 {
+				compatible = "apm,xgene-device-clock";
+				#clock-cells = <1>;
+				clocks = <&socplldiv2 0>;
+				reg = <0x0 0x17000000 0x0 0x2000>;
+				reg-names = "csr-reg";
+				csr-offset = <0xc>;
+				csr-mask = <0x2>;
+				enable-offset = <0x10>;
+				enable-mask = <0x2>;
+				clock-output-names = "rtcclk";
+			};
 		};
 
 		serial0: serial@1c020000 {
@@ -342,5 +355,13 @@
 			phys = <&phy3 0>;
 			phy-names = "sata-phy";
 		};
+
+		rtc: rtc@10510000 {
+			compatible = "apm,xgene-rtc";
+			reg = <0x0 0x10510000 0x0 0x400>;
+			interrupts = <0x0 0x46 0x4>;
+			#clock-cells = <1>;
+			clocks = <&rtcclk 0>;
+		};
 	};
 };