[U-Boot] U-Boot default parameters

Dear Developers,

I am very new on embedded world, so I face off many difficulties because of my lack of experince.Now my problem is that I want to change some default boot parametes on U-Boot , like bootdelay, bootargs, etc. How can I do that changes on UBoot, and How can I cross compile U-Boot . There is a TI's TMS320DM355 davinci processor on my Workstation, I want to build U-Boot according to this processor. Can you give some ideas?

Regards

Canibek Sagin