pluto_hdl_adi/library/common/ad_csc_1_add.v

152 lines
5.6 KiB
Verilog

// ***************************************************************************
// ***************************************************************************
// Copyright 2011(c) Analog Devices, Inc.
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
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// from this software without specific prior written permission.
// - The use of this software may or may not infringe the patent rights
// of one or more patent holders. This license does not release you
// from the requirement that you obtain separate licenses from these
// patent holders to use this software.
// - Use of the software either in source or binary form, must be run
// on or directly connected to an Analog Devices Inc. component.
//
// THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
// INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A
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// RIGHTS, 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.
// ***************************************************************************
// ***************************************************************************
// ***************************************************************************
// ***************************************************************************
// Color Space Conversion, adder. This is a simple adder, but had to be
// pipe-lined for faster clock rates. The delay input is delay-matched to
// the sum pipe-line stages
`timescale 1ps/1ps
module ad_csc_1_add #(
parameter DELAY_DATA_WIDTH = 16) (
// all signed
input clk,
input [24:0] data_1,
input [24:0] data_2,
input [24:0] data_3,
input [24:0] data_4,
output reg [ 7:0] data_p,
// delay match
input [DW:0] ddata_in,
output reg [DW:0] ddata_out);
localparam DW = DELAY_DATA_WIDTH - 1;
// internal registers
reg [DW:0] p1_ddata = 'd0;
reg [24:0] p1_data_1 = 'd0;
reg [24:0] p1_data_2 = 'd0;
reg [24:0] p1_data_3 = 'd0;
reg [24:0] p1_data_4 = 'd0;
reg [DW:0] p2_ddata = 'd0;
reg [24:0] p2_data_0 = 'd0;
reg [24:0] p2_data_1 = 'd0;
reg [DW:0] p3_ddata = 'd0;
reg [24:0] p3_data = 'd0;
// internal signals
wire [24:0] p1_data_1_p_s;
wire [24:0] p1_data_1_n_s;
wire [24:0] p1_data_1_s;
wire [24:0] p1_data_2_p_s;
wire [24:0] p1_data_2_n_s;
wire [24:0] p1_data_2_s;
wire [24:0] p1_data_3_p_s;
wire [24:0] p1_data_3_n_s;
wire [24:0] p1_data_3_s;
wire [24:0] p1_data_4_p_s;
wire [24:0] p1_data_4_n_s;
wire [24:0] p1_data_4_s;
// pipe line stage 1, get the two's complement versions
assign p1_data_1_p_s = {1'b0, data_1[23:0]};
assign p1_data_1_n_s = ~p1_data_1_p_s + 1'b1;
assign p1_data_1_s = (data_1[24] == 1'b1) ? p1_data_1_n_s : p1_data_1_p_s;
assign p1_data_2_p_s = {1'b0, data_2[23:0]};
assign p1_data_2_n_s = ~p1_data_2_p_s + 1'b1;
assign p1_data_2_s = (data_2[24] == 1'b1) ? p1_data_2_n_s : p1_data_2_p_s;
assign p1_data_3_p_s = {1'b0, data_3[23:0]};
assign p1_data_3_n_s = ~p1_data_3_p_s + 1'b1;
assign p1_data_3_s = (data_3[24] == 1'b1) ? p1_data_3_n_s : p1_data_3_p_s;
assign p1_data_4_p_s = {1'b0, data_4[23:0]};
assign p1_data_4_n_s = ~p1_data_4_p_s + 1'b1;
assign p1_data_4_s = (data_4[24] == 1'b1) ? p1_data_4_n_s : p1_data_4_p_s;
always @(posedge clk) begin
p1_ddata <= ddata_in;
p1_data_1 <= p1_data_1_s;
p1_data_2 <= p1_data_2_s;
p1_data_3 <= p1_data_3_s;
p1_data_4 <= p1_data_4_s;
end
// pipe line stage 2, get the sum (intermediate, 4->2)
always @(posedge clk) begin
p2_ddata <= p1_ddata;
p2_data_0 <= p1_data_1 + p1_data_2;
p2_data_1 <= p1_data_3 + p1_data_4;
end
// pipe line stage 3, get the sum (final, 2->1)
always @(posedge clk) begin
p3_ddata <= p2_ddata;
p3_data <= p2_data_0 + p2_data_1;
end
// output registers, output is unsigned (0 if sum is < 0) and saturated.
// the inputs are expected to be 1.4.20 format (output is 8bits).
always @(posedge clk) begin
ddata_out <= p3_ddata;
if (p3_data[24] == 1'b1) begin
data_p <= 8'h00;
end else if (p3_data[23:20] == 'd0) begin
data_p <= p3_data[19:12];
end else begin
data_p <= 8'hff;
end
end
endmodule
// ***************************************************************************
// ***************************************************************************