5 files changed, 35 insertions, 20 deletions

diff --git a/src/mem/bridge.cc b/src/mem/bridge.cc
index ecaf6de04..855f39de3 100644
--- a/src/mem/bridge.cc
+++ b/src/mem/bridge.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2013 ARM Limited
+ * Copyright (c) 2011-2013, 2015 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
@@ -150,8 +150,20 @@ Bridge::BridgeSlavePort::recvTimingReq(PacketPtr pkt)
     DPRINTF(Bridge, "recvTimingReq: %s addr 0x%x\n",
             pkt->cmdString(), pkt->getAddr());
 
-    // we should not see a timing request if we are already in a retry
-    assert(!retryReq);
+    // sink inhibited packets without further action, also discard any
+    // packet that is not a read or a write
+    if (pkt->memInhibitAsserted() ||
+        !(pkt->isWrite() || pkt->isRead())) {
+        assert(!pkt->needsResponse());
+        pendingDelete.reset(pkt);
+        return true;
+    }
+
+    // we should not get a new request after committing to retry the
+    // current one, but unfortunately the CPU violates this rule, so
+    // simply ignore it for now
+    if (retryReq)
+        return false;
 
     DPRINTF(Bridge, "Response queue size: %d outresp: %d\n",
             transmitList.size(), outstandingResponses);
@@ -162,8 +174,7 @@ Bridge::BridgeSlavePort::recvTimingReq(PacketPtr pkt)
         retryReq = true;
     } else {
         // look at the response queue if we expect to see a response
-        bool expects_response = pkt->needsResponse() &&
-            !pkt->memInhibitAsserted();
+        bool expects_response = pkt->needsResponse();
         if (expects_response) {
             if (respQueueFull()) {
                 DPRINTF(Bridge, "Response queue full\n");
diff --git a/src/mem/bridge.hh b/src/mem/bridge.hh
index 6aebe5204..ad3585997 100644
--- a/src/mem/bridge.hh
+++ b/src/mem/bridge.hh
@@ -136,6 +136,12 @@ class Bridge : public MemObject
         unsigned int respQueueLimit;
 
         /**
+         * Upstream caches need this packet until true is returned, so
+         * hold it for deletion until a subsequent call
+         */
+        std::unique_ptr<Packet> pendingDelete;
+
+        /**
          * Is this side blocked from accepting new response packets.
          *
          * @return true if the reserved space has reached the set limit
diff --git a/src/mem/dram_ctrl.cc b/src/mem/dram_ctrl.cc
index 4bd83f761..abf570910 100644
--- a/src/mem/dram_ctrl.cc
+++ b/src/mem/dram_ctrl.cc
@@ -590,10 +590,8 @@ DRAMCtrl::recvTimingReq(PacketPtr pkt)
     DPRINTF(DRAM, "recvTimingReq: request %s addr %lld size %d\n",
             pkt->cmdString(), pkt->getAddr(), pkt->getSize());
 
-    // simply drop inhibited packets and clean evictions
-    if (pkt->memInhibitAsserted() ||
-        pkt->cmd == MemCmd::CleanEvict) {
-        DPRINTF(DRAM, "Inhibited packet or clean evict -- Dropping it now\n");
+    // sink inhibited packets without further action
+    if (pkt->memInhibitAsserted()) {
         pendingDelete.reset(pkt);
         return true;
     }
diff --git a/src/mem/dramsim2.cc b/src/mem/dramsim2.cc
index cd0f45b23..58227e06a 100644
--- a/src/mem/dramsim2.cc
+++ b/src/mem/dramsim2.cc
@@ -175,16 +175,18 @@ DRAMSim2::recvFunctional(PacketPtr pkt)
 bool
 DRAMSim2::recvTimingReq(PacketPtr pkt)
 {
-    // we should never see a new request while in retry
-    assert(!retryReq);
-
+    // sink inhibited packets without further action
     if (pkt->memInhibitAsserted()) {
-        // snooper will supply based on copy of packet
-        // still target's responsibility to delete packet
         pendingDelete.reset(pkt);
         return true;
     }
 
+    // we should not get a new request after committing to retry the
+    // current one, but unfortunately the CPU violates this rule, so
+    // simply ignore it for now
+    if (retryReq)
+        return false;
+
     // if we cannot accept we need to send a retry once progress can
     // be made
     bool can_accept = nbrOutstanding() < wrapper.queueSize();
diff --git a/src/mem/simple_mem.cc b/src/mem/simple_mem.cc
index 7e350feb6..639ccbe31 100644
--- a/src/mem/simple_mem.cc
+++ b/src/mem/simple_mem.cc
@@ -97,17 +97,15 @@ SimpleMemory::recvFunctional(PacketPtr pkt)
 bool
 SimpleMemory::recvTimingReq(PacketPtr pkt)
 {
+    // sink inhibited packets without further action
     if (pkt->memInhibitAsserted()) {
-        // snooper will supply based on copy of packet
-        // still target's responsibility to delete packet
         pendingDelete.reset(pkt);
         return true;
     }
 
-    // we should never get a new request after committing to retry the
-    // current one, the bus violates the rule as it simply sends a
-    // retry to the next one waiting on the retry list, so simply
-    // ignore it
+    // we should not get a new request after committing to retry the
+    // current one, but unfortunately the CPU violates this rule, so
+    // simply ignore it for now
     if (retryReq)
         return false;