Commit Graph

408 Commits

Author SHA1 Message Date
Lukasz Luba
015f569c46 Documentation: EM: Add artificial EM registration description
Add description about new artificial EM registration and use cases.
Update also the documentation with the new .get_cost() callback
description and usage.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:26:18 +02:00
Lukasz Luba
75a3a99a5a PM: EM: Change the order of arguments in the .active_power() callback
The .active_power() callback passes the device pointer when it's called.
Aligned with a convetion present in other subsystems and pass the 'dev'
as a first argument. It looks more cleaner.

Adjust all affected drivers which implement that API callback.

Suggested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-13 16:26:17 +02:00
Lukasz Luba
f48a0c475c Documentation: EM: Describe new registration method using DT
The new registration method allows to get power values from the DT OPP
definition. The new OPP entry property "opp-microwatt" contains total
power expressed in micro-Watts. Align the EM documentation with this
new possible registration method of EM.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2022-03-03 09:35:04 +05:30
Rafael J. Wysocki
78e6e4dfd8 Merge branches 'pm-opp', 'pm-devfreq' and 'powercap'
Merge an operating performance points (OPP) update, devfreq updates
and power capping updates for 5.17-rc1:

 - Update outdated OPP documentation (Tang Yizhou).

 - Reduce log severity for informative message regarding frequency
   transition failures in devfreq (Tzung-Bi Shih).

 - Add DRAM frequency controller devfreq driver for Allwinner sunXi
   SoCs (Samuel Holland).

 - Add missing COMMON_CLK dependency to the sun8i devfreq driver (Arnd
   Bergmann).

 - Add support for new layout of Psys PowerLimit Register on SPR to
   the Intel RAPL power capping driver (Zhang Rui).

 - Fix typo in a comment in idle_inject.c (Jason Wang).

 - Remove unused function definition from the DTPM (Dynamit Thermal
   Power Management) power capping framework (Daniel Lezcano).

 - Reduce DTPM trace verbosity (Daniel Lezcano).

* pm-opp:
  Documentation: power: Update outdated contents in opp.rst

* pm-devfreq:
  PM / devfreq: Reduce log severity for informative message
  PM / devfreq: sun8i: addd COMMON_CLK dependency
  PM / devfreq: Add a driver for the sun8i/sun50i MBUS

* powercap:
  powercap/drivers/dtpm: Reduce trace verbosity
  powercap/drivers/dtpm: Remove unused function definition
  powercap: fix typo in a comment in idle_inject.c
  powercap: intel_rapl: support new layout of Psys PowerLimit Register on SPR
2022-01-10 18:00:31 +01:00
Rafael J. Wysocki
ffb9bfa8e4 Merge branch 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm
Pull OPP (operating performance points) updates for 5.17-rc1 from Viresh
Kumar:

"This updates the documentation to match the latest code."

* 'opp/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm:
  Documentation: power: Update outdated contents in opp.rst
2021-12-30 15:53:41 +01:00
Tang Yizhou
489a00ef46 Documentation: power: Update outdated contents in opp.rst
Three problems have been revised:
1. CONFIG_PM_OPP no longer depends on CONFIG_PM.
2. opp_find_freq_{ceil, floor} is renamed as dev_pm_opp_find_freq_{ceil,
   floor}.
3. Make it clear that the 'opp' struct is actually dev_pm_opp.

Signed-off-by: Tang Yizhou <tangyizhou@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2021-12-27 09:47:52 +05:30
Rafael J. Wysocki
c24efa6732 PM: runtime: Capture device status before disabling runtime PM
In some cases (for example, during system-wide suspend and resume of
devices) it is useful to know whether or not runtime PM has ever been
enabled for a given device and, if so, what the runtime PM status of
it had been right before runtime PM was disabled for it last time.

For this reason, introduce a new struct dev_pm_info field called
last_status that will be used for capturing the runtime PM status of
the device when its power.disable_depth counter changes from 0 to 1.

