ARM: Don't return the result of a table walk the same cycle it's completed.

The L1 cache may have been accessed to provide this data, which confuses
it, if it ends up being accesses twice in one cycle. Instead wait 1 tick
which will force the timing simple CPU to forward to its next clock cycle
when the translation completes.

Also prevent multiple outstanding table walks from occuring at once.

1 files changed, 12 insertions, 0 deletions

diff --git a/src/arch/arm/table_walker.hh b/src/arch/arm/table_walker.hh
index dc801dde8..fde553ff4 100644
--- a/src/arch/arm/table_walker.hh
+++ b/src/arch/arm/table_walker.hh
@@ -320,6 +320,11 @@ class TableWalker : public MemObject
      * require an additional level. */
     std::list<WalkerState *> stateQueueL2;
 
+    /** Queue of requests that have passed are waiting because the walker is
+     * currently busy. */
+    std::list<WalkerState *> pendingQueue;;
+
+
     /** Port to issue translation requests from */
     DmaPort *port;
 
@@ -331,6 +336,9 @@ class TableWalker : public MemObject
 
     WalkerState *currState;
 
+    /** If a timing translation is currently in progress */
+    bool pending;
+
   public:
     typedef ArmTableWalkerParams Params;
     TableWalker(const Params *p);
@@ -362,7 +370,11 @@ class TableWalker : public MemObject
     void doL2DescriptorWrapper();
     EventWrapper<TableWalker, &TableWalker::doL2DescriptorWrapper> doL2DescEvent;
 
+    Fault processWalk();
+    void processWalkWrapper();
+    EventWrapper<TableWalker, &TableWalker::processWalkWrapper> doProcessEvent;
 
+    void nextWalk(ThreadContext *tc);
 };