Move Dcache port creation from LSQUnit to LSQ in order to support Ron's recent changes, and using the O3CPU in SMT mode.

src/cpu/o3/lsq.hh:
    Update to have LSQ work with only one dcache port for all LSQ Units.  LSQ has the dcache port, and the LSQ Units must tell the LSQ if the cache has become blocked.
src/cpu/o3/lsq_impl.hh:
    Updates to have the LSQ work with only one dcache port for all LSQUnits.
src/cpu/o3/lsq_unit.hh:
src/cpu/o3/lsq_unit_impl.hh:
    Update for LSQ to create dcache port instead of LSQUnits.  Now LSQUnits are given the dcache port from the LSQ, and also must check the LSQ if the cache is blocked prior to accessing the cache.

--HG--
extra : convert_revision : 2708adbf323f4e7647dc0c1e31ef5bb4596b89f8

1 files changed, 57 insertions, 2 deletions

diff --git a/src/cpu/o3/lsq.hh b/src/cpu/o3/lsq.hh
index d5890950f..190734dc2 100644
--- a/src/cpu/o3/lsq.hh
+++ b/src/cpu/o3/lsq.hh
@@ -70,7 +70,7 @@ class LSQ {
      *  to work.  For now it just returns the port from one of the
      *  threads.
      */
-    Port *getDcachePort() { return thread[0].getDcachePort(); }
+    Port *getDcachePort() { return &dcachePort; }
 
     /** Sets the pointer to the list of active threads. */
     void setActiveThreads(std::list<unsigned> *at_ptr);
@@ -258,6 +258,15 @@ class LSQ {
     bool willWB(unsigned tid)
     { return thread[tid].willWB(); }
 
+    /** Returns if the cache is currently blocked. */
+    bool cacheBlocked()
+    { return retryTid != -1; }
+
+    /** Sets the retry thread id, indicating that one of the LSQUnits
+     * tried to access the cache but the cache was blocked. */
+    void setRetryTid(int tid)
+    { retryTid = tid; }
+
     /** Debugging function to print out all instructions. */
     void dumpInsts();
     /** Debugging function to print out instructions from a specific thread. */
@@ -274,7 +283,49 @@ class LSQ {
     template <class T>
     Fault write(RequestPtr req, T &data, int store_idx);
 
-  private:
+    /** DcachePort class for this LSQ.  Handles doing the
+     * communication with the cache/memory.
+     */
+    class DcachePort : public Port
+    {
+      protected:
+        /** Pointer to LSQ. */
+        LSQ *lsq;
+
+      public:
+        /** Default constructor. */
+        DcachePort(LSQ *_lsq)
+            : lsq(_lsq)
+        { }
+
+      protected:
+        /** Atomic version of receive.  Panics. */
+        virtual Tick recvAtomic(PacketPtr pkt);
+
+        /** Functional version of receive.  Panics. */
+        virtual void recvFunctional(PacketPtr pkt);
+
+        /** Receives status change.  Other than range changing, panics. */
+        virtual void recvStatusChange(Status status);
+
+        /** Returns the address ranges of this device. */
+        virtual void getDeviceAddressRanges(AddrRangeList &resp,
+                                            AddrRangeList &snoop)
+        { resp.clear(); snoop.clear(); }
+
+        /** Timing version of receive.  Handles writing back and
+         * completing the load or store that has returned from
+         * memory. */
+        virtual bool recvTiming(PacketPtr pkt);
+
+        /** Handles doing a retry of the previous send. */
+        virtual void recvRetry();
+    };
+
+    /** D-cache port. */
+    DcachePort dcachePort;
+
+  protected:
     /** The LSQ policy for SMT mode. */
     LSQPolicy lsqPolicy;
 
@@ -303,6 +354,10 @@ class LSQ {
 
     /** Number of Threads. */
     unsigned numThreads;
+
+    /** The thread id of the LSQ Unit that is currently waiting for a
+     * retry. */
+    int retryTid;
 };
 
 template <class Impl>