avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/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>;
+};