thanks for your answer. Let me update my situation a little bit. After some configuration, I have been able to load my preloader, so now I have 2 choices:
- Use only preloader and baremetal application
- Use uboot to first load .rbf file then jump to application ( and of course with uboot script)
With the first one, when making the preloader, I modify the field FAT_LOAD_PAYLOAD_NAME to "hello_world.img". Then compiling and load it to my SD without problem. I found in uboot-socfpga folder having examples sub-folder with hello_world.bin inside, then I converted it to .img file and drag it to my SD card. However, when plugged it into the board, on Putty terminal I had my u-boot SPL configuration and went to reading hello_world.img but it stucked over there and went nowhere.
With the second one, I make a uboot by make command and create my uboot script that first load .rbf file, then jump to my bare metal application. Since my EDS does not license so I used the same hello_world example. Everything was going well until I got this error:
MAYBE you should read doc/README.arm-unaligned-accesses
This happened when it tried to run the application.
Once again, I appreciate your help and I hope you can give me a clue for this problem.
Cheers.