board: samsung: add initial Espresso7420 board support

Espresso7420 is a development/evaluation board for Exynos7420 SoC. It
includes multiple onboard compoments (EMMC/Codec) and various
interconnects (USB/HDMI).

Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/arch/arm/dts/exynos7420-espresso7420.dts b/arch/arm/dts/exynos7420-espresso7420.dts
new file mode 100644
index 0000000..f17a848
--- /dev/null
+++ b/arch/arm/dts/exynos7420-espresso7420.dts
@@ -0,0 +1,24 @@
+/*
+ * Samsung Espresso7420 board device tree source
+ *
+ * Copyright (c) 2016 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include "exynos7420.dtsi"
+/ {
+	model = "Samsung Espresso7420 board based on Exynos7420";
+	compatible = "samsung,espresso7420", "samsung,exynos7420";
+
+	aliases {
+		serial2 = "/serial@14C30000";
+		console = "/serial@14C30000";
+		pinctrl0 = "/pinctrl@13470000";
+	};
+};
+
+&fin_pll {
+	clock-frequency = <24000000>;
+};