/**************************************************************************
 *                                                                        *
 *               Copyright (C) 1994, Silicon Graphics, Inc.               *
 *                                                                        *
 *  These coded instructions, statements, and computer programs  contain  *
 *  unpublished  proprietary  information of Silicon Graphics, Inc., and  *
 *  are protected by Federal copyright  law.  They  may not be disclosed  *
 *  to  third  parties  or copied or duplicated in any form, in whole or  *
 *  in part, without the prior written consent of Silicon Graphics, Inc.  *
 *                                                                        *
 *************************************************************************/

// $Id: ep_cc.v,v 1.1 2002/03/28 00:26:13 berndt Exp $

////////////////////////////////////////////////////////////////////////
//
// Project Reality
//
// module:      ep_cc
// description: Top level for edge walker pipe.
//
// designer:    Phil Gossett
// date:        6/7/95
//
////////////////////////////////////////////////////////////////////////

module ep_cc (gclk, dither_type, cycle_type,
	st_span_10d, d_3d, cv_x_offset, cv_y_offset, cv_cvg, cv_mask,
	x_dither, y_dither,
	st_span_st_r, st_span_st_g, st_span_st_b, st_span_st_a,
	st_span_st_z, st_span_tf, st_span_cc, st_span_bl, st_span_ms,
	d_r, d_g, d_b, d_a, d_z,
	x_offset_r, x_offset_g, x_offset_b, x_offset_a, x_offset_z,
	y_offset_r, y_offset_g, y_offset_b, y_offset_a, y_offset_z,
	cvg_cc, mask_bl, rgb_dither, alpha_dither);

input gclk;
input dither_type;
input [1:0] cycle_type;
input st_span_10d;
input [21:0] d_3d;
input [1:0] cv_x_offset;
input [1:0] cv_y_offset;
input [3:0] cv_cvg;
input cv_mask;
input [1:0] x_dither;
input [1:0] y_dither;

output st_span_st_r;
output st_span_st_g;
output st_span_st_b;
output st_span_st_a;
output st_span_st_z;
output st_span_tf;
output st_span_cc;
output st_span_bl;
output st_span_ms;
output [21:0] d_r;
output [21:0] d_g;
output [21:0] d_b;
output [21:0] d_a;
output [21:0] d_z;
output [1:0] x_offset_r;
output [1:0] x_offset_g;
output [1:0] x_offset_b;
output [1:0] x_offset_a;
output [1:0] x_offset_z;
output [1:0] y_offset_r;
output [1:0] y_offset_g;
output [1:0] y_offset_b;
output [1:0] y_offset_a;
output [1:0] y_offset_z;
output [3:0] cvg_cc;
output mask_bl;
output [2:0] rgb_dither;
output [2:0] alpha_dither;

wire [2:0] pre_dither;

