lasmibus/crossbar: better switching policy

m-labs · Jun 15, 2013 · 6d6d232 · 6d6d232
1 parent ac2cde0
commit 6d6d232
Showing 1 changed file with 2 additions and 5 deletions.
diff --git a/migen/bus/lasmibus.py b/migen/bus/lasmibus.py
@@ -65,14 +65,11 @@ def __init__(self, controllers, nmasters, cba_shift):
 				bank = getattr(controller, "bank"+str(nb))
 
 				# arbitrate
-				rr = roundrobin.RoundRobin(nmasters, roundrobin.SP_CE)
+				rr = roundrobin.RoundRobin(nmasters, roundrobin.SP_WITHDRAW)
 				self.submodules += rr
 				bank_selected = [cs & (ba == nb) for cs, ba in zip(controller_selected, m_ba)]
 				bank_requested = [bs & master.stb for bs, master in zip(bank_selected, self.masters)]
-				self.comb += [
-					rr.request.eq(Cat(*bank_requested)),
-					rr.ce.eq(~bank.stb | bank.ack)
-				]
+				self.comb += rr.request.eq(Cat(*bank_requested)),
 
 				# route requests
 				self.comb += [