Hi Yuri,
Thank you for your reply!
I followed the document IMX6HABUG , signed the u-boot.imx and got the u-boot-sigend-pad.imx, then burn it into the board. Then, I followed the document AN4581, programmed the fuses (use hexdump to display my fuse value and use fuse -prog to program it) . Before I programmed "fuse prog 0 6 0x2", which wrote in chapter 3.9 in AN4581, the board can be boot normally.
BTW:I haven't see anything before closing the device.
Best wishes,
Chang Tan