内核启动

最近仿照手册例程写了一个qt应用程序，编译通过以后分别把应用程序，桌面启动器，图标拷贝到文件系统的对应目录下，重新制作文件系统镜像，烧写到开发板中，启动开发板，内核不能进入控制台，打印信息如下：
##### EmbedSky BIOS for SKY2440/TQ2440 #####
Press Space key to Download Mode !
Booting Linux ...
Copy linux kernel from 0x00200000 to 0x30008000, size = 0x00200000 ... Copy Kern
el to SDRAM done,NOW, Booting Linux......
Uncompressing Linux.............................................................
......................................................... done, booting the kern
el.
Linux version 2.6.25.8-EmbedSky (root@localhost.localdomain) (gcc version 4.3.3
(Sourcery G++ Lite 2009q1-203) ) #8 Thu Mar 25 15:30:26 CST 2010
CPU: ARM920T [41129200] revision 0 (ARMv4T), cr=c0007177
Machine: SMDK2440
ATAG_INITRD is deprecated; please update your bootloader.
Memory policy: ECC disabled, Data cache writeback
CPU S3C2440A (id 0x32440001)
S3C244X: core 400.000 MHz, memory 100.000 MHz, peripheral 50.000 MHz
S3C24XX Clocks, (c) 2004 Simtec Electronics
CLOCK: Slow mode (1.500 MHz), fast, MPLL on, UPLL on
CPU0: D VIVT write-back cache
CPU0: I cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
CPU0: D cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 16256
Kernel command line: noinitrd root=/dev/mtdblock2 init=/linuxrc console=ttySAC0
irq: clearing pending ext status 00000400
irq: clearing pending status 02000000
irq: clearing subpending status 00000002
PID hash table entries: 256 (order: 8, 1024 bytes)
timer tcon=00500000, tcnt a2c1, tcfg 00000200,00000000, usec 00001eb8
Console: colour dummy device 80x30
console [ttySAC0] enabled
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 64MB = 64MB total
Memory: 60928KB available (3380K code, 368K data, 176K init)
SLUB: Genslabs=12, HWalign=32, Order=0-1, MinObjects=4, CPUs=1, Nodes=1
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
net_namespace: 152 bytes
NET: Registered protocol family 16
S3C2440: Initialising architecture
S3C2440: IRQ Support
S3C24XX DMA Driver, (c) 2003-2004,2006 Simtec Electronics
DMA channel 0 at c4800000, irq 33
DMA channel 1 at c4800040, irq 34
DMA channel 2 at c4800080, irq 35
DMA channel 3 at c48000c0, irq 36
S3C244X: Clock Support, DVS off
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
NET: Registered protocol family 2
IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
TCP established hash table entries: 2048 (order: 2, 16384 bytes)
TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
TCP: Hash tables configured (established 2048 bind 2048)
TCP reno registered
NetWinder Floating Point Emulator V0.97 (double precision)
yaffs Mar 19 2010 11:22:27 Installing.
io scheduler noop registered (default)
Console: switching to colour frame buffer device 40x15
fb0: s3c2410fb frame buffer device
TQ2440/SKY2440 LEDS, (c) 2008,2009 www.embedsky.net
EmbedSky-leds initialized
TQ2440/SKY2440 Beep, (c) 2008,2009 www.embedsky.net
EmbedSky-Beep initialized
s3c2440-uart.0: tq2440_serial0 at MMIO 0x50000000 (irq = 70) is a S3C2440
s3c2440-uart.1: tq2440_serial1 at MMIO 0x50004000 (irq = 73) is a S3C2440
s3c2440-uart.2: tq2440_serial2 at MMIO 0x50008000 (irq = 76) is a S3C2440
loop: module loaded
PPP generic driver version 2.4.2
PPP Deflate Compression module registered
PPP BSD Compression module registered
PPP MPPE Compression module registered
NET: Registered protocol family 24
PPPoL2TP kernel driver, V1.0
SLIP: version 0.8.4-NET3.019-NEWTTY (dynamic channels, max=256) (6 bit encapsula
tion enabled).
CSLIP: code copyright 1989 Regents of the University of California.
SLIP linefill/keepalive option.
dm9000 Ethernet Driver
eth%d: Invalid ethernet MAC address.  Please set using ifconfig
Now use the default MAC address: 10:32:54:76:98:ba
eth0: dm9000 at c480e000,c4810004 IRQ 51 MAC: 10:32:54:76:98:ba
Linux video capture interface: v2.00
Driver 'sd' needs updating - please use bus_type methods
S3C24XX NAND Driver, (c) 2004 Simtec Electronics
s3c2440-nand s3c2440-nand: Tacls=2, 20ns Twrph0=3 30ns, Twrph1=2 20ns
NAND device: Manufacturer ID: 0xec, Chip ID: 0x76 (Samsung NAND 64MiB 3,3V 8-bit
)
Scanning device for bad blocks
Creating 3 MTD partitions on "NAND 64MiB 3,3V 8-bit":
0x00000000-0x00040000 : "EmbedSky_Board_uboot"
0x00200000-0x00400000 : "EmbedSky_Board_kernel"
0x00200000-0x03df8000 : "EmbedSky_Board_yaffs2"
usbmon: debugfs is not available
Initial EmbedSky TWO USB HOST Driver!
s3c2410-ohci s3c2410-ohci: S3C24XX OHCI
s3c2410-ohci s3c2410-ohci: new USB bus registered, assigned bus number 1
s3c2410-ohci s3c2410-ohci: irq 42, io mem 0x49000000
usb usb1: configuration #1 chosen from 1 choice
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 2 ports detected
Initializing USB Mass Storage driver...
usbcore: registered new interface driver usb-storage
USB Mass Storage support registered.
mice: PS/2 mouse device common for all mice
EmbedSky TouchScreen successfully loaded
input: EmbedSky TouchScreen as /class/input/input0
S3C24XX RTC, (c) 2004,2006 Simtec Electronics
s3c2410-rtc s3c2410-rtc: rtc disabled, re-enabling
s3c2410-rtc s3c2410-rtc: rtc core: registered s3c as rtc0
i2c /dev entries driver
s3c2440-i2c s3c2440-i2c: slave address 0x10
s3c2440-i2c s3c2440-i2c: bus frequency set to 390 KHz
s3c2440-i2c s3c2440-i2c: i2c-0: S3C I2C adapter
s3c2440-sdi s3c2410-sdi: unable to get DMA channel.
s3c2440-sdi s3c2410-sdi: powered down.
s3c2440-sdi s3c2410-sdi: initialisation done.
s3c2440-sdi s3c2410-sdi: powered down.
hub 1-0:1.0: connect-debounce failed, port 2 disabled
hub 1-0:1.0: connect-debounce failed, port 2 disabled
hub 1-0:1.0: connect-debounce failed, port 2 disabled
hub 1-0:1.0: connect-debounce failed, port 2 disabled
hub 1-0:1.0: connect-debounce failed, port 2 disabled
hub 1-0:1.0: connect-debounce failed, port 2 disabled
hub 1-0:1.0: connect-debounce failed, port 2 disabled

内核打印到这里就一直重复上面这句话，在网上搜了一下也没有好的解答
不知道问题出在哪，希望版主和会员给予解答，万分感谢！

你把USB下载线拔掉试试。