……
static void print_one_part (dos_partition_t *p, int ext_part_sector, int part_num)
{ //打印一个分区信息
……
printf ("%5d/t/t%10d/t%10d/t%2x%s/n",
part_num, lba_start, lba_size, p->sys_ind,
(is_extended (p->sys_ind) ? " Extd" : ""));
}
static int test_block_type(unsigned char *buffer)
{ //测试块类型
if((buffer[DOS_PART_MAGIC_OFFSET + 0] != 0x55) ||
(buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) ) {
return (-1);
} //不是dos块
if(strncmp(&buffer[DOS_PBR_FSTYPE_OFFSET],"FAT",3)==0)
return DOS_PBR;
return DOS_MBR;
}
int test_part_dos (block_dev_desc_t *dev_desc)
{ //测试是否为dos块
unsigned char buffer[DEFAULT_SECTOR_SIZE];
if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *) buffer) != 1) ||
(buffer[DOS_PART_MAGIC_OFFSET + 0] != 0x55) ||
(buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) ) {
return (-1);
}
return (0);
}
static void print_partition_extended (block_dev_desc_t *dev_desc, int ext_part_sector, int relative, int part_num)
{ //输出与其扩展分区表有关的分区信息
……
//输出所有主要/逻辑分区
pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
for (i = 0; i < 4; i++, pt++) {//文件系统不显示MBR以外的分区
if ((pt->sys_ind != 0) &&
(ext_part_sector == 0 || !is_extended (pt->sys_ind)) ) {
print_one_part (pt, ext_part_sector, part_num);
}
if ((ext_part_sector == 0) ||
(pt->sys_ind != 0 && !is_extended (pt->sys_ind)) ) {
part_num++;
}
}
//处理扩展分区
pt = (dos_partition_t *) (buffer + DOS_PART_TBL_OFFSET);
for (i = 0; i < 4; i++, pt++) {
if (is_extended (pt->sys_ind)) {
int lba_start = le32_to_int (pt->start4) + relative;
print_partition_extended (dev_desc, lba_start,
ext_part_sector == 0 ? lba_start
: relative,
part_num);
}
}
return;
}
static int get_partition_info_extended (block_dev_desc_t *dev_desc, int ext_part_sector, int relative, int part_num, int which_part, disk_partition_t *info)
{ //获取与其扩展分区表有关的分区信息
……
}
……
Part_iso.c 文件：int get_partition_info_iso_verb(block_dev_desc_t * dev_desc, int part_num, disk_partition_t * info, int verb)
{ //获得iso设备块的分区信息
……
//第一部分必须是主要卷
blkaddr=PVD_OFFSET;
if (dev_desc->block_read (dev_desc->dev, PVD_OFFSET, 1, (ulong *) tmpbuf) != 1)
return (-1);
if(ppr->desctype!=0x01) {
if(verb)
printf ("** First descriptor is NOT a primary desc on %d:%d **/n",
dev_desc->dev, part_num);
return (-1);
}
if(strncmp(ppr->stand_ident,"CD001",5)!=0) {
if(verb)
printf ("** Wrong ISO Ident: %s on %d:%d **/n",
ppr->stand_ident,dev_desc->dev, part_num);
return (-1);
}
……
//寻找入口
if(strncmp(pbr->ident_str,"EL TORITO SPECIFICATION",23)!=0) {
if(verb)
printf ("** Wrong El Torito ident: %s on %d:%d **/n",
pbr->ident_str,dev_desc->dev, part_num);
return (-1);
}
bootaddr=le32_to_int(pbr->pointer);
PRINTF(" Boot Entry at: %08lX/n",bootaddr);
if (dev_desc->block_read (dev_desc->dev, bootaddr, 1, (ulong *) tmpbuf) != 1) {
if(verb)
