OSDev.org

I'd like first to thank you all for this fantastic website.

I'm planning to implement an xHCI for my OS; but I don't want to implement previous OHCI, UHCI and EHCI specifications.

I'm currently reading the specs. If I understood the thing correctly, I can have an USBD with only an xHCI behind it. Am I correct?

I'd like to have support for USB3.0 only, but I read that implementing previous versions is necessary for full support of this specification...

Thanks for your advice

I haven't been took in-depth look of xhci.
but form what i know - yes, the xhci backward support is now in-chip (instead of companion chips)
i have no ideal what does it mean from implementation point of view.

I'm on the way to read the whole USB/xHCI specs, so I'll post what I find out later.

At http://prettyos.de we are just developing an xHCI driver. We are going to try to integrate it into the general usb interface already working with UHCI, OHCI, EHCI.

update xhci/usb3:
PrettyOS has now a testwise working xhci module. With vmware we observed correct usb enumeration (slot state: enabled (0) ==> addressed (0)). With real hardware there are still "parameter errors". Perhaps anybody could help to sort that out.

PS: For a working xhci we had to implement acpi, apic, msi (for interrupts).

http://prettyos.de