secure OMAP-L138 boot from NOR flash

HI:

 we have some problems with secure omap-l138 device boot from nor flash.

We convert a dsp_ubl.out to ais format dsp_ubl_ais.bin with SecureHexAIS_OMAP-L138.exe tool and a ini file.

in the ini file, when we set the secure kernel exit type "bootExitType = NONSECURE" ,We boot  from nor flash succeed, however, we only change the secure kernel exit type to "bootExitType = SECUREWITHSK" in the ini file, and it can't boot. 

And for UART boot mode, we test above two, both work succeed.

How to deal with this prolem ?

Thanks!