Reduce number of stages and target density

src/config.tcl

@@ -12,7 +12,7 @@
 
 # PL_TARGET_DENSITY - You can increase this if Global Placement fails with error GPL-0302.
 # Users have reported that values up to 0.8 worked well for them.
-set ::env(PL_TARGET_DENSITY) 0.77
+set ::env(PL_TARGET_DENSITY) 0.7
 
 # CLOCK_PERIOD - Increase this in case you are getting setup time violations.
 # The value is in nanoseconds, so 20ns == 50MHz.

src/tt_um_hpretl_tt06_tdc.v

@@ -22,7 +22,7 @@ module tt_um_hpretl_tt06_tdc (
     input  wire       rst_n     // Async to clk
 );
 
-  localparam N_DELAY = 256;
+  localparam N_DELAY = 192;
 
   // All output pins must be assigned. If not used, assign to 0.
   assign uio_out[7:0] = 8'b0;