The RX path performs the deserialization of single-bit data on the RX lane to
parallel application data of width 12, 14, or 16. Once deserialization is complete,
app_rx_valid is asserted high. After this, you can
sample the data. Deserialization is done in the following steps:
- Deserialization in PHY.
- Calibration and tracking of RX data.
- Gearbox logic.