As the definition of struct cpufreq_freqs has changed, update core.rst
with the new first member of struct cpufreq_freqs.
Signed-off-by: Tang Yizhou <tangyizhou@huawei.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This isn't used anymore, get rid of it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit e3c0623608 ("cpufreq: add cpufreq_driver_resolve_freq()")
introduced this callback, back in 2016, for drivers that provide the
->target() callback.
The kernel hasn't seen a single user of it in the past 5 years and
it is not likely to be used any time soon.
Remove it for now.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Now that all users of ->stop_cpu() have been migrated to using other
callbacks, drop it from the core.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Minor edits in the subject and changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Add a SPDX header;
- Add a document title, based on the original contents of
cpu-freq/index.txt;
- Use lists where needed;
- Comment out the existing text-only index;
- Adjust some title marks;
- Use bold on some places;
- Mark literal blocks as such;
- Some whitespace fixes and new line breaks;
- Add it to cpu-freq/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Add a SPDX header;
- Add a document title, based on the original contents of
cpu-freq/index.txt;
- Use lists where needed;
- Comment out the existing text-only index;
- Adjust some title marks;
- Add table markups;
- Add notes markups;
- Mark literal blocks as such;
- use ``foo`` for literal texts;
- Some whitespace fixes and new line breaks;
- Add it to cpu-freq/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- Add a SPDX header;
- Adjust the document title, based on the original contents of
cpu-freq/index.txt;
- Use lists where needed;
- Comment out the existing text-only index;
- use ``foo`` to mark a literal expression with asterisk;
- Adjust some title marks;
- Add table markups;
- Add notes markups;
- Some whitespace fixes and new line breaks;
- Add it to cpu-freq/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
most of the stuff there can be re-used with ReST format,
but we need to add an empty TOC and remove the existing
entries, as the following conversion patches will be re-adding
them, as they're converted.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are three legacy driver documents in Documentation/cpu-freq/
that were added years ago and converting them each to the .rst
format is rather pointless, even though there is some value in
preserving them. However, if they are preserved, they need to go
into the admin-guide part of cpufreq documentation where they belong
(at least to a certain extent).
To preserve them with minimum amount of changes and put them into the
right place, and make it possible to process them into HTML (and other
formats) along with the rest of the documentation, move them each
as a "literal text" block into a separate section of a single .rst
"wrapper" file under Documentation/admin-guide/pm/.
While at it, repair the PCC specification URL in one of them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Update documentation with the recent policy notifier updates.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Convert the PM documents to ReST, in order to allow them to
build with Sphinx.
The conversion is actually:
- add blank lines and indentation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.
At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
The order in which the frequencies are displayed in cpufreq stats
depends on the order in which the frequencies were sorted in the
frequency table provided to cpufreq core by the cpufreq driver. They can
be completely unsorted as well.
The documentation's claim that the stats will be sorted in descending
order is hence incorrect and here is an attempt to fix it.
Reported-by: Pavel <pavel2000@ngs.ru>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This isn't used anymore. Remove the helper and update documentation
accordingly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pointer subtraction is slow and tedious. Therefore, replace all instances
where cpufreq_for_each_{valid_,}entry loops contained such substractions
with an iteration macro providing an index to the frequency_table entry.
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Link: http://lkml.kernel.org/r/20180120020237.GM13338@ZenIV.linux.org.uk
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On platforms with large number of Pstates, the transition table, which
is a NxN matrix, can overflow beyond the PAGE_SIZE boundary.
This can be seen on POWER9 which has 100+ Pstates.
As a result, each time the trans_table is read for any of the CPUs, we
will get the following error.
---------------------------------------------------
fill_read_buffer: show+0x0/0xa0 returned bad count
---------------------------------------------------
This patch ensures that in case of an overflow, we print a warning
once in the dmesg and return FILE TOO LARGE error for this and all
subsequent accesses of trans_table.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 33fc30b470 (cpufreq: intel_pstate: Document the current
behavior and user interface) dropped the intel-pstate.txt file
from Documentation/cpu-freq/, but it did not update the index.txt
file in there accordingly, so do that now.
