History log of /drivers/cpufreq/Makefile
Revision Date Author Comments
efb5961d4ca9c5cfbfea61b46fa16074e44effbd 22-Jun-2010 Mike Chan <mike@android.com> cpufreq: interactive: New 'interactive' governor

This governor is designed for latency-sensitive workloads, such as
interactive user interfaces. The interactive governor aims to be
significantly more responsive to ramp CPU quickly up when CPU-intensive
activity begins.

Existing governors sample CPU load at a particular rate, typically
every X ms. This can lead to under-powering UI threads for the period of
time during which the user begins interacting with a previously-idle system
until the next sample period happens.

The 'interactive' governor uses a different approach. Instead of sampling
the CPU at a specified rate, the governor will check whether to scale the
CPU frequency up soon after coming out of idle. When the CPU comes out of
idle, a timer is configured to fire within 1-2 ticks. If the CPU is very
busy from exiting idle to when the timer fires then we assume the CPU is
underpowered and ramp to MAX speed.

If the CPU was not sufficiently busy to immediately ramp to MAX speed, then
the governor evaluates the CPU load since the last speed adjustment,
choosing the highest value between that longer-term load or the short-term
load since idle exit to determine the CPU speed to ramp to.

A realtime thread is used for scaling up, giving the remaining tasks the
CPU performance benefit, unlike existing governors which are more likely to
schedule rampup work to occur after your performance starved tasks have
completed.

The tuneables for this governor are:
/sys/devices/system/cpu/cpufreq/interactive/min_sample_time:
The minimum amount of time to spend at the current frequency before
ramping down. This is to ensure that the governor has seen enough
historic CPU load data to determine the appropriate workload.
Default is 80000 uS.
/sys/devices/system/cpu/cpufreq/interactive/go_maxspeed_load
The CPU load at which to ramp to max speed. Default is 85.

Change-Id: Ib2b362607c62f7c56d35f44a9ef3280f98c17585
Signed-off-by: Mike Chan <mike@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Bug: 3152864
bbcf071969b20f356877c8067986be0a2dcaa2aa 09-Sep-2014 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: cpu0: rename driver and internals to 'cpufreq_dt'

The naming convention of this driver was always under the scanner, people
complained that it should have a more generic name than cpu0, as it manages all
CPUs that are sharing clock lines.

Also, in future it will be modified to support any number of clusters with
separate clock/voltage lines.

Lets rename it to 'cpufreq_dt' from 'cpufreq_cpu0'.

Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
5a90af67c2126fe1d04ebccc1f8177e6ca70d3a9 08-Jul-2014 Prabhakar Lad <prabhakar.csengg@gmail.com> cpufreq: Makefile: fix compilation for davinci platform

Since commtit 8a7b1227e303 (cpufreq: davinci: move cpufreq driver to
drivers/cpufreq) this added dependancy only for CONFIG_ARCH_DAVINCI_DA850
where as davinci_cpufreq_init() call is used by all davinci platform.

This patch fixes following build error:

arch/arm/mach-davinci/built-in.o: In function `davinci_init_late':
:(.init.text+0x928): undefined reference to `davinci_cpufreq_init'
make: *** [vmlinux] Error 1

Fixes: 8a7b1227e303 (cpufreq: davinci: move cpufreq driver to drivers/cpufreq)
Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
a0dd7b79657bd6644b914d16ce7f23468c44a7b4 05-May-2014 Nishanth Menon <nm@ti.com> PM / OPP: Move cpufreq specific OPP functions out of generic OPP library

CPUFreq specific helper functions for OPP (Operating Performance Points)
now use generic OPP functions that allow CPUFreq to be be moved back
into CPUFreq framework. This allows for independent modifications
or future enhancements as needed isolated to just CPUFreq framework
alone.

Here, we just move relevant code and documentation to make this part of
CPUFreq infrastructure.

