diff --git a/techlibs/greenpak4/cells_sim.v b/techlibs/greenpak4/cells_sim.v
index 4ea576960..1234ce1b2 100644
--- a/techlibs/greenpak4/cells_sim.v
+++ b/techlibs/greenpak4/cells_sim.v
@@ -75,13 +75,44 @@ module GP_LFOSC(input PWRDN, output reg CLKOUT);
 	
 	initial CLKOUT = 0;
 	
+	//auto powerdown not implemented for simulation
+	//output dividers not implemented for simulation
+	
 	always begin
 		if(PWRDN)
-			clkout = 0;
+			CLKOUT = 0;
 		else begin
 			//half period of 1730 Hz
 			#289017;
-			clkout = ~clkout;
+			CLKOUT = ~CLKOUT;
+		end
+	end
+	
+endmodule
+
+module GP_RINGOSC(input PWRDN, output reg CLKOUT_PREDIV, output reg CLKOUT_FABRIC);
+	
+	parameter PWRDN_EN = 0;
+	parameter AUTO_PWRDN = 0;
+	parameter PRE_DIV = 1;
+	parameter FABRIC_DIV = 1;
+	
+	initial CLKOUT_PREDIV = 0;
+	initial CLKOUT_FABRIC = 0;
+	
+	//output dividers not implemented for simulation
+	//auto powerdown not implemented for simulation
+	
+	always begin
+		if(PWRDN) begin
+			CLKOUT_PREDIV = 0;
+			CLKOUT_FABRIC = 0;
+		end
+		else begin
+			//half period of 27 MHz
+			#18.518;
+			CLKOUT_PREDIV = ~CLKOUT_PREDIV;
+			CLKOUT_FABRIC = ~CLKOUT_FABRIC;
 		end
 	end
 	
@@ -144,3 +175,34 @@ module GP_SYSRESET(input RST);
 	//cannot simulate whole system reset
 	
 endmodule
+
+module GP_BANDGAP(output reg OK, output reg VOUT);
+	parameter AUTO_PWRDN = 1;
+	parameter CHOPPER_EN = 1;
+	parameter OUT_DELAY = 100;
+	
+	//cannot simulate mixed signal IP
+	
+endmodule
+
+
+module GP_POR(output reg RST_DONE);
+	parameter POR_TIME = 500;
+	
+	initial begin
+		RST_DONE = 0;
+		
+		if(POR_TIME == 4)
+			#4000;
+		else if(POR_TIME == 500)
+			#500000;
+		else begin
+			$display("ERROR: bad POR_TIME for GP_POR cell");
+			$finish;
+		end
+		
+		RST_DONE = 1;
+		
+	end
+	
+endmodule
diff --git a/techlibs/greenpak4/greenpak4_counters.cc b/techlibs/greenpak4/greenpak4_counters.cc
index 394f3dab1..7b5646bf2 100644
--- a/techlibs/greenpak4/greenpak4_counters.cc
+++ b/techlibs/greenpak4/greenpak4_counters.cc
@@ -248,8 +248,12 @@ void greenpak4_counters_worker(
 	if (cell->type != "$alu")
 		return;
 	
-	//A input is the count value. Check if it has COUNT_EXTRACT set
-	RTLIL::Wire* a_wire = sigmap(cell->getPort("\\A")).as_wire();
+	//A input is the count value. Check if it has COUNT_EXTRACT set.
+	//If it's not a wire, don't even try
+	auto port = sigmap(cell->getPort("\\A"));
+	if(!port.is_wire())
+		return;
+	RTLIL::Wire* a_wire = port.as_wire();
 	bool force_extract = false;
 	bool never_extract = false;
 	string count_reg_src = a_wire->attributes["\\src"].decode_string().c_str();