PM / devfreq: Reorder fields in 'struct devfreq_dev_status'

Group some variables based on their sizes to reduce holes.
On x86_64, this shrinks the size of 'struct devfreq_dev_status' from 72 to
64 b

PM / devfreq: Reorder fields in 'struct devfreq_dev_status'

Group some variables based on their sizes to reduce holes.
On x86_64, this shrinks the size of 'struct devfreq_dev_status' from 72 to
64 bytes.

This structure is used both to allocate static variables or is embedded in
some other structures. In both cases, reducing its size is nice to have.

Moreover, the whole structure now fits in a single cache line on x86_64.

Finally, it makes the order of code match the order of the above kernel
doc.

Signed-off-by: Christophe JAILLET <[email protected]>
Acked-by: MyungJoo Ham <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Fix build issues with devfreq disabled

The existing no-op shims for when PM_DEVFREQ (or an individual governor)
only do half the job. The governor specific config/tuning structs need

PM / devfreq: Fix build issues with devfreq disabled

The existing no-op shims for when PM_DEVFREQ (or an individual governor)
only do half the job. The governor specific config/tuning structs need
to be available to avoid compile errors in drivers using devfreq.

Fixes: 6563f60f14cb ("drm/msm/gpu: Add devfreq tuning debugfs")
Signed-off-by: Rob Clark <[email protected]>
Acked-by: MyungJoo Ham <[email protected]>
Acked-by: Chanwoo Choi <[email protected]>
Patchwork: https://patchwork.freedesktop.org/patch/519801/
Link: https://lore.kernel.org/r/[email protected]

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PM/devfreq: governor: Add a private governor_data for governor

The member void *data in the structure devfreq can be overwrite
by governor_userspace. For example:
1. The device driver assigned the d

PM/devfreq: governor: Add a private governor_data for governor

The member void *data in the structure devfreq can be overwrite
by governor_userspace. For example:
1. The device driver assigned the devfreq governor to simple_ondemand
by the function devfreq_add_device() and init the devfreq member
void *data to a pointer of a static structure devfreq_simple_ondemand_data
by the function devfreq_add_device().
2. The user changed the devfreq governor to userspace by the command
"echo userspace > /sys/class/devfreq/.../governor".
3. The governor userspace alloced a dynamic memory for the struct
userspace_data and assigend the member void *data of devfreq to
this memory by the function userspace_init().
4. The user changed the devfreq governor back to simple_ondemand
by the command "echo simple_ondemand > /sys/class/devfreq/.../governor".
5. The governor userspace exited and assigned the member void *data
in the structure devfreq to NULL by the function userspace_exit().
6. The governor simple_ondemand fetched the static information of
devfreq_simple_ondemand_data in the function
devfreq_simple_ondemand_func() but the member void *data of devfreq was
assigned to NULL by the function userspace_exit().
7. The information of upthreshold and downdifferential is lost
and the governor simple_ondemand can't work correctly.

The member void *data in the structure devfreq is designed for
a static pointer used in a governor and inited by the function
devfreq_add_device(). This patch add an element named governor_data
in the devfreq structure which can be used by a governor(E.g userspace)
who want to assign a private data to do some private things.

Fixes: ce26c5bb9569 ("PM / devfreq: Add basic governors")
Cc: [email protected] # 5.10+
Reviewed-by: Chanwoo Choi <[email protected]>
Acked-by: MyungJoo Ham <[email protected]>
Signed-off-by: Kant Fan <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Rework freq_table to be local to devfreq struct

On a devfreq PROBE_DEFER, the freq_table in the driver profile struct,
is never reset and may be leaved in an undefined state.

This com

PM / devfreq: Rework freq_table to be local to devfreq struct

On a devfreq PROBE_DEFER, the freq_table in the driver profile struct,
is never reset and may be leaved in an undefined state.

This comes from the fact that we store the freq_table in the driver
profile struct that is commonly defined as static and not reset on
PROBE_DEFER.
We currently skip the reinit of the freq_table if we found
it's already defined since a driver may declare his own freq_table.

This logic is flawed in the case devfreq core generate a freq_table, set
it in the profile struct and then PROBE_DEFER, freeing the freq_table.
In this case devfreq will found a NOT NULL freq_table that has been
freed, skip the freq_table generation and probe the driver based on the
wrong table.

To fix this and correctly handle PROBE_DEFER, use a local freq_table and
max_state in the devfreq struct and never modify the freq_table present
in the profile struct if it does provide it.