The new field will be set to RPM_INVALID to start with and whenever
power.disable_depth changes from 1 to 0, so it will be valid only
when runtime PM of the device is currently disabled, but it has been
enabled at least once.

Immediately use power.last_status in rpm_resume() to make it handle
the case when PM runtime is disabled for the device, but its runtime
PM status is RPM_ACTIVE more consistently.  Namely, make it return 1
if power.last_status is also equal to RPM_ACTIVE in that case (the
idea being that if the status was RPM_ACTIVE last time when
power.disable_depth was changing from 0 to 1 and it is still
RPM_ACTIVE, it can be assumed to reflect what happened to the device
last time when it was using runtime PM) and -EACCES otherwise.

Update the documentation to provide a description of last_status and
change the description of pm_runtime_resume() in it to reflect the
new behavior of rpm_active().

While at it, rearrange the code in pm_runtime_enable() to be more
straightforward and replace the WARN() macro in it with a pr_warn()
invocation which is less disruptive.

Link: https://lore.kernel.org/linux-pm/20211026222626.39222-1-ulf.hansson@linaro.org/t/#u
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-12-17 16:16:40 +01:00
Lukasz Luba
08374410a5 Documentation: power: Describe 'advanced' and 'simple' EM models
The Energy Model (EM) can be registered in two ways:

 1) Using a helper function, which under the hood relies on OPP framework
    and DT entry in CPU node: 'dynamic-power-coefficient'. This is
    a 'simple' EM because it's tied to the math formula:
    Power = dynamic-power-coefficient * V^2 * f

 2) Using em_dev_register_perf_domain() API function with a driver
    custom callback which provides power for each performance state.

    This is 'advanced' EM, since it can better reflect real power
    measurements for each performance state. It's not limited to any
    math formula and can better reflect real physics of the device.

Add description of these two methods to the documentation, so developers
could choose the suitable registration method (option).

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-10 21:26:34 +01:00
Lukasz Luba
d704aa0d44 Documentation: power: Add description about new callback for EM registration
The Energy Model (EM) registration for CPUs should now be done using
a dedicated callback added recently into CPUFreq framework and drivers.

Commit c17495b01b ("cpufreq: Add callback to register with energy model")

The callback guaranties that the EM registration is called at the right
time during driver setup. To avoid mistakes update the documentation
to align with the existing code implementation.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-10 21:26:34 +01:00
Lukasz Luba
d62aab8ff7 Documentation: power: include kernel-doc in Energy Model doc
Improve the existing documentation of the Energy Model and add kernel-doc
comments. This extends an API description and helps better understanding
the usage.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-09-07 21:17:28 +02:00
Ulf Hansson
4ec4f05908 PM: runtime: Clarify documentation when callbacks are unassigned
Recent changes to the PM core allows ->runtime_suspend|resume callbacks to
be unassigned.

In the earlier behaviour the PM core would return -ENOSYS, when trying to
runtime resume a device, for example. Let's update the documentation to
clarify this.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-11 19:04:07 +02:00
Krzysztof Kozlowski
c58e7ed28b PM: runtime: document common mistake with pm_runtime_get_sync()
pm_runtime_get_sync(), contradictory to intuition, does not drop the
runtime PM usage counter on errors which lead to several wrong usages in
drivers (missing the put).  pm_runtime_resume_and_get() was added as a
better implementation so document the preference of using it, hoping it
will stop bad patterns.

Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
[ rjw: Documentation change edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-05-31 14:17:13 +02:00
Linus Torvalds
5a69e9bce9 Merge tag 'for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply
Pull power supply and reset updates from Sebastian Reichel:
 "battery/charger driver changes:
   - core:
      - provide function stubs if CONFIG_POWER_SUPPLY=n
      - reduce loglevel for probe defer info
   - surface:
      - new battery and charger drivers for Surface
   - bq27xxx:
      - add bq78z100 support
      - fix current_now/power_avg for newer chips
   - cw2015:
      - add CHARGE_NOW support
   - ab8500:
      - drop pdata support
   - convert most DT bindings to YAML
   - lots of minor fixes and cleanups

  reset drivers:
   - ltc2952-poweroff:
      - make trigger delay configurable from DT
   - minor fixes and cleanups"

* tag 'for-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply: (97 commits)
  power: supply: cpcap-battery: fix invalid usage of list cursor
  power: supply: bq256xx: add kerneldoc for structure members
  power: supply: act8945a: correct kerneldoc
  power: supply: max17040: remove unneeded double cast
  power: supply: max17040: handle device_property_read_u8_array() failure
  power: supply: max14577: remove unneeded variable initialization
  power: supply: surface-charger: Make symbol 'surface_ac_pm_ops' static
  power: supply: surface-battery: Make some symbols static
  power: reset: restart-poweroff: Add missing MODULE_DEVICE_TABLE
  power: reset: hisi-reboot: add missing MODULE_DEVICE_TABLE
  power: supply: s3c_adc_battery: fix possible use-after-free in s3c_adc_bat_remove()
  power: supply: generic-adc-battery: fix possible use-after-free in gab_remove()
  power: supply: Add AC driver for Surface Aggregator Module
  power: supply: Add battery driver for Surface Aggregator Module
  power: supply: bq25980: Move props from battery node
  power: supply: core: Use true and false for bool variable
  power: supply: goldfish: Remove the GOLDFISH dependency
  power: reset: ltc2952: make trigger delay configurable
  power: supply: cpcap-charger: Simplify bool conversion
  power: supply: cpcap-charger: Add usleep to cpcap charger to avoid usb plug bounce
  ...
2021-04-28 15:43:58 -07:00
Alan Stern
2c412337cf PM: runtime: Add documentation for pm_runtime_resume_and_get()
Commit dd8088d5a8 ("PM: runtime: Add pm_runtime_resume_and_get to
deal with usage counter") added a new runtime-PM API function without
updating the documentation in runtime_pm.rst.

Add the missing documentation.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: dd8088d5a8 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-09 17:24:28 +02:00
Mauro Carvalho Chehab
e4e4092938 dt-bindings: power: update battery.yaml reference
Changesets: 70c23e62d2 ("dt-bindings: power: supply: Fix remaining battery.txt links")
and: 471dec8023 ("dt-bindings: power: Convert battery.txt to battery.yaml")
renamed: Documentation/devicetree/bindings/power/supply/battery.txt
to: Documentation/devicetree/bindings/power/supply/battery.yaml.

Update its cross-reference accordingly.

Fixes: 70c23e62d2 ("dt-bindings: power: supply: Fix remaining battery.txt links")
Fixes: 471dec8023 ("dt-bindings: power: Convert battery.txt to battery.yaml")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2021-04-02 13:00:55 +02:00
Linus Torvalds
0e63a5c6ba Merge tag 'docs-5.12' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "It has been a relatively quiet cycle in docsland.

   - As promised, the minimum Sphinx version to build the docs is now
     1.7, and we have dropped support for Python 2 entirely. That
     allowed the removal of a bunch of compatibility code.

   - A set of treewide warning fixups from Mauro that I applied after it
     became clear nobody else was going to deal with them.

   - The automarkup mechanism can now create cross-references from
     relative paths to RST files.

