Messages in this thread | | | From | Xiongfeng Wang <> | Subject | [RFC PATCH v2 0/3] add SW BOOST support for CPPC | Date | Mon, 18 May 2020 15:10:05 +0800 |
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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.
Xiongfeng Wang (3): cpufreq: handle the return value of '.set_boost()' properly cpufreq: export 'cpufreq_policy_list' and make macro 'for_each_*_policy' public CPPC: add support for SW BOOST
drivers/cpufreq/cppc_cpufreq.c | 42 ++++++++++++++++++++++++++++++++++++++++-- drivers/cpufreq/cpufreq.c | 21 ++++++--------------- include/linux/cpufreq.h | 14 ++++++++++++++ 3 files changed, 60 insertions(+), 17 deletions(-)
-- 1.7.12.4
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