diff --git a/src/mem/packet.cc b/src/mem/packet.cc
index e05783c..75dfb28 100644
--- a/src/mem/packet.cc
+++ b/src/mem/packet.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2016 ARM Limited
+ * Copyright (c) 2011-2017 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -95,6 +95,9 @@
      * dirty. */
     { SET5(IsWrite, IsRequest, IsEviction, HasData, FromCache),
             InvalidCmd, "WritebackClean" },
+    /* WriteClean - This allows a cache to write a dirty block to a memory
+       below without evicting its copy. */
+    { SET4(IsWrite, IsRequest, HasData, FromCache), InvalidCmd, "WriteClean" },
     /* CleanEvict */
     { SET3(IsRequest, IsEviction, FromCache), InvalidCmd, "CleanEvict" },
     /* SoftPFReq */
diff --git a/src/mem/packet.hh b/src/mem/packet.hh
index 0920f22..330e2ae 100644
--- a/src/mem/packet.hh
+++ b/src/mem/packet.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012-2016 ARM Limited
+ * Copyright (c) 2012-2017 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -88,6 +88,7 @@
         WriteResp,
         WritebackDirty,
         WritebackClean,
+        WriteClean,            // writes dirty data below without evicting
         CleanEvict,
         SoftPFReq,
         HardPFReq,