Fixes: 33fc30b470 (cpufreq: intel_pstate: Document the current behavior and user interface)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add a document describing the current behavior and user space
interface of the intel_pstate driver in the RST format and
drop the existing outdated intel_pstate.txt document.
Also update admin-guide/pm/cpufreq.rst with proper RST references
to the new intel_pstate.rst document.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The user/admin documentation of cpufreq is badly outdated. It
conains stale and/or inaccurate information along with things
that are not particularly useful. Also, some of the important
pieces are missing from it.
For this reason, add a new user/admin document for cpufreq
containing current information to admin-guide and drop the old
outdated .txt documents it is replacing.
Since there will be more PM documents in admin-guide going forward,
create a separate directory for them and put the cpufreq document
in there right away.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The patch replaces 'to to' with 'to' in the documentation.
Signed-off-by: sayli karnik <karniksayli1995@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Three more DocBook template files have been converted to RST; only 21 to
go. There are various build improvements and the usual array of
documentation improvements and fixes.
-----BEGIN PGP SIGNATURE-----
iQIcBAABAgAGBQJYriFXAAoJEI3ONVYwIuV6iTMP/iV7ownq9IK1f8askcXKM76i
NoRdj4/JywAPQ73vLhOSDVELGdVJNRBjdyOdBRzxPgsqAhFmm79lVYV2eLIffQ2k
7LcVbEQR77I+4z9SwqIVbIWNCBry7Hu8aWh7moDL3I6yeuay408yr5YW2lIlsqHZ
V/LZgkTWDe+iQPeXNA4Djzylx0lcRlAy4yMSLjN1+gb9/uBnXb9J0eGJzgfZfrL8
fiIhymg3bv8vB99l6LMR5vT343QLWXf1yS31A7rPQvwkDo6zFehUJA0XNfIsl2dw
VQYsvl9vp9wy3e6Y0qKXPn1XhAhCrm64P3crBxK31MMvcKZVCfeRSZ78wrvpvewy
MVLlXdqop1bHPHowtRfA5jwxr1NqcYp+Jg0+YGX3iXpPi1Jfk36DNUy9iWvtvIzr
lWgQcIKsdCwwYUcvPR8Kt8T/3q/AHbYlI6mimWlkmbZwncQcgCrH5xSG+c2BIPfV
fn3W6eLHBn8RyVsxlaXlA0Y9TNtI/Cm85b3Ri10pFvhl868ppWfJxXHi7UtcbU58
sQzahISCTXOH/NQwkkh7kFMtczbB43rAcChvF7EUYpazVBpJ4P4HxKFg3eIzIdc6
VlBSaMu1hxUGoYxNNYuKr/nYstuczLOKzK7q4j/JOExY3RgTWP+T3bF02wgubvoa
D/9WfScewkgCJRoA7i17
=C5nd
-----END PGP SIGNATURE-----
Merge tag 'docs-4.11' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A slightly quieter cycle for documentation this time around.
Three more DocBook template files have been converted to RST; only 21
to go. There are various build improvements and the usual array of
documentation improvements and fixes"
* tag 'docs-4.11' of git://git.lwn.net/linux: (44 commits)
docs / driver-api: Fix structure references in device_link.rst
PM / docs: Fix structure references in device.rst
Add a target to check broken external links in the Documentation
Documentation: Fix linux-api list typo
Documentation: DocBook/Makefile comment typo
Improve sparse documentation
Documentation: make Makefile.sphinx no-ops quieter
Documentation: DMA-ISA-LPC.txt
Documentation: input: fix path to input code definitions
docs: Remove the copyright year from conf.py
docs: Fix a warning in the Korean HOWTO.rst translation
PM / sleep / docs: Convert PM notifiers document to reST
PM / core / docs: Convert sleep states API document to reST
PM / core: Update kerneldoc comments in pm.h
doc-rst: Fix recursive make invocation from macros
doc-rst: Delete output of failed dot-SVG conversion
doc-rst: Break shell command sequences on failure
Documentation/sphinx: make targets independent of Sphinx work for HAVE_SPHINX=0
doc-rst: fixed cleandoc target when used with O=dir
Documentation/sphinx: prevent generation of .pyc files in the source tree
...
