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authorJoel Sherrill <joel.sherrill@OARcorp.com>2000-02-22 18:39:52 +0000
committerJoel Sherrill <joel.sherrill@OARcorp.com>2000-02-22 18:39:52 +0000
commit61ba976360804d85f9203821518bb4b132852188 (patch)
tree28e72dd94472e21da42f5f5d1e82912a9f83852a /c/src/lib/libbsp/c4x/c4xsim/timer
parent9f9efbca8df3a024607572eb7413d2cacddb73d2 (diff)
downloadrtems-61ba976360804d85f9203821518bb4b132852188.tar.bz2
New port of RTEMS to TI C3x and C4x.
Diffstat (limited to 'c/src/lib/libbsp/c4x/c4xsim/timer')
-rw-r--r--c/src/lib/libbsp/c4x/c4xsim/timer/Makefile.am32
-rw-r--r--c/src/lib/libbsp/c4x/c4xsim/timer/timer.c117
2 files changed, 149 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/c4x/c4xsim/timer/Makefile.am b/c/src/lib/libbsp/c4x/c4xsim/timer/Makefile.am
new file mode 100644
index 0000000000..7f16dcc233
--- /dev/null
+++ b/c/src/lib/libbsp/c4x/c4xsim/timer/Makefile.am
@@ -0,0 +1,32 @@
+##
+## $Id$
+##
+
+AUTOMAKE_OPTIONS = foreign 1.4
+
+PGM = $(ARCH)/timer.rel
+
+C_FILES = timer.c
+C_O_FILES = $(C_FILES:%.c=$(ARCH)/%.o)
+
+OBJS = $(C_O_FILES)
+
+include $(RTEMS_ROOT)/make/custom/@RTEMS_BSP@.cfg
+include $(top_srcdir)/../../../../../../automake/lib.am
+
+#
+# (OPTIONAL) Add local stuff here using +=
+#
+
+$(PGM): $(OBJS)
+ $(make-rel)
+
+# the .rel file built here will be put into libbsp.a by ../wrapup/Makefile
+
+all-local: $(ARCH) $(OBJS) $(PGM)
+
+.PRECIOUS: $(PGM)
+
+EXTRA_DIST = timer.c
+
+include $(top_srcdir)/../../../../../../automake/local.am
diff --git a/c/src/lib/libbsp/c4x/c4xsim/timer/timer.c b/c/src/lib/libbsp/c4x/c4xsim/timer/timer.c
new file mode 100644
index 0000000000..b32166c330
--- /dev/null
+++ b/c/src/lib/libbsp/c4x/c4xsim/timer/timer.c
@@ -0,0 +1,117 @@
+/* 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.
+ *
+ * NOTE: It is important that the timer start/stop overhead be
+ * determined when porting or modifying this code.
+ *
+ * COPYRIGHT (c) 1989-1999.
+ * 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.OARcorp.com/rtems/license.html.
+ *
+ * $Id$
+ */
+
+#include <rtems.h>
+#include <bsp.h>
+#include <c4xio.h>
+
+rtems_unsigned32 Timer_interrupts;
+rtems_boolean Timer_driver_Find_average_overhead;
+
+static unsigned32 start;
+
+void Timer_initialize( void )
+{
+
+ /*
+ * Timer has never overflowed. This may not be necessary on some
+ * implemenations of timer but ....
+ */
+
+
+ c4x_timer_stop(C4X_TIMER_0);
+ c4x_timer_set_period(C4X_TIMER_0, 0xffffffff); /* so no interupts */
+ c4x_timer_start(C4X_TIMER_0);
+ start = c4x_timer_get_counter(C4X_TIMER_0);
+
+ Timer_interrupts = 0;
+
+ /*
+ * Somehow start the timer
+ */
+}
+
+/*
+ * 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 0 /* It typically takes X.X microseconds */
+ /* (Y countdowns) to start/stop the timer. */
+ /* This value is in microseconds. */
+#define LEAST_VALID 1 /* Don't trust a clicks value lower than this */
+
+int Read_timer( void )
+{
+ rtems_unsigned32 clicks;
+ rtems_unsigned32 total;
+ int tmp;
+
+ /*
+ * Read the timer and see how many clicks it has been since we started.
+ */
+
+ clicks = c4x_timer_get_counter(C4X_TIMER_0);
+ clicks -= start;
+
+ /*
+ * Total is calculated by taking into account the number of timer overflow
+ * interrupts since the timer was initialized and clicks since the last
+ * interrupts.
+ */
+
+ total = clicks * 1;
+
+ if ( Timer_driver_Find_average_overhead == 1 ) {
+ return total; /* in count units where each count is */
+ /* 1 / (clock frequency/2) */
+ } else {
+ if ( total < LEAST_VALID )
+ return 0; /* below timer resolution */
+ /*
+ * Somehow convert total into microseconds
+ */
+ tmp = (int) ((float) total * ((1.0 / 25.0)));
+ return (tmp - 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;
+}
+