CPU: Moving towards a more general port across CPU models

This patch performs minimal changes to move the instruction and data
ports from specialised subclasses to the base CPU (to the largest
degree possible). Ultimately it servers to make the CPU(s) have a
well-defined interface to the memory sub-system.

1 files changed, 10 insertions, 77 deletions

diff --git a/src/cpu/o3/fetch_impl.hh b/src/cpu/o3/fetch_impl.hh
index ccab47d2f..d145fb099 100644
--- a/src/cpu/o3/fetch_impl.hh
+++ b/src/cpu/o3/fetch_impl.hh
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010 ARM Limited
+ * Copyright (c) 2010-2011 ARM Limited
  * All rights reserved.
  *
  * The license below extends only to copyright in the software and shall
@@ -71,68 +71,6 @@
 using namespace std;
 
 template<class Impl>
-void
-DefaultFetch<Impl>::IcachePort::setPeer(Port *port)
-{
-    Port::setPeer(port);
-
-    fetch->setIcache();
-}
-
-template<class Impl>
-Tick
-DefaultFetch<Impl>::IcachePort::recvAtomic(PacketPtr pkt)
-{
-    panic("DefaultFetch doesn't expect recvAtomic callback!");
-    return curTick();
-}
-
-template<class Impl>
-void
-DefaultFetch<Impl>::IcachePort::recvFunctional(PacketPtr pkt)
-{
-    DPRINTF(Fetch, "DefaultFetch doesn't update its state from a "
-            "functional call.\n");
-}
-
-template<class Impl>
-void
-DefaultFetch<Impl>::IcachePort::recvStatusChange(Status status)
-{
-    if (status == RangeChange) {
-        if (!snoopRangeSent) {
-            snoopRangeSent = true;
-            sendStatusChange(Port::RangeChange);
-        }
-        return;
-    }
-
-    panic("DefaultFetch doesn't expect recvStatusChange callback!");
-}
-
-template<class Impl>
-bool
-DefaultFetch<Impl>::IcachePort::recvTiming(PacketPtr pkt)
-{
-    DPRINTF(Fetch, "Received timing\n");
-    if (pkt->isResponse()) {
-        // We shouldn't ever get a block in ownership state
-        assert(!(pkt->memInhibitAsserted() && !pkt->sharedAsserted()));
-
-        fetch->processCacheCompletion(pkt);
-    }
-    //else Snooped a coherence request, just return
-    return true;
-}
-
-template<class Impl>
-void
-DefaultFetch<Impl>::IcachePort::recvRetry()
-{
-    fetch->recvRetry();
-}
-
-template<class Impl>
 DefaultFetch<Impl>::DefaultFetch(O3CPU *_cpu, DerivO3CPUParams *params)
     : cpu(_cpu),
       branchPred(params),
@@ -191,17 +129,6 @@ DefaultFetch<Impl>::DefaultFetch(O3CPU *_cpu, DerivO3CPUParams *params)
 
     // Get the size of an instruction.
     instSize = sizeof(TheISA::MachInst);
-
-    // Name is finally available, so create the port.
-    icachePort = new IcachePort(this);
-
-    icachePort->snoopRangeSent = false;
-
-#if USE_CHECKER
-    if (cpu->checker) {
-        cpu->checker->setIcachePort(icachePort);
-    }
-#endif
 }
 
 template <class Impl>
@@ -404,8 +331,10 @@ template<class Impl>
 void
 DefaultFetch<Impl>::setIcache()
 {
+    assert(cpu->getIcachePort()->isConnected());
+
     // Size of cache block.
-    cacheBlkSize = icachePort->peerBlockSize();
+    cacheBlkSize = cpu->getIcachePort()->peerBlockSize();
 
     // Create mask to get rid of offset bits.
     cacheBlkMask = (cacheBlkSize - 1);
@@ -496,6 +425,10 @@ template <class Impl>
 void
 DefaultFetch<Impl>::takeOverFrom()
 {
+    // the instruction port is now connected so we can get the block
+    // size
+    setIcache();
+
     // Reset all state
     for (ThreadID i = 0; i < Impl::MaxThreads; ++i) {
         stalls[i].decode = 0;
@@ -686,7 +619,7 @@ DefaultFetch<Impl>::finishTranslation(Fault fault, RequestPtr mem_req)
         fetchedCacheLines++;
 
         // Access the cache.
-        if (!icachePort->sendTiming(data_pkt)) {
+        if (!cpu->getIcachePort()->sendTiming(data_pkt)) {
             assert(retryPkt == NULL);
             assert(retryTid == InvalidThreadID);
             DPRINTF(Fetch, "[tid:%i] Out of MSHRs!\n", tid);
@@ -1405,7 +1338,7 @@ DefaultFetch<Impl>::recvRetry()
         assert(retryTid != InvalidThreadID);
         assert(fetchStatus[retryTid] == IcacheWaitRetry);
 
-        if (icachePort->sendTiming(retryPkt)) {
+        if (cpu->getIcachePort()->sendTiming(retryPkt)) {
             fetchStatus[retryTid] = IcacheWaitResponse;
             retryPkt = NULL;
             retryTid = InvalidThreadID;