df_reg_ctrl.v

a H.264/AVC Baseline Decoder

				2'd3:buf2_3 <= {q3_MW,q2_MW,q1_MW,q0_MW};
			endcase
		//transpose update,"p":3,11,19,27,35,43  "q":21,30,38,46
		else if (buf2_transpose)
			begin 
				if (buf2_transpose_p)	//"p":3,11,19,27,35,43
					case (one_edge_counter_MW)
						2'd0:begin	buf2_0[7:0]   <= p3_MW;	buf2_1[7:0]   <= p2_MW;
									buf2_2[7:0]   <= p1_MW;	buf2_3[7:0]   <= p0_MW;	end
						2'd1:begin	buf2_0[15:8]  <= p3_MW;	buf2_1[15:8]  <= p2_MW;
									buf2_2[15:8]  <= p1_MW;	buf2_3[15:8]  <= p0_MW;	end
						2'd2:begin	buf2_0[23:16] <= p3_MW;	buf2_1[23:16] <= p2_MW;
									buf2_2[23:16] <= p1_MW;	buf2_3[23:16] <= p0_MW;	end
						2'd3:begin	buf2_0[31:24] <= p3_MW;	buf2_1[31:24] <= p2_MW;
									buf2_2[31:24] <= p1_MW;	buf2_3[31:24] <= p0_MW;	end
					endcase
				else					//"q":21,30,38,46
					case (one_edge_counter_MW)
						2'd0:begin	buf2_0[7:0]   <= q0_MW;	buf2_1[7:0]   <= q1_MW;
									buf2_2[7:0]   <= q2_MW;	buf2_3[7:0]   <= q3_MW;	end
						2'd1:begin	buf2_0[15:8]  <= q0_MW;	buf2_1[15:8]  <= q1_MW;
									buf2_2[15:8]  <= q2_MW;	buf2_3[15:8]  <= q3_MW;	end
						2'd2:begin	buf2_0[23:16] <= q0_MW;	buf2_1[23:16] <= q1_MW;
									buf2_2[23:16] <= q2_MW;	buf2_3[23:16] <= q3_MW;	end
						2'd3:begin	buf2_0[31:24] <= q0_MW;	buf2_1[31:24] <= q1_MW;
									buf2_2[31:24] <= q2_MW;	buf2_3[31:24] <= q3_MW;	end
					endcase
			end	
	//------------------------------------------------------
	//buf3
	//------------------------------------------------------
	wire buf3_no_transpose;	//buf3 updated without transpose
	wire buf3_transpose;		//buf3 updated after   transpose
	wire buf3_transpose_p;	//buf3 transpose and buf1 stores "p" position pixels
	assign buf3_no_transpose = (DF_edge_counter_MW == 6'd3  || DF_edge_counter_MW == 6'd19);
	assign buf3_transpose = (	DF_edge_counter_MW == 6'd7  || 
		DF_edge_counter_MW == 6'd11 || DF_edge_counter_MW == 6'd23 || DF_edge_counter_MW == 6'd27 || 
		DF_edge_counter_MW == 6'd25 || DF_edge_counter_MW == 6'd35 || DF_edge_counter_MW == 6'd43);
	assign buf3_transpose_p = (DF_edge_counter_MW == 6'd7  || DF_edge_counter_MW == 6'd23);  
	always @ (posedge gclk_DF or negedge reset_n)
		if (reset_n == 1'b0)
			begin 
				buf3_0 <= 0;	buf3_1 <= 0;	buf3_2 <= 0;	buf3_3 <= 0;
			end
		//no transpose update,always "q" position (right or down of the edge to be filtered)
		else if (buf3_no_transpose)
			case (one_edge_counter_MW)
				2'd0:buf3_0 <= {q3_MW,q2_MW,q1_MW,q0_MW};
				2'd1:buf3_1 <= {q3_MW,q2_MW,q1_MW,q0_MW};
				2'd2:buf3_2 <= {q3_MW,q2_MW,q1_MW,q0_MW};
				2'd3:buf3_3 <= {q3_MW,q2_MW,q1_MW,q0_MW};
			endcase
		//transpose update,"p":7,23  "q":11,25,27,35,43
		else if (buf3_transpose)
			begin 
				if (buf3_transpose_p)	//"p":7,23
