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-rw-r--r--bsps/powerpc/shared/btimer/btimer-ppc-dec.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/bsps/powerpc/shared/btimer/btimer-ppc-dec.c b/bsps/powerpc/shared/btimer/btimer-ppc-dec.c
new file mode 100644
index 0000000000..d161710732
--- /dev/null
+++ b/bsps/powerpc/shared/btimer/btimer-ppc-dec.c
@@ -0,0 +1,88 @@
+/**
+ * @file
+ * @brief
+ *
+ * This file implements a benchmark timer using the PPC Timebase Register.
+ */
+
+/*
+ * COPYRIGHT (c) 1989-2014.
+ * On-Line Applications Research Corporation (OAR).
+ *
+ * The license and distribution terms for this file may in
+ * the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#include <bsp.h>
+#include <rtems.h>
+#include <rtems/system.h>
+#include <rtems/btimer.h>
+#include <assert.h>
+#include <libcpu/powerpc-utility.h>
+
+#ifndef BSP_Convert_decrementer
+#define BSP_Convert_decrementer(value) (value)
+#endif
+
+uint64_t Timer_driver_Start_time;
+
+bool benchmark_timer_find_average_overhead = false;
+unsigned clicks_overhead = 0;
+
+/*
+ * Timer Get overhead
+ */
+static int Timer_get_clicks_overhead(void)
+{
+ uint64_t clicks;
+
+ PPC_Set_timebase_register((uint64_t) 0);
+ clicks = PPC_Get_timebase_register();
+ assert(clicks <= 0xffffffff);
+ clicks_overhead = (unsigned) clicks;
+ return clicks_overhead;
+}
+
+/*
+ * benchmark_timer_initialize
+ */
+void benchmark_timer_initialize(void)
+{
+
+ /*
+ * Timer runs long and accurate enough not to require an interrupt.
+ */
+
+ if (clicks_overhead == 0) clicks_overhead = Timer_get_clicks_overhead();
+ PPC_Set_timebase_register((uint64_t) 0);
+}
+
+
+/*
+ * benchmark_timer_read
+ */
+
+benchmark_timer_t benchmark_timer_read(void)
+{
+ uint64_t total64;
+ uint32_t total;
+
+ /* approximately CLOCK_SPEED clicks per microsecond */
+
+ total64 = PPC_Get_timebase_register();
+
+ assert( total64 <= 0xffffffff ); /* fits into a uint32_t */
+
+ total = (uint32_t) total64;
+
+ if ( benchmark_timer_find_average_overhead == true )
+ return total; /* in "clicks" of the decrementer units */
+
+ return (int) BSP_Convert_decrementer(total - clicks_overhead);
+}
+
+void benchmark_timer_disable_subtracting_average_overhead(bool find_flag)
+{
+ benchmark_timer_find_average_overhead = find_flag;
+}