module sysctrl_tb;
	reg clock;
	reg RSTB;
	reg power1, power2;

	wire gpio;
	wire [15:0] checkbits;
	wire [7:0] spivalue;
	wire [37:0] mprj_io;
	wire flash_csb;
	wire flash_clk;
	wire flash_io0;
	wire flash_io1;
	wire SDO;

	assign checkbits = mprj_io[31:16];
	assign spivalue  = mprj_io[15:8];

	// External clock is used by default.  Make this artificially fast for the
	// simulation.  Normally this would be a slow clock and the digital PLL
	// would be the fast clock.

	always #10 clock <= (clock === 1'b0);

	initial begin
		clock = 0;
	end

	initial begin
		$dumpfile("sysctrl.vcd");
		$dumpvars(0, sysctrl_tb);
		repeat (25) begin
			repeat (1000) @(posedge clock);
			$display("+1000 cycles");
		end
		$display("%c[1;31m",27);
		`ifdef GL
			$display ("Monitor: Timeout, Test Sysctrl (GL) Failed");
		`else
			$display ("Monitor: Timeout, Test Sysctrl (RTL) Failed");
		`endif
		 $display("%c[0m",27);
		$finish;
	end

	// Monitor
	initial begin
	    wait(checkbits == 16'hA040);
			`ifdef GL
            	$display("Monitor: Test Sysctrl (GL) Started");
			`else
			    $display("Monitor: Test Sysctrl (RTL) Started");
			`endif
	    wait(checkbits == 16'hA041);
            $display("   SPI value = 0x%x (should be 0x04)", spivalue);
            if(spivalue !== 32'h04) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA042);
            $display("   SPI value = 0x%x (should be 0x56)", spivalue);
            if(spivalue !== 32'h56) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA043);
            $display("   SPI value = 0x%x (should be 0x10)", spivalue);
            if(spivalue !== 32'h10) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA044);
            $display("   SPI value = 0x%x (should be 0x02)", spivalue);
            if(spivalue !== 32'h02) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA045);
            $display("   SPI value = 0x%x (should be 0x01)", spivalue);
            if(spivalue !== 32'h01) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA046);
            $display("   SPI value = 0x%x (should be 0xff)", spivalue);
            if(spivalue !== 32'hff) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA047);
            $display("   SPI value = 0x%x (should be 0xef)", spivalue);
            if(spivalue !== 32'hef) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA048);
            $display("   SPI value = 0x%x (should be 0xff)", spivalue);
            if(spivalue !== 32'hff) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA049);
            $display("   SPI value = 0x%x (should be 0x03)", spivalue);
            if(spivalue !== 32'h03) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA04a);
            $display("   SPI value = 0x%x (should be 0x12)", spivalue);
            if(spivalue !== 32'h12) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end
	    wait(checkbits == 16'hA04b);
            $display("   SPI value = 0x%x (should be 0x04)", spivalue);
            if(spivalue !== 32'h04) begin
                $display("Monitor: Test Sysctrl Failed");
                $finish;
            end

	    wait(checkbits == 16'hA090);
		 	`ifdef GL
            	$display("Monitor: Test Sysctrl (GL) Passed");
			`else
		        $display("Monitor: Test Sysctrl (RTL) Passed");
			`endif
            $finish;
	end

	initial begin
		RSTB <= 1'b0;
		#1000;
		RSTB <= 1'b1;	    // Release reset
		#2000;
	end

	initial begin		// Power-up sequence
		power1 <= 1'b0;
		power2 <= 1'b0;
		#200;
		power1 <= 1'b1;
		#200;
		power2 <= 1'b1;
	end

	always @(checkbits) begin
		#1 $display("GPIO state = %b ", checkbits);
	end

	wire VDD3V3;
	wire VDD1V8;
	wire VSS;
	
	assign VDD3V3 = power1;
	assign VDD1V8 = power2;
	assign VSS = 1'b0;

	assign mprj_io[3] = 1'b1;
	
	caravel uut (
		.vddio	  (VDD3V3),
		.vssio	  (VSS),
		.vdda	  (VDD3V3),
		.vssa	  (VSS),
		.vccd	  (VDD1V8),
		.vssd	  (VSS),
		.vdda1    (VDD3V3),
		.vdda2    (VDD3V3),
		.vssa1	  (VSS),
		.vssa2	  (VSS),
		.vccd1	  (VDD1V8),
		.vccd2	  (VDD1V8),
		.vssd1	  (VSS),
		.vssd2	  (VSS),
		.clock    (clock),
		.gpio     (gpio),
		.mprj_io  (mprj_io),
		.flash_csb(flash_csb),
		.flash_clk(flash_clk),
		.flash_io0(flash_io0),
		.flash_io1(flash_io1),
		.resetb	  (RSTB)
	);

	spiflash #(
		.FILENAME("sysctrl.hex")
	) spiflash (
		.csb(flash_csb),
		.clk(flash_clk),
		.io0(flash_io0),
		.io1(flash_io1),
		.io2(),			// not used
		.io3()			// not used
	);

endmodule