   - More translations, typo fixes, and warning fixes"

* tag 'docs-5.12' of git://git.lwn.net/linux: (75 commits)
  docs: kernel-hacking: be more civil
  docs: Remove the Microsoft rhetoric
  Documentation/admin-guide: kernel-parameters: Update nohlt section
  doc/admin-guide: fix spelling mistake: "perfomance" -> "performance"
  docs: Document cross-referencing using relative path
  docs: Enable usage of relative paths to docs on automarkup
  docs: thermal: fix spelling mistakes
  Documentation: admin-guide: Update kvm/xen config option
  docs: Make syscalls' helpers naming consistent
  coding-style.rst: Avoid comma statements
  Documentation: /proc/loadavg: add 3 more field descriptions
  Documentation/submitting-patches: Add blurb about backtraces in commit messages
  Docs: drop Python 2 support
  Move our minimum Sphinx version to 1.7
  Documentation: input: define ABS_PRESSURE/ABS_MT_PRESSURE resolution as grams
  scripts/kernel-doc: add internal hyperlink to DOC: sections
  Update Documentation/admin-guide/sysctl/fs.rst
  docs: Update DTB format references
  docs: zh_CN: add iio index.rst translation
  docs/zh_CN: add iio ep93xx_adc.rst translation
  ...
2021-02-22 10:57:46 -08:00
Rafael J. Wysocki
a9a939cb34 Merge branches 'powercap' and 'pm-misc'
* powercap:
  powercap: intel_rapl: Use topology interface in rapl_init_domains()
  powercap: intel_rapl: Use topology interface in rapl_add_package()
  powercap/intel_rapl: add support for AlderLake Mobile
  powercap/drivers/dtpm: Fix size of object being allocated
  powercap/drivers/dtpm: Fix an IS_ERR() vs NULL check
  powercap/drivers/dtpm: Fix some missing unlock bugs
  powercap/drivers/dtpm: Fix a double shift bug
  powercap/drivers/dtpm: Fix __udivdi3 and __aeabi_uldivmod unresolved symbols
  powercap/drivers/dtpm: Add CPU energy model based support
  powercap/drivers/dtpm: Add API for dynamic thermal power management
  Documentation/powercap/dtpm: Add documentation for dtpm
  units: Add Watt units

* pm-misc:
  PM: Kconfig: remove unneeded "default n" options
  PM: EM: update Kconfig description and drop "default n" option
2021-02-15 18:50:01 +01:00
Bjorn Helgaas
309663093c PM: runtime: Fix typos and grammar
Fix minor typos and grammatical issues.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-27 19:23:38 +01:00
Joe Perches
05a5f51ca5 Documentation: Replace lkml.org links with lore
Replace the lkml.org links with lore to better use a single source
that's more likely to stay available long-term.

Done by bash script:

cvt_lkml_to_lore ()
{
    tmpfile=$(mktemp ./.cvt_links.XXXXXXX)

    header=$(echo $1 | sed 's@/lkml/@/lkml/headers/@')

    wget -qO - $header > $tmpfile
    if [[ $? == 0 ]] ; then
	link=$(grep -i '^Message-Id:' $tmpfile | head -1 | \
		   sed -r -e 's/^\s*Message-Id:\s*<\s*//' -e  's/\s*>\s*$//' -e 's@^@https://lore.kernel.org/r/@')
	#    echo "testlink: $link"
	if [ -n "$link" ] ; then
	    wget -qO - $link > /dev/null
	    if [[ $? == 0 ]] ; then
		echo $link
	    fi
	fi
    fi

    rm -f $tmpfile
}

git grep -P -o "\bhttps?://(?:www.)?lkml.org/lkml[\/\w]+" $@ |
    while read line ; do
	echo $line
	file=$(echo $line | cut -f1 -d':')
	link=$(echo $line | cut -f2- -d':')
	newlink=$(cvt_lkml_to_lore $link)
	if [[ -n "$newlink" ]] ; then
	    sed -i -e "s#\b$link\b#$newlink#" $file
	fi
    done

Link: https://lore.kernel.org/patchwork/patch/1265849/#1462688
Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/77cdb7f32cfb087955bfc3600b86c40bed5d4104.camel@perches.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-11 12:47:38 -07:00
Daniel Lezcano
f5ad1c7479 Documentation/powercap/dtpm: Add documentation for dtpm
The dynamic thermal and power management is a technique to dynamically
adjust the power consumption of different devices in order to ensure a
global thermal constraint.

