cpufreq: dt: always allocate zeroed cpumask

Commit 0499a78369ad ("ARM64: Dynamically allocate cpumasks and increase
supported CPUs to 512") changed the handling of cpumasks on ARM 64bit,
what resulted in the strange issues and warnings during cpufreq-dt
initialization on some big.LITTLE platforms.

This was caused by mixing OPPs between big and LITTLE cores, because
OPP-sharing information between big and LITTLE cores is computed on
cpumask, which in turn was not zeroed on allocation. Fix this by
switching to zalloc_cpumask_var() call.

Fixes: dc279ac6e5b4 ("cpufreq: dt: Refactor initialization to handle probe deferral properly")
CC: stable@vger.kernel.org # v5.10+
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: dt: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: dt: Switch to use dev_err_probe() helper

In the probe path, dev_err() can be replaced with dev_err_probe()
which will check if error code is -EPROBE_DEFER and prints the
error name. It also sets the defer probe reason which can be
checked later through debugfs. It's more simple in error path.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

OPP: Migrate set-regulators API to use set-config helpers

Now that we have a central API to handle all OPP table configurations,
migrate the set-regulators family of helpers to use the new
infrastructure.

The return type and parameter to the APIs change a bit due to this,
update the current users as well in the same commit in order to avoid
breaking builds.

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

OPP: Make dev_pm_opp_set_regulators() accept NULL terminated list

Make dev_pm_opp_set_regulators() accept a NULL terminated list of names
instead of making the callers keep the two parameters in sync, which
creates an opportunity for bugs to get in.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Steven Price <steven.price@arm.com> # panfrost
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: dt: Use .register_em() to register with energy model

Set the newly added .register_em() callback with
cpufreq_register_em_with_opp() to register with the EM core.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: dt: dev_pm_opp_of_cpumask_add_table() may return -EPROBE_DEFER

The function dev_pm_opp_of_cpumask_add_table() may return -EPROBE_DEFER,
which needs to be propagated to the caller to try probing the driver
later on.

Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
[ Viresh: Massage changelog/subject, improve code. ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: Remove CPUFREQ_STICKY flag

During cpufreq driver's registration, if the ->init() callback for all
the CPUs fail then there is not much point in keeping the driver around
as it will only account for more of unnecessary noise, for example
cpufreq core will try to suspend/resume the driver which never got
registered properly.

The removal of such a driver is avoided if the driver carries the
CPUFREQ_STICKY flag. This was added way back [1] in 2004 and perhaps no
one should ever need it now. A lot of drivers do set this flag, probably
because they just copied it from other drivers.

This was added earlier for some platforms [2] because their cpufreq
drivers were getting registered before the CPUs were registered with
subsys framework. And hence they used to fail.

The same isn't true anymore though. The current code flow in the kernel
is:

start_kernel()
-> kernel_init()
-> kernel_init_freeable()
-> do_basic_setup()
-> driver_init()
-> cpu_dev_init()
-> subsys_system_register() //For CPUs

-> do_initcalls()
-> cpufreq_register_driver()

Clearly, the CPUs will always get registered with subsys framework
before any cpufreq driver can get probed. Remove the flag and update the
relevant drivers.

Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/include/linux/cpufreq.h?id=7cc9f0d9a1ab04cedc60d64fd8dcf7df224a3b4d # [1]
Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/arch/arm/mach-sa1100/cpu-sa1100.c?id=f59d3bbe35f6268d729f51be82af8325d62f20f5 # [2]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: dev_pm_opp_put_regulators() accepts NULL argument

The dev_pm_opp_put_*() APIs now accepts a NULL opp_table pointer and so
there is no need for us to carry the extra checks. Drop them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: dt: Don't (ab)use dev_pm_opp_get_opp_table() to create OPP table

Initially, the helper dev_pm_opp_get_opp_table() was supposed to be used
only for the OPP core's internal use (it tries to find an existing OPP
table and if it doesn't find one, then it allocates the OPP table).

Sometime back, the cpufreq-dt driver started using it to make sure all
the relevant resources required by the OPP core are available earlier
during initialization process to properly propagate -EPROBE_DEFER.

