// SPDX-FileCopyrightText: 2020 Efabless Corporation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// SPDX-License-Identifier: Apache-2.0

`default_nettype wire

`timescale 1 ns / 1 ps

module usb2uart_tb;

	// Testbench uses a 48 MHz clock
	// Want to interface to 115200 baud UART
	parameter c_CLOCK_MHZ       = 48;
	parameter c_UART_SPEED      = 115200;

	parameter c_CLOCK_PERIOD_NS = 1000/c_CLOCK_MHZ;
	parameter c_CLKS_PER_BIT    = c_CLOCK_MHZ*1000000/c_UART_SPEED;
	parameter c_BIT_PERIOD      = c_CLKS_PER_BIT*c_CLOCK_PERIOD_NS;

	integer i;
	integer j;
	integer k;

    // Signals declaration
    reg clock;
    reg RSTB;
    reg power1, power2;
    reg CSB;
    wire gpio;
    wire [37:0] mprj_io;

	reg user_uart_rx;
/*
	wire mgmt_uart_tx;
	assign mgmt_uart_tx = mprj_io[6];
	//assign mprj_io[34] = mprj_io[6];
*/
	assign mprj_io[3] = (CSB == 1'b1) ? 1'b1 : 1'bz;

    // Signals Assignment
	assign mprj_io[34] = user_uart_rx;

    always #(c_CLOCK_PERIOD_NS/2) clock <= (clock === 1'b0);

    initial begin
        clock = 0;
    end

    `ifdef ENABLE_SDF
		initial begin
			$sdf_annotate("../../../sdf/user_proj_example.sdf", uut.mprj.mprj) ;
			$sdf_annotate("../../../mgmt_core_wrapper/sdf/DFFRAM.sdf", uut.soc.DFFRAM_0) ;
			$sdf_annotate("../../../mgmt_core_wrapper/sdf/mgmt_core.sdf", uut.soc.core) ;
			$sdf_annotate("../../../caravel/sdf/housekeeping.sdf", uut.housekeeping) ;
			$sdf_annotate("../../../caravel/sdf/chip_io.sdf", uut.padframe) ;
			$sdf_annotate("../../../caravel/sdf/mprj_logic_high.sdf", uut.mgmt_buffers.mprj_logic_high_inst) ;
			$sdf_annotate("../../../caravel/sdf/mprj2_logic_high.sdf", uut.mgmt_buffers.mprj2_logic_high_inst) ;
			$sdf_annotate("../../../caravel/sdf/mgmt_protect_hv.sdf", uut.mgmt_buffers.powergood_check) ;
			$sdf_annotate("../../../caravel/sdf/mgmt_protect.sdf", uut.mgmt_buffers) ;
			$sdf_annotate("../../../caravel/sdf/caravel_clocking.sdf", uut.clocking) ;
			$sdf_annotate("../../../caravel/sdf/digital_pll.sdf", uut.pll) ;
			$sdf_annotate("../../../caravel/sdf/xres_buf.sdf", uut.rstb_level) ;
			$sdf_annotate("../../../caravel/sdf/user_id_programming.sdf", uut.user_id_value) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_bidir_1[0] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_bidir_1[1] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_bidir_2[0] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_bidir_2[1] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_bidir_2[2] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[0] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[1] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[2] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[3] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[4] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[5] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[6] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[7] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[8] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[9] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1[10] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1a[0] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1a[1] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1a[2] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1a[3] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1a[4] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_1a[5] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[0] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[1] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[2] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[3] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[4] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[5] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[6] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[7] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[8] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[9] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[10] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[11] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[12] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[13] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[14] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_control_block.sdf", uut.\gpio_control_in_2[15] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.\gpio_defaults_block_0[0] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.\gpio_defaults_block_0[1] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.\gpio_defaults_block_2[0] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.\gpio_defaults_block_2[1] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.\gpio_defaults_block_2[2] ) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_5) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_6) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_7) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_8) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_9) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_10) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_11) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_12) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_13) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_14) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_15) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_16) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_17) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_18) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_19) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_20) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_21) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_22) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_23) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_24) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_25) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_26) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_27) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_28) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_29) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_30) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_31) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_32) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_33) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_34) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_35) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_36) ;
			$sdf_annotate("../../../caravel/sdf/gpio_defaults_block.sdf", uut.gpio_defaults_block_37) ;
		end
	`endif

