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-rw-r--r--c/src/lib/libbsp/or1k/or1ksim/timer/timer.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/or1k/or1ksim/timer/timer.c b/c/src/lib/libbsp/or1k/or1ksim/timer/timer.c
new file mode 100644
index 0000000000..ec3c33ed0f
--- /dev/null
+++ b/c/src/lib/libbsp/or1k/or1ksim/timer/timer.c
@@ -0,0 +1,64 @@
+/**
+ * @file
+ *
+ * @ingroup or1ksim
+ *
+ * @brief Benchmark timer support.
+ */
+
+/*
+ * Copyright (c) 2014 by Hesham ALMatary
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE
+ */
+
+#include <rtems.h>
+#include <rtems/btimer.h>
+#include <bsp/or1ksim.h>
+#include <rtems/score/or1k-utility.h>
+
+#define OR1KSIM_NANOSECONDS_PER_CLK_CYCLE 10
+
+static bool benchmark_timer_find_average_overhead = false;
+static uint64_t benchmark_timer_base;
+
+void benchmark_timer_initialize(void)
+{
+ benchmark_timer_base = _OR1K_mfspr(CPU_OR1K_SPR_TTCR);
+}
+
+#define AVG_OVERHEAD 0
+#define LEAST_VALID 1
+
+uint32_t benchmark_timer_read( void )
+{
+ uint64_t clicks;
+ uint64_t total;
+ uint64_t delta;
+ /*
+ * Read the timer and see how many clicks (clock cycles)
+ * has passed since timer initialization.
+ */
+ clicks = _OR1K_mfspr(CPU_OR1K_SPR_TTCR);
+
+ delta = clicks - benchmark_timer_base;
+
+ /* total in nanoseconds */
+ total = OR1KSIM_NANOSECONDS_PER_CLK_CYCLE * (delta);
+
+ if ( benchmark_timer_find_average_overhead == true )
+ return total; /* in nanoseconds microsecond units */
+ else {
+ if ( total < LEAST_VALID )
+ return 0; /* below timer resolution */
+
+ return (total - AVG_OVERHEAD);
+ }
+}
+
+void benchmark_timer_disable_subtracting_average_overhead(bool find_flag)
+{
+ benchmark_timer_find_average_overhead = find_flag;
+}