It worked but it also abused the API to create an OPP table, which
should be created with the help of other helpers provided by the OPP
core.

The OPP core will be updated in a later commit to limit the scope of
dev_pm_opp_get_opp_table() to only finding an existing OPP table and not
create one. This commit updates the cpufreq-dt driver before that
happens.

Now the cpufreq-dt driver creates the OPP and cpufreq tables for all the
CPUs from driver's init callback itself.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: move invariance setter calls in cpufreq core

To properly scale its per-entity load-tracking signals, the task scheduler
needs to be given a frequency scale factor, i.e. some image of the current
frequency the CPU is running at. Currently, this scale can be computed
either by using counters (APERF/MPERF on x86, AMU on arm64), or by
piggy-backing on the frequency selection done by cpufreq.

For the latter, drivers have to explicitly set the scale factor
themselves, despite it being purely boiler-plate code: the required
information depends entirely on the kind of frequency switch callback
implemented by the driver, i.e. either of: target_index(), target(),
fast_switch() and setpolicy().

The fitness of those callbacks with regard to driving the Frequency
Invariance Engine (FIE) is studied below:

target_index()
==============
Documentation states that the chosen frequency "must be determined by
freq_table[index].frequency". It isn't clear if it *has* to be that
frequency, or if it can use that frequency value to do some computation
that ultimately leads to a different frequency selection. All drivers
go for the former, while the vexpress-spc-cpufreq has an atypical
implementation which is handled separately.

Therefore, the hook works on the assumption the core can use
freq_table[index].frequency.

target()
=======
This has been flagged as deprecated since:

commit 9c0ebcf78fde ("cpufreq: Implement light weight ->target_index() routine")

It also doesn't have that many users:

gx-suspmod.c:439: .target = cpufreq_gx_target,
s3c24xx-cpufreq.c:428: .target = s3c_cpufreq_target,
intel_pstate.c:2528: .target = intel_cpufreq_target,
cppc_cpufreq.c:401: .target = cppc_cpufreq_set_target,
cpufreq-nforce2.c:371: .target = nforce2_target,
sh-cpufreq.c:163: .target = sh_cpufreq_target,
pcc-cpufreq.c:573: .target = pcc_cpufreq_target,

Similarly to the path taken for target_index() calls in the cpufreq core
during a frequency change, all of the drivers above will mark the end of a
frequency change by a call to cpufreq_freq_transition_end().

Therefore, cpufreq_freq_transition_end() can be used as the location for
the arch_set_freq_scale() call to potentially inform the scheduler of the
frequency change.

This change maintains the previous functionality for the drivers that
implement the target_index() callback, while also adding support for the
few drivers that implement the deprecated target() callback.

fast_switch()
=============
This callback *has* to return the frequency that was selected.

setpolicy()
===========
This callback does not have any designated way of informing what was the
end choice. But there are only two drivers using setpolicy(), and none
of them have current FIE support:

drivers/cpufreq/longrun.c:281: .setpolicy = longrun_set_policy,
drivers/cpufreq/intel_pstate.c:2215: .setpolicy = intel_pstate_set_policy,

The intel_pstate is known to use counter-driven frequency invariance.

Conclusion
==========

Given that the significant majority of current FIE enabled drivers use
callbacks that lend themselves to triggering the setting of the FIE scale
factor in a generic way, move the invariance setter calls to cpufreq core.

As a result of setting the frequency scale factor in cpufreq core, after
callbacks that lend themselves to trigger it, remove this functionality
from the driver side.

To be noted that despite marking a successful frequency change, many
cpufreq drivers will consider the new frequency as the requested
frequency, although this is might not be the one granted by the hardware.

Therefore, the call to arch_set_freq_scale() is a "best effort" one, and
it is up to the architecture if the new frequency is used in the new
frequency scale factor setting (determined by the implementation of
arch_set_freq_scale()) or eventually used by the scheduler (determined
by the implementation of arch_scale_freq_capacity()). The architecture
is in a better position to decide if it has better methods to obtain
more accurate information regarding the current frequency and use that
information instead (for example, the use of counters).

