diff -rC2 simplesim-arm-1/sim-outorder.c simplesim-arm-2/sim-outorder.c
*** simplesim-arm-1/sim-outorder.c	2005-03-14 13:37:32.000000000 +0000
--- simplesim-arm-2/sim-outorder.c	2005-03-16 17:46:07.000000000 +0000
***************
*** 510,519 ****
  /* cycle counter */
  tick_t sim_cycle = 0;
  tick_t timer_next_interrupt_at = 0;
  tick_t timer_period = 0;
  int timer_return_from_interrupt_address = 0;
  int timer_do_return_from_interrupt = 0;
! enum { PENDING_FLUSH , 
!     HANDLING , NORMAL } timer_int_state ;
  
  static void do_return_from_interrupt ( bool_t swap_regs ) ;
--- 510,520 ----
  /* cycle counter */
  tick_t sim_cycle = 0;
+ tick_t sim_cycles_in_idle_task = 0;
  tick_t timer_next_interrupt_at = 0;
  tick_t timer_period = 0;
  int timer_return_from_interrupt_address = 0;
+ int sim_in_idle_task = 0;
  int timer_do_return_from_interrupt = 0;
! enum { PENDING_FLUSH , HANDLING , NORMAL } timer_int_state ;
  
  static void do_return_from_interrupt ( bool_t swap_regs ) ;
***************
*** 1501,1504 ****
--- 1502,1508 ----
  		   "total simulation time in cycles",
  		   &sim_cycle, /* initial value */0, /* format */NULL);
+   stat_reg_counter(sdb, "sim_cycles_in_idle_task",
+ 		   "total simulation time spent in idle task",
+ 		   &sim_cycles_in_idle_task, /* initial value */0, /* format */NULL);
    stat_reg_formula(sdb, "sim_IPC",
  		   "instructions per cycle",
***************
*** 5376,5379 ****
--- 5380,5384 ----
          allow_dispatch = ( timer_int_state != PENDING_FLUSH )
                      || in_flow ;
+         sim_in_idle_task = 0 ;
  
        /* RUU/LSQ sanity checks */
***************
*** 5556,5559 ****
--- 5561,5583 ----
      {
          case NORMAL :
+                 if ( sim_in_idle_task )
+                 {
+                     tick_t cycle_warp ;
+ 
+                     /* Stay in idle task until we get a timer interrupt.
+                      * Of course, we might never get one... Check for that */
+                     if (( timer_next_interrupt_at <= 0 ) /* timer off */
+                     || (( PSR & 0x80 ) != 0 )) /* ints disabled */
+                     {
+                         panic ( "entered idle task without enabling "
+                             "interrupts and/or timer" ) ;
+                     }
+                     cycle_warp = timer_next_interrupt_at - sim_cycle ;
+                     if ( cycle_warp > 0 )
+                     {
+                         sim_cycles_in_idle_task += cycle_warp ;
+                         sim_cycle += cycle_warp ;
+                     }
+                 }
                  if (( timer_next_interrupt_at > 0 )
                  && (( PSR & 0x80 ) == 0 ) 
***************
*** 5561,5573 ****
                  && ( sim_cycle >= timer_next_interrupt_at ))
                  {
                      double seconds = (( (double) ((long long) sim_cycle )) /
                          ( (double) MD_CLOCK_CYCLES_PER_MICROSECOND *
                              1000000.0 )) ;
                      timer_int_state = PENDING_FLUSH ;
                      timer_do_return_from_interrupt = 0 ;
                      timer_next_interrupt_at = sim_cycle + timer_period ;
-                     fprintf ( stderr , "tick - %lld - %1.4f seconds\n" , 
-                             ((long long) sim_cycle ) , seconds ) ;
- 		    /* verbose = 1 ; */
                  }
                  break ;
--- 5585,5599 ----
                  && ( sim_cycle >= timer_next_interrupt_at ))
                  {
+ #ifdef JACK_DEBUGGING
                      double seconds = (( (double) ((long long) sim_cycle )) /
                          ( (double) MD_CLOCK_CYCLES_PER_MICROSECOND *
                              1000000.0 )) ;
+ 
+                     fprintf ( stderr , "tick - %lld - %1.4f seconds\n" , 
+                             ((long long) sim_cycle ) , seconds ) ;
+ #endif
                      timer_int_state = PENDING_FLUSH ;
                      timer_do_return_from_interrupt = 0 ;
                      timer_next_interrupt_at = sim_cycle + timer_period ;
                  }
                  break ;
diff -rC2 simplesim-arm-1/syscall.c simplesim-arm-2/syscall.c
*** simplesim-arm-1/syscall.c	2005-03-14 13:37:32.000000000 +0000
--- simplesim-arm-2/syscall.c	2005-03-16 17:39:06.000000000 +0000
***************
*** 1010,1013 ****
--- 1010,1014 ----
  extern tick_t timer_period ;
  extern tick_t sim_cycle ;
+ extern int sim_in_idle_task ;
  
  /* ARM SYSTEM CALL CONVENTIONS
***************
*** 2096,2099 ****
--- 2097,2102 ----
                          timer_next_interrupt_at = sim_cycle + timer_period ;
                          break ;
+         case 0x99991 :  sim_in_idle_task = 1 ;
+                         break ;