tiny4412裸板程序之点灯（二）

上一篇博文中我们已经编译出了裸板程序led.bin

接着就是制作sd卡启动，将裸板程序跑起来。

首先需要将sdcard插入PC，让ubuntu系统识别到sdcard，目前来说没有windows工具，因此只能使用真实的linux机器或者虚拟机。

sc@sc-System-Product-Name:~/work/tiny4412/sd_fuse$ df
Filesystem      1K-blocks      Used  Available Use% Mounted on
udev              3990428         0    3990428   0% /dev
tmpfs              803368      9980     793388   2% /run
/dev/sda4        98299524   6071976   87211180   7% /
tmpfs             4016832       216    4016616   1% /dev/shm
tmpfs                5120         4       5116   1% /run/lock
tmpfs             4016832         0    4016832   0% /sys/fs/cgroup
/dev/sda2         7743632    147204    7180020   3% /boot
/dev/sda1          997456      3492     993964   1% /boot/efi
/dev/sda5      1807565100 161443956 1554279096  10% /home
tmpfs              803368        56     803312   1% /run/user/1000
/dev/sdb1         7590912         4    7590908   1% /media/sc/FRIENDLYARM

上面的/dev/sdb1就是我们的sdcard设备。

接着在友善之臂提供的uboot文件目录下有个sd_fuse文件夹，里面是打包脚本、源文件和一些工具。我们就 是利用这里面的文件和工具制作卡启动的。

其中V310-EVT1-mkbl2.c是让我们编译mkbl2工具的。需要执行gcc -o  mkbl2  V310-EVT1-mkbl2.c，编译出mkbl2工具，这个工具在tiny4412/sd_fusing.sh 脚本中会被调用到。

tiny4412文件夹下有如下文件

其中E4412_N.bl1.bin （BL1）是由三星原厂提供，没有源码。

E4412_tzsw.bin也是由三星原厂提供的。

sd_fusing.sh就是要使用是烧写脚本。

在tiny4412目录下执行  sudo ./sd_fusing.sh /dev/sdb ../led.bin    // (led.bin拷贝到了，tiny4412的上级目录下。/dev/sdb是ubuntu识别到的我们的sdcard)

报错： Usage: unsupported size

这里主要是在执行mkbl2文件的时候出错，在sd_fuse.sh文件中调用到了mkbl2

即执行了./mkbl2 led.bin bl2.bin 14336后出错。

查看mkbl2的源码V310-EVT1-mkbl2.c

/*
 * 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 
#include 
#include 

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    \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;
}

它做的主要工作是：

1.从源文件中读取13k的数据到buf中，

2.处理buf中的前14332字节的数据，得到4字节的checksum

3.组装buf中的钱14332字节的数据和4字节的checksum，得到一个新的14k的buf数据。

4.将3中构建的buf数据写到bl2.bin文件中。

问题是当我们的源文件小于14k时，就直接返回错误了，因此我们需要修改源文件，让其支持小于14k的文件。

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 
#include 
#include 
 
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    \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;
}

这样就不在报错了。也正常生成bl2.bin文件。

接着还需要修改sd_fusing.sh

#
# Copyright (C) 2011 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.
#
####################################

if [ -z $1 ]
then
    echo "usage: ./sd_fusing.sh "
    exit 0
fi

if [ -b $1 ]
then
    echo "$1 reader is identified."
else
    echo "$1 is NOT identified."
    exit 0
fi

####################################
#

BDEV_NAME=`basename $1`
BDEV_SIZE=`cat /sys/block/${BDEV_NAME}/size`

if [ ${BDEV_SIZE} -le 0 ]; then
	echo "Error: NO media found in card reader."
	exit 1
fi

if [ ${BDEV_SIZE} -gt 32000000 ]; then
	echo "Error: Block device size (${BDEV_SIZE}) is too large"
	exit 1
fi

####################################
# check files

#E4412_UBOOT=../../u-boot.bin  //原文件中是直接指定了u-boot.bin文件，
E4412_UBOOT=$2                 //需要修改成传入的第二个参数，也就是led.bin 
MKBL2=../mkbl2

if [ ! -f ${E4412_UBOOT} ]; then
	echo "Error: u-boot.bin NOT found, please build it & try again."
	exit -1
fi

if [ ! -f ${MKBL2} ]; then
	echo "Error: can not find host tool - mkbl2, stop."
	exit -1
fi

#
${MKBL2} ${E4412_UBOOT} bl2.bin 14336

####################################
# fusing images

signed_bl1_position=1
bl2_position=17
uboot_position=49
tzsw_position=705

#
echo "---------------------------------------"
echo "BL1 fusing"
dd iflag=dsync oflag=dsync if=./E4412_N.bl1.bin of=$1 seek=$signed_bl1_position

#
echo "---------------------------------------"
echo "BL2 fusing"
dd iflag=dsync oflag=dsync if=./bl2.bin of=$1 seek=$bl2_position

#
echo "---------------------------------------"
echo "u-boot fusing"
dd iflag=dsync oflag=dsync if=${E4412_UBOOT} of=$1 seek=$uboot_position

#
echo "---------------------------------------"
echo "TrustZone S/W fusing"
dd iflag=dsync oflag=dsync if=./E4412_tzsw.bin of=$1 seek=$tzsw_position

#
sync

####################################
#
echo "---------------------------------------"
echo "U-boot image is fused successfully."
echo "Eject SD card and insert it again."

如果想看sd_fusing.sh的代码注释可以参考：https://blog.csdn.net/z961968549/article/details/78041839 写的很详细。

现在准备工作完成：

插上sdcard，执行：

sc@sc-System-Product-Name:~/work/tiny4412/sd_fuse/tiny4412$ sudo ./sd_fusing.sh /dev/sdb ../led.bin 
/dev/sdb reader is identified.
---------------------------------------
BL1 fusing
16+0 records in
16+0 records out
8192 bytes (8.2 kB, 8.0 KiB) copied, 0.0271815 s, 301 kB/s
---------------------------------------
BL2 fusing
28+0 records in
28+0 records out
14336 bytes (14 kB, 14 KiB) copied, 0.0450742 s, 318 kB/s
---------------------------------------
u-boot fusing
0+1 records in
0+1 records out
176 bytes copied, 0.00129791 s, 136 kB/s
---------------------------------------
TrustZone S/W fusing
184+0 records in
184+0 records out
94208 bytes (94 kB, 92 KiB) copied, 0.287752 s, 327 kB/s
---------------------------------------
U-boot image is fused successfully.
Eject SD card and insert it again.

这样就烧写成功。

将sdcard插入开发板，把启动开关拨到sdcard启动，复位系统，就可以看到led灯轮流亮起。