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




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