Commit Graph

83 Commits

Author SHA1 Message Date
Huacai Chen
ccf5145414 cpufreq: Add Loongson-3 CPUFreq driver support
Some of LoongArch processors (Loongson-3 series) support DVFS, their
IOCSR.FEATURES has IOCSRF_FREQSCALE set. And they has a micro-core in
the package called SMC (System Management Controller), which can be
used to detect temperature, control fans, scale frequency and voltage,
etc.

The Loongson-3 CPUFreq driver is very simple now, it communicate with
SMC, get DVFS info, set target frequency from CPUFreq core, and so on.

There is a command list to interact with SMC, widely-used commands in
the CPUFreq driver include:

CMD_GET_VERSION: Get SMC firmware version.

CMD_GET_FEATURE: Get enabled SMC features.

CMD_SET_FEATURE: Enable SMC features, such as basic DVFS, BOOST.

CMD_GET_FREQ_LEVEL_NUM: Get the number of all frequency levels.

CMD_GET_FREQ_BOOST_LEVEL: Get the first boost frequency level.

CMD_GET_FREQ_LEVEL_INFO: Get the detail info of a frequency level.

CMD_GET_FREQ_INFO: Get the current frequency.

CMD_SET_FREQ_INFO: Set the target frequency.

In future we will add automatic frequency scaling, which is similar to
Intel's HWP (HardWare P-State).

Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
[ Viresh: Minor formatting cleanups, change return type of exit() to
	  void and use devm_mutex_init() ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2024-07-09 08:45:43 +05:30
Sunil V L
7ee1378736
cpufreq: Move CPPC configs to common Kconfig and add RISC-V
CPPC related config options are currently defined only in ARM specific
file. However, they are required for RISC-V as well. Instead of creating
a new Kconfig.riscv file and duplicating them, move them to the common
Kconfig file and enable RISC-V too.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20240208034414.22579-3-sunilvl@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-03-19 18:30:55 -07:00
Ard Biesheuvel
cf8e865810 arch: Remove Itanium (IA-64) architecture
The Itanium architecture is obsolete, and an informal survey [0] reveals
that any residual use of Itanium hardware in production is mostly HP-UX
or OpenVMS based. The use of Linux on Itanium appears to be limited to
enthusiasts that occasionally boot a fresh Linux kernel to see whether
things are still working as intended, and perhaps to churn out some
distro packages that are rarely used in practice.

None of the original companies behind Itanium still produce or support
any hardware or software for the architecture, and it is listed as
'Orphaned' in the MAINTAINERS file, as apparently, none of the engineers
that contributed on behalf of those companies (nor anyone else, for that
matter) have been willing to support or maintain the architecture
upstream or even be responsible for applying the odd fix. The Intel
firmware team removed all IA-64 support from the Tianocore/EDK2
reference implementation of EFI in 2018. (Itanium is the original
architecture for which EFI was developed, and the way Linux supports it
deviates significantly from other architectures.) Some distros, such as
Debian and Gentoo, still maintain [unofficial] ia64 ports, but many have
dropped support years ago.

While the argument is being made [1] that there is a 'for the common
good' angle to being able to build and run existing projects such as the
Grid Community Toolkit [2] on Itanium for interoperability testing, the
fact remains that none of those projects are known to be deployed on
Linux/ia64, and very few people actually have access to such a system in
the first place. Even if there were ways imaginable in which Linux/ia64
could be put to good use today, what matters is whether anyone is
actually doing that, and this does not appear to be the case.

There are no emulators widely available, and so boot testing Itanium is
generally infeasible for ordinary contributors. GCC still supports IA-64
but its compile farm [3] no longer has any IA-64 machines. GLIBC would
like to get rid of IA-64 [4] too because it would permit some overdue
code cleanups. In summary, the benefits to the ecosystem of having IA-64
be part of it are mostly theoretical, whereas the maintenance overhead
of keeping it supported is real.

So let's rip off the band aid, and remove the IA-64 arch code entirely.
This follows the timeline proposed by the Debian/ia64 maintainer [5],
which removes support in a controlled manner, leaving IA-64 in a known
good state in the most recent LTS release. Other projects will follow
once the kernel support is removed.

[0] https://lore.kernel.org/all/CAMj1kXFCMh_578jniKpUtx_j8ByHnt=s7S+yQ+vGbKt9ud7+kQ@mail.gmail.com/
[1] https://lore.kernel.org/all/0075883c-7c51-00f5-2c2d-5119c1820410@web.de/
[2] https://gridcf.org/gct-docs/latest/index.html
[3] https://cfarm.tetaneutral.net/machines/list/
[4] https://lore.kernel.org/all/87bkiilpc4.fsf@mid.deneb.enyo.de/
[5] https://lore.kernel.org/all/ff58a3e76e5102c94bb5946d99187b358def688a.camel@physik.fu-berlin.de/

Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-09-11 08:13:17 +00:00
Viresh Kumar
0b76cc3e90 cpufreq: Make CONFIG_CPUFREQ_DT_PLATDEV depend on OF
The cpufreq-dt-platform.c driver requires CONFIG_OF to be selected. Mark
it as a dependency.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202306250025.savpMM8L-lkp@intel.com/
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-06-30 09:43:43 +02:00
Rafael J. Wysocki
813ce98178 ARM cpufreq updates for 6.5
- Add support to build cpufreq-dt-platdev as module (Zhipeng Wang).
 
