usb: add xhci support

$subject says all.  Support for usb3 streams is not implemented yet,
otherwise it is fully functional.  Tested all usb devices supported
by qemu (keyboard, storage, usb hubs), except for usb attached scsi
in usb3 mode (which needs streams).

Tested on qemu only, tagged with QEMU_HARDWARE because of that.
Testing with physical hardware to be done.

Signed-off-by: Gerd Hoffmann <>
7 files changed