    initial begin
        $dumpfile("usb2uart.vcd");
        $dumpvars(0, usb2uart_tb);
		`ifdef GL
		$monitor( "io_in[34]: 0x%x", uut.mprj.mprj.io_in[34] );
		`else
		$monitor( "usb2uart.in_data: 0x%x", uut.mprj.mprj.usb2uart.in_data );
		`endif
        // Repeat cycles of 1000 clock edges as needed to complete testbench
        repeat (50) begin
            repeat (1000) @(posedge clock);
        end
		$error ("Monitor: Timeout, Test Project USB Failed");
		//$fatal(1);
		$finish;
    end

	// Write a byte to RX pin
	task UART_WRITE_RX_AND_RCV;
		input [7:0] i_Data;
		integer     ii;
	begin
		`ifdef GL
		`else
		//wait(uut.mprj.mprj.usb2uart.in_ready == 1);
		`endif
		// Write Start Bit
		#(c_BIT_PERIOD) user_uart_rx <= 1'b0;

		// Write Data
		for (ii=0; ii<8; ii=ii+1)
		begin
			#(c_BIT_PERIOD) user_uart_rx <= i_Data[ii];
		end

		// Write Stop Bit
		#(c_BIT_PERIOD) user_uart_rx <= 1'b1;

		`ifdef GL
		//wait(uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tvalid_reg == 1);
		`else
		//@(posedge uut.mprj.mprj.usb2uart.in_valid);
		//wait(uut.mprj.mprj.usb2uart.in_valid == 1);
		`endif
		#(c_BIT_PERIOD);
	end
	endtask

	initial begin		
		// Exercise Rx
		j=0;
		for (i=0; i<8; i=i+1) begin
			UART_WRITE_RX_AND_RCV(i);
			`ifdef GL
			k[7:0] = {
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[7] ,
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[6] ,
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[5] ,
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[4] ,
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[3] ,
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[2] ,
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[1] ,
				uut.mprj.mprj.\usb2uart.u_uart.uart_rx_inst.m_axis_tdata_reg[0] };
			`else
			k = uut.mprj.mprj.usb2uart.in_data;
			`endif

			if (k == i)
				j=j+1;
			else
				$error("RX Test Failed - Incorrect Byte Received 0x%x", k);
		end
		if (j == 8)
			$display("RX Test Passed - Correct Bytes Received");
		else
			;//$fatal(2);
		$finish;
	end

    // Reset Operation
    initial begin
        CSB <= 1'b1;		
        RSTB <= 1'b0;
        #2000;
        RSTB <= 1'b1;       	// Release reset
        #1_300_000;
        CSB <= 1'b0;		// Stop driving CSB
    end

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

    wire flash_csb;
    wire flash_clk;
    wire flash_io0;
    wire flash_io1;

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

    caravel uut (
        .vddio	  (VDD3V3),
		.vddio_2  (VDD3V3),
		.vssio	  (VSS),
		.vssio_2  (VSS),
		.vdda	  (VDD3V3),
		.vssa	  (VSS),
		.vccd	  (VDD1V8),
		.vssd	  (VSS),
		.vdda1    (VDD3V3),
		.vdda1_2  (VDD3V3),
		.vdda2    (VDD3V3),
		.vssa1	  (VSS),
		.vssa1_2  (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("usb2uart.hex")
    ) spiflash (
        .csb(flash_csb),
        .clk(flash_clk),
        .io0(flash_io0),
        .io1(flash_io1),
        .io2(),         // not used
        .io3()          // not used
    );

/*
	// Testbench UART
	tbuart tbuart (
		.ser_rx(mgmt_uart_tx)
	);
*/
endmodule
`default_nettype wire