diff --git a/tcl/package_ip.tcl b/tcl/package_ip.tcl
index 31e23e6..3e86088 100644
--- a/tcl/package_ip.tcl
+++ b/tcl/package_ip.tcl
@@ -30,6 +30,48 @@ proc SplitSub { str startword } {
 	}
 }
 
+# Gets all the values whose key starts with 'startword.*', returns a
+# dictionary with the same values, but the keys are instead '*'.
+#
+# EX: With the dictionary d = { param.foo one param.bar two biz three }
+#
+# Calling [GetSubValues $d "param"] would result in the dictionary:
+#
+# { foo one bar two }
+proc GetSubValues {map subcat} {
+	set res_map [dict create]
+
+	foreach {key val} $map {
+		set new_key [SplitSub $key $subcat]
+
+		if { $new_key != "" } {
+			dict append res_map $new_key $val
+		}
+	}
+
+	return $res_map
+}
+
+proc InterfaceAddParameters {iface params} {
+	foreach {param_name val} $params {
+		puts "Setting parameter $param_name"
+
+		ipx::add_bus_parameter $param_name $iface
+		set param [ipx::get_bus_parameters $param_name -of_objects $iface]
+		set_property value $val $param
+	}
+}
+
+proc InterfaceAddPortMaps {iface port_maps} {
+	foreach {logical_port physical_port} $port_maps {
+		puts "Mapping logical port $logical_port"
+
+		ipx::add_port_map $logical_port $iface
+		set port_map [ipx::get_port_maps $logical_port -of_objects $iface]
+		set_property physical_name $physical_port $port_map
+	}
+}
+
 # Parse the interface configuration and create a new interface
 # in the current core
 #
@@ -93,36 +135,11 @@ proc ParseInterfaceConf { iface_name iface_conf } {
 		set_property INTERFACE_MODE [dict get $iface_conf "MODE"] $iface
 	}
 
-	# Create user parameters
-	foreach {key val} $iface_conf {
-		set param_name [SplitSub $key "PARAMETER"]
+	set params [GetSubValues $iface_conf "PARAMETER"]
+	set port_maps [GetSubValues $iface_conf "PORT"]
 
-		if { $param_name == "" } {
-			continue
-		}
-
-		puts "Setting parameter $param_name"
-
-		ipx::add_bus_parameter $param_name $iface
-		set param [ipx::get_bus_parameters $param_name -of_objects $iface]
-		set_property value $val $param
-	}
-
-	# Create port mappings
-	foreach {key val} $iface_conf {
-		set logical_port [SplitSub $key "PORT"]
-		set physical_port $val
-
-		if { $logical_port == "" } {
-			continue
-		}
-		
-		puts "Mapping logical port $logical_port"
-
-		ipx::add_port_map $logical_port $iface
-		set port_map [ipx::get_port_maps $logical_port -of_objects $iface]
-		set_property physical_name $physical_port $port_map
-	}
+	InterfaceAddParameters $iface $params
+	InterfaceAddPortMaps $iface $port_maps
 }
 
 set gitroot [exec git rev-parse --show-toplevel]