O3CPU: Undo Gabe's changes to remove hwrei and simpalcheck from O3 CPU. Removing hwrei causes

the instruction after the hwrei to be fetched before the ITB/DTB_CM register is updated in a call pal
call sys and thus the translation fails because the user is attempting to access a super page address.

Minimally, it seems as though some sort of fetch stall or refetch after a hwrei is required. I think
this works currently because the hwrei uses the exec context interface, and the o3 stalls when that occurs.

Additionally, these changes don't update the LOCK register and probably break ll/sc. Both o3 changes were
removed since a great deal of manual patching would be required to only remove the hwrei change.

1 files changed, 50 insertions, 0 deletions

diff --git a/src/arch/alpha/ev5.cc b/src/arch/alpha/ev5.cc
index c11b3632e..7dc02a611 100644
--- a/src/arch/alpha/ev5.cc
+++ b/src/arch/alpha/ev5.cc
@@ -547,3 +547,53 @@ copyIprs(ThreadContext *src, ThreadContext *dest)
 }
 
 } // namespace AlphaISA
+
+#if FULL_SYSTEM
+
+using namespace AlphaISA;
+
+Fault
+SimpleThread::hwrei()
+{
+    if (!(readPC() & 0x3))
+        return new UnimplementedOpcodeFault;
+
+    setNextPC(readMiscRegNoEffect(IPR_EXC_ADDR));
+
+    if (!misspeculating()) {
+        if (kernelStats)
+            kernelStats->hwrei();
+    }
+
+    // FIXME: XXX check for interrupts? XXX
+    return NoFault;
+}
+
+/**
+ * Check for special simulator handling of specific PAL calls.
+ * If return value is false, actual PAL call will be suppressed.
+ */
+bool
+SimpleThread::simPalCheck(int palFunc)
+{
+    if (kernelStats)
+        kernelStats->callpal(palFunc, tc);
+
+    switch (palFunc) {
+      case PAL::halt:
+        halt();
+        if (--System::numSystemsRunning == 0)
+            exitSimLoop("all cpus halted");
+        break;
+
+      case PAL::bpt:
+      case PAL::bugchk:
+        if (system->breakpoint())
+            return false;
+        break;
+    }
+
+    return true;
+}
+
+#endif // FULL_SYSTEM