flow: network

examples/dataflow.py

@@ -1,22 +1,23 @@
+import networkx as nx
+
 from migen.fhdl import verilog 
 from migen.flow.ala import *
 from migen.flow.plumbing import *
+from migen.flow.network import *
+
+def get_actor_fragments(*actors):
+	return sum([a.get_control_fragment() + a.get_process_fragment() for a in actors], Fragment())
 
 act = Adder(32)
-comb = Combinator(act.operands, ["a"], ["b"])
+comb = Combinator(act.operands.template(), ["a"], ["b"])
 outbuf = Buffer(act.result.template())
-frag = get_actor_fragments(act, comb, outbuf)
 
-stb_a = comb.sinks[0].stb
+g = nx.MultiDiGraph()
-ack_a = comb.sinks[0].ack
+g.add_nodes_from([act, comb, outbuf])
-stb_b = comb.sinks[1].stb
+add_connection(g, comb, act)
-ack_b = comb.sinks[1].ack
+add_connection(g, act, outbuf)
-stb_a.name = "stb_a_i"
+c = CompositeActor(g)
-ack_a.name = "ack_a_o"
+
-stb_b.name = "stb_b_i"
+frag = c.get_control_fragment() + c.get_process_fragment()
-ack_b.name = "stb_b_o"
+
-a = comb.ins[0].a
+print(verilog.convert(frag))
-b = comb.ins[1].b
-a.name = "a"
-b.name = "b"
-print(verilog.convert(frag, ios={stb_a, ack_a, stb_b, ack_b, a, b}))

migen/corelogic/record.py

@@ -73,3 +73,6 @@ class Record:
 			elif isinstance(e, Record):
 				l += e.flatten()
 		return l
+	
+	def __repr__(self):
+		return repr(self.template())

migen/flow/actor.py

@@ -20,11 +20,25 @@ class SchedulingModel:
 			raise AttributeError
 
 class Endpoint:
-	def __init__(self, actor, token):
+	def __init__(self, token):
-		self.actor = actor
 		self.token = token
 		self.stb = Signal()
 		self.ack = Signal()
+	
+	def __hash__(self):
+		return id(self)
+		
+	def __repr__(self):
+		return "<Endpoint " + str(self.token) + ">"
+
+
+class Sink(Endpoint):
+	def __repr__(self):
+		return "<Sink " + str(self.token) + ">"
+
+class Source(Endpoint):
+	def __repr__(self):
+		return "<Source " + str(self.token) + ">"
 
 def _control_fragment_comb(stb_i, ack_o, stb_o, ack_i):
 	return Fragment([stb_o.eq(stb_i), ack_o.eq(ack_i)])
@@ -71,28 +85,47 @@ def _control_fragment_pipe(latency, stb_i, ack_o, stb_o, ack_i, pipe_ce):
 	return Fragment(comb, sync)
 
 class Actor:
-	def __init__(self, scheduling_model, sinks, sources):
+	def __init__(self, scheduling_model, sinks=None, sources=None, endpoints=None):
 		self.scheduling_model = scheduling_model
-		if isinstance(sinks, list):
+		if endpoints is None:
-			self.sinks = [Endpoint(self, sink) for sink in sinks]
+			if isinstance(sinks, list):
+				self.endpoints = [Sink(sink) for sink in sinks]
+			else:
+				self.endpoints = [Sink(sinks)]
+			if isinstance(sources, list):
+				self.endpoints += [Source(source) for source in sources]
+			else:
+				self.endpoints.append(Source(sources))
 		else:
-			self.sinks = [Endpoint(self, sinks)]
+			self.endpoints = endpoints
-		if isinstance(sources, list):
-			self.sources = [Endpoint(self, source) for source in sources]
-		else:
-			self.sources = [Endpoint(self, sources)]
 		if self.scheduling_model.model == SchedulingModel.SEQUENTIAL:
 			self.trigger = Signal()
 		elif self.scheduling_model.model == SchedulingModel.PIPELINE:
 			self.pipe_ce = Signal()
 	
+	def sinks(self):
+		return [x for x in self.endpoints if isinstance(x, Sink)]
+
+	def sources(self):
+		return [x for x in self.endpoints if isinstance(x, Source)]
+		
 	def get_control_fragment(self):
-		if len(self.sinks) != 1 or len(self.sources) != 1:
+		if len(self.endpoints) != 2:
+			raise ValueError("Actors with automatic control fragment must have exactly two endpoints.")
+		if isinstance(self.endpoints[0], Sink):
+			assert(isinstance(self.endpoints[1], Source))
+			sink = self.endpoints[0]
+			source = self.endpoints[1]
+		elif isinstance(self.endpoints[0], Source):
+			assert(isinstance(self.endpoints[1], Sink))
+			sink = self.endpoints[1]
+			source = self.endpoints[0]
+		else:
 			raise ValueError("Actors with automatic control fragment must have one sink and one source. Consider using plumbing actors.")
-		stb_i = self.sinks[0].stb
+		stb_i = sink.stb
-		ack_o = self.sinks[0].ack
+		ack_o = sink.ack
-		stb_o = self.sources[0].stb
+		stb_o = source.stb
-		ack_i = self.sources[0].ack
+		ack_i = source.ack
 		if self.scheduling_model.model == SchedulingModel.COMBINATORIAL:
 			return _control_fragment_comb(stb_i, ack_o, stb_o, ack_i)
 		elif self.scheduling_model.model == SchedulingModel.SEQUENTIAL:
@@ -104,6 +137,24 @@ class Actor:
 	
 	def get_process_fragment(self):
 		raise NotImplementedError("Actor classes must overload get_process_fragment")
+	
+	def __repr__(self):
+		return "<Actor " + repr(self.scheduling_model) + " " + repr(self.sinks()) + " " + repr(self.sources()) + ">"
 