reg [2:0] dither_0d;
reg [2:0] dither_1d;
reg [2:0] dither_2d;
reg [2:0] dither_3d;
reg [2:0] dither_4d;
reg [2:0] dither_5d;
reg [2:0] dither_6d;
reg [2:0] dither_7d;
reg [2:0] dither_8d;
reg [2:0] dither_9d;
reg [2:0] dither_10d;
reg [2:0] dither_11d;
reg [2:0] dither_12d;
reg [2:0] dither_13d;
reg [2:0] dither_14d;
reg [2:0] dither_15d;
reg [2:0] dither_16d;
reg [2:0] dither_17d;
reg [2:0] dither_18d;
reg [2:0] dither_19d;
reg [2:0] dither_20d;
reg [2:0] dither_21d;
reg [2:0] dither_22d;
reg [2:0] dither_23d;
reg [2:0] dither_24d;
reg [2:0] dither_25d;
reg [2:0] dither_26d;
reg [2:0] dither_27d;
reg [2:0] dither_28d;
reg [2:0] dither_29d;
reg [2:0] dither_30d;
reg [2:0] dither_31d;
reg [2:0] dither_32d;
reg st_span_11d;
reg st_span_12d;
reg st_span_13d;
reg st_span_14d;
reg st_span_15d;
reg st_span_16d;
reg st_span_17d;
reg st_span_18d;
reg st_span_19d;
reg st_span_20d;
reg st_span_21d;
reg st_span_22d;
reg st_span_23d;
reg st_span_24d;
reg st_span_25d;
reg st_span_26d;
reg [21:0] d_4d;
reg [21:0] d_5d;
reg [21:0] d_6d;
reg [21:0] d_7d;
reg [21:0] d_8d;
reg [21:0] d_9d;
reg [21:0] d_10d;
reg [21:0] d_11d;
reg [21:0] d_12d;
reg [21:0] d_13d;
reg [21:0] d_14d;
reg [21:0] d_15d;
reg [1:0] x_offset_1d;
reg [1:0] x_offset_2d;
reg [1:0] x_offset_3d;
reg [1:0] x_offset_4d;
reg [1:0] x_offset_5d;
reg [1:0] x_offset_6d;
reg [1:0] x_offset_7d;
reg [1:0] x_offset_8d;
reg [1:0] x_offset_9d;
reg [1:0] x_offset_10d;
reg [1:0] x_offset_11d;
reg [1:0] x_offset_12d;
reg [1:0] x_offset_13d;
reg [1:0] x_offset_14d;
reg [1:0] x_offset_15d;
reg [1:0] x_offset_16d;
reg [1:0] x_offset_17d;
reg [1:0] x_offset_18d;
reg [1:0] x_offset_19d;
reg [1:0] x_offset_20d;
reg [1:0] x_offset_21d;
reg [1:0] x_offset_22d;
reg [1:0] x_offset_23d;
reg [1:0] x_offset_24d;
reg [1:0] x_offset_25d;
reg [1:0] x_offset_26d;
reg [1:0] x_offset_27d;
reg [1:0] y_offset_1d;
reg [1:0] y_offset_2d;
reg [1:0] y_offset_3d;
reg [1:0] y_offset_4d;
reg [1:0] y_offset_5d;
reg [1:0] y_offset_6d;
reg [1:0] y_offset_7d;
reg [1:0] y_offset_8d;
reg [1:0] y_offset_9d;
reg [1:0] y_offset_10d;
reg [1:0] y_offset_11d;
reg [1:0] y_offset_12d;
reg [1:0] y_offset_13d;
reg [1:0] y_offset_14d;
reg [1:0] y_offset_15d;
reg [1:0] y_offset_16d;
reg [1:0] y_offset_17d;
reg [1:0] y_offset_18d;
reg [1:0] y_offset_19d;
reg [1:0] y_offset_20d;
reg [1:0] y_offset_21d;
reg [1:0] y_offset_22d;
reg [1:0] y_offset_23d;
reg [1:0] y_offset_24d;
reg [1:0] y_offset_25d;
reg [1:0] y_offset_26d;
reg [1:0] y_offset_27d;
reg [3:0] cvg_1d;
reg [3:0] cvg_2d;
reg [3:0] cvg_3d;
reg [3:0] cvg_4d;
reg [3:0] cvg_5d;
reg [3:0] cvg_6d;
reg [3:0] cvg_7d;
reg [3:0] cvg_8d;
reg [3:0] cvg_9d;
reg [3:0] cvg_10d;
reg [3:0] cvg_11d;
reg [3:0] cvg_12d;
reg [3:0] cvg_13d;
reg [3:0] cvg_14d;
reg [3:0] cvg_15d;
reg [3:0] cvg_16d;
reg [3:0] cvg_17d;
reg [3:0] cvg_18d;
reg [3:0] cvg_19d;
reg [3:0] cvg_20d;
reg [3:0] cvg_21d;
reg [3:0] cvg_22d;
reg [3:0] cvg_23d;
reg [3:0] cvg_24d;
reg [3:0] cvg_25d;
reg [3:0] cvg_26d;
reg mask_1d;
reg mask_2d;
reg mask_3d;
reg mask_4d;
reg mask_5d;
reg mask_6d;
reg mask_7d;
reg mask_8d;
reg mask_9d;
reg mask_10d;
reg mask_11d;
reg mask_12d;
reg mask_13d;
reg mask_14d;
reg mask_15d;
reg mask_16d;
reg mask_17d;
reg mask_18d;
reg mask_19d;
reg mask_20d;
reg mask_21d;
reg mask_22d;
reg mask_23d;
reg mask_24d;
reg mask_25d;
reg mask_26d;
reg mask_27d;
reg mask_28d;
reg mask_29d;

wire two_cyc;
wire dither_mask;

xo02d1h dit0 (.a1(x_dither[1]), .a2(y_dither[1]), .z(pre_dither[0]));
fn05d2  msk1 (.a1(x_dither[0]), .b1(dither_type), .zn(dither_mask));
xo02d1h dit1 (.a1(dither_mask), .a2(y_dither[1]), .z(pre_dither[1]));
xo02d1h dit2 (.a1(x_dither[0]), .a2(y_dither[0]), .z(pre_dither[2]));

