diff --git a/uncore/coherence.scala b/uncore/coherence.scala
index 5f70d81f..2c5c6edf 100644
--- a/uncore/coherence.scala
+++ b/uncore/coherence.scala
@@ -90,8 +90,8 @@ class ioTileLink extends Bundle {
   val xact_finish    = (new ioDecoupled) { new TransactionFinish() }.flip
 }
 
-trait CoherencePolicy {
-  def cpuCmdToRW( cmd: Bits): (Bool, Bool) = {
+object cpuCmdToRW {
+  def apply(cmd: Bits): (Bool, Bool) = {
     val store   = (cmd === M_XWR)
     val load    = (cmd === M_XRD)
     val amo     = cmd(3).toBool
@@ -101,6 +101,9 @@ trait CoherencePolicy {
   }
 }
 
+trait CoherencePolicy {
+}
+
 trait ThreeStateIncoherence extends CoherencePolicy {
   val tileInvalid :: tileClean :: tileDirty :: Nil = Enum(3){ UFix() }