From: Sebastien Bourdeauducq <sebastien@milkymist.org>
Date: Sat, 15 Jun 2013 14:51:09 +0000 (+0200)
Subject: lasmibus/crossbar: better switching policy
X-Git-Tag: 24jan2021_ls180~2099^2~555
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6d6d232cadd7e531e5566c1115a14c79e559b9eb;p=litex.git

lasmibus/crossbar: better switching policy
---

diff --git a/migen/bus/lasmibus.py b/migen/bus/lasmibus.py
index 201a9f71..be724ac1 100644
--- a/migen/bus/lasmibus.py
+++ b/migen/bus/lasmibus.py
@@ -65,14 +65,11 @@ class Crossbar(Module):
 				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 += [