[PATCH v3] turbostat: Read extended processor family from CPUID

From: Calvin Walton
Date: Fri Jul 27 2018 - 07:51:00 EST


This fixes the reported family on modern AMD processors (e.g. Ryzen,
which is family 0x17). Previously these processors all showed up as
family 0xf.

See the document
https://support.amd.com/TechDocs/56255_OSRR.pdf
section CPUID_Fn00000001_EAX for how to calculate the family
from the BaseFamily and ExtFamily values.

This matches the code in arch/x86/lib/cpu.c

Signed-off-by: Calvin Walton <calvin.walton@xxxxxxxxxx>
---

v3: Having just looked at the arch/x86/lib/cpu.c code again, I realized
that it *didn't* actually match - the kernel code uses family >= 6 for
applying the extended model number, while I was applying it only to
family == 6 or family >= 0xf. Change that to match for consistency.

v2: I'm still working on updating the RAPL patch on top of the changes for
v4.18, but this CPUID fix doesn't have to wait.

tools/power/x86/turbostat/turbostat.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index bd9c6b31a504..ed024deed36f 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -4031,7 +4031,9 @@ void process_cpuid()
family = (fms >> 8) & 0xf;
model = (fms >> 4) & 0xf;
stepping = fms & 0xf;
- if (family == 6 || family == 0xf)
+ if (family == 0xf)
+ family += (fms >> 20) & 0xff;
+ if (family >= 6)
model += ((fms >> 16) & 0xf) << 4;

if (!quiet) {
--
2.18.0