Make it possible to change the operation mode of intel_pstate with
the help of a new sysfs attribute called "status".
There are three possible configurations that can be selected using
this attribute:
"off" - The driver is not in use at this time.
"active" - The driver works as a P-state governor (default).
"passive" - The driver works as a regular cpufreq one and collaborates
with the generic cpufreq governors (it sets P-states as
requested by those governors). [This is the same mode
the driver can be started in by passing intel_pstate=passive
in the kernel command line.]
The current setting is returned by reads from this attribute. Writing
one of the above strings to it changes the operation mode as indicated
by that string, if possible.
If HW-managed P-states (HWP) feature is enabled, it is not possible
to change the driver's operation mode and attempts to write to this
attribute will fail.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq core has gone though lots of updates in recent times, but on
many occasions the documentation wasn't updated along with the code.
This patch tries to catchup the documentation with the code.
Also add Rafael and Viresh as the contributors to the documentation.
Based on a patch from Claudio Scordino.
Signed-off-by: Claudio Scordino <claudio@evidence.eu.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch doesn't change the content of the documentation, but rather
reformat it to make it more readable.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Updated documentation for the support of energy performance hint in
the HWP mode.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Allow CPUfreq statistics to be cleared by writing anything to
/sys/.../cpufreq/stats/reset.
Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Document restriction on per core P-State control.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PID tuning is not available when the get_target_pstate_use_cpu_load()
is used to calculate target_state. So update the documentation.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq-stats code can no longer be built as a module, so it now
appears with square brackets in menuconfig.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 1aefc75b24 (cpufreq: stats: Make the stats code non-modular)
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This reverts commit 790d849bf8.
Using a v4.7-rc7 kernel on a HP ProLiant triggered following messages
pcc-cpufreq: (v1.10.00) driver loaded with frequency limits: 1200 MHz, 2800 MHz
cpufreq: ondemand governor failed, too long transition latency of HW, fallback to performance governor
The last line was shown for each CPU in the system.
Testing v4.5 (where commit 790d849b was integrated) triggered
similar messages. Same behaviour on a 2nd HP Proliant system.
So commit 790d849bf (cpufreq: pcc-cpufreq: update default value of
cpuinfo_transition_latency) causes the system to use performance
governor which, I guess, was not the intention of the patch.
Enabling debug output in pcc-cpufreq provides following verbose output:
pcc-cpufreq: (v1.10.00) driver loaded with frequency limits: 1200 MHz, 2800 MHz
pcc_get_offset: for CPU 0: pcc_cpu_data input_offset: 0x44, pcc_cpu_data output_offset: 0x48
init: policy->max is 2800000, policy->min is 1200000
get: get_freq for CPU 0
get: SUCCESS: (virtual) output_offset for cpu 0 is 0xffffc9000d7c0048, contains a value of: 0xff06. Speed is: 168000 MHz
cpufreq: ondemand governor failed, too long transition latency of HW, fallback to performance governor
target: CPU 0 should go to target freq: 2800000 (virtual) input_offset is 0xffffc9000d7c0044
target: was SUCCESSFUL for cpu 0
I am asking to revert 790d849bf to re-enable usage of ondemand
governor with pcc-cpufreq.
Fixes: 790d849bf (cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency)
CC: <stable@vger.kernel.org> # 4.5+
Signed-off-by: Andreas Herrmann <aherrmann@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This routine can't fail unless the frequency table is invalid and
doesn't contain any valid entries.
Make it return the index and WARN() in case it is used for an invalid
table.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The policy already has this pointer set, use it instead.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
All cpufreq drivers with a freq-table are migrated to use
cpufreq_table_validate_and_show() long back and the routine
cpufreq_frequency_table_cpuinfo() isn't used outside of cpufreq core
now.
