mkbl2:Usage: unsupported size

最新推荐文章于 2024-09-20 21:13:34 发布

原创最新推荐文章于 2024-09-20 21:13:34 发布 · 1.8k 阅读

1 ·

CC 4.0 BY-SA版权

文章标签：

#mkbl2 #bl2.bin #unsupported size

Tiny4412 专栏收录该内容

22 篇文章

订阅专栏

本文介绍如何解决使用mkbl2工具时遇到的问题，详细分析了错误原因并提供了修改后的源码，确保生成的BL2.bin文件符合要求。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

在前面的文章 tiny4412 led 裸机程序中遇到一个问题，使用 mkbl2 来将裸机程序制作成 BL2.bin 时报错。
./mkbl2 led.bin bl2.bin 14336
Usage: unsupported size
我尝试把 14336 改成 led.bin 文件的实际大小后，烧写到 emmc 程序无法按照预期执行。那么问题出在哪？

BL2 位于设备偏移地址(512 +8K)字节处，BL1从这个位置读入 14K 字节的数据，存在iRAM 地址 0x02023400 处。 BL2不能大于(14K – 4)字节，最后 4字节用于存放较验码。

那么我猜测，当我们的 led.bin 小于 14K 的时候，我们生成的 bl2.bin 也得是14K大小，并且最后4字节是校验码。

来看看 mkbl2 的源码：

/*
 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
 *              http://www.samsung.com/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int main (int argc, char *argv[])
{
	FILE		*fp;
	unsigned char	src;
	char		*Buf, *a;
	int		BufLen;
	int		nbytes, fileLen;
	unsigned int	checksum = 0;
	int		i;

	if (argc != 4)
	{
		printf("Usage: mkbl1 <source file> <destination file> <size> \n");
		return -1;
	}

	BufLen = atoi(argv[3]);
	Buf = (char *)malloc(BufLen);
	memset(Buf, 0x00, BufLen);

	fp = fopen(argv[1], "rb");
	if( fp == NULL)
	{
		printf("source file open error\n");
		free(Buf);
		return -1;
	}

	fseek(fp, 0L, SEEK_END);
	fileLen = ftell(fp);
	fseek(fp, 0L, SEEK_SET);

	if ( BufLen > fileLen )
	{
		printf("Usage: unsupported size\n");
		free(Buf);
		fclose(fp);
		return -1;
	}

	nbytes = fread(Buf, 1, BufLen, fp);

	if ( nbytes != BufLen )
	{
		printf("source file read error\n");
		free(Buf);
		fclose(fp);
		return -1;
	}

	fclose(fp);

	for(i = 0;i < (14 * 1024) - 4;i++)
	{
		checksum += (unsigned char)(Buf[i]);
	}
	*(unsigned int*)(Buf+i) = checksum;

	fp = fopen(argv[2], "wb");
	if (fp == NULL)
	{
		printf("destination file open error\n");
		free(Buf);
		return -1;
	}

	a	= Buf;
	nbytes	= fwrite( a, 1, BufLen, fp);

	if ( nbytes != BufLen )
	{
		printf("destination file write error\n");
		free(Buf);
		fclose(fp);
		return -1;
	}

	free(Buf);
	fclose(fp);

	return 0;
}

代码很简单，问题很明显，当我们的 Led.bin 小于14K时，我们输入文件实际大小，Bufsize == filesize ，但是它在计算校验的时候居然是按照 14k 的大小来计算的，数组都溢出了！！！

修改：

/*
 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
 *              http://www.samsung.com/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int main (int argc, char *argv[])
{
	FILE		*fp;
	unsigned char	src;
	char		*Buf, *a;
	int		BufLen;
	int		nbytes, fileLen;
	unsigned int	checksum = 0;
	int		i;

	if (argc != 4)
	{
		printf("Usage: mkbl1 <source file> <destination file> <size> \n");
		return -1;
	}

	BufLen = atoi(argv[3]);
	Buf = (char *)malloc(BufLen);
	memset(Buf, 0x00, BufLen);

	fp = fopen(argv[1], "rb");
	if( fp == NULL)
	{
		printf("source file open error\n");
		free(Buf);
		return -1;
	}

	fseek(fp, 0L, SEEK_END);
	fileLen = ftell(fp);
	fseek(fp, 0L, SEEK_SET);
/*
	if ( BufLen > fileLen )
	{
		printf("Usage: unsupported size\n");
		free(Buf);
		fclose(fp);
		return -1;
	}
*/
	//nbytes = fread(Buf, 1, BufLen, fp);
	if(BufLen > fileLen)
		nbytes = fread(Buf, 1, fileLen, fp);
	else
		nbytes = fread(Buf, 1, BufLen, fp);
/*
	if ( nbytes != BufLen )
	{
		printf("source file read error\n");
		free(Buf);
		fclose(fp);
		return -1;
	}
*/
	fclose(fp);

	for(i = 0;i < (14 * 1024) - 4;i++)
	{
		checksum += (unsigned char)(Buf[i]);
	}
	*(unsigned int*)(Buf+i) = checksum;

	fp = fopen(argv[2], "wb");
	if (fp == NULL)
	{
		printf("destination file open error\n");
		free(Buf);
		return -1;
	}

	a	= Buf;
	nbytes	= fwrite( a, 1, BufLen, fp);

	if ( nbytes != BufLen )
	{
		printf("destination file write error\n");
		free(Buf);
		fclose(fp);
		return -1;
	}

	free(Buf);
	fclose(fp);

	return 0;
}