Also, the implementation to arch_set_freq_scale() will now have to handle
error conditions (current frequency == 0) in order to prevent the
overhead in cpufreq core when the default arch_set_freq_scale()
implementation is used.

Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Suggested-by: Valentin Schneider <valentin.schneider@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Refactor initialization to handle probe deferral properly

cpufreq-dt is currently unable to handle -EPROBE_DEFER properly
because the error code is not propagated for the cpufreq_driver->init()
callback. Instead, it attempts to avoid the situation by temporarily
requesting all resources within resources_available() and releasing them
again immediately after. This has several disadvantages:

- Whenever we add something like interconnect handling to the OPP core
we need to patch cpufreq-dt to request these resources early.

- resources_available() is only run for CPU0, but other clusters may
eventually depend on other resources that are not available yet.
(See FIXME comment removed by this commit...)

- All resources need to be looked up several times.

Now that the OPP core can propagate -EPROBE_DEFER during initialization,
it would be nice to avoid all that trouble and just propagate its error
code when necessary.

This commit refactors the cpufreq-dt driver to initialize private_data
before registering the cpufreq driver. We do this by iterating over
all possible CPUs and ensure that all resources are initialized:

1. dev_pm_opp_get_opp_table() ensures the OPP table is allocated
and initialized with clock and interconnects.

2. dev_pm_opp_set_regulators() requests the regulators and assigns
them to the OPP table.

3. We call dev_pm_opp_of_get_sharing_cpus() early so that we only
initialize the OPP table once for each shared policy.

With these changes, we actually end up saving a few lines of code,
the resources are no longer looked up multiple times and everything
should be much more robust.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
[ Viresh: Use list_head structure for maintaining the list and minor
changes ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

OPP: refactor dev_pm_opp_of_register_em() and update related drivers

The Energy Model framework supports not only CPU devices. Drop the CPU
specific interface with cpumask and add struct device. Add also a return
value, user might use it. This new interface provides easy way to create
a simple Energy Model, which then might be used by e.g. thermal subsystem.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Add support for interconnect bandwidth scaling

In addition to clocks and regulators, some devices can scale the bandwidth
of their on-chip interconnect - for example between CPU and DDR memory. Add
support for that, so that platforms which support it can make use of it.

Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
[ Viresh: Reused dev_pm_opp_of_find_icc_paths(). Also drop the depends
on from Kconfig. ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

fixup! cpufreq: dt: Add support for interconnect bandwidth scaling

cpufreq: dt: Allow platform specific intermediate callbacks

Platforms may need to implement platform specific get_intermediate and
target_intermediate hooks.

Update cpufreq-dt driver's platform data to contain those for such
platforms.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

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 <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cpufreq: dt: Implement online/offline() callbacks

Implement the light-weight tear down and bring up helpers to reduce the
amount of work to do on CPU offline/online operation.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Register an Energy Model

Now that PM_OPP provides a helper function to estimate the power
consumed by CPUs, make sure to try and register an Energy Model (EM)
from cpufreq-dt, hence ensuring interested subsystems (the task
scheduler, for example) can make use of that information when available.

Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: cpufreq-dt: Use auto-registration of thermal cooling device

Use the CPUFREQ_IS_COOLING_DEV flag to allow cpufreq core to
automatically register as a thermal cooling device.

This allows removal of boiler plate code from the driver.

Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Try freeing static OPPs only if we have added them

We can not call dev_pm_opp_of_cpumask_remove_table() freely anymore
since the latest OPP core updates as that uses reference counting to
free resources. There are cases where no static OPPs are added (using
DT) for a platform and trying to remove the OPP table may end up
decrementing refcount which is already zero and hence generating
warnings.

Lets track if we were able to add static OPPs or not and then only
remove the table based on that. Some reshuffling of code is also done to
do that.

Reported-by: Niklas Cassel <niklas.cassel@linaro.org>
Tested-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

cpufreq: dt: Allow platform specific suspend/resume callbacks

Platforms may need to implement platform specific suspend/resume hooks.
Update cpufreq-dt driver's platform data to contain those for such
platforms.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: Don't validate the frequency table twice

The cpufreq core is already validating the CPU frequency table after
calling the ->init() callback of the cpufreq drivers and the drivers
don't need to do the same anymore. Though they need to set the
policy->freq_table field directly from the ->init() callback now.

