Re: [PATCH v5 0/2] add SW BOOST support for CPPC
From: Rafael J. Wysocki
Date: Fri Jun 05 2020 - 08:22:46 EST
On Tue, Jun 2, 2020 at 7:16 AM Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
>
> On 30-05-20, 10:08, Xiongfeng Wang wrote:
> > ACPI spec 6.2 section 8.4.7.1 provide the following two CPC registers.
> >
> > "Highest performance is the absolute maximum performance an individual
> > processor may reach, assuming ideal conditions. This performance level
> > may not be sustainable for long durations, and may only be achievable if
> > other platform components are in a specific state; for example, it may
> > require other processors be in an idle state.
> >
> > Nominal Performance is the maximum sustained performance level of the
> > processor, assuming ideal operating conditions. In absence of an
> > external constraint (power, thermal, etc.) this is the performance level
> > the platform is expected to be able to maintain continuously. All
> > processors are expected to be able to sustain their nominal performance
> > state simultaneously."
> >
> > We can use Highest Performance as the max performance in boost mode and
> > Nomial Performance as the max performance in non-boost mode. If the
> > Highest Performance is greater than the Nominal Performance, we assume
> > SW BOOST is supported.
> >
> > Changelog:
> >
> > v4 -> v5:
> > add 'cpu_hotplug_lock' before calling '.set_boost'
> > v3 -> v4:
> > run 'boost_set_msr_each' for each CPU in the policy rather than
> > each CPU in the system for 'acpi-cpufreq'
> > add 'Suggested-by'
> >
> > Xiongfeng Wang (2):
> > cpufreq: change '.set_boost' to act on only one policy
> > CPPC: add support for SW BOOST
> >
> > drivers/cpufreq/acpi-cpufreq.c | 14 ++++++-----
> > drivers/cpufreq/cppc_cpufreq.c | 39 +++++++++++++++++++++++++++--
> > drivers/cpufreq/cpufreq.c | 57 +++++++++++++++++++++++-------------------
> > include/linux/cpufreq.h | 2 +-
> > 4 files changed, 77 insertions(+), 35 deletions(-)
>
> Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Both patches have been applied as 5.8-rc material with slightly
modified subjects and the changelog of patch [1/2] has been updated.
Thanks!