bsps: Move benchmark timer to bsps

This patch is a part of the BSP source reorganization.

Update #3285.

1 files changed, 137 insertions, 0 deletions

diff --git a/bsps/nios2/nios2_iss/btimer/btimer.c b/bsps/nios2/nios2_iss/btimer/btimer.c
new file mode 100644
index 0000000000..fbb20d892b
--- /dev/null
+++ b/bsps/nios2/nios2_iss/btimer/btimer.c
@@ -0,0 +1,137 @@
+/*
+ * This file manages the benchmark timer used by the RTEMS Timing Test
+ * Suite.  Each measured time period is demarcated by calls to
+ * benchmark_timer_initialize() and benchmark_timer_read(). 
+ * benchmark_timer_read() usually returns the number of microseconds
+ * since benchmark_timer_initialize() exitted.
+ *
+ *  NOTE: It is important that the timer start/stop overhead be
+ *        determined when porting or modifying this code.
+ */
+
+/*
+ *  COPYRIGHT (c) 2005-2006 Kolja Waschk rtemsdev/ixo.de
+ *  Derived from no_cpu/no_bsp/timer/timer.c 1.9,
+ *  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.rtems.org/license/LICENSE.
+ */
+
+#define TIMER_WRAPS_AFTER_1MS 0
+
+#include <rtems.h>
+#include <rtems/btimer.h>
+#include <rtems/score/cpu.h>
+#include <bsp.h>
+
+volatile uint32_t Timer_interrupts;
+bool benchmark_timer_find_average_overhead;
+
+#define TIMER_REGS ((altera_avalon_timer_regs*)NIOS2_IO_BASE(TIMER_BASE))
+
+static rtems_isr timerisr(rtems_vector_number vector)
+{
+  TIMER_REGS->status = 0;
+  Timer_interrupts++;
+}
+
+void benchmark_timer_initialize( void )
+{
+  /* Disable timer interrupt, stop timer */
+
+  TIMER_REGS->control = ALTERA_AVALON_TIMER_CONTROL_STOP_MSK;
+
+  set_vector(timerisr, TIMER_VECTOR, 1);
+
+  /* Enable interrupt processing */
+
+  NIOS2_IENABLE(1 << TIMER_VECTOR);
+
+#if TIMER_WRAPS_AFTER_1MS
+  /* Writing to periodl/h resets the counter and eventually
+     stops it. If the timer hasn't been configured with fixed
+     period, set it to 1 ms now */
+
+  TIMER_REGS->period_hi = (TIMER_FREQ/1000)>>16;
+  TIMER_REGS->period_lo = (TIMER_FREQ/1000)&0xFFFF;
+#else
+  /* Writing to periodl/h resets the counter and eventually
+     stops it. Set max period */
+
+  TIMER_REGS->period_hi = 0xFFFF;
+  TIMER_REGS->period_lo = 0xFFFF;
+#endif
+
+  /* For timers that can be stopped, writing to periodl/h
+     also stopped the timer and we have to manually start it. */
+
+  TIMER_REGS->control = ALTERA_AVALON_TIMER_CONTROL_ITO_MSK |
+                        ALTERA_AVALON_TIMER_CONTROL_CONT_MSK |
+                        ALTERA_AVALON_TIMER_CONTROL_START_MSK;
+
+  /* This is the most safe place for resetting the overflow
+     counter - just _after_ we reset the timer. Depending
+     on the SOPC configuration, the counter may not be
+     stoppable and it doesn't make sense to assume that
+     there is any "safe" period before resetting. */
+
+  Timer_interrupts = 0;
+}
+
+/*
+ *  The following controls the behavior of benchmark_timer_read().
+ *
+ *  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      2      /* It typically takes 2 microseconds */
+                                 /* to start/stop the timer. */
+
+#define LEAST_VALID AVG_OVERHEAD /* Don't trust a value lower than this */
+
+benchmark_timer_t benchmark_timer_read( void )
+{
+  uint32_t timer_wraps;
+  uint32_t timer_snap;
+  uint32_t timer_ticks;
+  uint32_t total;
+
+  /* Hold timer */
+  TIMER_REGS->control = ALTERA_AVALON_TIMER_CONTROL_STOP_MSK;
+
+  /* Write to request snapshot of timer value */
+  TIMER_REGS->snap_lo = 0;
+  /* Get snapshot */
+  timer_snap = ((TIMER_REGS->snap_hi)<<16) | TIMER_REGS->snap_lo;
+  timer_wraps = Timer_interrupts;
+
+  /* Restart timer */
+  TIMER_REGS->control = ALTERA_AVALON_TIMER_CONTROL_START_MSK;
+
+#if TIMER_WRAPS_AFTER_1MS
+  timer_ticks = (TIMER_FREQ / 1000) - 1 - timer_snap;
+  total = timer_wraps * 1000;
+#else
+  timer_ticks = 0xFFFFFFFF - timer_snap;
+  total = timer_wraps * 0x80000000 / (TIMER_FREQ / 2000000L);
+#endif
+  total += timer_ticks / (TIMER_FREQ / 1000000L);
+
+  if(total < LEAST_VALID) return 0;
+
+  if(benchmark_timer_find_average_overhead != TRUE) total-= AVG_OVERHEAD;
+
+  return total;
+}
+
+void benchmark_timer_disable_subtracting_average_overhead(bool find_flag)
+{
+  benchmark_timer_find_average_overhead = find_flag;
+}