Unexport it and update Documentation as well.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This just swaps a colon for a quote in the intel_pstate documentation.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This is an attempt to make documentation more user friendly.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Doug Smythies <dsmythies@telus.net>
Reviewed-by: Chen, Yu C <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq documentation specifies
policy->cpuinfo.transition_latency the time it takes on this CPU to
switch between two frequencies in
nanoseconds (if appropriate, else
specify CPUFREQ_ETERNAL)
currently pcc-cpufreq does not expose the value and sets it to zero. I
changed the pcc-cpufreq driver and it's documentation to conform to the
default value specified in Documentation/cpu-freq/cpu-drivers.txt
Signed-off-by: Jacob Tanenbaum <jtanenba@redhat.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
What's being done from CPUFREQ_INCOMPATIBLE, can also be done with
CPUFREQ_ADJUST. There is nothing special with CPUFREQ_INCOMPATIBLE
notifier.
Kill CPUFREQ_INCOMPATIBLE and fix its usage sites.
This also updates the numbering of notifier events to remove holes.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The main thing here is Ingo's big subdirectory documenting feature support
for each architecture. Beyond that, it's the usual pile of fixes, tweaks,
and small additions.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=ODt8
-----END PGP SIGNATURE-----
Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6
Pull documentation updates from Jonathan Corbet:
"The main thing here is Ingo's big subdirectory documenting feature
support for each architecture. Beyond that, it's the usual pile of
fixes, tweaks, and small additions"
* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits)
doc:md: fix typo in md.txt.
Documentation/mic/mpssd: don't build x86 userspace when cross compiling
Documentation/prctl: don't build tsc tests when cross compiling
Documentation/vDSO: don't build tests when cross compiling
Doc:ABI/testing: Fix typo in sysfs-bus-fcoe
Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl
Doc: Change wikipedia's URL from http to https
Documentation/kernel-parameters: add missing pciserial to the earlyprintk
Doc:pps: Fix typo in pps.txt
kbuild : Fix documentation of INSTALL_HDR_PATH
Documentation: filesystems: updated struct file_operations documentation in vfs.txt
kbuild: edit explanation of clean-files variable
Doc: ja_JP: Fix typo in HOWTO
Move freefall program from Documentation/ to tools/
Documentation: ARM: EXYNOS: Describe boot loaders interface
Doc:nfc: Fix typo in nfc-hci.txt
vfs: Minor documentation fix
Doc: networking: txtimestamp: fix printf format warning
Documentation, intel_pstate: Improve legacy mode internal governors description
Documentation: extend use case for EXPORT_SYMBOL_GPL()
...
The current documentation is incomplete wrt the intel_pstate legacy
internal governors. The confusion comes from the general cpufreq
governors which also use the names performance and powersave. This patch
better differentiates between the two sets of governors and gives an
explanation of how the internal P-state governors behave differently from
one another.
Also fix two minor typos.
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: Dirk Brandewie <dirk.j.brandewie@intel.com>
Cc: x86@kernel.org
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The file 'Documentation/cpu-freq/user-guide.txt' has duplicate
description of sysfs interface 'scaling_driver'.
[first]
scaling_driver : this file shows what cpufreq driver is
used to set the frequency on this CPU
[second]
scaling_driver : Hardware driver for cpufreq.
Although this does not affect anything, I think we should only have
one. so delete the second one because the first one is described in
more detail.
Signed-off-by: Wang Long <long.wanglong@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add a sysfs interface to display the total number of supported
pstates. This value is independent of whether turbo has been
enabled or disabled.
Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds "turbo_pct" to the intel_pstate sysfs interface.
turbo_pct will display the percentage of the total supported
pstates that are in the turbo range. This value is independent
of whether turbo has been disabled or not.
Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add support of Hardware Managed Performance States (HWP) described in Volume 3
section 14.4 of the SDM.
