> > | > There is a calibration step in the driver to determine the clock rate of th > | e > | > AC97 link. What you are seeing is the calibration step failing and setting > | a > | > bogus ac97 link rate. I took a cursory look a couple of weeks back and it > | > smelt like the timecounter initialization point changed, but haven't gotten > | > | > around to looking closer and fixing the driver. > > It's definitely nothing to do with the timecounter - quick test on other h/w > along similar lines. I don't access to an ich board to test on - it's > probably obvious, but I'm not seeing it just now with visual inspection...
It doesn't look like it is the timecounters. I just added some printfs and it looks like this: pcm0: measured ac97 link rate at 512000000 Hz t1 1.098359, t2 1.098363 ociv 0, nciv 1, bytes 8192 tsc1 445813142, tsc2 445821922, diff 8780 The tsc values are just from rdtsc(), I added tsc1 = rdtsc() just above the first microtime() and tsc2 just after the last. My machine is a 1.8G P4 (ICH2), so the timecounter values seem correct. I have kernel around the middle of Feb that gets the value right and one from March 4 that gets it all wrong. John -- John Hay -- [EMAIL PROTECTED] / [EMAIL PROTECTED] _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "[EMAIL PROTECTED]"
