imx6 kernel

Hi

I use openjtag to debug kernel.

I key in "file vmlinux

target remote:3333

mon reset".

Then I got Invalid ACK 0 in JTAG-DP transaction

Tuntime Error:imx6.cfg:50

Invalid ACK 0 in JTAG-DP transaction…

How to step by step boot kernel in ddd with openjtag??

I key in halt in gdb and I got

"

accepting ‘gdb’ connection from 3333

number of cache level 1

imx6.cpu.0 cluster 0 core 0 multi core

target state: halted

target halted in ARM state due to debug-request, current mode: Supervisor

cpsr: 0x800f0193 pc: 0x8004d4bc

MMU: enabled, D-Cache: enabled, I-Cache: enabled

"

It seems I can step by step exec kernel.

How to step by step exec kernel??

I telnet openocd and I use “bp 0x10008000 4 hardware”.

When the Mars board reset.

The target didn’t stop at 0x10008000.

Is the address error??