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Hello,

I'm trying to get my xHCI driver (which works fine in QEMU aside from a single errata) to work on real hardware but I'm stuck configuring a USB2 storage device.

The first request (GET_DESCRIPTOR with DEVICE, STRING ...) always succeeds, but the second request (also GET_DESCRIPTOR) gets stuck at the setup TRB. When I pull out the device the controller sends a USB Transaction Error event, which points to the SETUP TRB of the second request.

The other built-in devices do seem to work properly, though one gives a Stall error when trying to read the device string (although reading the manufacturer string works, oddly). I have a hunch it is related but I can't figure out where to look.

My code is here.

I figured out the first issue: For some reason I was setting the chain bit in the data stage TRB. I removed that and now I can send more than one request.

The stall error persists though. I wasn't sure what was up with that (manufacturer string also returns a single non-ascii byte) until I noticed the indices are all zeroes. I've reread the wiki and apparently that means the device doesn't support it, whoops.

EDIT: the stall issue appears with a device that does have non-zero indices. The other ones just returns garbage. Manufacturer index works (it's some Hewlett Packard device, apparently).