Stop validating the frequency table from cpufreq-dt driver.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpu_cooling: Keep only one of_cpufreq*cooling_register() helper

of_cpufreq_cooling_register() isn't used by anyone and so can be
removed, but then we would be left with two routines:
cpufreq_cooling_register() and of_cpufreq_power_cooling_register() that
would look odd.

Remove current implementation of of_cpufreq_cooling_register() and
rename of_cpufreq_power_cooling_register() as
of_cpufreq_cooling_register(). This simplifies lots of stuff.

Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpu_cooling: Make of_cpufreq_power_cooling_register() parse DT

All the callers of of_cpufreq_power_cooling_register() have almost
identical code and it makes more sense to move that code into the helper
as its all about reading DT properties.

This got rid of lot of redundant code.

Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: invoke frequency-invariance setter function

Call the frequency-invariance setter function arch_set_freq_scale()
if the new frequency has been successfully set which is indicated by
dev_pm_opp_set_rate() returning 0.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: Process remote callbacks from any CPU if the platform permits

On many platforms, CPUs can do DVFS across cpufreq policies. i.e CPU
from policy-A can change frequency of CPUs belonging to policy-B.

This is quite common in case of ARM platforms where we don't
configure any per-cpu register.

Add a flag to identify such platforms and update
cpufreq_can_do_remote_dvfs() to allow remote callbacks if this flag is
set.

Also enable the flag for cpufreq-dt driver which is used only on ARM
platforms currently.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

thermal: cpu_cooling: use cpufreq_policy to register cooling device

The CPU cooling driver uses the cpufreq policy, to get clip_cpus, the
frequency table, etc. Most of the callers of CPU cooling driver's
registration routines have the cpufreq policy with them, but they only
pass the policy->related_cpus cpumask. The __cpufreq_cooling_register()
routine then gets the policy by itself and uses it.

It would be much better if the callers can pass the policy instead
directly. This also fixes a basic design flaw, where the policy can be
freed while the CPU cooling driver is still active.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

PM / OPP: Rename dev_pm_opp_get_suspend_opp() and return OPP rate

There is only one user of dev_pm_opp_get_suspend_opp() and that uses it
to get the OPP rate for the suspend_opp.

Rename dev_pm_opp_get_suspend_opp() as dev_pm_opp_get_suspend_opp_freq()
and return the rate directly from it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / OPP: Add infrastructure to manage multiple regulators

This patch adds infrastructure to manage multiple regulators and updates
the only user (cpufreq-dt) of dev_pm_opp_set{put}_regulator().

This is preparatory work for adding full support for devices with
multiple regulators.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / OPP: Pass opp_table to dev_pm_opp_put_regulator()

Joonyoung Shim reported an interesting problem on his ARM octa-core
Odoroid-XU3 platform. During system suspend, dev_pm_opp_put_regulator()
was failing for a struct device for which dev_pm_opp_set_regulator() is
called earlier.

This happened because an earlier call to
dev_pm_opp_of_cpumask_remove_table() function (from cpufreq-dt.c file)
removed all the entries from opp_table->dev_list apart from the last CPU
device in the cpumask of CPUs sharing the OPP.

But both dev_pm_opp_set_regulator() and dev_pm_opp_put_regulator()
routines get CPU device for the first CPU in the cpumask. And so the OPP
core failed to find the OPP table for the struct device.

This patch attempts to fix this problem by returning a pointer to the
opp_table from dev_pm_opp_set_regulator() and using that as the
parameter to dev_pm_opp_put_regulator(). This ensures that the
dev_pm_opp_put_regulator() doesn't fail to find the opp table.

Note that similar design problem also exists with other
dev_pm_opp_put_*() APIs, but those aren't used currently by anyone and
so we don't need to update them for now.

Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Reported-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ Viresh: Wrote commit log and tested on exynos 5250 ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Support governor tunables per policy

The cpufreq-dt driver is also used for systems with multiple
clock/voltage domains for CPUs, i.e. multiple cpufreq policies in a
system.

And in such cases the platform users may want to enable "governor
tunables per policy". Support that via platform data, as not all users
of the driver would want that behavior.

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>

cpufreq: dt: Remove unused code

This is leftover from an earlier patch which removed the usage of
platform data but forgot to remove this line. Remove it now.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Kill platform-data

There are no more users of platform-data for cpufreq-dt driver, get rid
of it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Identify cpu-sharing for platforms without operating-points-v2

Existing platforms, which do not support operating-points-v2, can
explicitly tell the opp core that some of the CPUs share opp tables,
with help of dev_pm_opp_set_sharing_cpus().

For such platforms, explicitly ask the opp core to provide list of CPUs
sharing the opp table with current cpu device, before falling back to
platform data.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Drop stale comment

The comment in file header doesn't hold true anymore, drop it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: No need to allocate resources anymore

OPP layer manages it now and cpufreq-dt driver doesn't need it. But, we
still need to check for availability of resources for deferred probing.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: No need to fetch voltage-tolerance

Its already done by core and we don't need to get it anymore. And so,
we don't need to get of node in cpufreq_init() anymore, move that to
find_supply_name() instead.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Use dev_pm_opp_set_rate() to switch frequency

OPP core supports frequency/voltage changes based on the target
frequency now, use that instead of open coding the same in cpufreq-dt
driver.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Reuse dev_pm_opp_get_max_transition_latency()

OPP layer has all the information now to calculate transition latency
(clock_latency + voltage_latency). Lets reuse the OPP layer helper
dev_pm_opp_get_max_transition_latency() instead of open coding the same
in cpufreq-dt driver.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Unsupported OPPs are already disabled

The core already have a valid regulator set for the device opp and the
unsupported OPPs are already disabled by the core. There is no need to
repeat that in the user drivers, get rid of it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Pass regulator name to the OPP core

OPP core can handle the regulators by itself, and but it needs to know
the name of the regulator to fetch. Add support for that.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: OPP layers handles clock-latency for V1 bindings as well

"clock-latency" is handled by OPP layer for all bindings and so there is
no need to make special calls for V1 bindings. Use
dev_pm_opp_get_max_clock_latency() for both the cases.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Rename 'need_update' to 'opp_v1'

That's the real purpose of this field, i.e. to take special care of old
OPP V1 bindings. Lets name it accordingly, so that it can be used
elsewhere.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Convert few pr_debug/err() calls to dev_dbg/err()

We have the device structure available now, lets use it for better print
messages.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: avoid uninitialized variable warnings:

gcc warns quite a bit about values returned from allocate_resources()
in cpufreq-dt.c:

cpufreq-dt.c: In function 'cpufreq_init':
cpufreq-dt.c:327:6: error: 'cpu_dev' may be used uninitialized in this function [-Werror=maybe-uninitialized]
cpufreq-dt.c:197:17: note: 'cpu_dev' was declared here
cpufreq-dt.c:376:2: error: 'cpu_clk' may be used uninitialized in this function [-Werror=maybe-uninitialized]
cpufreq-dt.c:199:14: note: 'cpu_clk' was declared here
cpufreq-dt.c: In function 'dt_cpufreq_probe':
cpufreq-dt.c:461:2: error: 'cpu_clk' may be used uninitialized in this function [-Werror=maybe-uninitialized]
cpufreq-dt.c:447:14: note: 'cpu_clk' was declared here

The problem is that it's slightly hard for gcc to follow return
codes across PTR_ERR() calls.

This patch uses explicit assignments to the "ret" variable to make
it easier for gcc to verify that the code is actually correct,
without the need to add a bogus initialization.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: fix handling regulator_get_voltage() result

The function can return negative values so it should be assigned
to signed type.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci.

Link: http://permalink.gmane.org/gmane.linux.kernel/2038576
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: Supply power coefficient when registering cooling devices

Support registering cooling devices with dynamic power coefficient
where provided by the device tree. This allows OF registered cooling
devices driver to be used with the power_allocator thermal governor.

Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / OPP: Prefix exported opp routines with dev_pm_opp_

That's the naming convention followed in most of opp core, but few
routines didn't follow this, fix them.

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / OPP: Rename opp init/free table routines

free-table routines are opposite of init-table ones, and must be named
to make that clear. Opposite of 'init' is 'exit', but those doesn't suit
really well.

Replace 'init' with 'add' and 'free' with 'remove'.

Reported-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: add suspend frequency support

Add suspend frequency support and if needed set it to
the frequency obtained from the suspend opp (can be defined
using opp-v2 bindings and is optional).

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Tolerance applies on both sides of target voltage

Tolerance applies on both sides of the target voltage, i.e. both min and
max sides. But while checking if a voltage is supported by the regulator
or not, we haven't taken care of tolerance on the lower side. Fix that.

Cc: Lucas Stach <l.stach@pengutronix.de>
Fixes: 045ee45c4ff2 ("cpufreq: cpufreq-dt: disable unsupported OPPs")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Print error on failing to mark OPPs as shared

We need to explicitly mark OPPs as shared, when they are not defined
with OPP-v2 bindings. This operation can potentially fail, and in that
case we should at least print an error message.

Fixes: 2e02d8723edf ("cpufreq: dt: Add support for operating-points-v2 bindings")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Check OPP count before marking them shared

We need to explicitly mark OPPs as shared, when they are not defined
with OPP-v2 bindings. But this isn't required to be done if we failed to
initialize OPP table.

Reorder code to verify OPP count before marking them shared.

Fixes: 2e02d8723edf ("cpufreq: dt: Add support for operating-points-v2 bindings")
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: make scaling_boost_freqs sysfs attr available when boost is enabled

Make scaling_boost_freqs sysfs attribute is available when
cpufreq-dt driver is used and boost support is enabled.

Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Add support for turbo/boost mode

With opp-v2 DT bindings, few OPPs can be used only for the boost mode.
But using such OPPs require the boost mode to be supported by cpufreq
driver.

We will parse DT bindings only during ->init() and so can enable boost
support only after registering cpufreq driver.

This enables boost support as soon as any policy has boost/turbo OPPs
for its CPUs.

We don't need to disable boost support as that is done by the core, when
the driver is unregistered.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: Add support for operating-points-v2 bindings

Support for parsing operating-points-v2 bindings is in place now, lets
modify cpufreq-dt driver to use them.

For backward compatibility we will continue to support earlier bindings.
Special handling for that is required, to make sure OPPs are initialized
for all the CPUs.

Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: dt: allow driver to boot automatically

by adding the missing MODULE_ALIAS(), cpufreq-dt
can be autoloaded by udev/systemd.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Acked-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>

cpufreq-dt: Drop unnecessary check before cpufreq_cooling_unregister() invocation

The cpufreq_cooling_unregister() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: defer probing if OPP table is not ready

cpufreq-dt driver supports mode when OPP table is provided by platform
code and not device tree. However on certain platforms code that fills
OPP table may run after cpufreq driver tries to initialize, so let's
report -EPROBE_DEFER if we do not find any entires in OPP table for the
CPU.

Signed-off-by: Dmitry Torokhov <dtor@chromium.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: free OPP table created during ->init()

OPP layer now supports freeing of OPPs and we should free them once they aren't
useful anymore.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: register cooling device from ->ready() callback

Currently we are calling of_cpufreq_cooling_register() from ->init() callback.
At this point of time cpufreq driver's policy isn't completely ready to be used
as few of its fields/structure/pointers aren't yet initialized.

Because of_cpufreq_cooling_register() tries to access policy with help of
cpufreq_cpu_get() and then tries to get freq-table as well, these calls fail.

To fix this, register the cooling device after the policy is ready to be used.
And the right callback for it is the newly added ->ready() one.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Eduardo Valentin <edubezval@gmail.com>
Tested-by: Eduardo Valentin <edubezval@gmail.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq-dt: pass 'policy->related_cpus' to of_cpufreq_cooling_register()

The second parameter of of_cpufreq_cooling_register() should be the CPUs to
which the frequency constraint will apply. As the cpufreq-dt driver now supports
platforms with multiple 'struct cpufreq_policy' instances (i.e. > 1 clock
domains for CPUs), passing 'cpu_present_mask' isn't correct anymore. As every
policy will have a set of CPUs and that may not be equal to 'cpu_present_mask'
always.

