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/board/samsung/smdkv310/tools/mksmdkv310spl.c

@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2011 Samsung Electronics
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#define CHECKSUM_OFFSET		(14*1024-4)
+#define BUFSIZE			(16*1024)
+#define FILE_PERM		(S_IRUSR | S_IWUSR | S_IRGRP \
+				| S_IWGRP | S_IROTH | S_IWOTH)
+/*
+* Requirement:
+* IROM code reads first 14K bytes from boot device.
+* It then calculates the checksum of 14K-4 bytes and compare with data at
+* 14K-4 offset.
+*
+* This function takes two filenames:
+* IN  "u-boot-spl.bin" and
+* OUT "u-boot-mmc-spl.bin" as filenames.
+* It reads the "u-boot-spl.bin" in 16K buffer.
+* It calculates checksum of 14K-4 Bytes and stores at 14K-4 offset in buffer.
+* It writes the buffer to "u-boot-mmc-spl.bin" file.
+*/
+
+int main(int argc, char **argv)
+{
+	int i, len;
+	unsigned char buffer[BUFSIZE] = {0};
+	int ifd, ofd;
+	unsigned int checksum = 0, count;
+
+	if (argc != 3) {
+		printf(" %d Wrong number of arguments\n", argc);
+		exit(EXIT_FAILURE);
+	}
+
+	ifd = open(argv[1], O_RDONLY);
+	if (ifd < 0) {
+		fprintf(stderr, "%s: Can't open %s: %s\n",
+			argv[0], argv[1], strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	ofd = open(argv[2], O_WRONLY | O_CREAT | O_TRUNC, FILE_PERM);
+	if (ofd < 0) {
+		fprintf(stderr, "%s: Can't open %s: %s\n",
+			argv[0], argv[2], strerror(errno));
+		if (ifd)
+			close(ifd);
+		exit(EXIT_FAILURE);
+	}
+
+	len = lseek(ifd, 0, SEEK_END);
+	lseek(ifd, 0, SEEK_SET);
+
+	count = (len < CHECKSUM_OFFSET) ? len : CHECKSUM_OFFSET;
+
+	if (read(ifd, buffer, count) != count) {
+		fprintf(stderr, "%s: Can't read %s: %s\n",
+			argv[0], argv[1], strerror(errno));
+
+		if (ifd)
+			close(ifd);
+		if (ofd)
+			close(ofd);
+
+		exit(EXIT_FAILURE);
+	}
+
+	for (i = 0, checksum = 0; i < CHECKSUM_OFFSET; i++)
+		checksum += buffer[i];
+
+	memcpy(&buffer[CHECKSUM_OFFSET], &checksum, sizeof(checksum));
+
+	if (write(ofd, buffer, BUFSIZE) != BUFSIZE) {
+		fprintf(stderr, "%s: Can't write %s: %s\n",
+			argv[0], argv[2], strerror(errno));
+
+		if (ifd)
+			close(ifd);
+		if (ofd)
+			close(ofd);
+
+		exit(EXIT_FAILURE);
+	}
+
+	if (ifd)
+		close(ifd);
+	if (ofd)
+		close(ofd);
+
+	return EXIT_SUCCESS;
+}