From cbbf1259817896cd6339e7517404ba64aa85ed8d Mon Sep 17 00:00:00 2001 From: Ollie Lho Date: Wed, 17 Mar 2004 22:22:08 +0000 Subject: Move utility functions into new source files Corresponding to flashrom svn r6 and coreboot v2 svn r1428. --- udelay.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 udelay.c (limited to 'udelay.c') diff --git a/udelay.c b/udelay.c new file mode 100644 index 0000000..9674bbe --- /dev/null +++ b/udelay.c @@ -0,0 +1,43 @@ +#include +#include + +// count to a billion. Time it. If it's < 1 sec, count to 10B, etc. +unsigned long micro = 1; + +void myusec_delay(int time) +{ + volatile unsigned long i; + for(i = 0; i < time * micro; i++) + ; +} + +void myusec_calibrate_delay() +{ + int count = 1000; + unsigned long timeusec; + struct timeval start, end; + int ok = 0; + void myusec_delay(int time); + + printf("Setting up microsecond timing loop\n"); + while (!ok) { + //fprintf(stderr, "Try %d\n", count); + gettimeofday(&start, 0); + myusec_delay(count); + gettimeofday(&end, 0); + timeusec = 1000000 * (end.tv_sec - start.tv_sec ) + + (end.tv_usec - start.tv_usec); + //fprintf(stderr, "timeusec is %d\n", timeusec); + count *= 2; + if (timeusec < 1000000/4) + continue; + ok = 1; + } + + // compute one microsecond. That will be count / time + micro = count / timeusec; + + fprintf(stderr, "%ldM loops per second\n", (unsigned long)micro); + + +} -- cgit v1.1