LS1021A MII pin muxing

[fdm]

Hi,

There is a note for the Table 31 of the AN4878 "QorIQ LS1021A Design Checklist" that says:

1. When eTSEC 1 or eTSEC 2 are configured as MII mode some of the MII 1 and MII 2 signals are muxed with eTSEC 3 signals. In the RCW configuration eTSEC 3 must be selected as MII.

These muxed signals are TX_ER, CRS and COL.

Does eTSEC 3 have to be selected as MII when there's no need to use these muxed signals?

Can I simultaneusly use eTSEC 1 as RGMII 1, eTSEC 2 as MII 2 and eTSEC 3 as RMII EC3 in this case (when e.g. the MII2 is used for MAC-to-MAC full-duplex communication and TX_ER, CRS and COL are not needed)?

BR,

   Denis

[r8070z]

Have a great day,

The EC3 must be 011 due to the MII2 interface needs pins for signals TX_ER, CRS and COL. However it is not specified what signals applied to the MII2 interface TX_ER, CRS and COL internal inputs when EC3 is not set to 011. The MII2 operation in this case was not tested. It is better to create technical case with special request to the design group for clarification. See How I could create a Service Request? 

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