Commit 8c69da29 authored by Chen Yu's avatar Chen Yu Committed by Len Brown

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: default avatarZhang Rui <rui.zhang@intel.com>
Signed-off-by: default avatarChen Yu <yu.c.chen@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 1e3ec5cd
......@@ -5440,7 +5440,7 @@ void process_cpuid()
if (!quiet)
dump_sysfs_pstate_config();
if (has_skl_msrs(family, model))
if (has_skl_msrs(family, model) || is_ehl(family, model))
calculate_tsc_tweak();
if (!access("/sys/class/drm/card0/power/rc6_residency_ms", R_OK))
......
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