Add irq code tb

hw/efinix_fpga/simulation/tbs/interrupt_controller_code_tb.sv

@@ -0,0 +1,35 @@
+`timescale 1ns/1ps
+
+module interrupt_controller_code_tb();
+
+sim_top u_sim_top();
+
+always begin
+    if (
+        u_sim_top.w_cpu_addr == 16'h0 &&
+        u_sim_top.w_cpu_we == '1
+    ) begin
+        if (u_sim_top.w_cpu_data_from_cpu == 8'h6d) begin
+            $display("Good finish!");
+            $finish();
+        end else begin
+            $display("Bad finish!");
+            $finish_and_return(-1);
+        end
+    end
+    # 1;
+end
+
+initial begin
+    u_sim_top.u_dut.int_in = 0;
+    repeat (1000) @(posedge u_sim_top.r_clk_cpu);
+    u_sim_top.u_dut.int_in = 1;
+end
+
+initial begin
+    repeat (2000) @(posedge u_sim_top.r_clk_cpu);
+    $display("Timed out");
+    $finish_and_return(-1);
+end
+
+endmodule