 - Don't allocate Sparc's cpufreq_driver dynamically (Viresh Kumar).
 
 - Add support for TI's AM62A7 platform (Vibhore Vardhan).
 
 - Add support for Armada's ap807 platform (Russell King (Oracle)).
 
 - Add support for StarFive JH7110 SoC (Mason Huo).
 
 - Fix voltage selection for Mediatek Socs (Daniel Golle).
 
 - Fix error handling in Tegra's cpufreq driver (Christophe JAILLET).
 
 - Document Qualcomm's IPQ8074 in DT bindings (Robert Marko).
 
 - Don't warn for disabling a non-existing frequency for imx6q cpufreq
   driver (Christoph Niedermaier).
 
 - Use dev_err_probe() in Qualcomm's cpufreq driver (Andrew Halaney).
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Merge tag 'cpufreq-arm-updates-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm

Pull ARM cpufreq updates for 6.5 from Viresh Kumar:

"- Add support to build cpufreq-dt-platdev as module (Zhipeng Wang).

 - Don't allocate Sparc's cpufreq_driver dynamically (Viresh Kumar).

 - Add support for TI's AM62A7 platform (Vibhore Vardhan).

 - Add support for Armada's ap807 platform (Russell King (Oracle)).

 - Add support for StarFive JH7110 SoC (Mason Huo).

 - Fix voltage selection for Mediatek Socs (Daniel Golle).

 - Fix error handling in Tegra's cpufreq driver (Christophe JAILLET).

 - Document Qualcomm's IPQ8074 in DT bindings (Robert Marko).

 - Don't warn for disabling a non-existing frequency for imx6q cpufreq
   driver (Christoph Niedermaier).

 - Use dev_err_probe() in Qualcomm's cpufreq driver (Andrew Halaney)."
2023-06-27 20:10:57 +02:00
Mario Limonciello
a4ba10bf68 cpufreq: amd-pstate: Set default governor to schedutil
The Kconfig currently defaults the governor to schedutil on x86_64
only when intel-pstate and SMP have been selected.

If the kernel is built only with amd-pstate, the default governor
should also be schedutil.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Leo Li <sunpeng.li@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Tested-by: Perry Yuan <Perry.Yuan@amd.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-06-20 12:18:08 +02:00
Zhipeng Wang
3b062a0869 cpufreq: dt-platdev: Support building as module
Make the cpufreq platdev driver as tristate so that it can be built
as loadable module.

Also add MODULE_LICENSE to support building as module.

Signed-off-by: Zhipeng Wang <zhipeng.wang_1@nxp.com>
[ Viresh: Merged two commits, included module.h ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2023-06-05 16:33:05 +05:30
Linus Torvalds
2504ba8b01 Power management updates for 6.3-rc1
- Add EPP support to the AMD P-state cpufreq driver (Perry Yuan, Wyes
    Karny, Arnd Bergmann, Bagas Sanjaya).
 
  - Drop the custom cpufreq driver for loongson1 that is not necessary
    any more and the corresponding cpufreq platform device (Keguang
    Zhang).
 
  - Remove "select SRCU" from system sleep, cpufreq and OPP Kconfig
    entries (Paul E. McKenney).
 
  - Enable thermal cooling for Tegra194 (Yi-Wei Wang).
 
  - Register module device table and add missing compatibles for
    cpufreq-qcom-hw (Nícolas F. R. A. Prado, Abel Vesa and Luca Weiss).
 
  - Various dt binding updates for qcom-cpufreq-nvmem and opp-v2-kryo-cpu
    (Christian Marangi).
 
  - Make kobj_type structure in the cpufreq core constant (Thomas
    Weißschuh).
 
  - Make cpufreq_unregister_driver() return void (Uwe Kleine-König).
 
  - Make the TEO cpuidle governor check CPU utilization in order to refine
   idle state selection (Kajetan Puchalski).
 
  - Make Kconfig select the haltpoll cpuidle governor when the haltpoll
    cpuidle driver is selected and replace a default_idle() call in that
    driver with arch_cpu_idle() to allow MWAIT to be used (Li RongQing).
 
  - Add Emerald Rapids Xeon support to the intel_idle driver (Artem
    Bityutskiy).
 
  - Add ARCH_SUSPEND_POSSIBLE dependencies for ARMv4 cpuidle drivers to
    avoid randconfig build failures (Arnd Bergmann).
 
  - Make kobj_type structures used in the cpuidle sysfs interface
    constant (Thomas Weißschuh).
 
  - Make the cpuidle driver registration code update microsecond values
    of idle state parameters in accordance with their nanosecond values
    if they are provided (Rafael Wysocki).
 
  - Make the PSCI cpuidle driver prevent topology CPUs from being
    suspended on PREEMPT_RT (Krzysztof Kozlowski).
 
  - Document that pm_runtime_force_suspend() cannot be used with
    DPM_FLAG_SMART_SUSPEND (Richard Fitzgerald).
 
  - Add EXPORT macros for exporting PM functions from drivers (Richard
    Fitzgerald).
 
  - Remove /** from non-kernel-doc comments in hibernation code (Randy
    Dunlap).
 
