performance_test.c

   1 /*
   2  * author: Daniel Otte
   3  * email:  daniel.otte@rub.de
   4  * license: GPLv3
   5  *
   6  *
   7  **/
   8
   9 #include "config.h"
  10 #include <stdint.h>
  11 #include <stdlib.h>
  12 #include <avr/io.h>
  13 #include <avr/interrupt.h>
  14 #include "performance_test.h"
  15
  16
  17 #ifdef ATMEGA644
  18         #define TIMSK TIMSK1
  19 #endif
  20
  21
  22
  23 uint32_t ovfcounter;
  24
  25 uint16_t const_overhead=0;
  26 uint16_t int_overhead=0;
  27
  28 ISR(TIMER1_OVF_vect){
  29         ovfcounter++;
  30 }
  31
  32 void calibrateTimer(void){
  33         startTimer(1);
  34         stopTimer();
  35         const_overhead = TCNT1;
  36         startTimer(1);
  37         TCNT1=0xFFFE;
  38         ; ; ; ;
  39 //      asm volatile("NOP\n"::); asm volatile("NOP\n"::);
  40         stopTimer();
  41         int_overhead = TCNT1;
  42 }
  43
  44 void startTimer(uint8_t granularity){
  45         TCCR1B = 0; /* stop timer */
  46         TCNT1  = 0;
  47         ovfcounter = 0;
  48         TCCR1A = 0x00;
  49         TIMSK &= 0xC3;
  50         TIMSK |= _BV(TOIE1); /* enable TOIE1 */
  51         TCCR1B = granularity & 0x7;     /* start timer */
  52 }
  53
  54 uint64_t stopTimer(void){
  55         TCCR1B = 0; /* stop timer */
  56         uint64_t ret;
  57         ret = (ovfcounter<<16) | TCNT1;
  58         ret -= const_overhead;
  59         ret -= ovfcounter * int_overhead;
  60         return ret;
  61 }
  62
  63 void getOverhead(uint16_t* constoh, uint16_t* intoh){
  64         *constoh = const_overhead;
  65         *intoh   = int_overhead;
  66 }
  67
  68
  69
  70