[PATCH RESEND v10 0/7] cpufreq:boost: CPU Boost mode support

Lukasz Majewski
2013-12-02T12:19:36Z

This patch series introduces support for CPU overclocking technique
called Boost.

It is a follow up of a LAB governor proposal. Boost is a LAB component:
http://thread.gmane.org/gmane.linux.kernel/1484746/match=cpufreq

Boost unifies hardware based solution (e.g. Intel Nehalem) with
software oriented one (like the one done at Exynos).
For this reason cpufreq/freq_table code has been reorganized to include
common code.

Important design decisions:
- Boost related code is compiled-in unconditionally to cpufreq core and
disabled by default. The cpufreq_driver is responsibile for setting
boost_supported flag and providing set_boost callback(if HW support
is needed). For software managed boost, special Kconfig flag -
CONFIG_CPU_FREQ_BOOST_SW has been defined. It will be selected only
when a target platform has thermal framework properly configured.

- struct cpufreq_driver has been extended with boost related fields:
-- boost_supported - when driver supports boosting
-- boost_enabled - boost state
-- set_boost - callback to function, which is necessary to
enable/disable boost

- Boost sysfs attribute (/sys/devices/system/cpu/cpufreq/boost) is visible
_only_ when cpufreq driver supports Boost.

- No special spin_lock for Boost was created. The one from cpufreq core
was reused.

- The Boost code doesn't rely on any policy. When boost state is changed,
then the policy list is iterated and proper adjustements are done.

- To improve safety level, the thermal framework is also extended to disable
software boosting, when thermal trip point is reached. After cooling down
the boost can be enabled again. This emulates behaviour similar to HW
managed boost (like x86)

Tested at HW:
Exynos 4412 3.13-rc2 Linux
Intel Core i7-3770 3.13-rc2 Linux

Above patches were posted on top of kernel_pm/bleeding-edge
(SHA1: 9483a9f69d5c8f83f1723361bf8340ddfb6475b4)

Lukasz Majewski (7):
cpufreq: Add boost frequency support in core
cpufreq:acpi:x86: Adjust the acpi-cpufreq.c code to work with common
boost solution
cpufreq:boost:Kconfig: Provide support for software managed BOOST
cpufreq:exynos:Extend Exynos cpufreq driver to support boost
framework
Documentation:cpufreq:boost: Update BOOST documentation
cpufreq:exynos4x12: Change L0 driver data to CPUFREQ_BOOST_FREQ
thermal:exynos:boost: Automatic enable/disable of BOOST feature (at
Exynos4412)

Documentation/cpu-freq/boost.txt | 26 +++----
drivers/cpufreq/Kconfig | 4 +
drivers/cpufreq/Kconfig.arm | 15 ++++
drivers/cpufreq/acpi-cpufreq.c | 86 +++++++--------------
drivers/cpufreq/cpufreq.c | 118 ++++++++++++++++++++++++++++-
drivers/cpufreq/exynos-cpufreq.c | 3 +
drivers/cpufreq/exynos4x12-cpufreq.c | 2 +-
drivers/cpufreq/freq_table.c | 56 ++++++++++++--
drivers/thermal/samsung/exynos_tmu_data.c | 47 ++++++++++++
include/linux/cpufreq.h | 24 ++++++
10 files changed, 302 insertions(+), 79 deletions(-)

--
1.7.10.4