printf ("** Can't read Boot Entry at %lX on %d:%d **/n",
bootaddr,dev_desc->dev, part_num);
return (-1);
}
……
//找到有效入口，现在寻找分区
entry_num=0;
offset=0x20;
sprintf (info->type, "U-Boot");
switch(dev_desc->if_type) {
case IF_TYPE_IDE:
case IF_TYPE_ATAPI:
sprintf (info->name, "hd%c%d/n", 'a' + dev_desc->dev, part_num);
break;
……
default:
sprintf (info->name, "xx%c%d/n", 'a' + dev_desc->dev, part_num);
break;
}
//bootcatalog (including validation Entry) 必须小于 2048Bytes
while(offset<2048) {
pide=(iso_init_def_entry_t *)&tmpbuf[offset];
if ((pide->boot_ind==0x88) ||
(pide->boot_ind==0x00)) { //默认入口的id头
if(entry_num==part_num) { //找到分区
goto found;
}
entry_num++; //记录分区入口数
offset+=0x20;
continue;
}
if ((pide->boot_ind==0x90) ||
(pide->boot_ind==0x91) ||
(pide->boot_ind==0x44)) {
offset+=0x20; //跳过不使用的入口
}
else {
if(verb)
printf ("** Partition %d not found on device %d **/n",
part_num,dev_desc->dev);
return(-1);
}
}
……
newblkaddr=le32_to_int(pide->rel_block_addr);
info->start=newblkaddr;
PRINTF(" part %d found @ %lx size %lx/n",part_num,newblkaddr,info->size);
return 0;
}
int get_partition_info_iso(block_dev_desc_t * dev_desc, int part_num, disk_partition_t * info)
{
return(get_partition_info_iso_verb(dev_desc, part_num, info, 1));
}
void print_part_iso(block_dev_desc_t * dev_desc)
{ //打印分区信息
disk_partition_t info;
int i;
if(get_partition_info_iso_verb(dev_desc,0,&info,0)==-1) {
printf("** No boot partition found on device %d **/n",dev_desc->dev);
return;
}
printf("Part Start Sect x Size Type/n");
i=0;
do {
printf (" %2d %8ld %8ld %6ld %.32s/n",
i, info.start, info.size, info.blksz, info.type);
i++;
} while (get_partition_info_iso_verb(dev_desc,i,&info,0)!=-1);
}
int test_part_iso (block_dev_desc_t *dev_desc)
{ 测试是否为iso分区
disk_partition_t info;
return(get_partition_info_iso_verb(dev_desc,0,&info,0));
}
Part_mac.c 文件：int test_part_mac (block_dev_desc_t *dev_desc)
{ //检查是否为有效的mac分区
……
if (part_mac_read_ddb (dev_desc, &ddesc)) {//读块错误，或无有效信息
return (-1); }
n = 1; //假设最少有一个分区
for (i=1; i<=n; ++i) {
if ((dev_desc->block_read(dev_desc->dev, i, 1, (ulong *)&mpart) != 1) ||
(mpart.signature != MAC_PARTITION_MAGIC) ) {
return (-1);
}
n = mpart.map_count; 更新分区数
}
return (0);
}
void print_part_mac (block_dev_desc_t *dev_desc)
{ //输出mac分区信息
……
if (part_mac_read_ddb (dev_desc, &ddesc)) {
return;
}
n = ddesc.blk_count;
……
printf ("Block Size=%d, Number of Blocks=%d, "
"Total Capacity: %ld.%ld MB = %ld.%ld GB/n"
"DeviceType=0x%x, DeviceId=0x%x/n/n"
" #: type name"
" length base (size)/n",
ddesc.blk_size,
ddesc.blk_count,
mb.quot, mb.rem, gb.quot, gb.rem,
ddesc.dev_type, ddesc.dev_id
);
n = 1; //假设最少有一个分区
for (i=1; i<=n; ++i) {
……
printf ("%20.32s %-18.32s %10u @ %-10u (%3ld%c)/n",
mpart.type,
mpart.name,
mpart.block_count,
mpart.start_block,
bytes, c
);
}
return;
}
