arm: dts: agilex: Add base dtsi and devkit dts

Add device tree files for Agilex SoC platform.

socfpga_agilex-u-boot.dtsi and socfpga_agilex_socdk-u-boot.dts contains
Uboot specific DT properties.

socfpga_agilex.dtsi and socfpga_agilex_socdk.dts are from Linux
(kernel/git/dinguyen/linux.git, commit 6f0bf971bacacc)

Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
Reviewed-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
diff --git a/arch/arm/dts/socfpga_agilex_socdk-u-boot.dtsi b/arch/arm/dts/socfpga_agilex_socdk-u-boot.dtsi
new file mode 100644
index 0000000..1908be4
--- /dev/null
+++ b/arch/arm/dts/socfpga_agilex_socdk-u-boot.dtsi
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * U-Boot additions
+ *
+ * Copyright (C) 2019 Intel Corporation <www.intel.com>
+ */
+
+#include "socfpga_agilex-u-boot.dtsi"
+
+/{
+	aliases {
+		spi0 = &qspi;
+		i2c0 = &i2c1;
+	};
+
+	memory {
+		/* 8GB */
+		reg = <0 0x00000000 0 0x80000000>,
+		      <2 0x80000000 1 0x80000000>;
+	};
+};
+
+&flash0 {
+	compatible = "jedec,spi-nor";
+	spi-tx-bus-width = <4>;
+	spi-rx-bus-width = <4>;
+	u-boot,dm-pre-reloc;
+};
+
+&i2c1 {
+	status = "okay";
+};
+
+&mmc {
+	drvsel = <3>;
+	smplsel = <0>;
+	u-boot,dm-pre-reloc;
+};
+