//======================================================================
//
// clkmgr_dcm_new.v
// ---------------
// Xilinx DCM_SP primitive wrapper to avoid using Clocking Wizard IP core.
// FPGA framework.
//
//
// Author: Pavel Shatov
// Copyright (c) 2015, NORDUnet A/S All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// - Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.
//
// - Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the distribution.
//
// - Neither the name of the NORDUnet nor the names of its contributors may
//   be used to endorse or promote products derived from this software
//   without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
//======================================================================

module clkmgr_dcm_new
	(
		input		wire	clk_in,
      input		wire	reset_in,
		
      output	wire	gclk_missing_out,

      output	wire	clk_out,
      output	wire	clk_valid_out
	);
	
		
		//
		// Parameters
		//
	parameter	CLK_OUT_MUL		= 2;
	parameter	CLK_OUT_DIV		= 2;
	
	
		//
		// DCM_SP
		//
	wire				dcm_clk_0;
	wire				dcm_clk_feedback;
	wire 				dcm_clk_fx;
	wire				dcm_locked_int;
	wire	[ 7: 0]	dcm_status_int;
	
	DCM_SP #
	(
		.STARTUP_WAIT			("FALSE"),
		.DESKEW_ADJUST			("SYSTEM_SYNCHRONOUS"),
		.CLK_FEEDBACK			("1X"),
		
		.PHASE_SHIFT			(0),
		.CLKOUT_PHASE_SHIFT	("NONE"),
		
		.CLKIN_PERIOD			(20.0),	// 50 MHz => 20 ns
		.CLKIN_DIVIDE_BY_2	("FALSE"),
		
		.CLKDV_DIVIDE			(5.000),
		.CLKFX_MULTIPLY		(CLK_OUT_MUL),
		.CLKFX_DIVIDE			(CLK_OUT_DIV)
	)
	DCM_SP_inst
	(
		.RST			(reset_in),
		
		.CLKIN		(clk_in),
		.CLKFB		(dcm_clk_feedback),
		.CLKDV		(),
		
		.CLK0			(dcm_clk_0),
		.CLK90		(),
		.CLK180		(),
		.CLK270		(),
		
		.CLK2X      (),
		.CLK2X180	(),
		
		.CLKFX		(dcm_clk_fx),
		.CLKFX180   (),
		
		.PSCLK		(1'b0),
		.PSEN			(1'b0),
		.PSINCDEC	(1'b0),
		.PSDONE		(),

		.LOCKED		(dcm_locked_int),
		.STATUS		(dcm_status_int),

		.DSSEN		(1'b0)
	);


		//
		// Mapping
		//
	assign	gclk_missing_out	= dcm_status_int[1];
	assign	clk_valid_out		= dcm_locked_int & ((dcm_status_int[2:1] == 2'b00) ? 1'b1 : 1'b0);


		//
		// Feedback
		//
	BUFG BUFG_feedback
	(
		.I		(dcm_clk_0),
		.O		(dcm_clk_feedback)
	);

		//
		// Output Buffer
		//
	BUFG BUFG_output
	(
		.I		(dcm_clk_fx),
		.O		(clk_out)
	);


endmodule

//======================================================================
// EOF clkmgr_dcm_new.v
//======================================================================