Fixes: 0ec09ac2cebe ("PM / devfreq: Set the freq_table of devfreq device")
Cc: [email protected]
Signed-off-by: Christian Marangi <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: passive: Keep cpufreq_policy for possible cpus

The passive governor requires the cpu data to get the next target frequency
of devfreq device if depending on cpu. In order to reduce the

PM / devfreq: passive: Keep cpufreq_policy for possible cpus

The passive governor requires the cpu data to get the next target frequency
of devfreq device if depending on cpu. In order to reduce the unnecessary
memory data, keep cpufreq_policy data for possible cpus instead of NR_CPU.

Tested-by: Chen-Yu Tsai <[email protected]>
Tested-by: Johnson Wang <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Add cpu based scaling support to passive governor

Many CPU architectures have caches that can scale independent of the
CPUs. Frequency scaling of the caches is necessary to make sure t

PM / devfreq: Add cpu based scaling support to passive governor

Many CPU architectures have caches that can scale independent of the
CPUs. Frequency scaling of the caches is necessary to make sure that the
cache is not a performance bottleneck that leads to poor performance and
power. The same idea applies for RAM/DDR.

To achieve this, this patch adds support for cpu based scaling to the
passive governor. This is accomplished by taking the current frequency
of each CPU frequency domain and then adjust the frequency of the cache
(or any devfreq device) based on the frequency of the CPUs. It listens
to CPU frequency transition notifiers to keep itself up to date on the
current CPU frequency.

To decide the frequency of the device, the governor does one of the
following:
* Derives the optimal devfreq device opp from required-opps property of
the parent cpu opp_table.

* Scales the device frequency in proportion to the CPU frequency. So, if
the CPUs are running at their max frequency, the device runs at its
max frequency. If the CPUs are running at their min frequency, the
device runs at its min frequency. It is interpolated for frequencies
in between.

Tested-by: Chen-Yu Tsai <[email protected]>
Tested-by: Johnson Wang <[email protected]>
Signed-off-by: Saravana Kannan <[email protected]>
[Sibi: Integrated cpu-freqmap governor into passive_governor]
Signed-off-by: Sibi Sankar <[email protected]>
[Chanwoo: Fix conflict with latest code and cleanup code]
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Register devfreq as a cooling device on demand

Currently the default behavior is to manually having the devfreq
backend to register themselves as a devfreq cooling device.

Instead of

PM / devfreq: Register devfreq as a cooling device on demand

Currently the default behavior is to manually having the devfreq
backend to register themselves as a devfreq cooling device.

Instead of adding the code in the drivers for the thermal cooling
device registering, let's provide a flag in the devfreq's profile to
tell the common devfreq code to register the newly created devfreq as
a cooling device.

Suggested-by: Chanwoo Choi <[email protected]>
Signed-off-by: Daniel Lezcano <[email protected]>
Reviewed-by: Steven Price <[email protected]>
Reviewed-by: Lukasz Luba <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Cache OPP table reference in devfreq

The OPP table can be used often in devfreq. Trying to get it each time can
be expensive, so cache it in the devfreq struct.

Signed-off-by: Saravan

PM / devfreq: Cache OPP table reference in devfreq

The OPP table can be used often in devfreq. Trying to get it each time can
be expensive, so cache it in the devfreq struct.

Signed-off-by: Saravana Kannan <[email protected]>
Acked-by: MyungJoo Ham <[email protected]>
Acked-by: Chanwoo Choi <[email protected]>
Signed-off-by: Hsin-Yi Wang <[email protected]>
[ Viresh: Added a blank line ]
Signed-off-by: Viresh Kumar <[email protected]>

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PM / devfreq: Remove redundant governor_name from struct devfreq

The devfreq structure instance contains the governor_name and a governor
instance. When need to show the governor name, better to use

PM / devfreq: Remove redundant governor_name from struct devfreq

The devfreq structure instance contains the governor_name and a governor
instance. When need to show the governor name, better to use the name
of devfreq_governor structure. So, governor_name variable in struct devfreq
is a redundant and unneeded variable. Remove the redundant governor_name
of struct devfreq and then use the name of devfreq_governor instance.

Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: remove a duplicated kernel-doc markup

The update_devfreq() is also documented at devfreq.c, which
has a more complete note.

So, drop the duplicated markup, in order to avoid this
warn

PM / devfreq: remove a duplicated kernel-doc markup

The update_devfreq() is also documented at devfreq.c, which
has a more complete note.

So, drop the duplicated markup, in order to avoid this
warning:
.../Documentation/driver-api/device_link.rst: WARNING: Duplicate C declaration, also defined in 'driver-api/infrastructure'.
Declaration is 'device_link_state'.

(and to cause a problem with cross-references to it)

Signed-off-by: Mauro Carvalho Chehab <[email protected]>

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PM / devfreq: Change prototype of devfreq_get_devfreq_by_phandle function

Previously, devfreq core support 'devfreq' property in order to get
the devfreq device by phandle. But, 'devfreq' property n

PM / devfreq: Change prototype of devfreq_get_devfreq_by_phandle function

Previously, devfreq core support 'devfreq' property in order to get
the devfreq device by phandle. But, 'devfreq' property name is not proper
on devicetree binding because this name doesn't mean the any h/w attribute.

