arm64: Juno: Add support for the PCIe host bridge on Juno R1

Juno R1 board sports a functional PCIe host bridge that is
compliant with the SBSA standard found [1] here. With the right
firmware that initialises the XpressRICH3 controller one can
use the generic Host Bridge driver to use the PCIe hardware.

Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>

[1] http://infocenter.arm.com/help/topic/com.arm.doc.den0029a/

arch/arm64/boot/dts/arm/juno-r1.dts

@@ -109,6 +109,26 @@
 
 	#include "juno-base.dtsi"
 
+	pcie-controller@40000000 {
+		compatible = "arm,juno-r1-pcie", "plda,xpressrich3-axi", "pci-host-ecam-generic";
+		device_type = "pci";
+		reg = <0 0x40000000 0 0x10000000>;	/* ECAM config space */
+		bus-range = <0 255>;
+		linux,pci-domain = <0>;
+		#address-cells = <3>;
+		#size-cells = <2>;
+		dma-coherent;
+		ranges = <0x01000000 0x00 0x5f800000 0x00 0x5f800000 0x0 0x00800000>,
+			 <0x02000000 0x00 0x50000000 0x00 0x50000000 0x0 0x08000000>,
+			 <0x42000000 0x40 0x00000000 0x40 0x00000000 0x1 0x00000000>;
+		#interrupt-cells = <1>;
+		interrupt-map-mask = <0 0 0 7>;
+		interrupt-map = <0 0 0 1 &gic 0 0 0 136 4>,
+				<0 0 0 2 &gic 0 0 0 137 4>,
+				<0 0 0 3 &gic 0 0 0 138 4>,
+				<0 0 0 4 &gic 0 0 0 139 4>;
+		msi-parent = <&v2m_0>;
+	};
 };
 
 &memtimer {