always @(posedge gclk)
begin
	dither_0d <= pre_dither;
	dither_1d <= dither_0d;
	dither_2d <= dither_1d;
	dither_3d <= dither_2d;
	dither_4d <= dither_3d;
	dither_5d <= dither_4d;
	dither_6d <= dither_5d;
	dither_7d <= dither_6d;
	dither_8d <= dither_7d;
	dither_9d <= dither_8d;
	dither_10d <= dither_9d;
	dither_11d <= dither_10d;
	dither_12d <= dither_11d;
	dither_13d <= dither_12d;
	dither_14d <= dither_13d;
	dither_15d <= dither_14d;
	dither_16d <= dither_15d;
	dither_17d <= dither_16d;
	dither_18d <= dither_17d;
	dither_19d <= dither_18d;
	dither_20d <= dither_19d;
	dither_21d <= dither_20d;
	dither_22d <= dither_21d;
	dither_23d <= dither_22d;
	dither_24d <= dither_23d;
	dither_25d <= dither_24d;
	dither_26d <= dither_25d;
	dither_27d <= dither_26d;
	dither_28d <= dither_27d;
	dither_29d <= dither_28d;
	dither_30d <= dither_29d;
	dither_31d <= dither_30d;
	dither_32d <= dither_31d;

	st_span_11d <= st_span_10d;
	st_span_12d <= st_span_11d;
	st_span_13d <= st_span_12d;
	st_span_14d <= st_span_13d;
	st_span_15d <= st_span_14d;
	st_span_16d <= st_span_15d;
	st_span_17d <= st_span_16d;
	st_span_18d <= st_span_17d;
	st_span_19d <= st_span_18d;
	st_span_20d <= st_span_19d;
	st_span_21d <= st_span_20d;
	st_span_22d <= st_span_21d;
	st_span_23d <= st_span_22d;
	st_span_24d <= st_span_23d;
	st_span_25d <= st_span_24d;
	st_span_26d <= st_span_25d;

	d_4d  <= d_3d;
	d_5d  <= d_4d;
	d_6d  <= d_5d;
	d_7d  <= d_6d;
	d_8d  <= d_7d;
	d_9d  <= d_8d;
	d_10d <= d_9d;
	d_11d <= d_10d;
	d_12d <= d_11d;
	d_13d <= d_12d;
	d_14d <= d_13d;
	d_15d <= d_14d;

	x_offset_1d  <= cv_x_offset;
	x_offset_2d  <= x_offset_1d;
	x_offset_3d  <= x_offset_2d;
	x_offset_4d  <= x_offset_3d;
	x_offset_5d  <= x_offset_4d;
	x_offset_6d  <= x_offset_5d;
	x_offset_7d  <= x_offset_6d;
	x_offset_8d  <= x_offset_7d;
	x_offset_9d  <= x_offset_8d;
	x_offset_10d <= x_offset_9d;
	x_offset_11d <= x_offset_10d;
	x_offset_12d <= x_offset_11d;
	x_offset_13d <= x_offset_12d;
	x_offset_14d <= x_offset_13d;
	x_offset_15d <= x_offset_14d;
	x_offset_16d <= x_offset_15d;
	x_offset_17d <= x_offset_16d;
	x_offset_18d <= x_offset_17d;
	x_offset_19d <= x_offset_18d;
	x_offset_20d <= x_offset_19d;
	x_offset_21d <= x_offset_20d;
	x_offset_22d <= x_offset_21d;
	x_offset_23d <= x_offset_22d;
	x_offset_24d <= x_offset_23d;
	x_offset_25d <= x_offset_24d;
	x_offset_26d <= x_offset_25d;
	x_offset_27d <= x_offset_26d;

	y_offset_1d  <= cv_y_offset; 
	y_offset_2d  <= y_offset_1d;
	y_offset_3d  <= y_offset_2d;
	y_offset_4d  <= y_offset_3d;
	y_offset_5d  <= y_offset_4d;
	y_offset_6d  <= y_offset_5d;
	y_offset_7d  <= y_offset_6d;
	y_offset_8d  <= y_offset_7d;
	y_offset_9d  <= y_offset_8d;
	y_offset_10d <= y_offset_9d;
	y_offset_11d <= y_offset_10d;
	y_offset_12d <= y_offset_11d;
	y_offset_13d <= y_offset_12d;
	y_offset_14d <= y_offset_13d;
	y_offset_15d <= y_offset_14d;
	y_offset_16d <= y_offset_15d;
	y_offset_17d <= y_offset_16d;
	y_offset_18d <= y_offset_17d;
	y_offset_19d <= y_offset_18d;
	y_offset_20d <= y_offset_19d;
	y_offset_21d <= y_offset_20d;
	y_offset_22d <= y_offset_21d;
	y_offset_23d <= y_offset_22d;
	y_offset_24d <= y_offset_23d;
	y_offset_25d <= y_offset_24d;
	y_offset_26d <= y_offset_25d;
	y_offset_27d <= y_offset_26d;

