我正在尝试获得对我的中兴 F680 路由器的根访问权限。我已经有一个串行连接并且能够中断 U-Boot 自动启动。我遇到的问题是了解在以下环境中 U-Boot 是如何启动 Linux 的，而当我尝试在其 shell 中运行相同的命令时却失败了。环境：
CASset=max
EMAC=EMAC0
MACMODE=GMII
MALLOC_len=5
MPmode=SMP
amp_enable=no
autoload=no
baudrate=115200
boot_order=hd_scr hd_img pxe net_img net_scr
bootargs_dflt=$console $mtdparts $bootargs_root nfsroot=$serverip:$rootpath ip=$ipaddr:$serverip$bootargs_end $mvNetConfig video=dovefb:lcd0:$lcd0_params clcd.lcd0_enable=$lcd0_enable clcd.lcd_panel=$lcd_panel
bootargs_end=:10.4.50.254:255.255.255.0:AvantaLP:eth0:none
bootargs_root=root=/dev/nfs rw
bootcmd=setenv bootargs console=ttyS0,115200 root=/dev/ram0 rw load_ramdisk=1 rdinit=/sbin/init mv_switch_config=none memsize=$(memsize) mem=$(memsize); bootm 0x2000100;
bootdelay=3
bootfile=uboot.bin
bootsize=0x60000
cacheShare=no
console=console=ttyS0,115200
device_partition=0:1
disL2Cache=yes
disL2Prefetch=yes
disaMvPnp=no
eeeEnable=no
enaClockGating=no
enaCpuStream=no
enaDCPref=yes
enaFPU=yes
enaICPref=yes
enaMonExt=no
enaWrAllo=no
eth1addr=00:50:43:00:02:02
eth1mtu=1500
eth2addr=00:50:43:00:00:02
eth2mtu=1500
eth3addr=00:50:43:02:00:00
eth3mtu=1500
ethact=egiga0
ethaddr=00:50:43:00:02:02
ethmtu=1500
ethprime=egiga0
fdt_addr=2040000
flashsize=134217728
fullfile=upgrade.bin
ide_path=/
image_name=uImage
initrd_name=uInitrd
ipaddr=192.168.1.1
kernel_addr_r=2080000
kernelsize=0x16000000
lcd0_enable=0
lcd0_params=640x480-16@60
lcd_panel=0
linuzfile=vmlinuz.bin
loadaddr=0x02000000
loads_echo=0
memsize=253M
mtddevname=boot
mtddevnum=0
mtdids=nand0=mvebu-nand
mtdparts=mtdparts=mvebu-nand:1536k@0(boot),512k(env),20m(kernel0),20m(kernel1),6m(others),4m(parameter),8m(usercfg),4m(middleware),4m(wlan)
mvNetConfig=mv_switch_config=none
mv_pon_addr=00:50:43:02:00:00
nandEcc=1bit
nand_erasesize=20000
nand_oobsize=40
nand_writesize=800
netbsd_en=no
netdev=mii0
netmask=255.255.255.0
netretry=no
partition=nand0,0
pcieTune=no
pexMode=RC
pxe_files_load=:default.arm-armadaxp-db:default.arm-armadaxp:default.arm
pxefile_addr_r=3100000
ramdisk_addr_r=2880000
rcvr_image=rootfs.squashfs.rcvr.img
rootfile=rootfs.img
rootpath=/srv/nfs/
sata_delay_reset=0
sata_dma_mode=yes
script_addr_r=3000000
script_name=boot.scr
serverip=192.168.1.100
setL2CacheWT=no
silent=0
standalone=fsload 0x2000000 $image_name;setenv bootargs $console $mtdparts root=/dev/mtdblock0 rw ip=$ipaddr:$serverip$bootargs_end; bootm 0x2000000;
stderr=serial
stdin=serial
stdout=serial
versioninfo=U-Boot V2.0.10T5 0x1600000 0x1 0x82 0x87
vxworks_en=no
yuk_ethaddr=00:00:00:EE:51:81
Environment size: 2586/131068 bytes
从我的选择来看，第2 阶段应该加载boot.scr脚本，然后执行bootcmd. 但是尝试在 shell 中执行此操作失败。尝试运行boot.scr声明此地址没有有效图像并加载它fsload失败：
### JFFS2 loading 'boot.scr' to 0x3000000
Scanning JFFS2 FS: done.
find_inode failed for name=boot.scr
load: Failed to find inode
分区表确实存在：
=> mtdparts
mtdparts
device nand0 <mvebu-nand>, # parts = 9
#: name size offset mask_flags
0: boot 0x000000180000 0x000000000000 0
1: env 0x000000080000 0x000000180000 0
2: kernel0 0x000001400000 0x000000200000 0
3: kernel1 0x000001400000 0x000001600000 0
4: others 0x000000600000 0x000002a00000 0
5: parameter 0x000000400000 0x000003000000 0
6: usercfg 0x000000800000 0x000003400000 0
7: middleware 0x000000400000 0x000003c00000 0
8: wlan 0x000000400000 0x000004000000 0
但是列出其中任何一个都ls没有结果：
=> ls
Scanning JFFS2 FS: done.
我想知道 U-Boot 是否是在没有某些命令（即fdt缺少命令）或某些硬编码启动序列的情况下编译的？如果我不中断自动启动，它看起来像这样：
Hit any key to stop autoboot: 0
flash block_size is 0x20000
flash size(search addredd) is 0x8000000
search.c,372,do_search: search->result[index].entry = 0x200100
search.c,372,do_search: search->result[index].entry = 0x1600100
do_search ending
do_startup() start
select=0x1
search->result[select].entry=1600100
search->result[1].entry = 0x1600100
do_startup() ending
do_settings() start
do_setting versioninfo
btNumbers is V2.0.10T5
## Booting kernel from Legacy Image at 02000100 ...
Image Name: Linux Kernel Image
Created: 2017-10-25 9:10:20 UTC
Image Type: ARM Linux Kernel Image (gzip compressed)
Data Size: 15128571 Bytes = 14.4 MiB
Load Address: 00008000
Entry Point: 00008000
Verifying Checksum ... OK
Uncompressing Kernel Image ... OK
|-->setup versioninfo tag...versioninfo is U-Boot V2.0.10T5 0x1600000 0x1 0x82 0x87
Starting kernel ...