diff options
author | Peter Wemm <peter@FreeBSD.org> | 2005-12-13 19:08:55 +0000 |
---|---|---|
committer | Peter Wemm <peter@FreeBSD.org> | 2005-12-13 19:08:55 +0000 |
commit | 737429bc962ecabc5c530a8e648a231f66358b70 (patch) | |
tree | ab36666fbbf06a6153ec45cfe56905154beba4f5 /sys/isa | |
parent | e83f6bcb75fb0ca55a67121e07f2963e6af7f6e7 (diff) | |
download | src-737429bc962ecabc5c530a8e648a231f66358b70.tar.gz src-737429bc962ecabc5c530a8e648a231f66358b70.zip |
MFamd64 rev 1.223: Use the TSC to implement DELAY() if not marked broken
and it has been calibrated.
Notes
Notes:
svn path=/head/; revision=153384
Diffstat (limited to 'sys/isa')
-rw-r--r-- | sys/isa/atrtc.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/sys/isa/atrtc.c b/sys/isa/atrtc.c index 38b238f6dd92..7a75cfb0befc 100644 --- a/sys/isa/atrtc.c +++ b/sys/isa/atrtc.c @@ -64,6 +64,7 @@ __FBSDID("$FreeBSD$"); #include <sys/kernel.h> #include <sys/limits.h> #include <sys/module.h> +#include <sys/sched.h> #include <sys/sysctl.h> #include <sys/cons.h> #include <sys/power.h> @@ -288,7 +289,21 @@ DELAY(int n) int getit_calls = 1; int n1; static int state = 0; +#endif + + if (tsc_freq != 0 && !tsc_is_broken) { + uint64_t start, end, now; + sched_pin(); + start = rdtsc(); + end = start + (tsc_freq * n) / 1000000; + do { + now = rdtsc(); + } while (now < end || (now > start && end < start)); + sched_unpin(); + return; + } +#ifdef DELAYDEBUG if (state == 0) { state = 1; for (n1 = 1; n1 <= 10000000; n1 *= 10) |