• Chen Yu's avatar
    cpufreq: intel_pstate: Get per-CPU max freq via MSR_HWP_CAPABILITIES if available · 6f67e060
    Chen Yu authored
    Currently, when turbo is disabled (either by BIOS or by the user),
    the intel_pstate driver reads the max non-turbo frequency from the
    package-wide MSR_PLATFORM_INFO(0xce) register.
    
    However, on asymmetric platforms it is possible in theory that small
    and big core with HWP enabled might have different max non-turbo CPU
    frequency, because MSR_HWP_CAPABILITIES is per-CPU scope according
    to Intel Software Developer Manual.
    
    The turbo max freq is already per-CPU in current code, so make
    similar change to the max non-turbo frequency as well.
    Reported-by: default avatarWendy Wang <wendy.wang@intel.com>
    Signed-off-by: default avatarChen Yu <yu.c.chen@intel.com>
    [ rjw: Subject and changelog edits ]
    Cc: 4.18+ <stable@vger.kernel.org> # 4.18+: a45ee4d4: cpufreq: intel_pstate: Change intel_pstate_get_hwp_max() argument
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    6f67e060
intel_pstate.c 78.9 KB