Cc: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
b3d627a5f2bf1a9a486f65af6f7c2ce0e09b3d12 31-Mar-2014 Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> cpufreq: powernv: cpufreq driver for powernv platform

Backend driver to dynamically set voltage and frequency on
IBM POWER non-virtualized platforms. Power management SPRs
are used to set the required PState.

This driver works in conjunction with cpufreq governors
like 'ondemand' to provide a demand based frequency and
voltage setting on IBM POWER non-virtualized platforms.

PState table is obtained from OPAL v3 firmware through device
tree.

powernv_cpufreq back-end driver would parse the relevant device-tree
nodes and initialise the cpufreq subsystem on powernv platform.

The code was originally written by svaidy@linux.vnet.ibm.com. Over
time it was modified to accomodate bug-fixes as well as updates to the
the cpu-freq core. Relevant portions of the change logs corresponding
to those modifications are noted below:

* The policy->cpus needs to be populated in a hotplug-invariant
manner instead of using cpu_sibling_mask() which varies with
cpu-hotplug. This is because the cpufreq core code copies this
content into policy->related_cpus mask which should not vary on
cpu-hotplug. [Authored by srivatsa.bhat@linux.vnet.ibm.com]

* Create a helper routine that can return the cpu-frequency for the
corresponding pstate_id. Also, cache the values of the pstate_max,
pstate_min and pstate_nominal and nr_pstates in a static structure
so that they can be reused in the future to perform any
validations. [Authored by ego@linux.vnet.ibm.com]

* Create a driver attribute named cpuinfo_nominal_freq which creates
a sysfs read-only file named cpuinfo_nominal_freq. Export the
frequency corresponding to the nominal_pstate through this
interface.

Nominal frequency is the highest non-turbo frequency for the
platform. This is generally used for setting governor policies
from user space for optimal energy efficiency. [Authored by
ego@linux.vnet.ibm.com]

* Implement a powernv_cpufreq_get(unsigned int cpu) method which will
return the current operating frequency. Export this via the sysfs
interface cpuinfo_cur_freq by setting powernv_cpufreq_driver.get to
powernv_cpufreq_get(). [Authored by ego@linux.vnet.ibm.com]

[Change log updated by ego@linux.vnet.ibm.com]

Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
47ac9aa165540b43deb3582f186073884de1cf3b 29-Oct-2013 Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> cpufreq: arm_big_little: add vexpress SPC interface driver

The TC2(i.e. CA15_A7) Versatile Express has external Cortex M3 based
power controller which is responsible for CPU DVFS and SPC provides
the interface for the same.

This patch adds a tiny interface driver to check if OPPs are
initialised by SPC platform code and register the arm_big_little
cpufreq driver.

Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
3bc28ab6da039f8020bbcea8e832b63a900bdb66 03-Oct-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: remove CONFIG_CPU_FREQ_TABLE

CONFIG_CPU_FREQ_TABLE will be always enabled when cpufreq framework is used, as
cpufreq core depends on it. So, we don't need this CONFIG option anymore as it
is not configurable. Remove CONFIG_CPU_FREQ_TABLE and update its users.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
61c63e5ed3b9c472899d7152e961f2ffaafcf5a0 05-Jun-2013 Stratos Karafotis <stratosk@semaphore.gr> cpufreq: Remove unused APERF/MPERF support

The target frequency calculation method in the ondemand governor has
changed and it is now independent of the measured average frequency.
Consequently, the APERF/MPERF support in cpufreq is not used any
more, so drop it.

[rjw: Changelog]
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
dbb8d76e5ed9bb7f33a092f4aa5b28d8b1c872a4 11-Jun-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: tegra: create CONFIG_ARM_TEGRA_CPUFREQ

currently Tegra cpufreq driver gets built based on ARCH_TEGRA, which doesn't
depend on nor select CPU_FREQ itself, so:

select CPU_FREQ_TABLE if CPU_FREQ

... isn't guaranteed to fire.

