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/include/linux/crc8.h

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2013 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+
+#ifndef __linux_crc8_h
+#define __linux_crc8_h
+
+/**
+ * crc8() - Calculate and return CRC-8 of the data
+ *
+ * This uses an x^8 + x^2 + x + 1 polynomial.  A table-based algorithm would
+ * be faster, but for only a few bytes it isn't worth the code size
+ *
+ * @crc_start: CRC8 start value
+ * @vptr: Buffer to checksum
+ * @len: Length of buffer in bytes
+ * @return CRC8 checksum
+ */
+unsigned int crc8(unsigned int crc_start, const unsigned char *vptr, int len);
+
+#endif