Neither of the the bridges on my laptop (NEC) or my desktop (VIA) show a debug implementation.
Please add PCI ids and chip names on http://wiki.linuxbios.org/index.php/EHCI_Debug_Port or send me a quick message so I can do it.
PCI: 1033:00e0 00:13.2 USB Controller: NEC Corporation USB 2.0 (rev 02) (prog-if 20 [EHCI]) Subsystem: Compaq Computer Corporation Unknown device 0056 Flags: bus master, medium devsel, latency 132, IRQ 11 Memory at f0018c00 (32-bit, non-prefetchable) [size=256] Capabilities: [40] Power Management version 2
PCI: 1106:3104 00:10.3 USB Controller: VIA Technologies, Inc. USB 2.0 (rev 82) (prog-if 20 [EHCI]) Subsystem: VIA Technologies, Inc. USB 2.0 Flags: bus master, medium devsel, latency 32, IRQ 17 Memory at dfffff00 (32-bit, non-prefetchable) [size=256] Capabilities: [80] Power Management version 2