LFPS RESET packet on USB 3.0 bus

[Dinesh]

Hi,
I am using a USB 3.0 device with a Windows 8 laptop that has Intel(R) USB 3.0 eXtensible Host controller. When the device is streaming data continuously from device to host the device gets an LFPS RESET packet from the host. In addition I could also observe that USB protocol analyzer has logged many power management related packets. It would be great if someone can give some input on how to overcome or handle is this issue ?

regards,
Dinesh.

[Barry Twycross]

I'd only expect to get an LFPS reset if things have gone really badly. Do you get any hot resets before that happens? They show up as bursts if TS packets. The links try to keep things running independently and will try to retrain when they encounter a link error (hence the hot resets). It should only be when an error gets to the application layer that it might try a warm reset (with the LFPS).

If you're getting lots of retraining (hot resets), you may just have a bad bus. You might want to try different cabling. There are a lot of totally shitty cables out there, our signal integrity people could not find a good one on sale anywhere.