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//
// Copyright 2016 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: LGPL-3.0-or-later
//

module axi_clip
  #(parameter WIDTH_IN=24,
    parameter WIDTH_OUT=16,
    parameter FIFOSIZE=0)  // leave at 0 for a normal single flop
   (input clk, input reset,
    input [WIDTH_IN-1:0] i_tdata, input i_tlast, input i_tvalid, output i_tready,
    output [WIDTH_OUT-1:0] o_tdata, output o_tlast, output o_tvalid, input o_tready);

   generate
     if (WIDTH_IN == WIDTH_OUT) begin
      assign o_tdata  = i_tdata;
      assign o_tlast  = i_tlast;
      assign o_tvalid = i_tvalid;
      assign i_tready = o_tready;
     end else begin
       wire overflow = |i_tdata[WIDTH_IN-1:WIDTH_OUT-1] & ~(&i_tdata[WIDTH_IN-1:WIDTH_OUT-1]);
       wire [WIDTH_OUT-1:0] out = overflow ?
         (i_tdata[WIDTH_IN-1] ? {1'b1,{(WIDTH_OUT-1){1'b0}}} : {1'b0,{(WIDTH_OUT-1){1'b1}}}) :
          i_tdata[WIDTH_OUT-1:0];

       axi_fifo #(.WIDTH(WIDTH_OUT+1), .SIZE(FIFOSIZE)) flop
         (.clk(clk), .reset(reset), .clear(1'b0),
          .i_tdata({i_tlast, out}), .i_tvalid(i_tvalid), .i_tready(i_tready),
          .o_tdata({o_tlast, o_tdata}), .o_tvalid(o_tvalid), .o_tready(o_tready),
          .occupied(), .space());
     end
   endgenerate

endmodule // axi_clip