[PATCH 06/24] tools/power turbostat: Intel Xeon x200: fix erroneous bclk value

Tim Gardner tim.gardner at canonical.com
Wed Aug 24 20:49:35 UTC 2016

From: "Chrzaniuk, Hubert" <hubert.chrzaniuk at intel.com>

BugLink: http://bugs.launchpad.net/bugs/1591802

x200 does not enable any way to programmatically obtain bus clock
speed. Bclk for the architecture has a fixed value of 100 MHz.
At the same time x200 cannot be included in has_snb_msrs since
it does not support C7 idle state.

prior to this patch, MHz values reported on this chip
were erroneously calculated using bclk of 133MHz,
causing MHz values to be reported 33% higher than actual.

Signed-off-by: Hubert Chrzaniuk <hubert.chrzaniuk at intel.com>
Signed-off-by: Len Brown <len.brown at intel.com>
(cherry picked from commit 121b48bb77187cf2ed3053e147d2e6c1e864083c)
Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
 tools/power/x86/turbostat/turbostat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index e411cc4..652d08d 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -2697,7 +2697,7 @@ double slm_bclk(void)
 double discover_bclk(unsigned int family, unsigned int model)
-	if (has_snb_msrs(family, model))
+	if (has_snb_msrs(family, model) || is_knl(family, model))
 		return 100.00;
 	else if (is_slm(family, model))
 		return slm_bclk();

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