ableos/userland/bogomips.c
2022-06-02 06:00:26 -05:00

78 lines
1.4 KiB
C

// Utterly stolen from stack overflow
/*
* Standalone BogoMips program
*
* Based on code Linux kernel code in init/main.c and
* include/linux/delay.h
*
* For more information on interpreting the results, see the BogoMIPS
* Mini-HOWTO document.
*
* version: 1.3
* author: Jeff Tranter (Jeff_Tranter@Mitel.COM)
*/
#include <stdio.h>
#include <time.h>
#ifdef CLASSIC_BOGOMIPS
/* the original code from the Linux kernel */
static __inline__ void delay(int loops)
{
__asm__(".align 2,0x90\n1:\tdecl %0\n\tjns 1b": :"a" (loops):"ax");
}
#endif
#ifdef QNX_BOGOMIPS
/* version for QNX C compiler */
void delay(int loops);
#pragma aux delay = \
"l1:" \
"dec eax" \
"jns l1" \
parm nomemory [eax] modify exact nomemory [eax];
#endif
#ifdef PORTABLE_BOGOMIPS
/* portable version */
static void delay(int loops)
{
long i;
for (i = loops; i >= 0 ; i--)
;
}
#endif
int
main(void)
{
unsigned long loops_per_sec = 1;
unsigned long ticks;
printf("Calibrating delay loop.. ");
fflush(stdout);
while ((loops_per_sec <<= 1)) {
ticks = clock();
delay(loops_per_sec);
ticks = clock() - ticks;
if (ticks >= CLOCKS_PER_SEC) {
loops_per_sec = (loops_per_sec / ticks) * CLOCKS_PER_SEC;
printf("ok - %lu.%02lu BogoMips\n",
loops_per_sec/500000,
(loops_per_sec/5000) % 100
);
return 0;
}
}
printf("failed\n");
return -1;
}