The devfreq core hand over the right to decide the property name
for getting the devfreq device on devicetree. Each devfreq driver
will decide the property name on devicetree binding and pass
the their own property name to devfreq_get_devfreq_by_phandle function.

Acked-by: Krzysztof Kozlowski <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Add devfreq_get_devfreq_by_node function

Split off part of devfreq_get_devfreq_by_phandle into a separate
function. This allows callers to fetch devfreq instances by enumerating
device

PM / devfreq: Add devfreq_get_devfreq_by_node function

Split off part of devfreq_get_devfreq_by_phandle into a separate
function. This allows callers to fetch devfreq instances by enumerating
devicetree instead of explicit phandles.

Acked-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Lukasz Luba <[email protected]>
Signed-off-by: Leonard Crestez <[email protected]>
[cw00.choi: Export devfreq_get_devfreq_by_node function and
add function to devfreq.h when CONFIG_PM_DEVFREQ is enabled.]
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Add support delayed timer for polling mode

Until now, the devfreq driver using polling mode like simple_ondemand
governor have used only deferrable timer for reducing the redundant
pow

PM / devfreq: Add support delayed timer for polling mode

Until now, the devfreq driver using polling mode like simple_ondemand
governor have used only deferrable timer for reducing the redundant
power consumption. It reduces the CPU wake-up from idle due to polling mode
which check the status of Non-CPU device.

But, it has a problem for Non-CPU device like DMC device with DMA operation.
Some Non-CPU device need to do monitor continuously regardless of CPU state
in order to decide the proper next status of Non-CPU device.

So, add support the delayed timer for polling mode to support
the repetitive monitoring. The devfreq driver and user can select
the kind of timer on either deferrable and delayed timer.

For example, change the timer type of DMC device
based on Exynos5422-based Odroid-XU3 as following:

- If want to use deferrable timer as following:
echo deferrable > /sys/class/devfreq/10c20000.memory-controller/timer

- If want to use delayed timer as following:
echo delayed > /sys/class/devfreq/10c20000.memory-controller/timer

Reviewed-by: Bartlomiej Zolnierkiewicz <[email protected]>
Reviewed-by: Lukasz Luba <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Get rid of some doc warnings

Mark "void *data" as literal, in order to avoid those doc warnings:

./include/linux/devfreq.h:156: WARNING: Inline emphasis start-string without end-stri

PM / devfreq: Get rid of some doc warnings

Mark "void *data" as literal, in order to avoid those doc warnings:

./include/linux/devfreq.h:156: WARNING: Inline emphasis start-string without end-string.
./include/linux/devfreq.h:259: WARNING: Inline emphasis start-string without end-string.
./include/linux/devfreq.h:279: WARNING: Inline emphasis start-string without end-string.

Signed-off-by: Mauro Carvalho Chehab <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Remove unneeded extern keyword

Remove unneeded extern keyword from devfreq-related header file
and adjust the indentation of function parameter to keep the
consistency in header file

PM / devfreq: Remove unneeded extern keyword

Remove unneeded extern keyword from devfreq-related header file
and adjust the indentation of function parameter to keep the
consistency in header file

Reviewed-by: Lukasz Luba <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Fix multiple kernel-doc warnings

Fix kernel-doc warnings in devfreq files.
Also fix a typo.

Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Chanwoo Choi <cw00.choi@

PM / devfreq: Fix multiple kernel-doc warnings

Fix kernel-doc warnings in devfreq files.
Also fix a typo.

Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Move statistics to separate struct devfreq_stats

Count time and transitions between devfreq frequencies in separate
struct devfreq_stats for improved code readability and maintenance.

PM / devfreq: Move statistics to separate struct devfreq_stats

Count time and transitions between devfreq frequencies in separate
struct devfreq_stats for improved code readability and maintenance.

Signed-off-by: Kamil Konieczny <[email protected]>
Reviewed-by: Matthias Kaehlcke <[email protected]>
[cw00.choi: Fix the merge conflict in trasn_stat_store
and use 'devfreq->stats.*' style for consistent coding style
and restore the clean-up code of 'devfreq->profile->*']
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Change time stats to 64-bit

Change time stats counting to bigger type by using 64-bit jiffies.
This will make devfreq stats code look similar to cpufreq stats and
prevents overflow (fo

PM / devfreq: Change time stats to 64-bit

Change time stats counting to bigger type by using 64-bit jiffies.
This will make devfreq stats code look similar to cpufreq stats and
prevents overflow (for HZ = 1000 after 49.7 days).

