DP83867 PHY (and other TI industrial and automotive PHYs) have the capability to :
1. Generate the packetized data
2. Capture the number of frames received
3. Capture the number of frames received with errors.
These parameters can be used to check the throughput of the PHY without depending upon MAC or external data generator/checker.
Also the internal signal quality register can be used to check the health of the link. Have a look at attached document for further details :