[U-Boot] uboot_porting_guide

[Carmine Garripoli]

Hi everybody,
I'm an electronics engineering student and i'm very passionated about 
embedded systems. I would like to design my own totally custom board. 
Supposing that i've already choosen an ARM microprocessor supported by 
linux kernel, ram and nand flash and i've designed my board, i would 
like to know if there is a generic guide for "u-boot porting". I've 
already done a search on the net for "uboot porting guide" but 99,9% of 
material i found sounds like "...if your board is similar to another 
already existing", "....use command  make <boardname>_config with 
similar board" etc. etc.
Now does a general porting guide for uboot exist somewhere?

I really thank you for your answer
Metalgarri