Signed-off-by: Kamil Konieczny <[email protected]>
Acked-by: Chanwoo Choi <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Use PM QoS for sysfs min/max_freq

Switch the handling of min_freq and max_freq from sysfs to use the
dev_pm_qos_request interface.

Since PM QoS handles frequencies as kHz this change

PM / devfreq: Use PM QoS for sysfs min/max_freq

Switch the handling of min_freq and max_freq from sysfs to use the
dev_pm_qos_request interface.

Since PM QoS handles frequencies as kHz this change reduces the
precision of min_freq and max_freq. This shouldn't introduce problems
because frequencies which are not an integer number of kHz are likely
not an integer number of Hz either.

Try to ensure compatibility by rounding min values down and rounding
max values up.

Signed-off-by: Leonard Crestez <[email protected]>
Acked-by: Chanwoo Choi <[email protected]>
Reviewed-by: Matthias Kaehlcke <[email protected]>
Tested-by: Matthias Kaehlcke <[email protected]>
[cw00.choi: Return -EAGAIN instead of -EINVAL if dev_pm_qos is inactive]
Signed-off-by: Chanwoo Choi <[email protected]>

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PM / devfreq: Add PM QoS support

Register notifiers with the PM QoS framework in order to respond to
requests for DEV_PM_QOS_MIN_FREQUENCY and DEV_PM_QOS_MAX_FREQUENCY.

No notifiers are added by th

PM / devfreq: Add PM QoS support

Register notifiers with the PM QoS framework in order to respond to
requests for DEV_PM_QOS_MIN_FREQUENCY and DEV_PM_QOS_MAX_FREQUENCY.

No notifiers are added by this patch but PM QoS constraints can be
imposed externally (for example from other devices).

Signed-off-by: Leonard Crestez <[email protected]>
Acked-by: Chanwoo Choi <[email protected]>
Reviewed-by: Matthias Kaehlcke <[email protected]>
Tested-by: Matthias Kaehlcke <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Enrico Weigelt <[email protected]>
Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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PM / devfreq: add devfreq_suspend/resume() functions

This patch adds implementation for global suspend/resume for
devfreq framework. System suspend will next use these functions.

Suggested-by: Tobi

PM / devfreq: add devfreq_suspend/resume() functions

This patch adds implementation for global suspend/resume for
devfreq framework. System suspend will next use these functions.

Suggested-by: Tobias Jakobi <[email protected]>
Suggested-by: Chanwoo Choi <[email protected]>
Signed-off-by: Lukasz Luba <[email protected]>
Reviewed-by: Chanwoo Choi <[email protected]>
Signed-off-by: MyungJoo Ham <[email protected]>

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PM / devfreq: add support for suspend/resume of a devfreq device

The patch prepares devfreq device for handling suspend/resume
functionality. The new fields will store needed information during this

PM / devfreq: add support for suspend/resume of a devfreq device

The patch prepares devfreq device for handling suspend/resume
functionality. The new fields will store needed information during this
process. Devfreq framework handles opp-suspend DT entry and there is no
need of modyfications in the drivers code. It uses atomic variables to
make sure no race condition affects the process.

Suggested-by: Tobias Jakobi <[email protected]>
Suggested-by: Chanwoo Choi <[email protected]>
Signed-off-by: Lukasz Luba <[email protected]>
Reviewed-by: Chanwoo Choi <[email protected]>
Signed-off-by: MyungJoo Ham <[email protected]>

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PM / devfreq: Make update_devfreq() public

Currently update_devfreq() is only visible to devfreq governors outside
of devfreq.c. Make it public to allow drivers that adjust devfreq policies
to cause

PM / devfreq: Make update_devfreq() public

Currently update_devfreq() is only visible to devfreq governors outside
of devfreq.c. Make it public to allow drivers that adjust devfreq policies
to cause a re-evaluation of the frequency after a policy change.

Signed-off-by: Matthias Kaehlcke <[email protected]>
Reviewed-by: Brian Norris <[email protected]>
Reviewed-by: Chanwoo Choi <[email protected]>
Signed-off-by: MyungJoo Ham <[email protected]>

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PM / devfreq: Define the constant governor name

Prior to that, the devfreq device uses the governor name when adding
the itself. In order to prevent the mistake used the wrong governor name,
this pa

PM / devfreq: Define the constant governor name

Prior to that, the devfreq device uses the governor name when adding
the itself. In order to prevent the mistake used the wrong governor name,
this patch defines the governor name as a constant and then uses them
instead of using the string directly.

Signed-off-by: Chanwoo Choi <[email protected]>
Signed-off-by: MyungJoo Ham <[email protected]>
Cc: Kukjin Kim <[email protected]>
Cc: Krzysztof Kozlowski <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

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