Visible to Intel only — GUID: uat1488565668428
Ixiasoft
Visible to Intel only — GUID: uat1488565668428
Ixiasoft
51.3.1. Data Path
For transmit path, the GMII/MII data from the HPS goes through the transmit elastic buffer before going into the PCS GMII and MII port. The transmit elastic buffer is responsible for handling slight frequency differences between the transmit clock from HPS and the transmit clock generated from the PCS’s block.
The PCS block has separate GMII and MII ports while the HPS has only single GMII and MII ports. Therefore a mux is needed in the receive data path. During MII mode, the 4 bits MII receive data bus is duplicated in order to feed 8 bits to the GMII/MII receive data bus of HPS. The mac_speed information from the HPS or from the CSR in Intel FPGA HPS EMAC Interface Splitter core is used as mux select.