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/sh/cpu/sh3/watchdog.c

@@ -0,0 +1,27 @@
+/*
+ * (C) Copyright 2010
+ * Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
+ *
+ * (C) Copyright 2007
+ * Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/processor.h>
+#include <asm/system.h>
+
+int watchdog_init(void)
+{
+	return 0;
+}
+
+void reset_cpu(unsigned long ignored)
+{
+	/* Address error with SR.BL=1 first. */
+	trigger_address_error();
+
+	while (1)
+		;
+}