					case (one_edge_counter_MW)
						2'd0:begin	buf3_0[7:0]   <= p3_MW;	buf3_1[7:0]   <= p2_MW;
									buf3_2[7:0]   <= p1_MW;	buf3_3[7:0]   <= p0_MW;	end
						2'd1:begin	buf3_0[15:8]  <= p3_MW;	buf3_1[15:8]  <= p2_MW;
									buf3_2[15:8]  <= p1_MW;	buf3_3[15:8]  <= p0_MW;	end
						2'd2:begin	buf3_0[23:16] <= p3_MW;	buf3_1[23:16] <= p2_MW;
									buf3_2[23:16] <= p1_MW;	buf3_3[23:16] <= p0_MW;	end
						2'd3:begin	buf3_0[31:24] <= p3_MW;	buf3_1[31:24] <= p2_MW;
									buf3_2[31:24] <= p1_MW;	buf3_3[31:24] <= p0_MW;	end
					endcase
				else					//"q":11,25,35,43
					case (one_edge_counter_MW)
						2'd0:begin	buf3_0[7:0]   <= q0_MW;	buf3_1[7:0]   <= q1_MW;
									buf3_2[7:0]   <= q2_MW;	buf3_3[7:0]   <= q3_MW;	end
						2'd1:begin	buf3_0[15:8]  <= q0_MW;	buf3_1[15:8]  <= q1_MW;
									buf3_2[15:8]  <= q2_MW;	buf3_3[15:8]  <= q3_MW;	end
						2'd2:begin	buf3_0[23:16] <= q0_MW;	buf3_1[23:16] <= q1_MW;
									buf3_2[23:16] <= q2_MW;	buf3_3[23:16] <= q3_MW;	end
						2'd3:begin	buf3_0[31:24] <= q0_MW;	buf3_1[31:24] <= q1_MW;
									buf3_2[31:24] <= q2_MW;	buf3_3[31:24] <= q3_MW;	end
					endcase
			end
	//------------------------------------------------------
	//T0:always updated after transpose,always "p" position
	//------------------------------------------------------
	wire t0_transpose;		//t0 updated after transpose
	assign t0_transpose = (
	DF_edge_counter_MW == 6'd4  || DF_edge_counter_MW == 6'd8  || DF_edge_counter_MW == 6'd12 || DF_edge_counter_MW == 6'd36 || 
	DF_edge_counter_MW == 6'd44 || DF_edge_counter_MW == 6'd15 || DF_edge_counter_MW == 6'd20 || DF_edge_counter_MW == 6'd24 || 
	DF_edge_counter_MW == 6'd28 || DF_edge_counter_MW == 6'd31 || DF_edge_counter_MW == 6'd39 || DF_edge_counter_MW == 6'd47);

	always @ (posedge gclk_DF or negedge reset_n)
		if (reset_n == 1'b0)
			begin 
				t0_0 <= 0;	t0_1 <= 0;	t0_2 <= 0;	t0_3 <= 0;
			end
		//always transpose update for "p" position
		else if (t0_transpose)
			case (one_edge_counter_MW)
				2'd0:begin	t0_0[7:0]   <= p3_MW;	t0_1[7:0]   <= p2_MW;
							t0_2[7:0]   <= p1_MW;	t0_3[7:0]   <= p0_MW;	end
				2'd1:begin	t0_0[15:8]  <= p3_MW;	t0_1[15:8]  <= p2_MW;
							t0_2[15:8]  <= p1_MW;	t0_3[15:8]  <= p0_MW;	end
				2'd2:begin	t0_0[23:16] <= p3_MW;	t0_1[23:16] <= p2_MW;
							t0_2[23:16] <= p1_MW;	t0_3[23:16] <= p0_MW;	end
				2'd3:begin	t0_0[31:24] <= p3_MW;	t0_1[31:24] <= p2_MW;
							t0_2[31:24] <= p1_MW;	t0_3[31:24] <= p0_MW;	end
			endcase
	//------------------------------------------------------
	//T1:always updated after transpose
	//------------------------------------------------------
	wire t1_transpose;		//t1 updated after   transpose
	wire t1_transpose_q;	//t1 transpose and t1 stores "q" position pixels
