如何用openjtag调试linux内核？

我现在在OK6410的开发板上刚刚学linux，这两天我想用OPENJTAG将linux内核加载到SDRAM中运行，可以加载但是不运行，是什么原因呢？我试了linux 的zImage和Image两种映像，是编译映像文件的问题吗？（没将其设为SDRAM中运行）

在openocd中具体的命令如下：
[taikonaut@sky workspace]$ telnet localhost 4444
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Open On-Chip Debugger
> reset halt
JTAG tap: s3c6410.etb tap/device found: 0x2b900f0f (mfg: 0x787, part: 0xb900, ver: 0x2)
JTAG tap: s3c6410.cpu tap/device found: 0x07b76f0f (mfg: 0x787, part: 0x7b76, ver: 0x0)
found ARM1176
s3c6410.cpu: ran after reset and before halt ...
target state: halted
target halted in ARM state due to debug-request, current mode: Supervisor
cpsr: 0x20000113 pc: 0x000001a4
> arm mcr 15 0 1 0 0 0
> step
target state: halted
target halted in ARM state due to single-step, current mode: Supervisor
cpsr: 0x20000113 pc: 0x000001a8
> load_image init.bin 0x0c000000
776 bytes written at address 0x0c000000
downloaded 776 bytes in 0.043064s (17.597 KiB/s)
> resume 0x0c000000            
invalid mode value encountered 8
target state: halted
unrecognized psr mode: 0x8
target halted in ARM state due to breakpoint, current mode: UNRECOGNIZED
cpsr: 0x0c000308 pc: 0x0c000300
> halt                          
target state: halted
target halted in ARM state due to debug-request, current mode: Supervisor
cpsr: 0x200001d3 pc: 0x0c0000d8
> load_image zImage 0x50800000  
2142188 bytes written at address 0x50800000
downloaded 2142188 bytes in 66.627258s (31.398 KiB/s)
> bp 0x50800000 4 hw
breakpoint set at 0x50800000
> bp               
0x50800000, 0x4, 0
> resume
>

使用resume命令后内核也没有运行起来，我改变了内核的加载地址情况也一样，是不是地址还有问题？
谢谢！