powerpc: dts: p2020: Define L2 cache node

Copy definition of L2 cache node from upstream Linux kernel P2020 dts files.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/arch/powerpc/dts/p2020-post.dtsi b/arch/powerpc/dts/p2020-post.dtsi
index 0a296cf..1c3f787 100644
--- a/arch/powerpc/dts/p2020-post.dtsi
+++ b/arch/powerpc/dts/p2020-post.dtsi
@@ -56,6 +56,14 @@
 /include/ "pq3-duart-0.dtsi"
 /include/ "pq3-gpio-0.dtsi"
 
+	L2: l2-cache-controller@20000 {
+		compatible = "fsl,p2020-l2-cache-controller";
+		reg = <0x20000 0x1000>;
+		cache-line-size = <32>; /* 32 bytes */
+		cache-size = <0x80000>; /* L2,512K */
+		interrupts = <16 2 0 0>;
+	};
+
 /include/ "pq3-etsec1-0.dtsi"
 /include/ "pq3-etsec1-timer-0.dtsi"