MIPS ISA runs 'hello world' in O3CPU ...

src/arch/mips/isa/base.isa:
    special case syscall disasembly... maybe give own instruction class?
src/arch/mips/isa/decoder.isa:
    add 'IsSerializeAfter' flag for syscall
src/cpu/o3/commit.hh:
    Add skidBuffer to commit
src/cpu/o3/commit_impl.hh:
    Use skidbuffer in MIPS ISA
src/cpu/o3/fetch_impl.hh:
    Print name out when there is a fault
src/cpu/o3/mips/cpu_impl.hh:
    change comment

--HG--
extra : convert_revision : d032549e07102bdd50aa09f044fce8de6f0239b5

6 files changed, 113 insertions, 24 deletions

diff --git a/src/arch/mips/isa/base.isa b/src/arch/mips/isa/base.isa
index f07b06e03..7c042f16f 100644
--- a/src/arch/mips/isa/base.isa
+++ b/src/arch/mips/isa/base.isa
@@ -79,21 +79,27 @@ output decoder {{
 
         ccprintf(ss, "%-10s ", mnemonic);
 
-        if(_numDestRegs > 0){
-            printReg(ss, _destRegIdx[0]);
+        // Need to find standard way to not print
+        // this info. Maybe add bool variable to
+        // class?
+        if (mnemonic != "syscall") {
+            if(_numDestRegs > 0){
+                printReg(ss, _destRegIdx[0]);
+            }
+
+            if(_numSrcRegs > 0) {
+                ss << ", ";
+                printReg(ss, _srcRegIdx[0]);
+            }
+
+            if(_numSrcRegs > 1) {
+                ss << ", ";
+                printReg(ss, _srcRegIdx[1]);
+            }
         }
 
-        if(_numSrcRegs > 0) {
-            ss << ", ";
-            printReg(ss, _srcRegIdx[0]);
-        }
-
-        if(_numSrcRegs > 1) {
-            ss << ", ";
-            printReg(ss, _srcRegIdx[1]);
-        }
-
-
+        // Should we define a separate inst. class
+        // just for two insts?
         if(mnemonic == "sll" || mnemonic == "sra"){
             ccprintf(ss,", %d",SA);
         }
diff --git a/src/arch/mips/isa/decoder.isa b/src/arch/mips/isa/decoder.isa
index 13f6f9712..d65e3eb94 100644
--- a/src/arch/mips/isa/decoder.isa
+++ b/src/arch/mips/isa/decoder.isa
@@ -133,7 +133,8 @@ decode OPCODE_HI default Unknown::unknown() {
                 format BasicOp {
                     0x2: movz({{ Rd = (Rt == 0) ? Rs : Rd; }});
                     0x3: movn({{ Rd = (Rt != 0) ? Rs : Rd; }});
-                    0x4: syscall({{ xc->syscall(R2); }}, IsNonSpeculative);
+                    0x4: syscall({{ xc->syscall(R2); }},
+                                 IsSerializeAfter, IsNonSpeculative);
                     0x7: sync({{ ; }}, IsMemBarrier);
                 }
 
diff --git a/src/cpu/o3/commit.hh b/src/cpu/o3/commit.hh
index cb83012f7..5caa317b3 100644
--- a/src/cpu/o3/commit.hh
+++ b/src/cpu/o3/commit.hh
@@ -165,6 +165,9 @@ class DefaultCommit
     /** Sets the pointer to the IEW stage. */
     void setIEWStage(IEW *iew_stage);
 
+    /** Skid buffer between rename and commit. */
+    std::queue<DynInstPtr> skidBuffer;
+
     /** The pointer to the IEW stage. Used solely to ensure that
      * various events (traps, interrupts, syscalls) do not occur until
      * all stores have written back.
@@ -256,6 +259,9 @@ class DefaultCommit
     /** Gets instructions from rename and inserts them into the ROB. */
     void getInsts();
 
+    /** Insert all instructions from rename into skidBuffer */
+    void skidInsert();
+
     /** Marks completed instructions using information sent from IEW. */
     void markCompletedInsts();
 
diff --git a/src/cpu/o3/commit_impl.hh b/src/cpu/o3/commit_impl.hh
index 8a8035e73..e51d03994 100644
--- a/src/cpu/o3/commit_impl.hh
+++ b/src/cpu/o3/commit_impl.hh
@@ -26,6 +26,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * Authors: Kevin Lim
+ *          Korey Sewell
  */
 
 #include "config/full_system.hh"
@@ -800,6 +801,10 @@ DefaultCommit<Impl>::commit()
 
         // Try to commit any instructions.
         commitInsts();
+    } else {
+#if THE_ISA != ALPHA_ISA
+        skidInsert();
+#endif
     }
 
     //Check for any activity
@@ -1112,12 +1117,37 @@ DefaultCommit<Impl>::getInsts()
 {
     DPRINTF(Commit, "Getting instructions from Rename stage.\n");
 
+#if THE_ISA == ALPHA_ISA
     // Read any renamed instructions and place them into the ROB.
     int insts_to_process = min((int)renameWidth, fromRename->size);
+#else
+    // Read any renamed instructions and place them into the ROB.
+    int insts_to_process = min((int)renameWidth,
+                               (int)(fromRename->size + skidBuffer.size()));
+    int rename_idx = 0;
 