-def get_actor_fragments(*actors):
+def get_conn_control_fragment(source, sink):
-	return sum([a.get_control_fragment() + a.get_process_fragment() for a in actors], Fragment())
+	assert(isinstance(source, Source))
+	assert(isinstance(sink, Sink))
+	comb = [
+		source.ack.eq(sink.ack),
+		sink.stb.eq(source.stb)
+	]
+	return Fragment(comb)
+	
+def get_conn_process_fragment(source, sink):
+	assert(isinstance(source, Source))
+	assert(isinstance(sink, Sink))
+	assert(sink.token.compatible(source.token))
+	sigs_source = source.token.flatten()
+	sigs_sink = sink.token.flatten()
+	comb = [Cat(*sigs_sink).eq(Cat(*sigs_source))]
+	return Fragment(comb)

migen/flow/network.py

@@ -0,0 +1,46 @@
+import networkx as nx
+
+from migen.flow.actor import *
+
+class CompositeActor(Actor):
+	def __init__(self, dfg):
+		self.dfg = dfg
+		# Internal unconnected endpoints become our endpoints. Determine them.
+		our_endpoints = []
+		for node in self.dfg:
+			endpoints = set(node.endpoints)
+			for u, v, d in self.dfg.in_edges([node], data=True):
+				endpoints.remove(d['sink'])
+			for u, v, d in self.dfg.out_edges([node], data=True):
+				endpoints.remove(d['source'])
+			our_endpoints += list(endpoints)
+		Actor.__init__(self,
+			SchedulingModel(SchedulingModel.DYNAMIC),
+			endpoints=our_endpoints)
+	
+	def get_control_fragment(self):
+		this = sum([get_conn_control_fragment(x[2]['source'], x[2]['sink'])
+			for x in self.dfg.edges(data=True)], Fragment())
+		others = sum([node.get_control_fragment() for node in self.dfg], Fragment())
+		return this + others
+	
+	def get_process_fragment(self):
+		this = sum([get_conn_process_fragment(x[2]['source'], x[2]['sink'])
+			for x in self.dfg.edges(data=True)], Fragment())
+		others = sum([node.get_process_fragment() for node in self.dfg], Fragment())
+		return this + others
+
+def add_connection(dfg, source_node, sink_node, source_ep=None, sink_ep=None):
+	if source_ep is None:
+		source_eps = source_node.sources()
+		assert(len(source_eps) == 1)
+		source_ep = source_eps[0]
+	if sink_ep is None:
+		sink_eps = sink_node.sinks()
+		assert(len(sink_eps) == 1)
+		sink_ep = sink_eps[0]
+	assert(isinstance(source_ep, Source))
+	assert(isinstance(sink_ep, Sink))
+	assert(source_ep in source_node.endpoints)
+	assert(sink_ep in sink_node.endpoints)
+	dfg.add_edge(source_node, sink_node, source=source_ep, sink=sink_ep)

migen/flow/plumbing.py

@@ -14,30 +14,34 @@ class Buffer(Actor):
 	def get_process_fragment(self):
 		sigs_d = self.d.flatten()
 		sigs_q = self.q.flatten()
-		sync = [Cat(*sigs_q).eq(Cat(*sigs_d))]
+		sync = [If(self.pipe_ce, Cat(*sigs_q).eq(Cat(*sigs_d)))]
 		return Fragment(sync=sync)
 
 class Combinator(Actor):
-	def __init__(self, destination, *subrecords):
+	def __init__(self, template, *subrecords):
-		self.ins = [destination.subrecord(*subr) for subr in subrecords]
+		self.destination = Record(template)
+		self.ins = [self.destination.subrecord(*subr) for subr in subrecords]
 		Actor.__init__(self,
 			SchedulingModel(SchedulingModel.COMBINATORIAL),
-			self.ins, destination)
+			self.ins, self.destination)
 
 	def get_process_fragment(self):
 		return Fragment() # nothing to do
 	
 	def get_control_fragment(self):
-		comb = [self.sources[0].stb.eq(optree('&', [sink.stb for sink in self.sinks]))]
+		source = self.sources()[0]
-		comb += [sink.ack.eq(self.sources[0].ack & self.sources[0].stb) for sink in self.sinks]
+		sinks = self.sinks()
+		comb = [source.stb.eq(optree('&', [sink.stb for sink in sinks]))]
+		comb += [sink.ack.eq(source.ack & source.stb) for sink in sinks]
 		return Fragment(comb)
 
 class Splitter(Actor):
-	def __init__(self, source, *subrecords):
+	def __init__(self, template, *subrecords):
-		self.outs = [source.subrecord(*subr) for subr in subrecords]
+		self.source = Record(template)
+		self.outs = [self.source.subrecord(*subr) for subr in subrecords]
 		Actor.__init__(self,
 			SchedulingModel(SchedulingModel.COMBINATORIAL),
-			source, self.outs)
+			self.source, self.outs)
 		
 	def get_process_fragment(self):
 		return Fragment() # nothing to do