[U-Boot] Writing a SATA driver

[Chris Ziomkowski]

Please forgive my dreadful ignorance. I have no experience with uBoot. I 
just downloaded the source code today.

I need to write a driver for a custom SATA IP core for MicroBlaze on a 
Xilinx ML505. I have not been successful finding any documentation which 
explains how to do this with uBoot.

 From looking at the source code in the drivers directory and looking 
for common functions (lucky there were 2 examples or I wouldn't have 
even got this far), it appears I need to write at least 4 functions:

init_sata()
scan_sata()
sata_read()
sata_write()

Is there some real documentation somewhere which explains exactly what 
these functions are supposed to do? Are there more that I have missed? I 
apologize if I am supposed to know these answers already, but after a 
few hours of investigation I have not been able to come up with anything 
useful.

Can someone recommend a course of action that will help me understand 
what I need to do?

Thank you for any assistance.

Chris