  - Fix possible name leak in powercap_register_zone() (Yang Yingliang).
 
  - Add Meteor Lake and Emerald Rapids support to the intel_rapl power
    capping driver (Zhang Rui).
 
  - Modify the idle_inject power capping facility to support 100% idle
    injection (Srinivas Pandruvada).
 
  - Fix large time windows handling in the intel_rapl power capping
    driver (Zhang Rui).
 
  - Fix memory leaks with using debugfs_lookup() in the generic PM
    domains and Energy Model code (Greg Kroah-Hartman).
 
  - Add missing 'cache-unified' property in the example for kryo OPP
    bindings (Rob Herring).
 
  - Fix error checking in opp_migrate_dentry() (Qi Zheng).
 
  - Let qcom,opp-fuse-level be a 2-long array for qcom SoCs (Konrad
    Dybcio).
 
  - Modify some power management utilities to use the canonical ftrace
    path (Ross Zwisler).
 
  - Correct spelling problems for Documentation/power/ as reported by
    codespell (Randy Dunlap).
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Merge tag 'pm-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These add EPP support to the AMD P-state cpufreq driver, add support
  for new platforms to the Intel RAPL power capping driver, intel_idle
  and the Qualcomm cpufreq driver, enable thermal cooling for Tegra194,
  drop the custom cpufreq driver for loongson1 that is not necessary any
  more (and the corresponding cpufreq platform device), fix assorted
  issues and clean up code.

  Specifics:

   - Add EPP support to the AMD P-state cpufreq driver (Perry Yuan, Wyes
     Karny, Arnd Bergmann, Bagas Sanjaya)

   - Drop the custom cpufreq driver for loongson1 that is not necessary
     any more and the corresponding cpufreq platform device (Keguang
     Zhang)

   - Remove "select SRCU" from system sleep, cpufreq and OPP Kconfig
     entries (Paul E. McKenney)

   - Enable thermal cooling for Tegra194 (Yi-Wei Wang)

   - Register module device table and add missing compatibles for
     cpufreq-qcom-hw (Nícolas F. R. A. Prado, Abel Vesa and Luca Weiss)

   - Various dt binding updates for qcom-cpufreq-nvmem and
     opp-v2-kryo-cpu (Christian Marangi)

   - Make kobj_type structure in the cpufreq core constant (Thomas
     Weißschuh)

   - Make cpufreq_unregister_driver() return void (Uwe Kleine-König)

   - Make the TEO cpuidle governor check CPU utilization in order to
     refine idle state selection (Kajetan Puchalski)

   - Make Kconfig select the haltpoll cpuidle governor when the haltpoll
     cpuidle driver is selected and replace a default_idle() call in
     that driver with arch_cpu_idle() to allow MWAIT to be used (Li
     RongQing)

   - Add Emerald Rapids Xeon support to the intel_idle driver (Artem
     Bityutskiy)

   - Add ARCH_SUSPEND_POSSIBLE dependencies for ARMv4 cpuidle drivers to
     avoid randconfig build failures (Arnd Bergmann)

   - Make kobj_type structures used in the cpuidle sysfs interface
     constant (Thomas Weißschuh)

   - Make the cpuidle driver registration code update microsecond values
     of idle state parameters in accordance with their nanosecond values
     if they are provided (Rafael Wysocki)

   - Make the PSCI cpuidle driver prevent topology CPUs from being
     suspended on PREEMPT_RT (Krzysztof Kozlowski)

   - Document that pm_runtime_force_suspend() cannot be used with
     DPM_FLAG_SMART_SUSPEND (Richard Fitzgerald)

   - Add EXPORT macros for exporting PM functions from drivers (Richard
     Fitzgerald)

   - Remove /** from non-kernel-doc comments in hibernation code (Randy
     Dunlap)

   - Fix possible name leak in powercap_register_zone() (Yang Yingliang)

   - Add Meteor Lake and Emerald Rapids support to the intel_rapl power
     capping driver (Zhang Rui)

   - Modify the idle_inject power capping facility to support 100% idle
     injection (Srinivas Pandruvada)

   - Fix large time windows handling in the intel_rapl power capping
     driver (Zhang Rui)

   - Fix memory leaks with using debugfs_lookup() in the generic PM
     domains and Energy Model code (Greg Kroah-Hartman)

   - Add missing 'cache-unified' property in the example for kryo OPP
     bindings (Rob Herring)

   - Fix error checking in opp_migrate_dentry() (Qi Zheng)

   - Let qcom,opp-fuse-level be a 2-long array for qcom SoCs (Konrad
     Dybcio)

   - Modify some power management utilities to use the canonical ftrace
     path (Ross Zwisler)

   - Correct spelling problems for Documentation/power/ as reported by
     codespell (Randy Dunlap)"

