csr: use optree

diff --git a/migen/bus/csr.py b/migen/bus/csr.py
index 8e5af9a60204c0f3a8146f58bd721848cc938fe2..740fcb3021d7c102da2fcaaf5c19011652b789f7 100644 (file)
--- a/migen/bus/csr.py
+++ b/migen/bus/csr.py
@@ -1,4 +1,5 @@
 from migen.fhdl.structure import *
+from migen.corelogic.misc import optree
 from migen.bus.simple import Simple
 
 _desc = [
@@ -23,11 +24,10 @@ class Interconnect:
        
        def get_fragment(self):
                comb = []
-               rb = Constant(0, BV(8))
                for slave in self.slaves:
                        comb.append(slave.a_i.eq(self.master.a_o))
                        comb.append(slave.we_i.eq(self.master.we_o))
                        comb.append(slave.d_i.eq(self.master.d_o))
-                       rb = rb | slave.d_o
+               rb = optree('|', [slave.d_o for slave in self.slaves])
                comb.append(self.master.d_i.eq(rb))
                return Fragment(comb)