Please follow the below steps to boot from SDRAM:
1. Create loader file for simple led dual core application with below options:
Boot mode : Memory
boot format : Include
width : 8 bit
Boot code : 0x1
2. In ROM application, Store the loader file at SDRAM and call ROM api as below.
0x02000000 - address of DDR2
ENUM_ROM_BCMD_DEVICE_MEMORY - Memory booting
3. Debug the ROM application, it runs the led application from SDRAM. Please refer the attached example.