* tag 'pm-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (53 commits)
  Documentation: amd-pstate: disambiguate user space sections
  cpufreq: amd-pstate: Fix invalid write to MSR_AMD_CPPC_REQ
  dt-bindings: opp: opp-v2-kryo-cpu: enlarge opp-supported-hw maximum
  dt-bindings: cpufreq: qcom-cpufreq-nvmem: make cpr bindings optional
  dt-bindings: cpufreq: qcom-cpufreq-nvmem: specify supported opp tables
  PM: Add EXPORT macros for exporting PM functions
  cpuidle: psci: Do not suspend topology CPUs on PREEMPT_RT
  MIPS: loongson32: Drop obsolete cpufreq platform device
  powercap: intel_rapl: Fix handling for large time window
  cpuidle: driver: Update microsecond values of state parameters as needed
  cpuidle: sysfs: make kobj_type structures constant
  cpuidle: add ARCH_SUSPEND_POSSIBLE dependencies
  PM: EM: fix memory leak with using debugfs_lookup()
  PM: domains: fix memory leak with using debugfs_lookup()
  cpufreq: Make kobj_type structure constant
  cpufreq: davinci: Fix clk use after free
  cpufreq: amd-pstate: avoid uninitialized variable use
  cpufreq: Make cpufreq_unregister_driver() return void
  OPP: fix error checking in opp_migrate_dentry()
  dt-bindings: cpufreq: cpufreq-qcom-hw: Add SM8550 compatible
  ...
2023-02-21 12:13:58 -08:00
Paul E. McKenney
38a29e5834 drivers/cpufreq: Remove "select SRCU"
Now that the SRCU Kconfig option is unconditionally selected, there is
no longer any point in selecting it.  Therefore, remove the "select SRCU"
Kconfig statements.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-01-20 17:51:25 +01:00
Keguang Zhang
9a55ab6f02 cpufreq: loongson1: Delete obsolete driver
The generic DT based cpufreq driver works for Loongson-1,
so delete the old custom driver.

Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-01-20 17:47:14 +01:00
Arnd Bergmann
349619f064 cpufreq: remove sa1100 driver
The sa11xx platform has two cpufreq drivers, one for the older
StrongARM1100 SoC, and a second one for StrongARM1110. After
the removal of most SA1100 based machines, this driver is unused,
and only the sa1110-cpufreq driver remains.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-01-16 09:26:05 +01:00
Randy Dunlap
9d822ccf33 cpufreq: loongson2: fix Kconfig "its" grammar
Use the possessive "its" instead of the contraction "it's"
where appropriate.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-25 20:34:56 +02:00
Alexander Monakov
733dda9cc8 cpufreq: Kconfig: fix documentation links
User documentation for cpufreq governors and drivers has been moved to
admin-guide; adjust references from Kconfig entries accordingly.

Remove references from undocumented cpufreq drivers, as well as the
'userspace' cpufreq governor, for which no additional details are
provided in the admin-guide text.

Fixes: 2a0e492798 ("cpufreq: User/admin documentation update and consolidation")
Signed-off-by: Alexander Monakov <amonakov@ispras.ru>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-21 19:00:42 +02:00
Rafael J. Wysocki
db865272d9 cpufreq: Avoid configuring old governors as default with intel_pstate
Commit 33aa46f252 ("cpufreq: intel_pstate: Use passive mode by
default without HWP") was meant to cause intel_pstate to be used
in the passive mode with the schedutil governor on top of it, but
it missed the case in which either "ondemand" or "conservative"
was selected as the default governor in the existing kernel config,
in which case the previous old governor configuration would be used,
causing the default legacy governor to be used on top of intel_pstate
instead of schedutil.

Address this by preventing "ondemand" and "conservative" from being
configured as the default cpufreq governor in the case when schedutil
is the default choice for the default governor setting.

[Note that the default cpufreq governor can still be set via the
 kernel command line if need be and that choice is not limited,
 so if anyone really wants to use one of the legacy governors by
 default, it can be achieved this way.]

Fixes: 33aa46f252 ("cpufreq: intel_pstate: Use passive mode by default without HWP")
Reported-by: Julia Lawall <julia.lawall@inria.fr>
Cc: 5.8+ <stable@vger.kernel.org> # 5.8+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-10-27 18:45:34 +01:00
Valentin Schneider
f259eab3ea cpufreq: make schedutil the default for arm and arm64
schedutil is already a hard-requirement for EAS, which has lead to making
it default on arm (when CONFIG_BIG_LITTLE), see:

  commit 8fdcca8e25 ("cpufreq: Select schedutil when using big.LITTLE")

One thing worth pointing out is that schedutil isn't only relevant for
asymmetric CPU capacity systems; for instance, schedutil is the only
governor that honours util-clamp performance requests. Another good example
of this is x86 switching to using it by default in:

  commit a00ec3874e ("cpufreq: intel_pstate: Select schedutil as the default governor")

Arguably it should be made the default for all architectures, but it seems
better to wait for them to also gain frequency invariance powers. Make it
the default for arm && arm64 for now.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-07-30 11:40:29 +05:30
Geert Uytterhoeven
1f1755af4f cpufreq: qoriq: Add platform dependencies
The Freescale QorIQ clock controller is only present on Freescale E500MC
and Layerscape SoCs.  Add platform dependencies to the QORIQ_CPUFREQ
config symbol, to avoid asking the user about it when configuring a
kernel without E500MC or Layerscape support.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-05-08 10:53:10 +05:30
Linus Walleij
8fdcca8e25 cpufreq: Select schedutil when using big.LITTLE
When we are using a system with big.LITTLE HMP
configuration, we need to use EAS to schedule the
system.

