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Diffstat (limited to 'c/src/lib/libbsp/m68k/mvme162/timer/timer.c')
-rw-r--r--c/src/lib/libbsp/m68k/mvme162/timer/timer.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/m68k/mvme162/timer/timer.c b/c/src/lib/libbsp/m68k/mvme162/timer/timer.c
new file mode 100644
index 0000000000..c000fadd28
--- /dev/null
+++ b/c/src/lib/libbsp/m68k/mvme162/timer/timer.c
@@ -0,0 +1,91 @@
+/* Timer_init()
+ *
+ * This routine initializes the Tick Timer 1 on the MVME162 board.
+ *
+ * Input parameters: NONE
+ *
+ * Output parameters: NONE
+ *
+ * NOTE: This routine will not work if the optimizer is enabled
+ * for some compilers. The multiple writes
+ * may be optimized away.
+ *
+ * It is important that the timer start/stop overhead be
+ * determined when porting or modifying this code.
+ *
+ * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
+ * On-Line Applications Research Corporation (OAR).
+ * All rights assigned to U.S. Government, 1994.
+ *
+ * This material may be reproduced by or for the U.S. Government pursuant
+ * to the copyright license under the clause at DFARS 252.227-7013. This
+ * notice must appear in all copies of this file and its derivatives.
+ *
+ * Modifications of respective RTEMS file: COPYRIGHT (c) 1994.
+ * EISCAT Scientific Association. M.Savitski
+ *
+ * This material is a part of the MVME162 Board Support Package
+ * for the RTEMS executive. Its licensing policies are those of the
+ * RTEMS above.
+ *
+ * $Id$
+ */
+
+
+#include <rtems.h>
+#include <bsp.h>
+
+/* Periodic tick interval */
+#define TICK_INTERVAL 0x10000
+#define TIMER_INT_LEVEL 6
+
+int Ttimer_val;
+rtems_boolean Timer_driver_Find_average_overhead;
+
+rtems_isr timerisr();
+
+void Timer_initialize()
+{
+ (void) set_vector( timerisr, (VECTOR_BASE >> 28) * 0x10 + 0x8, 0 );
+
+ Ttimer_val = 0; /* clear timer ISR count */
+ lcsr->vector_base = 0x67800000; /* set vb, enable interrupts */
+ lcsr->to_ctl = 0xE7; /* prescaler to 1 MHz (see Appendix A1) */
+ lcsr->timer_cmp_1 = TICK_INTERVAL;
+ lcsr->timer_cnt_1 = 0; /* clear counter */
+ lcsr->board_ctl |= 7; /* increment, reset-on-compare, clear-ovfl-cnt */
+
+ lcsr->intr_level[0] |= TIMER_INT_LEVEL; /* set int level */
+ lcsr->intr_ena |= 0x01000000; /* enable tick timer 1 interrupt */
+}
+
+#define AVG_OVERHEAD 6 /* It typically takes 3.0 microseconds */
+ /* (6 countdowns) to start/stop the timer. */
+#define LEAST_VALID 10 /* Don't trust a value lower than this */
+
+int Read_timer()
+{
+ unsigned long total;
+
+ total = (Ttimer_val * TICK_INTERVAL) + lcsr->timer_cnt_1;
+
+ if ( Timer_driver_Find_average_overhead == 1 )
+ return total; /* in one-half microsecond units */
+
+ if ( total < LEAST_VALID )
+ return 0; /* below timer resolution */
+
+ return (total-AVG_OVERHEAD); /* in musec units */
+}
+
+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;
+}