[U-Boot] Boot from USB support for Kirkwood SOC

[Prafulla Wadaskar]

Dear Remy Bohmer

I am going to start "boot from USB Support" development for kirkwood.
To sync with current USB framework in U-boot, and to reduce some rework at my side (since I am new to this driver).
May you please provide some guidelines/howto this regard?

FYI below is details about Kirkwood USB controller:  

Kirkwood contains a Universal Serial Bus (USB 2.0) port that includes an embedded USB 2.0 PHY.
The USB 2.0 interface contains a single dual-role controller that can act as a host or a peripheral
controller (USB controller). A bridge connects the controller to the internal Mbus interface (USB
bridge).
Embedded USB 2.0 PHY features include:
?? 480 Mbps High Speed (HS)/ 12 Mbps Full Speed (FS) and 1.5 Mbps Low Speed (LS) serial data
transmission rates
?? Synchronization/End-of-Packet (SYNC/EOP) generation and checking
?? Data and clock recovery from serial stream on the USB
?? Non Return to Zero Invert (NRZI) encoding/decoding with bit stuffing/unstuffing
?? Bit stuff error detections
?? Bit stuffing/unstuffing; bit stuff error detection
?? Holding registers to stage transmit and receive data
?? Supports USB 2.0 Test Modes
?? Ability to switch between FS and HS terminations/signaling
?? For more details, refer to the controller specification document USB-HS High-Speed
Controller Core Reference.

Regards..
Prafulla . .