As can be seen from kernel/sched/topology.c:

 "EAS can be used on a root domain if it meets all the following conditions:
  1. an Energy Model (EM) is available;
  2. the SD_ASYM_CPUCAPACITY flag is set in the sched_domain hierarchy.
  3. no SMT is detected.
  4. the EM complexity is low enough to keep scheduling overheads low;
  5. schedutil is driving the frequency of all CPUs of the rd;"

This means that at the very least, schedutil needs to be
available as a scheduling policy for EAS to work on these
systems. Make this explicit by defaulting to the schedutil
governor if BIG_LITTLE is selected.

Currently users of the TC2 board (like me) has to figure these
dependencies out themselves and it is not helpful.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-03 11:20:06 +02:00
Rafael J. Wysocki
a00ec3874e cpufreq: intel_pstate: Select schedutil as the default governor
Modify cpufreq Kconfig to select schedutil as the default governor
if the intel_pstate driver has been selected and SMP support is
enabled (because schedutil depends on SMP).

Also select schedutil as well as the performance governor from the
intel_pstate Kconfig section to ensure the equivalence of the passive
and active mode governor configuration options.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-26 20:32:49 +01:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Yue Hu
9df1e2c60d cpufreq: boost: Remove CONFIG_CPU_FREQ_BOOST_SW Kconfig option
Commit 2fb4719b25 ("cpufreq / boost: Kconfig: Support for
software-managed BOOST") added the CONFIG_CPU_FREQ_BOOST_SW config.
However EXYNOS based cpufreq drivers have been removed because of
switching to cpufreq-dt driver which will set boost-attr if required.

So, let's remove this option and update cpufreq_generic_attr[].

Signed-off-by: Yue Hu <huyue2@yulong.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-10 10:00:50 +02:00
Amit Kucheria
afa1f2ab43 thermal: cpu_cooling: Require thermal core to be compiled in
The CPU cooling driver (cpu_cooling.c) allows the platform's cpufreq
driver to register as a cooling device and cool down the platform by
throttling the CPU frequency. In order to be able to auto-register a
cpufreq driver as a cooling device from the cpufreq core, we need access
to code inside cpu_cooling.c which, in turn, accesses code inside
thermal core.

CPU_FREQ is a bool while THERMAL is tristate.  In some configurations
(e.g. allmodconfig), CONFIG_THERMAL ends up as a module while
CONFIG_CPU_FREQ is compiled in. This leads to following error:

drivers/cpufreq/cpufreq.o: In function `cpufreq_offline':
cpufreq.c:(.text+0x407c): undefined reference to `cpufreq_cooling_unregister'
drivers/cpufreq/cpufreq.o: In function `cpufreq_online':
cpufreq.c:(.text+0x70c0): undefined reference to `of_cpufreq_cooling_register'

Given that platforms using CPU_THERMAL usually want it compiled-in so it
is available early in boot, make CPU_THERMAL depend on THERMAL being
compiled-in instead of allowing it to be a module.

As a result of this change, get rid of the ugly (!CPU_THERMAL ||
THERMAL) dependency in all cpufreq drivers using CPU_THERMAL.

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-29 11:46:31 +01:00
Corentin LABBE
3d70671667 cpufreq: remove at32ap-cpufreq
Since AVR32 arch was removed, at32ap-cpufreq is useless.
Remove this driver.

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-02-07 11:44:23 +01:00
James Hogan
0d307935fe cpufreq: Add Loongson machine dependencies
The MIPS loongson cpufreq drivers don't build unless configured for the
correct machine type, due to dependency on machine specific architecture
headers and symbols in machine specific platform code.

More specifically loongson1-cpufreq.c uses RST_CPU_EN and RST_CPU,
neither of which is defined in asm/mach-loongson32/regs-clk.h unless
CONFIG_LOONGSON1_LS1B=y, and loongson2_cpufreq.c references
loongson2_clockmod_table[], which is only defined in
arch/mips/loongson64/lemote-2f/clock.c, i.e. when
CONFIG_LEMOTE_MACH2F=y.

Add these dependencies to Kconfig to avoid randconfig / allyesconfig
build failures (e.g. when based on BMIPS which also has a cpufreq
driver).

Signed-off-by: James Hogan <jhogan@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-11-21 23:58:54 +01:00
Tang Yuantian
5026ac2314 cpufreq: qoriq: add ARM64 SoCs support
Add ARM64 config to Kconfig to enable CPU frequency feature on
NXP ARM64 SoCs.

Signed-off-by: Tang Yuantian <yuantian.tang@nxp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-09 14:33:01 +01:00
Markus Mayer
cdb56cbfd7 cpufreq: bmips-cpufreq: CPUfreq driver for Broadcom's BMIPS SoCs
Add the MIPS CPUfreq driver. This driver currently supports CPUfreq on
BMIPS5xxx-based SoCs.

Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-09 01:22:44 +01:00
Viresh Kumar
801e0f378f cpufreq: Remove CONFIG_CPU_FREQ_STAT_DETAILS config option
This doesn't have any benefit apart from saving a small amount of memory
when it is disabled. The ifdef hackery in the code makes it dirty
unnecessarily.

