Unfortunately, none of the current ones from Renesas, VIA Labs or Fresco Logic do, and neither of these manufacturers are planning to add the capability on their existing controllers, through a firmware update for instance... Instead, they only have plans to provide it on their next generation controllers, which won't be available for some time (yes, I am aware that the new Renesas chips have been announced since 2011.03, but I have yet to see a PCI-E expansion card with one of those -- If you actually managed to get your hands on one, I'd like to hear from you!
UPDATE 2011.08.29: Apparently those guys did... but as a world exclusive, since these cards won't be available till later on this year. Darn!).
UPDATE 2012.01.10: At long friggin' last, uPD720201 based PCIE cards, with debug support, are starting to become available, one such being the Buffalo IFC-PCIE4U3S. Only seems to be available in Asia and Australia at the moment however, but even then, orders may not be satisfied before February because of lack of availability...
So this means, if you have a NEC/Renesas uPD720200/uPD720200A, a VIA Labs VL800/801 or a Fresco Logic FL1000/FL1009 based USB 3.0 controller, you're out of luck with regards to USB 3.0 debug.
This doesn't bode too well for USB 3.0 as replacement for legacy RS232 ports...
Oh and the other disappointing part of the current crop of PCIE-USB3 controllers is they don't support USB-3.0 boot either. Quite the letdown...
Hint: If you want to display the Extended Capabilities of your controller, you can do so by modifying the
drivers/usb/host/xhci-mem.cin () on a recent Linux kernel, as it already has some code to scan the extended caps. Using this method, I was able to find that, as of firmware 4015, the only Extended Capabilities provided by an uPD720200 USB 3.0 controller was "USB Legacy Support" (xHCI specs chpater 7.1) and "xHCI Supported Protocol" (7.2). The same applies for a Fresco Logic FL1000 based controller that I just got my hands on, though this one also sports vendor specific Extended Capabilities, with IDs 192 and 193.
Below are the answers from various manufacturers regarding their planned support of USB 3.0 debug. Being mostly interested in addon cards for existing systems, I haven't asked Intel or AMD.
"The uPD720200 does not support the debug port capability, and there is no plan to add it. But we have already added debug port support to our newer USB3 host controllers, uPD720201 and uPD720202."VIA Labs:
"VL800/801 doesn't support debug port capability. As I know, the only one support is Renesas 3rd gen. host controller UPD720201_202, we plan to add this feature with VL805 that will MP next year."Fresco Logic:
"FL1000/FL1009 didn't support USB debug extended capability.
We are doing it (for the next generation of controllers) and the schedule will be 2012/Q1."