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Can I connect a CCI-400 ACE-Lite master interface to an AXI3 slave interface on a NIC-301?

Applies to: CCI-400 Cache Coherent Interconnect

Answer

Yes. You can connect devices with an AXI3 slave interface to the CCI-400, provided all of the following conditions are met:

  1. AMBA4 deprecates the WID signal, so an ACE-Lite master interface does not provide WID. If the NIC-301 slave interface, or a destination slave, requires the WID signal, then you must add some logic function to generate WID.

    Note: The NIC-301 uses WID if the path to a destination slave passes through a switch slave interface and the switch uses either the Single slave per ID or Single active slave cyclic dependency avoidance scheme. However, if the switch uses the default cyclic dependency avoidance scheme, that is Single slave, then WID is only a payload signal that passes through the NIC-301.

  2. The ACE-Lite master interface must not generate any transactions of greater than 16 beats in length. This only occurs if a master connected to CCI-400 generates non-shareable transactions of >16 beats.

  3. An AXI3 slave must not set BVALID HIGH before it completes the write address channel handshaking, that is AWVALID and AWREADY both HIGH, for the corresponding address. This behavior is permissible in AXI3, but not in AMBA 4.

    Note: If the AXI3 slave routes back to a NIC-301 ASIB slave interface that has a register slice on the AW channel then the BVALID signaling is AMBA 4 compliant.

  4. The ACE-Lite master must not generate barrier or cache maintenance transactions. You can configure each CCI-400 master interface to not issue these transactions. See the CCI-400 Integration Manual for more information.

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