ss928 nand flash 加载kernel失败

1.成功下载了了uboot及kernel（.fip格式） 镜像
2.启动uboot加载失败，log如下：

nand read 0x42000000 0x100000 0x400000;bootm 0x42000000

NAND read: device 0 offset 0x100000, size 0x400000
4194304 bytes read: OK
Load fip from 0x0000000042000000 …

Firmware Image Package ToC:

• EL3 Runtime Firmware BL3-1: offset=0x88, size=0x60C8
• Non-Trusted Firmware BL3-3: offset=0x6150, size=0xA3DA90

Create Entry Point info …
Get - EL3 Runtime Firmware BL3-1
Get - Non-Trusted Firmware BL3-3
kernel_size[0xa3da90] fdt_size[0x5a50] fdt_addr[0x0000000050ab8000]
Invalid FDT at 0x0000000052f80000, hdr at 0x000000005007ffc0
exit not allowed from main input shell.