bsps: Move benchmark timer to bsps

This patch is a part of the BSP source reorganization.

Update #3285.

bsps/or1k/generic_or1k/btimer/btimer.c

@@ -0,0 +1,64 @@
+/**
+ * @file
+ *
+ * @ingroup generic_or1k
+ *
+ * @brief Benchmark timer support.
+ */
+
+/*
+ * Copyright (c) 2014-2015 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/generic_or1k.h>
+#include <rtems/score/or1k-utility.h>
+
+#define OR1K_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
+
+benchmark_timer_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 = OR1K_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;
+}