forked from Imagelibrary/rtems
150 lines
4.2 KiB
C
150 lines
4.2 KiB
C
/*
|
|
* 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_interrupt_entry timer_interrupt;
|
|
|
|
static rtems_isr timerisr(void *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;
|
|
|
|
rtems_interrupt_entry_initialize(
|
|
&timer_interrupt,
|
|
timerisr,
|
|
NULL,
|
|
"handle timer interrupt"
|
|
);
|
|
rtems_interrupt_entry_install(
|
|
TIMER_VECTOR,
|
|
RTEMS_INTERRUPT_UNIQUE,
|
|
&timer_interrupt
|
|
);
|
|
|
|
/* 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;
|
|
}
|