1 files changed, 91 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/powerpc/mvme2307/timer/timer.c b/c/src/lib/libbsp/powerpc/mvme2307/timer/timer.c
new file mode 100644
index 0000000000..60a1a78248
--- /dev/null
+++ b/c/src/lib/libbsp/powerpc/mvme2307/timer/timer.c
@@ -0,0 +1,91 @@
+/*  timer.c
+ *
+ *  This file manages the benchmark timer used by the RTEMS Timing Test
+ *  Suite.  Each measured time period is demarcated by calls to
+ *  Timer_initialize() and Read_timer().  Read_timer() usually returns
+ *  the number of microseconds since Timer_initialize() exitted.
+ *
+ *  This version returns the number of nanoseconds since Timer_initialize() 
+ *  exited, since the '604 is very fast at 300MHz.  Actual resolution is
+ *  60 nsec.
+ *
+ *  NOTE: It is important that the timer start/stop overhead be
+ *        determined when porting or modifying this code.
+ *
+ *  COPYRIGHT (c) 1989-1998.
+ *  On-Line Applications Research Corporation (OAR).
+ *  Copyright assigned to U.S. Government, 1994.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.OARcorp.com/rtems/license.html.
+ *
+ *  $Id$
+ */
+
+#include <rtems.h>
+#include <bsp.h>
+
+rtems_unsigned32 Timer_start;
+rtems_boolean Timer_driver_Find_average_overhead;
+
+void Timer_initialize( void )
+{
+    rtems_unsigned32 clicks;
+
+    asm volatile ("mfspr %0,268" : "=r" (clicks) :);
+    Timer_start = clicks;
+}
+
+/*
+ *  The following controls the behavior of Read_timer().
+ *
+ *  AVG_OVEREHAD is the overhead for starting and stopping the timer.  It
+ *  is usually deducted from the number returned.
+ *
+ *  LEAST_VALID is the lowest number this routine should trust.  Numbers
+ *  below this are "noise" and zero is returned.
+ */
+
+#define AVG_OVERHEAD      7  /* On average, it takes 7.4 nanoseconds */
+                             /* (Y countdowns) to start/stop the timer. */
+
+#define NSEC_PER_TICK    60  
+
+int Read_timer( void )
+{
+    rtems_unsigned32 clicks;
+    rtems_unsigned32 total;
+
+    /*
+     *  Read the timer and see how many clicks it has been since we started.
+     *  Timer overflows every 257 seconds, so multiple overflows are deemed
+     *  impossible.
+     */
+
+    asm volatile ("mfspr %0,268" : "=r" (clicks) :);
+    total = (clicks - Timer_start);
+
+    if ( Timer_driver_Find_average_overhead == 1 ) {
+        return total * NSEC_PER_TICK;          /* in nanoseconds */
+    } else {
+        /*
+        *   convert total into nanoseconds
+        */
+        return total * NSEC_PER_TICK - AVG_OVERHEAD;
+    }
+}
+
+/*
+ *  Empty function call used in loops to measure basic cost of looping
+ *  in Timing Test Suite.
+ */
+
+rtems_status_code Empty_function( void ) {
+    return RTEMS_SUCCESSFUL;
+}
+
+void Set_find_average_overhead(rtems_boolean find_flag) {
+    Timer_driver_Find_average_overhead = find_flag;
+}
+