Clean it up by removing the Kconfig option completely. Few defconfigs
are also updated and CONFIG_CPU_FREQ_STAT_DETAILS is replaced with
CONFIG_CPU_FREQ_STAT now in them, as users wanted stats to be enabled.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-03 23:59:39 +01:00
Rafael J. Wysocki
b6e2511782 Merge branch 'pm-cpufreq-sched' into pm-cpufreq 2016-10-02 01:42:33 +02:00
Viresh Kumar
33cc4fc1b2 cpufreq: dt: Update kconfig description
The cpufreq DT driver also supports systems that have multiple
clock/voltage domains for CPUs, i.e. multiple policy systems.

The description of the Kconfig entry was never updated after the driver
was modified to support such systems, fix it.

Reported-by: Juri Lelli <Juri.Lelli@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13 02:39:12 +02:00
Rafael J. Wysocki
58919e83c8 cpufreq / sched: Pass flags to cpufreq_update_util()
It is useful to know the reason why cpufreq_update_util() has just
been called and that can be passed as flags to cpufreq_update_util()
and to the ->func() callback in struct update_util_data.  However,
doing that in addition to passing the util and max arguments they
already take would be clumsy, so avoid it.

Instead, use the observation that the schedutil governor is part
of the scheduler proper, so it can access scheduler data directly.
This allows the util and max arguments of cpufreq_update_util()
and the ->func() callback in struct update_util_data to be replaced
with a flags one, but schedutil has to be modified to follow.

Thus make the schedutil governor obtain the CFS utilization
information from the scheduler and use the "RT" and "DL" flags
instead of the special utilization value of ULONG_MAX to track
updates from the RT and DL sched classes.  Make it non-modular
too to avoid having to export scheduler variables to modules at
large.

Next, update all of the other users of cpufreq_update_util()
and the ->func() callback in struct update_util_data accordingly.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-08-16 22:14:55 +02:00
Borislav Petkov
79ad70de53 cpufreq: Do not default-yes CPU_FREQ_STAT
CPU frequency transition statistics are not absolutely required for
proper cpufreq operation on the system AFAICT so remove the default-yes
setting in Kconfig.

Signed-off-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>
2016-08-03 01:34:11 +02:00
Rafael J. Wysocki
1aefc75b24 cpufreq: stats: Make the stats code non-modular
The modularity of cpufreq_stats is quite problematic.

First off, the usage of policy notifiers for the initialization
and cleanup in the cpufreq_stats module is inherently racy with
respect to CPU offline/online and the initialization and cleanup
of the cpufreq driver.

Second, fast frequency switching (used by the schedutil governor)
cannot be enabled if any transition notifiers are registered, so
if the cpufreq_stats module (that registers a transition notifier
for updating transition statistics) is loaded, the schedutil governor
cannot use fast frequency switching.

On the other hand, allowing cpufreq_stats to be built as a module
doesn't really add much value.  Arguably, there's not much reason
for that code to be modular at all.

For the above reasons, make the cpufreq stats code non-modular,
modify the core to invoke functions provided by that code directly
and drop the notifiers from it.

Make the stats sysfs attributes appear empty if fast frequency
switching is enabled as the statistics will not be updated in that
case anyway (and returning -EBUSY from those attributes breaks
powertop).

While at it, clean up Kconfig help for the CPU_FREQ_STAT and
CPU_FREQ_STAT_DETAILS options.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-06-02 23:24:41 +02:00
Rafael J. Wysocki
c29af6f1a4 Merge branch 'pm-cpufreq-sched' into pm-cpufreq 2016-05-11 22:48:20 +02:00
Arnd Bergmann
cfe9492fdf cpufreq: schedutil: Make default depend on CONFIG_SMP
CPU_FREQ_GOV_SCHEDUTIL gained a dependency on SMP, so now we
get a warning if it gets selected by CPU_FREQ_DEFAULT_GOV_SCHEDUTIL
without SMP:

warning: (CPU_FREQ_DEFAULT_GOV_SCHEDUTIL) selects CPU_FREQ_GOV_SCHEDUTIL which has unmet direct dependencies (CPU_FREQ && SMP)

This adds another dependency to avoid the problem.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: bf7cdff194 (cpufreq: schedutil: Make it depend on CONFIG_SMP)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-11 22:47:44 +02:00
Rafael J. Wysocki
d87de8f38a Merge branch 'pm-cpufreq-sched' into pm-cpufreq 2016-05-09 16:00:10 +02:00
Rafael J. Wysocki
bf7cdff194 cpufreq: schedutil: Make it depend on CONFIG_SMP
Make the schedutil cpufreq governor depend on CONFIG_SMP, because
the scheduler-provided utilization numbers used by it are only
available with CONFIG_SMP set.

Fixes: 9bdcb44e39 (cpufreq: schedutil: New governor based on scheduler utilization data)
Reported-by: Steve Muckle <steve.muckle@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-06 22:33:33 +02:00
Viresh Kumar
f56aad1d98 cpufreq: dt: Add generic platform-device creation support
Multiple platforms are using the generic cpufreq-dt driver now, and all
of them are required to create a platform device with name "cpufreq-dt",
in order to get the cpufreq-dt probed.

Many of them do it from platform code, others have special drivers just
to do that.

It would be more sensible to do this at a generic place, where all such
platform can mark their entries.

This patch adds a separate file to get this device created. Currently
the compat list of platforms that we support is empty, and will be
filled in as and when we move platforms to use it.

