diff --git a/py_gen/codegen.py b/py_gen/codegen.py
index 66e0454..fb2e48c 100644
--- a/py_gen/codegen.py
+++ b/py_gen/codegen.py
@@ -129,16 +129,8 @@
     util.render_template(out, 'common.py', ofclasses=ofclasses, version=version)
 
 def generate_const(out, name, version):
-    groups = {}
-    for (group, idents) in of_g.identifiers_by_group.items():
-        items = []
-        for ident in idents:
-            info = of_g.identifiers[ident]
-            if version in info["values_by_version"]:
-                items.append((info["ofp_name"], info["values_by_version"][version]))
-        if items:
-            groups[group] = items
-    util.render_template(out, 'const.py', version=version, groups=groups)
+    util.render_template(out, 'const.py', version=version,
+                         enums=of_g.ir[version].enums)
 
 def generate_instruction(out, name, version):
     ofclasses = [x for x in build_ofclasses(version)
diff --git a/py_gen/templates/const.py b/py_gen/templates/const.py
index ef09585..4567d56 100644
--- a/py_gen/templates/const.py
+++ b/py_gen/templates/const.py
@@ -36,10 +36,9 @@
 
 OFP_VERSION = ${version}
 
-:: for (group, idents) in sorted(groups.items()):
-::    idents.sort(key=lambda (ident, value): value)
-# Identifiers from group ${group}
-::    for (ident, value) in idents:
+:: for enum in sorted(enums, key=lambda enum: enum.name):
+# Identifiers from group ${enum.name}
+::    for (ident, value) in enum.values:
 ::        if version == 1 and ident.startswith('OFPP_'):
 ::        # HACK loxi converts these to 32-bit
 ${ident} = ${"%#x" % (value & 0xffff)}
@@ -48,9 +47,9 @@
 ::        #endif
 ::    #endfor
 
-::    if group not in blacklisted_map_groups:
-${group}_map = {
-::        for (ident, value) in idents:
+::    if enum.name not in blacklisted_map_groups:
+${enum.name}_map = {
+::        for (ident, value) in enum.values:
 ::            if ident in blacklisted_map_idents:
 ::                pass
 ::            elif version == 1 and ident.startswith('OFPP_'):