// ***************************************************************************
// ***************************************************************************
// Copyright 2014(c) Analog Devices, Inc.
//
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// ***************************************************************************
// ***************************************************************************
// Divides the input clock to SEL_0_DIV if clk_sel is 0 or SEL_1_DIV if
// clk_sel is 1. Provides a glitch free output clock
// IP uses BUFR/BUFGCE_DIV and BUFGMUX_CTRL primitives
// ***************************************************************************
// ***************************************************************************

`timescale 1ns/100ps

module util_clkdiv (
  input   clk,
  input   clk_sel,
  output  clk_out
 );

parameter SIM_DEVICE = "7SERIES";
parameter SEL_0_DIV = "4";
parameter SEL_1_DIV = "2";

  wire clk_div_sel_0_s;
  wire clk_div_sel_1_s;

generate if (SIM_DEVICE == "7SERIES") begin

  BUFR #(
    .BUFR_DIVIDE(SEL_0_DIV),
    .SIM_DEVICE("7SERIES")
  ) clk_divide_sel_0 (
    .I(clk),
    .CE(1),
    .CLR(0),
    .O(clk_div_sel_0_s));

  BUFR #(
    .BUFR_DIVIDE(SEL_1_DIV),
    .SIM_DEVICE("7SERIES")
  ) clk_divide_sel_1 (
    .I(clk),
    .CE(1),
    .CLR(0),
    .O(clk_div_sel_1_s));

end else if (SIM_DEVICE == "ULTRASCALE") begin

  BUFGCE_DIV #(
    .BUFGCE_DIVIDE(SEL_0_DIV)
  ) clk_divide_sel_0 (
    .I(clk),
    .CE(1),
    .CLR(0),
    .O(clk_div_sel_0_s));

  BUFGCE_DIV #(
    .BUFGCE_DIVIDE(SEL_1_DIV)
  ) clk_divide_sel_1 (
    .I(clk),
    .CE(1),
    .CLR(0),
    .O(clk_div_sel_1_s));

end endgenerate

  BUFGMUX_CTRL i_div_clk_gbuf (
    .I0(clk_div_sel_0_s), // 1-bit input: Clock input (S=0)
    .I1(clk_div_sel_1_s), // 1-bit input: Clock input (S=1)
    .S(clk_sel),
    .O (clk_out));

endmodule  // util_clkdiv