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turbostat: fix Skylake server package C-states reporting

PATCH New Artem Bityutskiy 1 participant 1 message Jul 27, 2017

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Artem Bityutskiy

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PATCH 1/1 turbostat: fix Skylake server package C-states reporting

From: Artem Bityutskiy <[email protected]>

This patch fixes the problem of turbostat not reporting any package C-states on Skylake Xeon processor when the deepest package C-stated is configured as "no limit" in the UEFI firmware configuration menu.

The lowest 3 bits of the MSR_PKG_CST_CONFIG_CONTROL (0x000000e2) register contain 7 in this case, meaning "No Package C state limits" (see Intel SDM, vol 4, Table 2-41 - MSRs Supported by Intel® Xeon® Processor Scalable Family with DisplayFamily_DisplayModel 06_55H).

The problem was that turbostat's internal array of supported package C-sates (skx_pkg_cstate_limits) marked position #7 as "PCLRSV" (reserved), instead of "PCLUNL" (not limited). Instead, position #8 was incorrectly marked as "PCLUNL" (probably due to a typo).

This patch fixes the issue by marking position #7 as "not limited", and position #8 as "reserved".

Signed-off-by Artem Bityutskiy <[email protected]>
---
 turbostat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
turbostat.c +1 -1
index 6c185a9..1c4d3e2 100644
@@ -1816,7 +1816,7 @@ int slv_pkg_cstate_limits[16] = {PCL__0, PCL__1, PCLRSV, PCLRSV, PCL__4, PCLRSV,
 int amt_pkg_cstate_limits[16] = {PCLUNL, PCL__1, PCL__2, PCLRSV, PCLRSV, PCLRSV, PCL__6, PCL__7, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV};
 int phi_pkg_cstate_limits[16] = {PCL__0, PCL__2, PCL_6N, PCL_6R, PCLRSV, PCLRSV, PCLRSV, PCLUNL, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV};
 int bxt_pkg_cstate_limits[16] = {PCL__0, PCL__2, PCLUNL, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV};
-int skx_pkg_cstate_limits[16] = {PCL__0, PCL__2, PCL_6N, PCL_6R, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLUNL, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV};
+int skx_pkg_cstate_limits[16] = {PCL__0, PCL__2, PCL_6N, PCL_6R, PCLRSV, PCLRSV, PCLRSV, PCLUNL, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV, PCLRSV};
 
 
 static void
Signature · 1 line
2.9.3