feat: Chip ROM auto generation with OpenLane 2

So we can generate the ROM while building the shuttle's GDS

rom/tt_um_chip_rom.v

@@ -0,0 +1,32 @@
+/*
+ * tt_um_chip_rom.v
+ *
+ * ROM module for Tiny Tapeout chips
+ *
+ * Author: Uri Shaked
+ */
+
+`default_nettype none
+
+module tt_um_chip_rom (
+	input  wire [7:0] ui_in,	// Dedicated inputs
+	output wire [7:0] uo_out,	// Dedicated outputs
+	input  wire [7:0] uio_in,	// IOs: Input path
+	output wire [7:0] uio_out,// IOs: Output path
+	output wire [7:0] uio_oe,	// IOs: Enable path (active high: 0=input, 1=output)
+	input  wire       ena,
+	input  wire       clk,
+	input  wire       rst_n
+);
+
+	reg [7:0] rom_data [0:255];
+
+  initial begin
+		$readmemh("rom.vmem", rom_data);
+	end
+	
+	assign uo_out  = rom_data[ui_in];
+	assign uio_out = 8'h00;
+	assign uio_oe  = 8'h00;
+
+endmodule // tt_um_chip_rom