The correct solution seems to be:

* Add CONFIG_ARM_TEGRA_CPUFREQ to drivers/cpufreq/Kconfig.arm.
* Make that Kconfig option selct CPU_FREQ_TABLE.
* Make that Kconfig option be def_bool ARCH_TEGRA.
* Modify drivers/cpufreq/Makefile to build tegra-cpufreq.c based on that.
* Remove all the cpufreq-related stuff from arch/arm/mach-tegra/Kconfig.

That way, tegra-cpufreq.c can't be built if !CPU_FREQ, and Tegra's
cpufreq works the same way as all the other cpufreq drivers.

This patch does it.

Suggested-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
96070b1db1ffb837d59b501e743ffbda82b6a9d9 12-Jun-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: blackfin: enable driver for CONFIG_BFIN_CPU_FREQ

By mistake blackfin's cpufreq driver is enabled when CONFIG_BLACKFIN was
present, whereas it should have been enabled only when CONFIG_BFIN_CPU_FREQ is
present.

Fix it.

Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
7fb6a53db58c729ff470095371f431b6d66c527b 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: powerpc: move cpufreq driver to drivers/cpufreq

Move cpufreq driver of powerpc platform to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
defa4c738aa90e29e91eff43b0c1b3198367ce9c 05-Jun-2013 Tang Yuantian <yuantian.tang@freescale.com> cpufreq: powerpc: Add cpufreq driver for Freescale e500mc SoCs

Add cpufreq driver for Freescale e500mc, e5500 and e6500 SoCs
which are capable of changing the CPU frequency dynamically

Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
f023f8dd59bf93e29e9b9bd98a92eeef43b1a32a 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: s3c24xx: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of Samsung's ARM based
s3c24xx platform to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
49d7b5bfb79cd5f8141a2998e2f4003d0ed65e5c 08-Apr-2013 Amit Daniel Kachhap <amit.daniel@samsung.com> cpufreq: exynos: Add cpufreq driver for exynos5440

This patch adds dvfs support for exynos5440 SOC. This soc has 4 cores and
they scale at same frequency. The nature of exynos5440 clock controller is
different from previous exynos controllers so not using the common exynos
cpufreq framework. The major difference being interrupt notification for
frequency change. Also, OPP library is used for device tree parsing to get
different parameters like frequency, voltage etc. Since the opp library sorts
the frequency table in ascending order so they are again re-arranged in
descending order. This will have one-to-one mapping with the clock controller
state management logic.

Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
9c5320c8ea8b8423edca2c40cd559f1ce9496dab 04-Apr-2013 Jacob Shin <jacob.shin@amd.com> cpufreq: AMD "frequency sensitivity feedback" powersave bias for ondemand governor

Future AMD processors, starting with Family 16h, can provide software
with feedback on how the workload may respond to frequency change --
memory-bound workloads will not benefit from higher frequency, where
as compute-bound workloads will. This patch enables this "frequency
sensitivity feedback" to aid the ondemand governor to make better
frequency change decisions by hooking into the powersave bias.

Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Acked-by: Thomas Renninger <trenn@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6eb1c377423572374518f5be93214d139d113090 25-Mar-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: powerpc/platforms/cell: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of powerpc platforms/cell to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
764295ae675bb252de3637e36a6602a9aed7de6b 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: sparc: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of SPARC architecture to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
73cc9c8cac3f86ae4efebf001b68dcecc00b0017 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: unicore2: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of UNICORE-2 architecture to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7258267e56325d41f468eb650b6c23f697201645 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: sh: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of SUPERH architecture to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7a9989356b23fa2c7731632d3b575c53c1ac8bce 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: mips: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of MIPS architecture to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ab423e435f1eafdb9a071fe8a9942b2522d09d2d 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: ia64: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of IA64 architecture to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8e8aa95a2b0b2b0184b3b72b324a6145362720bd 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: cris: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq drivers of CRIS architecture to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
d5cc9901ca05a816bd05b69699a1ba5358871ad5 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: blackfin: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of BLACKFIN architecture to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Steven Miao <realmz6@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
81c720c90e6fbda5a1f53f932035de899f27adb6 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: AVR32: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of AVR32 based at32ap platform to
drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
59a2e613d07fbd592ff711c87458eabcf9c98902 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: sa11x0: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of ARM based sa11x0 platform to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
b7e614c8bf5c898b172d7dfed9853fdda35be5cc 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: integrator: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of ARM based integrator platform to
drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cffc96eb4f91ba0f974b352a28b15f84950bd776 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: pxa2xx: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of ARM based pxa2xx platform to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
adde904b445eedf7ad6a8451a416c8080472c4c7 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: pxa3xx: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of ARM based pxa3xx platform to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8a7b1227e303d7e927214ee0f260041aef44bb58 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: davinci: move cpufreq driver to drivers/cpufreq

This patch moves cpufreq driver of ARM based davinci platform to
drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ceff98e3338cc53e31491aa8db395dd66327b210 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: tegra: Move driver to drivers/cpufreq

This patch moves cpufreq driver of ARM based tegra platform to drivers/cpufreq.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
a0ea048a6f72fbe9083b52ba26cd642e23ca026c 04-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: ARM: Arrange drivers in alphabetical order

Normally we keep drivers in alphabetical inside Kconfig and Makefile and over
time this was broken for ARM cpufreq drivers. Fix it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8a67f0ef2b684b34162d39e8f436fe39e9635a19 01-Apr-2013 Viresh Kumar <viresh.kumar@linaro.org> cpufreq: ARM big LITTLE: Add generic cpufreq driver and its DT glue

big LITTLE is ARM's new Architecture focussing power/performance needs of modern
world. More information about big LITTLE can be found here:

http://www.arm.com/products/processors/technologies/biglittleprocessing.php
http://lwn.net/Articles/481055/

In order to keep cpufreq support for all big LITTLE platforms simple/generic,
this patch tries to add a generic cpufreq driver layer for all big LITTLE
platforms.

The driver is divided into two parts:
- Core driver: Generic and shared across all big LITTLE SoC's
- Glue drivers: Per platform drivers providing ops to the core driver

This patch adds in a generic glue driver which would extract information from
Device Tree.

Future SoC's can either reuse the DT glue or write their own depending on the
need.

Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2a4bd9f0db24ba14c8b38777d77add2682233c79 05-Feb-2013 Andrew Lunn <andrew@lunn.ch> cpufreq: kirkwood: Add a cpufreq driver for Marvell Kirkwood SoCs

The Marvell Kirkwood SoCs have simple cpufreq support in hardware. The
CPU can either use the a high speed cpu clock, or the slower DDR
clock. Add a driver to swap between these two clock sources.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
93f0822dff5dae2f0a2645f16300c14af41ca777 06-Feb-2013 Dirk Brandewie <dirk.brandewie@gmail.com> cpufreq/x86: Add P-state driver for sandy bridge.

Add a P-state driver for the Intel Sandy bridge processor. In cpufreq
terminology this driver implements a scaling driver with an internal
governor.

When built into the the kernel this driver will be the preferred
scaling driver for Sandy bridge processors.

In addition to the interfaces provided by the cpufreq subsystem for
controlling scaling drivers. The user may control the behavior of the
driver via three sysfs files located in
"/sys/devices/system/cpu/intel_pstate".

max_perf_pct: limits the maximum P state that will be requested by
the driver stated as a percentage of the avail performance.

min_perf_pct: limits the minimum P state that will be requested by
the driver stated as a percentage of the avail performance.

no_turbo: limits the driver to selecting P states below the turbo
frequency range.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
1dd538f072f0b7ba327613253d41ebb329c6d490 04-Feb-2013 Shawn Guo <shawn.guo@linaro.org> cpufreq: add imx6q-cpufreq driver

Add an imx6q-cpufreq driver for Freescale i.MX6Q SoC to handle the
hardware specific frequency and voltage scaling requirements.

