Korona wrote:
I don't see where the spec states that capability 0x01 has to be the first capability.
Section 7.1.1 in version 1.1
"This register is an xHCI extended capability register. It includes a specific function section and a pointer
to the next xHCI Extended Capability. This register is used by pre-OS software (BIOS) and the operating
system to coordinate ownership of the xHC."
It is used as a start for the extended capabilities list and is at offset "xECP + 00h".
Therefore, it is pretty much required to be present. I don't know of any xHCI implementation that does not support Legacy Support, but it has been a few months since I have worked with USB.
Ben
http://www.fysnet.net/the_universal_serial_bus.htm