pluto_hdl_adi/library/axi_dmac/response_handler.v

// ***************************************************************************
// ***************************************************************************
// Copyright (C) 2014-2023 Analog Devices, Inc. All rights reserved.
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// of various HDL (Verilog or VHDL) components. The individual modules are
// developed independently, and may be accompanied by separate and unique license
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// The user should read each of these license terms, and understand the
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// ***************************************************************************
// ***************************************************************************

`timescale 1ns/100ps

module response_handler #(

  parameter ID_WIDTH = 3
) (
  input clk,
  input resetn,

  input bvalid,
  output bready,
  input [1:0] bresp,

  output reg [ID_WIDTH-1:0] id,
  input [ID_WIDTH-1:0] request_id,

  input enable,
  output reg enabled,

  input eot,

  output resp_valid,
  input resp_ready,
  output resp_eot,
  output [1:0] resp_resp
);

  `include "resp.vh"
  `include "inc_id.vh"

  assign resp_resp = bresp;
  assign resp_eot = eot;

  wire active = id != request_id;

  assign bready = active && resp_ready;
  assign resp_valid = active && bvalid;

  // We have to wait for all responses before we can disable the response handler
  always @(posedge clk) begin
    if (resetn == 1'b0) begin
      enabled <= 1'b0;
    end else if (enable == 1'b1) begin
        enabled <= 1'b1;
    end else if (request_id == id) begin
        enabled <= 1'b0;
    end
  end

  always @(posedge clk) begin
    if (resetn == 1'b0) begin
      id <= 'h0;
    end else if (bready == 1'b1 && bvalid == 1'b1) begin
      id <= inc_id(id);
    end
  end

endmodule