The driver supports module build and is instantiated by the platform
device/driver mechanism, so that it will not be instantiated on other
platforms, as IMX is built with multiplatform support.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6754f556103be5bd172263b1075ddbb7157afbad 28-Jan-2013 Mark Langsdorf <mark.langsdorf@calxeda.com> cpufreq / highbank: add support for highbank cpufreq

Highbank processors depend on the external ECME to perform voltage
management based on a requested frequency. Communication between the
A9 cores and the ECME happens over the pl320 IPC channel.

Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
741220ea86709717e1d392b5a9617dfe90cd3802 20-Jan-2013 Borislav Petkov <bp@suse.de> cpufreq: Make acpi-cpufreq link first

Now that the majority of x86 CPUs out there are supported by
acpi-cpufreq, we want it to load first and, in the AMD case, drop to
powernow-k8 only on K8s. If, however, both powernow-k8 and acpi-cpufreq
are built-in, the link order matters. Correct that.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
edb10c11c9af64efc8cdb001ada9792e0b2eef42 10-Dec-2012 Lee Jones <lee.jones@linaro.org> cpufreq: Give driver used for dbx500 family a more generic name

This driver doesn't only handle cpufreq functionality for the
db8500 anymore. There are new variants which rely on it too.
Let's make the name a bit more generic.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
1e15f295408e21873dba5fdf17efcbd05fcb6729 29-Dec-2012 Larry Finger <Larry.Finger@lwfinger.net> cpufreq / governor: Fix problem with cpufreq_ondemand or cpufreq_conservative

Since commit 2aacdff entitled "cpufreq: Move common part from governors
to separate file", whenever the drivers that depend on this new file
(cpufreq_ondemand or cpufreq_conservative) are built as modules, a new
module named cpufreq_governor is created because the Makefile includes
cpufreq_governor.o twice. As drivers/cpufreq/cpufreq_governor.c contains no
MODULE directives, the resulting module has no license specified, which
results in logging of a "module license 'unspecified' taints kernel". In
addition, a number of globals are exported GPL only, and are therefore
not available. This fix establishes a new boolean configuration variable
that forces cpufreq_governor.o to be linked into the kernel whenever
either cpufreq_ondemand or cpufreq_conservative is selected.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
420993221175a45db5af012c53fd2fef4d9533dc 27-Nov-2012 Deepak Sikri <deepak.sikri@st.com> cpufreq: SPEAr: Add CPUFreq driver

SPEAr is an ARM based family of SoCs. This patch adds in support of cpufreq
driver for SPEAr SoCs. It is supported via DT only and so bindings are present
in binding document.

Signed-off-by: Deepak Sikri <deepak.sikri@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2aacdfff9c6958723aa5076003247933cefc32ea 23-Oct-2012 viresh kumar <viresh.kumar@linaro.org> cpufreq: Move common part from governors to separate file, v2

Multiple cpufreq governers have defined similar get_cpu_idle_time_***()
routines. These routines must be moved to some common place, so that all
governors can use them.

So moving them to cpufreq_governor.c, which seems to be a better place for
keeping these routines.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
95ceafd46359dfd901f9d3b881b33d3036e4b0ce 06-Sep-2012 Shawn Guo <shawn.guo@linaro.org> cpufreq: Add a generic cpufreq-cpu0 driver

It adds a generic cpufreq driver for CPU0 frequency management based on
clk, regulator, OPP and device tree support. It can support both
uniprocessor (UP) and those symmetric multiprocessor (SMP) systems which
share clock and voltage across all CPUs.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: AnilKumar Ch <anilkumar@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
e1f0b8e9b04a262834ed111e605e5d215685dfab 04-Sep-2012 Matthew Garrett <mjg@redhat.com> cpufreq: Remove support for hardware P-state chips from powernow-k8

These chips are now supported by acpi-cpufreq, so we can delete all the
code handling them.

