module MDU(
input clk,rst,
input [2:0] mdu,
input [31:0] rdata1,rdata2,
output [63:0] mul_out,
output reg pc_ena,
output reg [31:0] hi,lo);
wire div_start,divu_start,div_busy,divu_busy,div_over,divu_over;
wire [63:0] mult_out,multu_out,div_out,divu_out;
assign mul_out = mult_out;
/*
1 mult
2 multu
3 div
4 divu
5 mthi
6 mtlo
*/
//assign pc_ena=1'b1;
always@(*)begin
case(mdu)
3'h3: pc_ena = div_over ||mdu!=3'h3;
3'h4: pc_ena = divu_over||mdu!=3'h4;
default:pc_ena = 1'b1;
endcase
end
assign div_start = mdu==3'h3&&!div_busy;
assign divu_start = mdu==3'h4&&!divu_busy;
always@(posedge clk or posedge rst)begin
if(rst) begin
hi<=32'b0;
lo<=32'b0;
end
else begin
case(mdu)
3'h1: {hi,lo} <= mult_out;
3'h2: {hi,lo} <= multu_out;
3'h3: {lo,hi} <= div_out;
3'h4: {lo,hi} <= divu_out;
3'h5: hi <= rdata1;
3'h6: lo <= rdata1;
endcase
end
end
mult_gen_0 multiplier(
.A(rdata1),
.B(rdata2),
.P(mult_out));
mult_gen_1 multiplier_unsigned(
.A(rdata1),
.B(rdata2),
.P(multu_out));
DIV DIV(
.dividend(rdata1),
.divisor(rdata2),
.clock(clk),
.reset(mdu!=3'h3),
.start(div_start),
.q(div_out[63:32]),
.r(div_out[31:0]),
.over(div_over),
.busy(div_busy));
DIVU DIVU(
.dividend(rdata1),
.divisor(rdata2),
.clock(clk),
.reset(mdu!=3'h4),
.start(divu_start),
.q(divu_out[63:32]),
.r(divu_out[31:0]),
.over(divu_over),
.busy(divu_busy));
endmodule
