Devices with integrated PHY require 4 termination resistors. This are indexed as R37, R40, R41, and R42 in the reference schematic. They are required in order to pull up the receive and transmit differential pair. For most cases, 50 Ohm resistors with 1% are good enough. A separate resistor, RBIAS is also required to be connected to the RBIAS pin of the Ethernet Controller to set the bias voltage for the Ethernet Controller. It must be 4.87k ohm with 1% tolerance. Rbias resistor should be placed as close the RBIAS pin as possible with a short trace to the ground which is not shared with other MCU pins.