Andre: Tighten the deprecation warning message. Trigger load of
acpi-cpufreq and let the load of the module finally fail.
This avoids the problem of users ending up without any cpufreq support
after the transition.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
562a6cbe1cf2edf0a87a659eb26095400322430e 10-Mar-2012 Jaecheol Lee <jc.lee@samsung.com> EXYNOS5250: Add support cpufreq for EXYNOS5250

This patch adds support cpufreq for EXYNOS5250 SoC. Basically,
the exynos-cpufreq.c is used commonly and exynos5250-cpufreq.c
is used for EXYNOS5250(two Cortex-A15 cores) SoC.

Signed-off-by: Jaecheol Lee <jc.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
a35c50510dd4d20a9275a0d3d16b859d11b35606 10-Mar-2012 Jaecheol Lee <jc.lee@samsung.com> EXYNOS4X12: Add support cpufreq for EXYNOS4X12

This patch adds support cpufreq for EXYNOS4X12 SoCs. Basically,
the exynos-cpufreq.c is used commonly and exynos4x12-cpufreq.c
is used for EXYNOS4212(two Cortex-A9 cores) and EXYNOS4412(four
Cortex-A9 cores) SoCs.

Signed-off-by: Jaecheol Lee <jc.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
34ee55075265d68ca858f2426e165733664385b4 16-Feb-2012 Heiko Stübner <heiko@sntech.de> [CPUFREQ] Add S3C2416/S3C2450 cpufreq driver

The S3C2416/S3C2450 SoCs support two sources for the armclk.

The first source is the so called armdiv which divides the msysclk down
to provide necessary cpu rates. In this mode the core voltage must be
always at 1.3V. The frequency from the armdiv is not allowed to be
lower than the hclk frequency.

In the second mode the armclk can be sourced directly from the hclk in
the so called "dynamic voltags scaling" (dvs) mode. Here the armdiv
isn't used at all. Also in this mode the core voltage may be lowered.
Existing hardware and tests with it suggest 1.0V as sufficient.

When changing the clock source to the armdiv from the hclk, the SoC
shows stability issues if the new frequency is higher than the current
hclk frequency. Hence the driver always forces the armdiv to the hclk
frequency before the source change and lets the cpufreq issue another
set_target call for higher frequencies.

To mark the hclk frequency as lower as the corresponding armdiv
frequency it is set 1MHz below the real frequency. This lets the cpufreq
framework change between 133MHz based on hclk and 133MHz based on armdiv
at will.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Andrey Gusakov <dron0gus@gmail.com>
Signed-off-by: Dave Jones <davej@redhat.com>
b09db45c56c299438a09b85c06067d7dcd951ea4 15-Feb-2012 Russell King <rmk+kernel@arm.linux.org.uk> cpufreq: OMAP driver depends CPUfreq tables

The OMAP driver depends on CPUfreq table support for creating a table
of frequencies from the OPP layer. Ensure that it's build to avoid
link-time errors.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[khilman@ti.com: make user-selectable, but default y]
Signed-off-by: Kevin Hilman <khilman@ti.com>
a125a17fa61afe2fa4e52b239dd20af8ce90c9f7 07-Jan-2012 Jaecheol Lee <jc.lee@samsung.com> [CPUFREQ] EXYNOS: Make EXYNOS common cpufreq driver

To support various EXYNOS series SoCs commonly,
added exynos common structure.
exynos-cpufreq.c => EXYNOS series common cpufreq driver
exynos4210-cpufreq.c => EXYNOS4210 support cpufreq driver

