Dear Lyn.Tran@L-3com.com,

In message 615935CE76907149AFEC6599C969D4D5356B31@XCGTXH01.corp.eos.l-3com.com you wrote:

U-Boot is a Boot Loader, its primary purpose is to load some operating system. Can we use the U-Boot to load our small application before loading the operating system (Linux)? Our small application will read a FPGA bit file from the NAND flash and configure the FPGA.

You could do that - but it raises the question why you would need a separate application to do that - U-Boot itself contains code to boot FPGAs. Why are you not using U-Boots capabilities?

U-Boot includes a basic interactive command interpreter, support for download over Ethernet and the capability to program the flash. Can we update the FPGA bit file (by programming NAND flash using U-boot command)? If yes, then which flash file system that U-boot uses to program the flash? and does that flasf file system take care of wear leveling in the NAND flash?

You can use U-Boot to write JFFS2 and UBIFS images, but both of these are read-only, i. e. you cannot write a single file into an existing file system. Normally you would create a separate partition for such data if you need to update it in U-Boot context. UBI provides some flexible options for such tasks.

Best regards,

Wolfgang Denk