Chipsets that provides access to baseband bits
The purpose of chipsets is to interface user data into a channel. User data are encoded (8b/10b, 128b/132b, scrambled, wrapped with sync, PID, and EOP patterns, supplied with CRC), then transmitted into physical media, with various enhancing tricks. The purpose of chipsets is exactly to offload all this stuff from real user data, so no such thing exists as you are asking for. 

To get the "baseband data", there are fast oscilloscopes (for USB 3.0 you need a 8 - 12 GHz scope) that can capture the channel data, and then post-process them (linearly equalized, got frequency lock, then symbol lock), and can give you raw data. This process is limited by scope memory, so you can't capture much. 

To access longer data, a special class of instruments exists called "protocol analyzers", who take the raw data and pre-process them (actually using the same PHY that is used in real communication channel), and raw decoded bytes can be logged.