Signed-off-by: Jaecheol Lee <jc.lee@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
731e0cc639364646d36981d90ab0b6af12b8face 12-Aug-2010 Santosh Shilimkar <santosh.shilimkar@ti.com> cpufreq: OMAP: cleanup for multi-SoC support, move into drivers/cpufreq

Move OMAP cpufreq driver from arch/arm/mach-omap2 into
drivers/cpufreq, along with a few cleanups:

- generalize support for better handling of different SoCs in the OMAP
- use OPP layer instead of OMAP clock internals for frequency table init

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[khilman@ti.com: move to drivers]
Signed-off-by: Kevin Hilman <khilman@ti.com>
5d8c665889e27e1b8989ca465166e8897dc302d1 29-Jun-2011 Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> powerpc/cpufreq: Add cpufreq driver for Momentum Maple boards

Add simple cpufreq driver for Maple-based boards (ppc970fx evaluation
kit and others). Driver is based on a cpufreq driver for 64-bit powermac
boxes with all pmac-dependant features removed and simple cleanup
applied.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
15964d388528c1dbb672027c8003fe7e81630a35 07-Jun-2011 Kukjin Kim <kgene.kim@samsung.com> [CPUFREQ] Move compile for S3C64XX cpufreq to /drivers/cpufreq

Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
069283c3ec87e0abaa14f6bef96342b609f0fb92 07-Jun-2011 Dave Jones <davej@kernel.org> [CPUFREQ] Remove some vi noise that escaped into the Makefile.
f7d770790f29781116d0de1339214934b8020c1e 01-Jun-2011 Kukjin Kim <kgene.kim@samsung.com> [CPUFREQ] Move ARM Samsung cpufreq drivers to drivers/cpufreq/

According to discussion of the ARM arch subsystem migration,
ARM cpufreq drivers move to drivers/cpufreq. So this patch
adds Kconfig.arm for ARM like x86 and adds Samsung S5PV210
and EXYNOS4210 cpufreq driver compile in there.
As a note, otherw will be moved.

Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Dave Jones <davej@redhat.com>
be2de99beaca6506a1f97a636750c108a41b5c00 10-May-2011 Mark Brown <broonie@opensource.wolfsonmicro.com> [CPUFREQ/S3C64xx] Move S3C64xx CPUfreq driver into drivers/cpufreq

This is a straight code motion patch, there are no changes to the driver
itself. The Kconfig is left untouched as the ARM CPUfreq Kconfig is all
in one big block in arm/Kconfig and should be moved en masse rather than
being done piecemeal.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Dave Jones <davej@redhat.com>
f0e733f32e56ded9309a8b8da3a77d47beb3cbdd 15-May-2011 Linus Walleij <linus.walleij@linaro.org> cpufreq: make DB8500 cpufreq driver compile

Concluding interface update and movement of the driver by making
the DB8500 cpufreq driver compile in the cpufreq subsystem.

Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
bb0a56ecc4ba2a3db1b6ea6949c309886e3447d3 20-May-2011 Dave Jones <davej@redhat.com> [CPUFREQ] Move x86 drivers to drivers/cpufreq/

Signed-off-by: Dave Jones <davej@redhat.com>
b9170836d1aa4ded7cc1ac1cb8fbc7867061c98c 01-Jun-2005 Dave Jones <davej@redhat.com> [CPUFREQ] Conservative cpufreq governer

A new cpufreq module, based on the ondemand one with my additional patches
just posted. This one is more suitable for battery environments where its
probably more appealing to have the cpu freq gracefully increase and decrease
rather than flip between the min and max freq's.

N.B. Bruno Ducrot pointed out that the amd64's "do have unacceptable latency
between min and max freq transition, due to the step-by-step requirements
(200MHz IIRC)"; so AMD64 users would probably benefit from this too.

Signed-off-by: Alexander Clouter <alex-kernel@digriz.org.uk>
Signed-off-by: Dave Jones <davej@redhat.com>
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 17-Apr-2005 Linus Torvalds <torvalds@ppc970.osdl.org> Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!