pytholite/io: support token push

diff --git a/migen/pytholite/io.py b/migen/pytholite/io.py
index 2dfbf7710eef01ad501710b266ce589da1bda395..f0be3ca3108a22ceb91e13598b76aa8466309a03 100644 (file)
--- a/migen/pytholite/io.py
+++ b/migen/pytholite/io.py
@@ -1,7 +1,9 @@
 import ast
 
+from migen.fhdl.structure import *
 from migen.flow.actor import *
 from migen.actorlib.sim import *
+from migen.pytholite.fsm import *
 
 class Pytholite:
        def get_fragment(self):
@@ -14,15 +16,38 @@ def make_io_object(dataflow=None):
        if dataflow is None:
                return Pytholite()
        else:
-               return DFPytholite(dataflow)
+               return DFPytholite(*dataflow)
 
+def gen_df_io(compiler, to_model, from_model):
+       if len(to_model) == 1 or len(to_model) == 2:
+               epname = ast.literal_eval(to_model[0])
+               ep = compiler.ioo.endpoints[epname]
+       else:
+               raise TypeError("Token() takes 1 or 2 arguments")
+       
+       if len(to_model) == 1:
+               # token pull from sink
+               raise NotImplementedError # TODO
+       else:
+               # token push to source
+               if from_model:
+                       raise TypeError("Attempted to read from pushed token")
+               d = to_model[1]
+               if not isinstance(d, ast.Dict):
+                       raise NotImplementedError
+               state = []
+               for akey, value in zip(d.keys, d.values):
+                       key = ast.literal_eval(akey)
+                       signal = getattr(ep.token, key)
+                       state.append(signal.eq(compiler.ec.visit_expr(value)))
+               state += [
+                       ep.stb.eq(1),
+                       If(~ep.ack, AbstractNextState(state))
+               ]
+               return [state], [state]
 
 def gen_io(compiler, model, to_model, from_model):
-       print("model: " + str(model))
-       print("to_model:")
-       for arg in to_model:
-               print(ast.dump(arg))
-       print("from_model:")
-       for target, expr in from_model:
-               print(str(target) + " <= " + ast.dump(expr))
-       return [], []
+       if model == Token:
+               return gen_df_io(compiler, to_model, from_model)
+       else:
+               raise NotImplementedError