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Diffstat (limited to 'c/src/lib/libbsp/sparc/leon3/timer/timer.c')
-rw-r--r--c/src/lib/libbsp/sparc/leon3/timer/timer.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/sparc/leon3/timer/timer.c b/c/src/lib/libbsp/sparc/leon3/timer/timer.c
new file mode 100644
index 0000000000..805616e475
--- /dev/null
+++ b/c/src/lib/libbsp/sparc/leon3/timer/timer.c
@@ -0,0 +1,82 @@
+/* timer.c
+ *
+ * This file implements a benchmark timer using timer 2.
+ *
+ * COPYRIGHT (c) 1989-1998.
+ * On-Line Applications Research Corporation (OAR).
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.com/license/LICENSE.
+ *
+ * Ported to LEON implementation of the SPARC by On-Line Applications
+ * Research Corporation (OAR) under contract to the European Space
+ * Agency (ESA).
+ *
+ * LEON modifications of respective RTEMS file: COPYRIGHT (c) 1995.
+ * European Space Agency.
+ *
+ * $Id$
+ */
+
+
+#include <bsp.h>
+
+rtems_boolean Timer_driver_Find_average_overhead;
+
+rtems_boolean Timer_driver_Is_initialized = FALSE;
+
+extern volatile LEON3_Timer_Regs_Map *LEON3_Timer_Regs;
+
+void Timer_initialize()
+{
+ /*
+ * Timer runs long and accurate enough not to require an interrupt.
+ */
+ if (LEON3_Timer_Regs) {
+ if ( Timer_driver_Is_initialized == FALSE ) {
+ /* approximately 1 us per countdown */
+ LEON3_Timer_Regs->reload_t1 = 0xffffff;
+ LEON3_Timer_Regs->value_t1 = 0xffffff;
+ } else {
+ Timer_driver_Is_initialized = TRUE;
+ }
+ LEON3_Timer_Regs->conf_t1 = LEON3_GPTIMER_EN | LEON3_GPTIMER_LD;
+ }
+}
+
+#define AVG_OVERHEAD 3 /* It typically takes 3.0 microseconds */
+ /* to start/stop the timer. */
+#define LEAST_VALID 2 /* Don't trust a value lower than this */
+
+int Read_timer()
+{
+ rtems_unsigned32 total;
+
+ if (LEON3_Timer_Regs) {
+ total = LEON3_Timer_Regs->value_t1;
+
+ total = 0xffffff - total;
+
+ if ( Timer_driver_Find_average_overhead == 1 )
+ return total; /* in one microsecond units */
+
+ if ( total < LEAST_VALID )
+ return 0; /* below timer resolution */
+
+ return total - AVG_OVERHEAD;
+ }
+ return 0;
+}
+
+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;
+}