2 files changed, 47 insertions, 12 deletions

diff --git a/src/dev/arm/generic_timer.cc b/src/dev/arm/generic_timer.cc
index 48f70e135..6332b8f4d 100644
--- a/src/dev/arm/generic_timer.cc
+++ b/src/dev/arm/generic_timer.cc
@@ -109,8 +109,12 @@ ArchTimer::counterLimitReached()
 
     DPRINTF(Timer, "Counter limit reached\n");
     if (!_control.imask) {
-        DPRINTF(Timer, "Causing interrupt\n");
-        _interrupt.send();
+        if (scheduleEvents()) {
+            DPRINTF(Timer, "Causing interrupt\n");
+            _interrupt.send();
+        } else {
+            DPRINTF(Timer, "Kvm mode; skipping simulated interrupt\n");
+        }
     }
 }
 
@@ -122,10 +126,12 @@ ArchTimer::updateCounter()
     if (value() >= _counterLimit) {
         counterLimitReached();
     } else {
-        const auto period(_systemCounter.period());
         _control.istatus = 0;
-        _parent.schedule(_counterLimitReachedEvent,
-             curTick() + (_counterLimit - value()) * period);
+        if (scheduleEvents()) {
+            const auto period(_systemCounter.period());
+            _parent.schedule(_counterLimitReachedEvent,
+                 curTick() + (_counterLimit - value()) * period);
+        }
     }
 }
 
@@ -234,12 +240,13 @@ ArchTimer::Interrupt::clear()
 
 GenericTimer::GenericTimer(GenericTimerParams *p)
     : SimObject(p),
+      system(*p->system),
       gic(p->gic),
       irqPhys(p->int_phys),
       irqVirt(p->int_virt)
 {
     fatal_if(!p->system, "No system specified, can't instantiate timer.\n");
-    p->system->setGenericTimer(this);
+    system.setGenericTimer(this);
 }
 
 void
@@ -303,7 +310,7 @@ GenericTimer::createTimers(unsigned cpus)
     timers.resize(cpus);
     for (unsigned i = old_cpu_count; i < cpus; ++i) {
         timers[i].reset(
-            new CoreTimers(*this, i, irqPhys, irqVirt));
+            new CoreTimers(*this, system, i, irqPhys, irqVirt));
     }
 }
 
diff --git a/src/dev/arm/generic_timer.hh b/src/dev/arm/generic_timer.hh
index 3eec1d42e..ccfb1277f 100644
--- a/src/dev/arm/generic_timer.hh
+++ b/src/dev/arm/generic_timer.hh
@@ -42,6 +42,7 @@
 #define __DEV_ARM_GENERIC_TIMER_HH__
 
 #include "arch/arm/isa_device.hh"
+#include "arch/arm/system.hh"
 #include "base/bitunion.hh"
 #include "dev/arm/base_gic.hh"
 #include "sim/core.hh"
@@ -159,6 +160,8 @@ class ArchTimer : public Serializable, public Drainable
     void counterLimitReached();
     EventFunctionWrapper _counterLimitReachedEvent;
 
+    virtual bool scheduleEvents() { return true; }
+
   public:
     ArchTimer(const std::string &name,
               SimObject &parent,
@@ -201,6 +204,28 @@ class ArchTimer : public Serializable, public Drainable
     ArchTimer(const ArchTimer &t);
 };
 
+class ArchTimerKvm : public ArchTimer
+{
+  private:
+    ArmSystem &system;
+
+  public:
+    ArchTimerKvm(const std::string &name,
+                 ArmSystem &system,
+                 SimObject &parent,
+                 SystemCounter &sysctr,
+                 const Interrupt &interrupt)
+      : ArchTimer(name, parent, sysctr, interrupt), system(system) {}
+
+  protected:
+    // For ArchTimer's in a GenericTimerISA with Kvm execution about
+    // to begin, skip rescheduling the event.
+    // Otherwise, we should reschedule the event (if necessary).
+    bool scheduleEvents() override {
+        return !system.validKvmEnvironment();
+    }
+};
+
 class GenericTimer : public SimObject
 {
   public:
@@ -215,25 +240,25 @@ class GenericTimer : public SimObject
 
   protected:
     struct CoreTimers {
-        CoreTimers(GenericTimer &parent, unsigned cpu,
+        CoreTimers(GenericTimer &parent, ArmSystem &system, unsigned cpu,
                    unsigned _irqPhys, unsigned _irqVirt)
             : irqPhys(*parent.gic, _irqPhys, cpu),
               irqVirt(*parent.gic, _irqVirt, cpu),
               // This should really be phys_timerN, but we are stuck with
               // arch_timer for backwards compatibility.
               phys(csprintf("%s.arch_timer%d", parent.name(), cpu),
-                   parent, parent.systemCounter,
+                   system, parent, parent.systemCounter,
                    irqPhys),
               virt(csprintf("%s.virt_timer%d", parent.name(), cpu),
-                   parent, parent.systemCounter,
+                   system, parent, parent.systemCounter,
                    irqVirt)
         {}
 
         ArchTimer::Interrupt irqPhys;
         ArchTimer::Interrupt irqVirt;
 
-        ArchTimer phys;
-        ArchTimer virt;
+        ArchTimerKvm phys;
+        ArchTimerKvm virt;
 
       private:
         // Disable copying
@@ -250,6 +275,9 @@ class GenericTimer : public SimObject
     std::vector<std::unique_ptr<CoreTimers>> timers;
 
   protected: // Configuration
+    /// ARM system containing this timer
+    ArmSystem &system;
+
     /// Pointer to the GIC, needed to trigger timer interrupts.
     BaseGic *const gic;