[PATCH 0/2] powernow-k8: fix incorrect value reported in cpuinfo_cur_freq

[Naga Chumbalkar]

The "cpuinfo_cur_freq" value reported in /sys is incorrect.

For example, on a 1P quad-core AMD platform (cores: 0,1,2,3) if you want the
"cpuinfo_cur_freq" for core2, you will actually get the value for core0. The
bug is apparent when all the cores are not at the same frequency.

Prior to 2.6.27.8, "cpuinfo_cur_freq" used to return the correct value because
query_current_values_with_pending_wait() obtained the P-state for core2 from
HW, and overwrote the "currpstate" for core0 with it.

However, that got broken with the commit:
a266d9f1253a38ec2d5655ebcd6846298b0554f4

This patch fixes the regression by:
- special-casing the AMD erratum 311 (discussed in the above commit) to AMD
Family 11h processors only
- cleaning up the way powernowk8_get() obtains the per-CPU data

 arch/x86/kernel/cpu/cpufreq/powernow-k8.c |   31 +++++++++++-----------------
 1 files changed, 12 insertions(+), 19 deletions(-)

Thanks,
- naga -


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/