From dd9a102a780b473ede794b8089b90a45b973c011 Mon Sep 17 00:00:00 2001
From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Fri, 16 Nov 2012 19:24:45 +0100
Subject: [PATCH] pytholite/io: support token push

---
 migen/pytholite/io.py | 43 ++++++++++++++++++++++++++++++++++---------
 1 file changed, 34 insertions(+), 9 deletions(-)

diff --git a/migen/pytholite/io.py b/migen/pytholite/io.py
index 2dfbf7710..f0be3ca31 100644
--- 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