diff options
author | Ollie Lho <ollie@sis.com.tw> | 2004-03-17 22:22:08 +0000 |
---|---|---|
committer | Ollie Lho <ollie@sis.com.tw> | 2004-03-17 22:22:08 +0000 |
commit | 22535ef434b6589fa02be5785ffe8e8db6c738fb (patch) | |
tree | 96c21cf62ad8fd400edd11e6e68cb75fdbd6d6bf /udelay.c | |
parent | fe592a8af971f6f9f5f90b82ea8bf6841af51f48 (diff) | |
download | flashrom-22535ef434b6589fa02be5785ffe8e8db6c738fb.zip flashrom-22535ef434b6589fa02be5785ffe8e8db6c738fb.tar.gz |
Move utility functions into new source files
Corresponding to flashrom svn r6 and coreboot v2 svn r1428.
Diffstat (limited to 'udelay.c')
-rw-r--r-- | udelay.c | 43 |
1 files changed, 43 insertions, 0 deletions
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 <sys/time.h> +#include <stdio.h> + +// 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); + + +} |