Messages in this thread | | | Subject | Re: [PATCH V3] SKL intel_pstate update MSR values when changing governors | From | Srinivas Pandruvada <> | Date | Tue, 24 Nov 2015 08:27:32 -0800 |
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On Tue, 2015-11-24 at 17:36 +0100, Rafael J. Wysocki wrote: > On Tuesday, November 24, 2015 07:57:42 AM Srinivas Pandruvada wrote: > > On Tue, 2015-11-24 at 15:28 +0100, Rafael J. Wysocki wrote: > > > On Monday, November 23, 2015 05:17:36 PM Srinivas Pandruvada > > > wrote: > > > > On Tue, 2015-11-24 at 02:09 +0100, Rafael J. Wysocki wrote: > > > > > Hi, > > > > > > > > > > On Sat, Nov 21, 2015 at 1:16 AM, Srinivas Pandruvada > > > > > <srinivas.pandruvada@linux.intel.com> wrote: > > > > > > > > > > > > [cut] > > > > > > > > > > > > > > > For more information on the MSR values for SKL please > > > > > > > visit > > > > > > > ISDM under Managing HWP. > > > > > > > > > > > > > > Signed-off-by: Alexandra Yates < > > > > > > > alexandra.yates@linux.intel.com> > > > > > > > > > > > > Acked-by: Srinivas Pandruvada < > > > > > > srinivas.pandruvada@linux.intel.com> > > > > > > > > > > > > > > --- > > > > > > > drivers/cpufreq/intel_pstate.c | 2 ++ > > > > > > > 1 file changed, 2 insertions(+) > > > > > > > > > > > > > > diff --git a/drivers/cpufreq/intel_pstate.c > > > > > > > b/drivers/cpufreq/intel_pstate.c > > > > > > > index 2e31d09..0eeb7da 100644 > > > > > > > --- a/drivers/cpufreq/intel_pstate.c > > > > > > > +++ b/drivers/cpufreq/intel_pstate.c > > > > > > > @@ -1242,6 +1242,8 @@ static int > > > > > > > intel_pstate_set_policy(struct > > > > > > > cpufreq_policy *policy) > > > > > > > policy->max >= policy->cpuinfo.max_freq) { > > > > > > > pr_debug("intel_pstate: set > > > > > > > performance\n"); > > > > > > > limits = &performance_limits; > > > > > > > + if (hwp_active) > > > > > > > + intel_pstate_hwp_set(); > > > > > > > > > > Honestly, I'm not really sure how this is matching the > > > > > changelog. > > > > > > > > > > What it does is to ensure that the correct limits are used > > > > > when > > > > > in the > > > > > HWP mode too as far as I can say. Is my understanding > > > > > correct > > > > > here? > > > > Yes. > > > > > > OK > > > > > > But if we make the "performance" limits take effect here, it will > > > effectively > > > make HWP use min = max = 100%, right? Is that what we want to > > > happen > > > here? > > Yes. intel_pstate_hwp_set() uses limits->min_perf_pct and limits > > ->max_perf_pct to set HWP limits. Here these will be set to 100%. > > OK, so that's the intended behavior of "performance" in the HWP case, > right? > Yes. > I'll apply this patch, but I'm going to write a new changelog for it, > then. Sure.
Thanks, Srinivas
> > Thanks, > Rafael >
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