diff --git a/arch/alpha/isa_desc b/arch/alpha/isa_desc
index 75f765029..09fb4a50a 100644
--- a/arch/alpha/isa_desc
+++ b/arch/alpha/isa_desc
@@ -2425,9 +2425,21 @@ decode OPCODE default Unknown::unknown() {
 		if (!xc->misspeculating())
 		    Annotate::EndInterval(xc);
 	    }}, No_OpClass);
-	    0x20: m5exit({{
+	    0x20: m5exit_old({{
 		if (!xc->misspeculating())
-		    SimExit("m5_exit instruction encountered");
+		    SimExit(curTick, "m5_exit_old instruction encountered");
+	    }}, No_OpClass);
+	    0x21: m5exit({{
+		if (!xc->misspeculating()) {
+		    Tick when = curTick;
+		    Tick delay = xc->regs.intRegFile[16];
+		    if (delay != 0) {
+			delay *= ticksPerUS;
+			delay /= 1000;
+			when += delay;
+		    }
+		    SimExit(when, "m5_exit instruction encountered");
+		}
 	    }}, No_OpClass);
             0x30: initparam({{ Ra = xc->cpu->system->init_param; }});
             0x40: resetstats({{
diff --git a/sim/sim_events.cc b/sim/sim_events.cc
index 5f24de516..165bab2bf 100644
--- a/sim/sim_events.cc
+++ b/sim/sim_events.cc
@@ -64,9 +64,9 @@ SimExitEvent::description()
 }
 
 void
-SimExit(const char *message)
+SimExit(Tick when, const char *message)
 {
-    static SimExitEvent event(message);
+    static SimExitEvent event(when, message);
 }
 
 //
diff --git a/sim/sim_events.hh b/sim/sim_events.hh
index 0029a8404..bca978ce1 100644
--- a/sim/sim_events.hh
+++ b/sim/sim_events.hh
@@ -66,7 +66,7 @@ class SimExitEvent : public Event
     virtual const char *description();
 };
 
-void SimExit(const char *message);
+void SimExit(Tick when, const char *message);
 
 //
 // Event class to terminate simulation after 'n' related events have
diff --git a/sim/universe.cc b/sim/universe.cc
index 8274d84ca..4cfcdc563 100644
--- a/sim/universe.cc
+++ b/sim/universe.cc
@@ -38,6 +38,9 @@ using namespace std;
 
 Tick curTick = 0;
 Tick ticksPerSecond;
+Tick ticksPerMS;
+Tick ticksPerUS;
+Tick ticksPerNS;
 
 class UniverseParamContext : public ParamContext
 {
@@ -49,10 +52,13 @@ class UniverseParamContext : public ParamContext
 UniverseParamContext universe("Universe");
 
 Param<Tick> universe_freq(&universe, "frequency", "tick frequency",
-                            200000000);
+                          200000000);
 
 void
 UniverseParamContext::checkParams()
 {
     ticksPerSecond = universe_freq;
+    ticksPerMS = universe_freq / 1000;
+    ticksPerUS = universe_freq / (1000 * 1000);
+    ticksPerNS = universe_freq / (1000 * 1000 * 1000);
 }