A11.2 Transfer size support

ACP supports the following read-request transfer size and length combinations:

  • 64 byte INCR request characterized by:

    • ARLEN is 0x03, 4 beats.

    • ARADDR aligned to 64 byte boundary, so ARADDR[5:0] is 0b00 0000.
    • ARSIZE and ARBURST assume values of 0b100 and INCR respectively.
  • 16 byte INCR request characterized by:

    • ARLEN is 0x00, 1 beat.

    • ARADDR aligned to 16 byte boundary, so ARADDR[3:0] is 0x0.

ACP supports the following write-request transfer size and length combinations:

  • 64 byte INCR request characterized by:

    • AWLEN is 0x03, 4 beats.

    • AWADDR aligned to 64 byte boundary, so AWADDR[5:0] is 0b00 0000.
    • AWSIZE and AWBURST assume values of 0b100 and INCR respectively.
    • WSTRB for all beats must be the same and either all asserted or all deasserted.
  • 16 byte INCR request characterized by:

    • AWLEN is 0x00, 1 beat.

    • AWADDR aligned to 16 byte boundary, so AWADDR[3:0] is 0x0.
    • AWSIZE and AWBURST assume values of 0b100 and INCR respectively.
    • WSTRB can take any value.

Requests not meeting these restrictions cause a SLVERR response on RRESP or BRESP.

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