From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Fri, 8 Jun 2012 15:54:03 +0000 (+0200)
Subject: actorlib: generator-based generic simulation actor
X-Git-Tag: 24jan2021_ls180~2099^2~936
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=910c7806cf619a501ff2d09f87e4fda6beee1de3;p=litex.git

actorlib: generator-based generic simulation actor
---

diff --git a/examples/dataflow_sim.py b/examples/dataflow_sim.py
new file mode 100644
index 00000000..3426a4fc
--- /dev/null
+++ b/examples/dataflow_sim.py
@@ -0,0 +1,33 @@
+import networkx as nx
+
+from migen.fhdl.structure import *
+from migen.flow.actor import *
+from migen.flow.network import *
+from migen.actorlib.sim import *
+from migen.sim.generic import Simulator
+from migen.sim.icarus import Runner
+
+def source_gen():
+	for i in range(10):
+		print("Sending:  " + str(i))
+		yield Token("source", {"value": i})
+
+def sink_gen():
+	while True:
+		t = Token("sink")
+		yield t
+		print("Received: " + str(t.value["value"]))
+
+def main():
+	source = SimActor(source_gen(), ("source", Source, [("value", BV(32))]))
+	sink = SimActor(sink_gen(), ("sink", Sink, [("value", BV(32))]))
+	g = nx.MultiDiGraph()
+	add_connection(g, source, sink)
+	comp = CompositeActor(g)
+	def end_simulation(s):
+		s.interrupt = source.done
+	fragment = comp.get_fragment() + Fragment(sim=[end_simulation])
+	sim = Simulator(fragment, Runner())
+	sim.run()
+
+main()
diff --git a/migen/actorlib/sim.py b/migen/actorlib/sim.py
new file mode 100644
index 00000000..0792143f
--- /dev/null
+++ b/migen/actorlib/sim.py
@@ -0,0 +1,70 @@
+from migen.fhdl.structure import *
+from migen.flow.actor import *
+
+class Token:
+	def __init__(self, endpoint, value=None):
+		self.endpoint = endpoint
+		self.value = value
+
+# Generators yield None or a tuple of Tokens.
+# Tokens for Sink endpoints are pulled and the "value" field filled in.
+# Tokens for Source endpoints are pushed according to their "value" field.
+#
+# NB: the possibility to push several tokens at once is important to interact
+# with actors that only accept a group of tokens when all of them are available.
+class SimActor(Actor):
+	def __init__(self, generator, *endpoint_descriptions, **misc):
+		self.generator = generator
+		self.active = [] # TODO: use set
+		self.done = False
+		super().__init__(*endpoint_descriptions, **misc)
+
+	def _process_transactions(self, s):
+		completed = []
+		for token in self.active:
+			ep = self.endpoints[token.endpoint]
+			if isinstance(ep, Sink):
+				if s.rd(ep.ack):
+					if s.rd(ep.stb):
+						token.value = s.multiread(ep.token)
+						completed.append(token)
+						s.wr(ep.ack, 0)
+				else:
+					s.wr(ep.ack, 1)
+			elif isinstance(ep, Source):
+				if s.rd(ep.stb):
+					if s.rd(ep.ack):
+						completed.append(token)
+						s.wr(ep.stb, 0)
+				else:
+					s.wr(ep.stb, 1)
+					s.multiwrite(ep.token, token.value)
+			else:
+				raise TypeError
+		for token in completed: # XXX
+			self.active.remove(token)
+	
+	def _next_transactions(self):
+		try:
+			transactions = next(self.generator)
+		except StopIteration:
+			self.done = True
+			transactions = None
+		if isinstance(transactions, Token):
+			self.active = [transactions]
+		elif isinstance(transactions, tuple) or isinstance(transactions, list):
+			self.active = list(transactions)
+		elif transactions is None:
+			self.active = []
+		else:
+			raise TypeError
+	
+	def do_simulation(self, s):
+		if not self.done:
+			if self.active:
+				self._process_transactions(s)
+			else:
+				self._next_transactions()
+		
+	def get_fragment(self):
+		return Fragment(sim=[self.do_simulation])