With HWP enbaled intel_pstate will no longer be responsible for selecting P
states for the processor. intel_pstate will continue to register to
the cpufreq core as the scaling driver for CPUs implementing
HWP. In HWP mode intel_pstate provides three functions reporting
frequency to the cpufreq core, support for the set_policy() interface
from the core and maintaining the intel_pstate sysfs interface in
/sys/devices/system/cpu/intel_pstate. User preferences expressed via
the set_policy() interface or the sysfs interface are forwared to the
CPU via the HWP MSR interface.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Update documentation to make the interpretation of the values clearer
Link: https://bugzilla.kernel.org/show_bug.cgi?id=64251
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Douglas Anderson, recently pointed out an interesting problem due to which
udelay() was expiring earlier than it should.
While transitioning between frequencies few platforms may temporarily switch to
a stable frequency, waiting for the main PLL to stabilize.
For example: When we transition between very low frequencies on exynos, like
between 200MHz and 300MHz, we may temporarily switch to a PLL running at 800MHz.
No CPUFREQ notification is sent for that. That means there's a period of time
when we're running at 800MHz but loops_per_jiffy is calibrated at between 200MHz
and 300MHz. And so udelay behaves badly.
To get this fixed in a generic way, introduce another set of callbacks
get_intermediate() and target_intermediate(), only for drivers with
target_index() and CPUFREQ_ASYNC_NOTIFICATION unset.
get_intermediate() should return a stable intermediate frequency platform wants
to switch to, and target_intermediate() should set CPU to that frequency,
before jumping to the frequency corresponding to 'index'. Core will take care of
sending notifications and driver doesn't have to handle them in
target_intermediate() or target_index().
NOTE: ->target_index() should restore to policy->restore_freq in case of
failures as core would send notifications for that.
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CPUFreq specific helper functions for OPP (Operating Performance Points)
now use generic OPP functions that allow CPUFreq to be be moved back
into CPUFreq framework. This allows for independent modifications
or future enhancements as needed isolated to just CPUFreq framework
alone.
Here, we just move relevant code and documentation to make this part of
CPUFreq infrastructure.
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There has been confusion all the time about which mailing list to follow
for cpufreq activities, linux-pm@vger.kernel.org or cpufreq@vger.kernel.org.
Since patches sent to cpufreq@vger.kernel.org don't go to Patchwork
which is a maintenance workflow problem, make linux-pm@vger.kernel.org
the official mailing list for cpufreq stuff and remove all references
of cpufreq@vger.kernel.org from kernel source.
Later, we can request that the list be dropped entirely.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Many cpufreq drivers need to iterate over the cpufreq_frequency_table
for various tasks.
This patch introduces two macros which can be used for iteration over
cpufreq_frequency_table keeping a common coding style across drivers:
- cpufreq_for_each_entry: iterate over each entry of the table
- cpufreq_for_each_valid_entry: iterate over each entry that contains
a valid frequency.
It should have no functional changes.
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This callback allows the driver to do clean up before the CPU is
completely down and its state cannot be modified. This is used
by the intel_pstate driver to reduce the requested P state prior to
the core going away. This is required because the requested P state
of the offline core is used to select the package P state. This
effectively sets the floor package P state to the requested P state on
the offline core.
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
[rjw: Minor modifications]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Two cpufreq notifiers CPUFREQ_RESUMECHANGE and CPUFREQ_SUSPENDCHANGE have
not been used for some time, so remove them to clean up code a bit.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tang Yizhou
Viresh Kumar
Mauro Carvalho Chehab
Rafael J. Wysocki
Mauro Carvalho Chehab
Dominik Brodowski
Gautham R. Shenoy
Rafael J. Wysocki
sayli karnik
Linus Torvalds
Shilpasri G Bhat
Srinivas Pandruvada
Markus Mayer
Jean Delvare
Andreas Herrmann
Felipe Franciosi
Jacob Tanenbaum
Prarit Bhargava
Wang Long
Kristen Carlson Accardi
Dirk Brandewie
Nishanth Menon
Stratos Karafotis