	cvg_1d  <= cv_cvg;
	cvg_2d  <= cvg_1d;
	cvg_3d  <= cvg_2d;
	cvg_4d  <= cvg_3d;
	cvg_5d  <= cvg_4d;
	cvg_6d  <= cvg_5d;
	cvg_7d  <= cvg_6d;
	cvg_8d  <= cvg_7d;
	cvg_9d  <= cvg_8d;
	cvg_10d <= cvg_9d;
	cvg_11d <= cvg_10d;
	cvg_12d <= cvg_11d;
	cvg_13d <= cvg_12d;
	cvg_14d <= cvg_13d;
	cvg_15d <= cvg_14d;
	cvg_16d <= cvg_15d;
	cvg_17d <= cvg_16d;
	cvg_18d <= cvg_17d;
	cvg_19d <= cvg_18d;
	cvg_20d <= cvg_19d;
	cvg_21d <= cvg_20d;
	cvg_22d <= cvg_21d;
	cvg_23d <= cvg_22d;
	cvg_24d <= cvg_23d;
	cvg_25d <= cvg_24d;
	cvg_26d <= cvg_25d;

	mask_1d  <= cv_mask;
	mask_2d  <= mask_1d;
	mask_3d  <= mask_2d;
	mask_4d  <= mask_3d;
	mask_5d  <= mask_4d;
	mask_6d  <= mask_5d;
	mask_7d  <= mask_6d;
	mask_8d  <= mask_7d;
	mask_9d  <= mask_8d;
	mask_10d <= mask_9d;
	mask_11d <= mask_10d;
	mask_12d <= mask_11d;
	mask_13d <= mask_12d;
	mask_14d <= mask_13d;
	mask_15d <= mask_14d;
	mask_16d <= mask_15d;
	mask_17d <= mask_16d;
	mask_18d <= mask_17d;
	mask_19d <= mask_18d;
	mask_20d <= mask_19d;
	mask_21d <= mask_20d;
	mask_22d <= mask_21d;
	mask_23d <= mask_22d;
	mask_24d <= mask_23d;
	mask_25d <= mask_24d;
	mask_26d <= mask_25d;
	mask_27d <= mask_26d;
	mask_28d <= mask_27d;
	mask_29d <= mask_28d;
end

assign two_cyc = (cycle_type == 1);

assign st_span_st_r = st_span_23d;
assign st_span_st_g = st_span_23d;
assign st_span_st_b = st_span_23d;
assign st_span_st_a = st_span_23d;
assign st_span_st_z = two_cyc ? st_span_26d : st_span_25d;
assign st_span_tf   = st_span_21d;
assign st_span_cc   = st_span_23d;
assign st_span_bl   = two_cyc ? st_span_26d : st_span_25d;
assign st_span_ms   = st_span_11d;	// 3 before load, 4 before copy
					// 10 before 1 cyc, 12 before 2 cyc
assign d_r = d_15d;
assign d_g = d_14d;
assign d_b = d_13d;
assign d_a = d_12d;
assign d_z = two_cyc ? d_14d : d_13d;

assign x_offset_r = x_offset_24d;
assign x_offset_g = x_offset_24d;
assign x_offset_b = x_offset_24d;
assign x_offset_a = x_offset_24d;
assign x_offset_z = two_cyc ? x_offset_27d : x_offset_26d;

assign y_offset_r = y_offset_24d;
assign y_offset_g = y_offset_24d;
assign y_offset_b = y_offset_24d;
assign y_offset_a = y_offset_24d;
assign y_offset_z = two_cyc ? y_offset_27d : y_offset_26d;

assign cvg_cc = cvg_26d;

assign mask_bl = two_cyc ? mask_29d : mask_28d;

assign   rgb_dither = two_cyc ? dither_32d : dither_30d;
assign alpha_dither = two_cyc ? dither_27d : dither_26d;

endmodule // ep_cc