TMS320C6748: Secure boot exit with SECUREWITHSK jump to 0x01 address after about 30s.

Part Number:TMS320C6748

#1. Tested with a dead while(1) loop, when exit NONSECURE, it execute forever. when exit SECUREWITHSK, it execute about 30s, then jump to address 0x00000001. Why?

#2. Customer want to implement 2nd bootloader +3rd bootloader + application, so it need SECUREWITHSK in 2nd bootloader and 3rd bootloader, how to avoid #1 issue, and is there a demo to implement this?

#3. Is there benchmark on secure boot decryption?

#4. We found it can't access peripheral and configure register in SECUREWITHSK exit type, is it related to IOPU configuration? Please share me the documents: Memory_Protection_03_2012_v01.pdf and IOPU_Users_Guide.pdf