Home
last modified time | relevance | path

Searched hist:"8 c69da293041352d15a2b6e8010c141822a416c5" (Results 1 – 1 of 1) sorted by relevance

/openbmc/linux/tools/power/x86/turbostat/
H A Dturbostat.cdiff 8c69da293041352d15a2b6e8010c141822a416c5 Tue Apr 27 21:51:57 CDT 2021 Chen Yu <yu.c.chen@intel.com> tools/power turbostat: Enable tsc_tweak for Elkhart Lake and Jasper Lake

It was found that on Elkhart Lake the TSC frequency is driven by
a separate crystal-clock domain, which is different from the
BCLK domain which includes mperf. This has result in small different
speed thus inconsistence between TSC and the mperf, which caused the
Busy% to be higher than 100%. On this platform it seems that the mperf
runs faster than tsc when the CPU is 100% utilized:
delta tsc(18815473183) < delta mperf(18958403680) for 10 seconds.

To align TSC with mperf, leverage the tsc_tweak mechanism introduced for
cores newer than Skylake, so that TSC and mperf would be calculated in
the same domain.

Reported-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>