It always compiles as part of the kernel and so doesn't need a
module-exit operation.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-09 01:18:42 +02:00
Rafael J. Wysocki
9bdcb44e39 cpufreq: schedutil: New governor based on scheduler utilization data
Add a new cpufreq scaling governor, called "schedutil", that uses
scheduler-provided CPU utilization information as input for making
its decisions.

Doing that is possible after commit 34e2c555f3 (cpufreq: Add
mechanism for registering utilization update callbacks) that
introduced cpufreq_update_util() called by the scheduler on
utilization changes (from CFS) and RT/DL task status updates.
In particular, CPU frequency scaling decisions may be based on
the the utilization data passed to cpufreq_update_util() by CFS.

The new governor is relatively simple.

The frequency selection formula used by it depends on whether or not
the utilization is frequency-invariant.  In the frequency-invariant
case the new CPU frequency is given by

	next_freq = 1.25 * max_freq * util / max

where util and max are the last two arguments of cpufreq_update_util().
In turn, if util is not frequency-invariant, the maximum frequency in
the above formula is replaced with the current frequency of the CPU:

	next_freq = 1.25 * curr_freq * util / max

The coefficient 1.25 corresponds to the frequency tipping point at
(util / max) = 0.8.

All of the computations are carried out in the utilization update
handlers provided by the new governor.  One of those handlers is
used for cpufreq policies shared between multiple CPUs and the other
one is for policies with one CPU only (and therefore it doesn't need
to use any extra synchronization means).

The governor supports fast frequency switching if that is supported
by the cpufreq driver in use and possible for the given policy.
In the fast switching case, all operations of the governor take
place in its utilization update handlers.  If fast switching cannot
be used, the frequency switch operations are carried out with the
help of a work item which only calls __cpufreq_driver_target()
(under a mutex) to trigger a frequency update (to a value already
computed beforehand in one of the utilization update handlers).

Currently, the governor treats all of the RT and DL tasks as
"unknown utilization" and sets the frequency to the allowed
maximum when updated from the RT or DL sched classes.  That
heavy-handed approach should be replaced with something more
subtle and specifically targeted at RT and DL tasks.

The governor shares some tunables management code with the
"ondemand" and "conservative" governors and uses some common
definitions from cpufreq_governor.h, but apart from that it
is stand-alone.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-04-02 01:09:12 +02:00
Rafael J. Wysocki
2d0c58ad60 cpufreq: governor: Move abstract gov_attr_set code to seperate file
Move abstract code related to struct gov_attr_set to a separate (new)
file so it can be shared with (future) goverernors that won't share
more code with "ondemand" and "conservative".

No intentional functional changes.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-04-02 01:09:01 +02:00
Rafael J. Wysocki
4ed3900427 Merge branch 'pm-cpufreq'
* pm-cpufreq: (94 commits)
  intel_pstate: Do not skip samples partially
  intel_pstate: Remove freq calculation from intel_pstate_calc_busy()
  intel_pstate: Move intel_pstate_calc_busy() into get_target_pstate_use_performance()
  intel_pstate: Optimize calculation for max/min_perf_adj
  intel_pstate: Remove extra conversions in pid calculation
  cpufreq: Move scheduler-related code to the sched directory
  Revert "cpufreq: postfix policy directory with the first CPU in related_cpus"
  cpufreq: Reduce cpufreq_update_util() overhead a bit
  cpufreq: Select IRQ_WORK if CPU_FREQ_GOV_COMMON is set
  cpufreq: Remove 'policy->governor_enabled'
  cpufreq: Rename __cpufreq_governor() to cpufreq_governor()
  cpufreq: Relocate handle_update() to kill its declaration
  cpufreq: governor: Drop unnecessary checks from show() and store()
  cpufreq: governor: Fix race in dbs_update_util_handler()
  cpufreq: governor: Make gov_set_update_util() static
  cpufreq: governor: Narrow down the dbs_data_mutex coverage
  cpufreq: governor: Make dbs_data_mutex static
  cpufreq: governor: Relocate definitions of tuners structures
  cpufreq: governor: Move per-CPU data to the common code
  cpufreq: governor: Make governor private data per-policy
  ...
2016-03-14 14:22:03 +01:00
Rafael J. Wysocki
e6f036571e cpufreq: Select IRQ_WORK if CPU_FREQ_GOV_COMMON is set
Commit 0eb463be3436 (cpufreq: governor: Replace timers with utilization
update callbacks) made CPU_FREQ select IRQ_WORK, but that's not
necessary, as it is sufficient for IRQ_WORK to be selected by
CPU_FREQ_GOV_COMMON, so modify the cpufreq Kconfig to that effect.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2016-03-09 15:01:37 +01:00
Rafael J. Wysocki
9be4fd2c77 cpufreq: governor: Replace timers with utilization update callbacks
Instead of using a per-CPU deferrable timer for queuing up governor
work items, register a utilization update callback that will be
invoked from the scheduler on utilization changes.

The sampling rate is still the same as what was used for the
deferrable timers and the added irq_work overhead should be offset by
the eliminated timers overhead, so in theory the functional impact of
this patch should not be significant.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
2016-03-09 14:40:53 +01:00
Arnd Bergmann
ddd30ef474 cpufreq: qoriq: allow building as module with THERMAL=m
My previous patch to avoid link errors with the qoriq cpufreq
driver disallowed all of the broken cases, but also prevented
the driver from being built when CONFIG_THERMAL is a module.

