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/mach-bcm283x/phys2bus.c

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2015 Stephen Warren
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <config.h>
+#include <phys2bus.h>
+
+unsigned long phys_to_bus(unsigned long phys)
+{
+#ifndef CONFIG_BCM2835
+	return 0xc0000000 | phys;
+#else
+	return 0x40000000 | phys;
+#endif
+}
+
+unsigned long bus_to_phys(unsigned long bus)
+{
+	return bus & ~0xc0000000;
+}