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/mips/include/asm/sgidefs.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 1996, 1999, 2001 Ralf Baechle
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Copyright (C) 2001 MIPS Technologies, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ */
+#ifndef __ASM_SGIDEFS_H
+#define __ASM_SGIDEFS_H
+
+/*
+ * Using a Linux compiler for building Linux seems logic but not to
+ * everybody.
+ */
+#if 0 /* ndef __linux__ */
+#error Use a Linux compiler or give up.
+#endif
+
+/*
+ * Definitions for the ISA levels
+ *
+ * With the introduction of MIPS32 / MIPS64 instruction sets definitions
+ * MIPS ISAs are no longer subsets of each other.  Therefore comparisons
+ * on these symbols except with == may result in unexpected results and
+ * are forbidden!
+ */
+#define _MIPS_ISA_MIPS1		1
+#define _MIPS_ISA_MIPS2		2
+#define _MIPS_ISA_MIPS3		3
+#define _MIPS_ISA_MIPS4		4
+#define _MIPS_ISA_MIPS5		5
+#define _MIPS_ISA_MIPS32	6
+#define _MIPS_ISA_MIPS64	7
+
+/*
+ * Subprogram calling convention
+ */
+#define _MIPS_SIM_ABI32		1
+#define _MIPS_SIM_NABI32	2
+#define _MIPS_SIM_ABI64		3
+
+#endif /* __ASM_SGIDEFS_H */