-    for (int inst_num = 0; inst_num < insts_to_process; ++inst_num)
-    {
-        DynInstPtr inst = fromRename->insts[inst_num];
+    DPRINTF(Commit, "%i insts available to process. Rename Insts:%i "
+            "SkidBuffer Insts:%i\n", insts_to_process, fromRename->size,
+            skidBuffer.size());
+#endif
+
+
+    for (int inst_num = 0; inst_num < insts_to_process; ++inst_num) {
+        DynInstPtr inst;
+
+#if THE_ISA == ALPHA_ISA
+        inst = fromRename->insts[inst_num];
+#else
+        // Get insts from skidBuffer or from Rename
+        if (skidBuffer.size() > 0) {
+            DPRINTF(Commit, "Grabbing skidbuffer inst.\n");
+            inst = skidBuffer.front();
+            skidBuffer.pop();
+        } else {
+            DPRINTF(Commit, "Grabbing rename inst.\n");
+            inst = fromRename->insts[rename_idx++];
+        }
+#endif
         int tid = inst->threadNumber;
 
         if (!inst->isSquashed() &&
@@ -1138,6 +1168,53 @@ DefaultCommit<Impl>::getInsts()
                     inst->readPC(), inst->seqNum, tid);
         }
     }
+
+#if THE_ISA != ALPHA_ISA
+    if (rename_idx < fromRename->size) {
+        DPRINTF(Commit,"Placing Rename Insts into skidBuffer.\n");
+
+        for (;
+             rename_idx < fromRename->size;
+             rename_idx++) {
+            DynInstPtr inst = fromRename->insts[rename_idx];
+            int tid = inst->threadNumber;
+
+            if (!inst->isSquashed()) {
+                DPRINTF(Commit, "Inserting PC %#x [sn:%i] [tid:%i] into ",
+                        "skidBuffer.\n", inst->readPC(), inst->seqNum, tid);
+                skidBuffer.push(inst);
+            } else {
+                DPRINTF(Commit, "Instruction PC %#x [sn:%i] [tid:%i] was "
+                        "squashed, skipping.\n",
+                        inst->readPC(), inst->seqNum, tid);
+            }
+        }
+    }
+#endif
+
+}
+
+template <class Impl>
+void
+DefaultCommit<Impl>::skidInsert()
+{
+    DPRINTF(Commit, "Attempting to any instructions from rename into "
+            "skidBuffer.\n");
+
+    for (int inst_num = 0; inst_num < fromRename->size; ++inst_num) {
+        DynInstPtr inst = fromRename->insts[inst_num];
+        int tid = inst->threadNumber;
+
+        if (!inst->isSquashed()) {
+            DPRINTF(Commit, "Inserting PC %#x [sn:%i] [tid:%i] into ",
+                    "skidBuffer.\n", inst->readPC(), inst->seqNum, tid);
+            skidBuffer.push(inst);
+        } else {
+            DPRINTF(Commit, "Instruction PC %#x [sn:%i] [tid:%i] was "
+                    "squashed, skipping.\n",
+                    inst->readPC(), inst->seqNum, tid);
+        }
+    }
 }
 
 template <class Impl>
diff --git a/src/cpu/o3/fetch_impl.hh b/src/cpu/o3/fetch_impl.hh
index 54e35433b..274c7c46e 100644
--- a/src/cpu/o3/fetch_impl.hh
+++ b/src/cpu/o3/fetch_impl.hh
@@ -1208,9 +1208,8 @@ DefaultFetch<Impl>::fetch(bool &status_change)
     // Now that fetching is completed, update the PC to signify what the next
     // cycle will be.
     if (fault == NoFault) {
-        DPRINTF(Fetch, "[tid:%i]: Setting PC to %08p.\n",tid, next_PC);
-
 #if THE_ISA == ALPHA_ISA
+        DPRINTF(Fetch, "[tid:%i]: Setting PC to %08p.\n",tid, next_PC);
         PC[tid] = next_PC;
         nextPC[tid] = next_PC + instSize;
 #else
@@ -1227,6 +1226,8 @@ DefaultFetch<Impl>::fetch(bool &status_change)
             nextPC[tid] = next_NPC;
             nextNPC[tid] = next_NPC + instSize;
         }
+
+        DPRINTF(Fetch, "[tid:%i]: Setting PC to %08p.\n", tid, PC[tid]);
 #endif
     } else {
         // We shouldn't be in an icache miss and also have a fault (an ITB
@@ -1270,9 +1271,9 @@ DefaultFetch<Impl>::fetch(bool &status_change)
         fetchStatus[tid] = TrapPending;
         status_change = true;
 
-        warn("cycle %lli: fault (%d) detected @ PC %08p", curTick, fault, PC[tid]);
+        warn("cycle %lli: fault (%s) detected @ PC %08p", curTick, fault->name(), PC[tid]);
 #else // !FULL_SYSTEM
-        warn("cycle %lli: fault (%d) detected @ PC %08p", curTick, fault, PC[tid]);
+        warn("cycle %lli: fault (%s) detected @ PC %08p", curTick, fault->name(), PC[tid]);
 #endif // FULL_SYSTEM
     }
 }
diff --git a/src/cpu/o3/mips/cpu_impl.hh b/src/cpu/o3/mips/cpu_impl.hh
index 6b9f3ae10..72b64943b 100644
--- a/src/cpu/o3/mips/cpu_impl.hh
+++ b/src/cpu/o3/mips/cpu_impl.hh
@@ -237,9 +237,7 @@ template <class Impl>
 void
 MipsO3CPU<Impl>::setSyscallReturn(SyscallReturn return_value, int tid)
 {
-    // check for error condition.  Mips syscall convention is to
-    // indicate success/failure in reg a3 (r19) and put the
-    // return value itself in the standard return value reg (v0).
+    // check for error condition.
     if (return_value.successful()) {
         // no error
         this->setArchIntReg(SyscallSuccessReg, 0, tid);