An userspace daemon is usually monitoring the temperature and the
power to take immediate action on the device.

The DTPM framework provides an unified API to userspace to act on the
power.

Document this framework.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-12-22 19:50:40 +01:00
Lukasz Luba
b56a352c0d PM: EM: Update Energy Model with new flag indicating power scale
Update description and meaning of a new flag, which indicates the type of
power scale used for a registered Energy Model (EM) device.

Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10 20:29:28 +01:00
Lukasz Luba
5a64f77569 PM: EM: Clarify abstract scale usage for power values in Energy Model
The Energy Model (EM) can store power values in milli-Watts or in abstract
scale. This might cause issues in the subsystems which use the EM for
estimating the device power, such as:

 - mixing of different scales in a subsystem which uses multiple
   (cooling) devices (e.g. thermal Intelligent Power Allocation (IPA))

 - assuming that energy [milli-Joules] can be derived from the EM power
   values which might not be possible since the power scale doesn't have
   to be in milli-Watts

To avoid misconfiguration add the requisite documentation to the EM and
related subsystems: EAS and IPA.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10 20:29:28 +01:00
Krzysztof Wilczyński
3789af9a13 PCI/PM: Rename pci_dev.d3_delay to d3hot_delay
PCI devices support two variants of the D3 power state: D3hot (main power
present) D3cold (main power removed).  Previously struct pci_dev contained:

  unsigned int    d3_delay;       /* D3->D0 transition time in ms */
  unsigned int    d3cold_delay;   /* D3cold->D0 transition time in ms */

"d3_delay" refers specifically to the D3hot state.  Rename it to
"d3hot_delay" to avoid ambiguity and align with the ACPI "_DSM for
Specifying Device Readiness Durations" in the PCI Firmware spec r3.2,
sec 4.6.9.

There is no change to the functionality.

Link: https://lore.kernel.org/r/20200730210848.1578826-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-09-29 14:21:50 -05:00
Rafael J. Wysocki
86ba54fb08 Merge branches 'pm-sleep', 'pm-domains', 'powercap' and 'pm-tools'
* pm-sleep:
  PM: sleep: spread "const char *" correctness
  PM: hibernate: fix white space in a few places
  freezer: Add unsafe version of freezable_schedule_timeout_interruptible() for NFS
  PM: sleep: core: Emit changed uevent on wakeup_sysfs_add/remove

* pm-domains:
  PM: domains: Restore comment indentation for generic_pm_domain.child_links
  PM: domains: Fix up terminology with parent/child

* powercap:
  powercap: Add Power Limit4 support
  powercap: idle_inject: Replace play_idle() with play_idle_precise() in comments
  powercap: intel_rapl: add support for Sapphire Rapids

* pm-tools:
  pm-graph v5.7 - important s2idle fixes
  cpupower: Replace HTTP links with HTTPS ones
  cpupower: Fix NULL but dereferenced coccicheck errors
  cpupower: Fix comparing pointer to 0 coccicheck warns
2020-08-03 13:12:44 +02:00
Sumeet Pawnikar
8365a898fe powercap: Add Power Limit4 support
Modern Intel Mobile platforms support power limit4 (PL4), which is
the SoC package level maximum power limit (in Watts). It can be used
to preemptively limits potential SoC power to prevent power spikes
from tripping the power adapter and battery over-current protection.
This patch enables this feature by exposing package level peak power
capping control to userspace via RAPL sysfs interface. With this,
application like DTPF can modify PL4 power limit, the similar way
of other package power limit (PL1).
As this feature is not tested on previous generations, here it is
enabled only for the platform that has been verified to work,
for safety concerns.

Signed-off-by: Sumeet Pawnikar <sumeet.r.pawnikar@intel.com>
Co-developed-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-07-27 14:17:36 +02:00