	assign t1_transpose = (
	DF_edge_counter_MW == 6'd13 || DF_edge_counter_MW == 6'd37 || DF_edge_counter_MW == 6'd45 || DF_edge_counter_MW == 6'd9  || 
	DF_edge_counter_MW == 6'd21 || DF_edge_counter_MW == 6'd25 || DF_edge_counter_MW == 6'd29 || DF_edge_counter_MW == 6'd31 || 
	DF_edge_counter_MW == 6'd39 || DF_edge_counter_MW == 6'd47);
	
	assign t1_transpose_q = (DF_edge_counter_MW == 6'd31 || DF_edge_counter_MW == 6'd39 || 
							 DF_edge_counter_MW == 6'd47);
	always @ (posedge gclk_DF or negedge reset_n)
		if (reset_n == 1'b0)
			begin 
				t1_0 <= 0;	t1_1 <= 0;	t1_2 <= 0;	t1_3 <= 0;
			end
		else if (t1_transpose && !t1_transpose_q)	//t1 transpose "p"
			case (one_edge_counter_MW)
				2'd0:begin	t1_0[7:0]   <= p3_MW;	t1_1[7:0]   <= p2_MW;
							t1_2[7:0]   <= p1_MW;	t1_3[7:0]   <= p0_MW;	end
				2'd1:begin	t1_0[15:8]  <= p3_MW;	t1_1[15:8]  <= p2_MW;
							t1_2[15:8]  <= p1_MW;	t1_3[15:8]  <= p0_MW;	end
				2'd2:begin	t1_0[23:16] <= p3_MW;	t1_1[23:16] <= p2_MW;
							t1_2[23:16] <= p1_MW;	t1_3[23:16] <= p0_MW;	end
				2'd3:begin	t1_0[31:24] <= p3_MW;	t1_1[31:24] <= p2_MW;
							t1_2[31:24] <= p1_MW;	t1_3[31:24] <= p0_MW;	end
			endcase
		else if (t1_transpose)						//t1 transpose "q"
			case (one_edge_counter_MW)
				2'd0:begin	t1_0[7:0]   <= q0_MW;	t1_1[7:0]   <= q1_MW;
							t1_2[7:0]   <= q2_MW;	t1_3[7:0]   <= q3_MW;	end
				2'd1:begin	t1_0[15:8]  <= q0_MW;	t1_1[15:8]  <= q1_MW;
							t1_2[15:8]  <= q2_MW;	t1_3[15:8]  <= q3_MW;	end
				2'd2:begin	t1_0[23:16] <= q0_MW;	t1_1[23:16] <= q1_MW;
							t1_2[23:16] <= q2_MW;	t1_3[23:16] <= q3_MW;	end
				2'd3:begin	t1_0[31:24] <= q0_MW;	t1_1[31:24] <= q1_MW;
							t1_2[31:24] <= q2_MW;	t1_3[31:24] <= q3_MW;	end
			endcase
	//--------------------------------------------------------------------
	//T2:only used after filter edge 18/34/42 to update mbAddrB of left MB
	//-------------------------------------------------------------------- 
	wire t2_wr;
	assign t2_wr = ((mb_num_h_DF != 0 && mb_num_v_DF != 4'd8) && 
	(DF_edge_counter_MW == 6'd18 || DF_edge_counter_MW == 6'd34 || DF_edge_counter_MW == 6'd42));
	always @ (posedge gclk_DF or negedge reset_n)
		if (reset_n == 1'b0)
			begin
				t2_0 <= 0;	t2_1 <= 0;	t2_2 <= 0;	t2_3 <= 0;
			end
		else if (t2_wr)
			case (one_edge_counter_MW)
				2'd0:begin	t2_0[7:0]   <= p3_MW;	t2_1[7:0]   <= p2_MW;
							t2_2[7:0]   <= p1_MW;	t2_3[7:0]   <= p0_MW;	end
				2'd1:begin	t2_0[15:8]  <= p3_MW;	t2_1[15:8]  <= p2_MW;
							t2_2[15:8]  <= p1_MW;	t2_3[15:8]  <= p0_MW;	end
				2'd2:begin	t2_0[23:16] <= p3_MW;	t2_1[23:16] <= p2_MW;
							t2_2[23:16] <= p1_MW;	t2_3[23:16] <= p0_MW;	end
				2'd3:begin	t2_0[31:24] <= p3_MW;	t2_1[31:24] <= p2_MW;
							t2_2[31:24] <= p1_MW;	t2_3[31:24] <= p0_MW;	end
			endcase
endmodule