This changes the dependency to allow the cpufreq driver to
also be a module in this case, just not built-in.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 8ae1702a0d (cpufreq: qoriq: Register cooling device based on device tree)
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-03-01 02:43:05 +01:00
Tang Yuantian
2f249358ee cpufreq: qoriq: rename the driver
This driver works on all QorIQ platforms which include
ARM-based cores and PPC-based cores.
Rename it in order to represent better.

Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-18 22:35:16 +01:00
Pranith Kumar
83fe27ea53 rcu: Make SRCU optional by using CONFIG_SRCU
SRCU is not necessary to be compiled by default in all cases. For tinification
efforts not compiling SRCU unless necessary is desirable.

The current patch tries to make compiling SRCU optional by introducing a new
Kconfig option CONFIG_SRCU which is selected when any of the components making
use of SRCU are selected.

If we do not select CONFIG_SRCU, srcu.o will not be compiled at all.

   text    data     bss     dec     hex filename
   2007       0       0    2007     7d7 kernel/rcu/srcu.o

Size of arch/powerpc/boot/zImage changes from

   text    data     bss     dec     hex filename
 831552   64180   23944  919676   e087c arch/powerpc/boot/zImage : before
 829504   64180   23952  917636   e0084 arch/powerpc/boot/zImage : after

so the savings are about ~2000 bytes.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: resolve conflict due to removal of arch/ia64/kvm/Kconfig. ]
2015-01-06 11:04:29 -08:00
Viresh Kumar
f41f4815f8 cpufreq: Kconfig: Remove architecture specific menu entries
CPUFreq driver's Kconfig entries are added in Kconfig.<arch> files and they are
all included from the main Kconfig file using a menu entry. This creates another
level of (unnecessary) hierarchy within the menuconfig entries.

The problem occurs when there are drivers usable across architectures. Either
their config entry is duplicated in all the supported architectures or is put
into the main Kconfig entry. With the later one, we have menuconfig entries for
drivers at two levels then.

Fix these issues by getting rid of another level of menuconfig hierarchy and
populate all drivers within the main cpufreq menu. To clearly distinguish where
the drivers start from, also add a comment that will appear in menuconfig.

Reported-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Suggested-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-18 02:47:42 +01:00
Kelvin Cheung
a0a22cf144 cpufreq: Loongson1: Add cpufreq driver for Loongson1B
This patch adds cpufreq driver for Loongson1B which
is capable of changing the CPU frequency dynamically.

Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-06 01:23:44 +01:00
James Geboski
b3a826c05b cpufreq: allow powersave governor as the default without expert mode
The intel_pstate driver only supports the performance and the powersave
governors. With the performance governor ensuring the highest possible
performance settings, userspace tools fail to make any lasting changes.
In order to allow userspace tools to make modifications to the settings,
the powersave governor must be in use. This makes having the powersave
governor as the default convenient for systems where the intel_pstate
driver is being employed. Having to enable expert mode in the kernel
configuration is just a headache for such a trivial task.

This patch applies to all kernel versions 2.6.38 or greater after the
migration from CONFIG_EMBEDDED to CONFIG_EXPERT (6a108a14fa). Most
importantly, this applies to kernel versions 3.9 or greater when the
intel_pstate driver was introduced.

Signed-off-by: James Geboski <jgeboski@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-06 00:44:28 +01:00
Viresh Kumar
bbcf071969 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>
2014-10-03 15:37:54 +02:00
Arnd Bergmann
217886d3f3 cpufreq: cpufreq-cpu0: fix CPU_THERMAL dependency
5fbfbcd3e8 ("cpufreq: cpufreq-cpu0: remove dependency on THERMAL and
REGULATOR") was a little too quick in completely removing the dependency
on the THERMAL driver.

The problem is that while there are inline wrappers to turn the thermal
API calls into empty functions, those do not help if the cpu-thermal
driver is a loadable module and cpufreq-cpu0 is builtin.

Since CONFIG_CPU_THERMAL is a bool option that decides whether the cpu
code is built into the thermal module or not, we have to use a dependency
on the thermal driver itself. However, if CPU_THERMAL is disabled, we
don't need the dependency, hence the strange '!CPU_THERMAL || THERMAL'
construct.

Fixes: 5fbfbcd3e8 ("cpufreq: cpufreq-cpu0: remove dependency on THERMAL and REGULATOR")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-16 22:33:38 +02:00
Viresh Kumar
5fbfbcd3e8 cpufreq: cpufreq-cpu0: remove dependency on THERMAL and REGULATOR
cpufreq-cpu0 uses thermal framework to register a cooling device, but doesn't
depend on it as there are dummy calls provided by thermal layer when
CONFIG_THERMAL=n. And when these calls fail, the driver is still usable.

Similar explanation is valid for regulators as well. We do have dummy calls
available for regulator APIs and the driver can work even when those calls
fail.

So, we don't really need to mention thermal and regulators as a dependency for
cpufreq-cpu0 in Kconfig as platforms without support for thermal/regulator can
also use this driver. Remove this dependency.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-06-10 22:52:35 +02:00