Implement RTC

hw/efinix_fpga/simulation/tbs/rtc_tb.sv

@@ -0,0 +1,117 @@
+`timescale 1ns/1ps
+
+module rtc_tb();
+
+logic r_clk_cpu;
+
+initial begin
+    r_clk_cpu <= '1;
+    forever begin
+        #125 r_clk_cpu <= ~r_clk_cpu;
+    end
+end
+
+logic reset, rwb, cs, addr, irq;
+logic [7:0] i_data, o_data;
+
+rtc u_rtc(
+    .clk(r_clk_cpu),
+    .reset(reset),
+    .rwb(rwb),
+    .cs(cs),
+    .addr(addr),
+    .i_data(i_data),
+    .o_data(o_data),
+    .irq(irq)
+);
+
+initial begin
+    do_reset();
+    set_increment(1);
+    set_threshold(7);
+    set_irq_threshold(2);
+    enable_rtc(3);
+    repeat (20) @(posedge r_clk_cpu);
+    $finish();
+end
+
+initial begin
+    $dumpfile("rtc_tb.vcd");
+    $dumpvars(0,rtc_tb);
+end
+
+task do_reset();
+    repeat (5) @(posedge r_clk_cpu);
+    reset = 1;
+    cs = 0;
+    rwb = 1;
+    addr = '0;
+    i_data = '0;
+    repeat (5) @(posedge r_clk_cpu);
+    reset = 0;
+    repeat (5) @(posedge r_clk_cpu);
+endtask
+
+/* These should be shared */
+task write_reg(input logic [4:0] _addr, input logic [7:0] _data);
+    @(negedge r_clk_cpu);
+    cs <= '1;
+    addr <= _addr;
+    rwb <= '0;
+    i_data <= '1;
+    @(posedge r_clk_cpu);
+    i_data <= _data;
+    @(negedge r_clk_cpu);
+    cs <= '0;
+    rwb <= '1;
+    @(posedge r_clk_cpu);
+endtask
+
+task read_reg(input logic [2:0] _addr, output logic [7:0] _data);
+    @(negedge r_clk_cpu);
+    cs <= '1;
+    addr <= _addr;
+    rwb <= '1;
+    i_data <= '1;
+    @(posedge r_clk_cpu);
+    _data <= o_data;
+    @(negedge r_clk_cpu);
+    cs <= '0;
+    rwb <= '1;
+    @(posedge r_clk_cpu);
+endtask
+
+task set_increment(input logic [31:0] _increment);
+    for (int i = 0; i < 4; i++) begin
+        write_reg(0, 8'h10 | i);
+        write_reg(1, _increment[8*i +: 8]);
+    end
+endtask
+
+task set_threshold(input logic [31:0] _threshold);
+    for (int i = 0; i < 4; i++) begin
+        write_reg(0, 8'h00 | i);
+        write_reg(1, _threshold[8*i +: 8]);
+    end
+endtask
+
+task set_irq_threshold(input logic [31:0] _increment);
+    for (int i = 0; i < 4; i++) begin
+        write_reg(0, 8'h20 | i);
+        write_reg(1, _increment[8*i +: 8]);
+    end
+endtask
+
+task enable_rtc(input logic [7:0] _ctrl);
+    write_reg(0, 8'h30);
+    write_reg(1, _ctrl);
+endtask
+
+task read_output(output logic [31:0] _output);
+    for (int i = 0; i < 4; i++) begin
+        write_reg(0, 8'h30 | i);
+        read_reg(1, _output[8*i +: 8]);
+    end
+endtask
+
+endmodule