static int part_mac_read_ddb (block_dev_desc_t *dev_desc, mac_driver_desc_t *ddb_p)
{ //读取设备描述块信息
……
if (ddb_p->signature != MAC_DRIVER_MAGIC) {
#if 0
printf ("** Bad Signature: expected 0x%04x, got 0x%04x/n",
MAC_DRIVER_MAGIC, ddb_p->signature);
#endif
return (-1);
}
return (0);
}
static int part_mac_read_pdb (block_dev_desc_t *dev_desc, int part, mac_partition_t *pdb_p)
{ //读取分区描述块信息
int n = 1;
for (;;) { //必须从第一个分区开始读描述块，只有这样才能知道一共有多少个分区
if (dev_desc->block_read (dev_desc->dev, n, 1, (ulong *)pdb_p) != 1) {
printf ("** Can't read Partition Map on %d:%d **/n",
dev_desc->dev, n);
return (-1);
}
if (pdb_p->signature != MAC_PARTITION_MAGIC) {
printf ("** Bad Signature on %d:%d: "
"expected 0x%04x, got 0x%04x/n",
dev_desc->dev, n, MAC_PARTITION_MAGIC, pdb_p->signature);
return (-1);
}
if (n == part)
return (0);
if ((part < 1) || (part > pdb_p->map_count)) {
printf ("** Invalid partition %d:%d [%d:1...%d:%d only]/n",
dev_desc->dev, part,
dev_desc->dev,
dev_desc->dev, pdb_p->map_count);
return (-1);
}
n = part; //更新分区数
}
}
int get_partition_info_mac (block_dev_desc_t *dev_desc, int part, disk_partition_t *info)
{ //获取mac分区的信息
mac_driver_desc_t ddesc;
mac_partition_t mpart;
if (part_mac_read_ddb (dev_desc, &ddesc)) {
return (-1);
}
info->blksz = ddesc.blk_size;
if (part_mac_read_pdb (dev_desc, part, &mpart)) {
return (-1);
}
info->start = mpart.start_block;
info->size = mpart.block_count;
memcpy (info->type, mpart.type, sizeof(info->type));
memcpy (info->name, mpart.name, sizeof(info->name));
return (0);
}
四．常用 U-BOOT 命令介绍1.list 得到所有命令列表
2.help: help usb, 列出USB功能的使用说明
3.ping：注：只能开发板PING别的机器
4.setenv: 设置互环境变量:
5.setenv serverip 192.168.0.1
6.setenv ipaddr 192.168.0.56
7.setenv bootcmd ‘tftp 32000000 vmlinux; kgo 32000000 ’
8.saveenv: 保存环境变量
9.在设置好环境变量以后， 保存变量值
10.tftp: tftp 32000000 vmlinux, 把server（IP=环境变量中设置的serverip）中/tftpdroot/ 下的vmlinux通过TFTP读入到物理内存32000000处。
11.kgo: 起动没有压缩的linux内核，kgo 32000000
12.bootm:起动UBOOT TOOLS制作的压缩LINUX内核, bootm 3200000
13.protect: 对FLASH进行写保护或取消写保护， protect on 1:0-3(就是对第一块FLASH的0-3扇区进行保护)，protect off 1:0-3取消写保护
14.erase: 删除FLASH的扇区， erase 1:0-2(就是对每一块FLASH的0-2扇区进行删除)
15.cp: 在内存中复制内容， cp 32000000 0 40000(把内存中0x32000000开始的0x40000字节复制到0x0处)
16.mw: 对RAM中的内容写操作， mw 32000000 ff 10000(把内存0x32000000开始的0x10000字节设为0xFF)
17.md: 修改RAM中的内容, md 32000000（内存的起始地址）
18.usb:
lusb start: 起动usb 功能
lusb info: 列出设备
lusb scan: 扫描usb storage(u 盘)设备
19.fatls：列出DOS FAT文件系统， 如：fatls usb 0列出第一块U盘中的文件
20.fatload: 读入FAT中的一个文件，如：fatload usb 0:0 32000000 aa.txt
21.把USB中的aa.txt 读到物理内存0x32000000处！
22.flinfo: 列出flash的信息
23.loadb: 准备用KERMIT协议接收来自kermit或超级终端传送的文件。
24.nfs： nfs 32000000 192.168.0.2:aa.txt ， 把192.168.0.2(LINUX 的NFS文件系统)中的NFS文件系统中的aa.txt 读入内存0x32000000处。
![常见DOS命令1[图]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)