So, pass only mask of CPUs which are controlled by current policy.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Eduardo Valentin <edubezval@gmail.com>
Tested-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: Move newline to end of error message

Currently the error message is needlessly splitted across two lines.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

cpufreq: cpufreq-dt: Handle regulator_get_voltage() failure

In error cases regulator_get_voltage() returns a negative value.
So take care of it.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: Improve debug about matching OPP

During test of new DT OPPs it's very helpful to print the matching
OPP in case of frequency change. So it will be easier to find frequency
rounding issues in the dts file.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: Fix arguments in clock failure error message

Fix the swapped arguments in the clock failure dev_err.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: Restore default cpumask_setall(policy->cpus)

Commit 34e5a5273d6aa0ee ("cpufreq: cpufreq-dt: extend with
platform_data") changed cpufreq_init() to only call
cpumask_setall(policy->cpus) if the platform data indicates that all
CPUs share the same clock. Before, cpufreq_generic_init() did this
unconditionally.

This causes a crash on r8a7791/koelsch when resuming from s2ram:

Enabling non-boot CPUs ...
CPU1: Booted secondary processor
Unable to handle kernel NULL pointer dereference at virtual address 0000003c
pgd = ee71f980
[0000003c] *pgd=6eeb6003, *pmd=6e0e9003, *pte=00000000
Internal error: Oops: a07 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1397 Comm: s2ram Tainted: G W 3.18.0-rc2-koelsch-00762-g7eed2a4e61d2d978 #581
task: ee6b76c0 ti: ee7f0000 task.ti: ee7f0000
PC is at __cpufreq_add_dev.isra.24+0x24c/0x77c
LR is at __cpufreq_add_dev.isra.24+0x244/0x77c
pc : [<c029e084>] lr : [<c029e07c>] psr: 60000153
sp : ee7f1d48 ip : ee7f1d48 fp : ee7f1d84
r10: c04e8448 r9 : 00000000 r8 : 00000001
r7 : c054a8c4 r6 : 00000001 r5 : 00000001 r4 : 00000000
r3 : 00000000 r2 : 00000000 r1 : 20000153 r0 : c054a950
Flags: nZCv IRQs on FIQs off Mode SVC_32 ISA ARM Segment user
Control: 30c5307d Table: 6e71f980 DAC: fffffffd
Process s2ram (pid: 1397, stack limit = 0xee7f0240)

...

Backtrace:
[<c029de38>] (__cpufreq_add_dev.isra.24) from [<c029e620>] (cpufreq_cpu_callback+0x6c/0x74)
r10:eec75240 r9:c04e8448 r8:c04ef3a0 r7:00000001 r6:00000012 r5:00000000
r4:00000012
[<c029e5b4>] (cpufreq_cpu_callback) from [<c003f20c>] (notifier_call_chain+0x48/0x70)
r4:ffffffdd r3:c029e5b4
[<c003f1c4>] (notifier_call_chain) from [<c003f2cc>] (__raw_notifier_call_chain+0x1c/0x24)
r8:00000001 r7:00000010 r6:00000000 r5:00000000 r4:00000012 r3:ffffffff
[<c003f2b0>] (__raw_notifier_call_chain) from [<c0026a00>] (__cpu_notify+0x34/0x50)
[<c00269cc>] (__cpu_notify) from [<c0026a34>] (cpu_notify+0x18/0x1c)
r4:00000001
[<c0026a1c>] (cpu_notify) from [<c0026c44>] (_cpu_up+0x108/0x144)
[<c0026b3c>] (_cpu_up) from [<c0381c68>] (enable_nonboot_cpus+0x68/0xb8)
r10:00000000 r9:c04e8ee6 r8:00000000 r7:00000003 r6:c04e8528 r5:c0506248
r4:00000001
[<c0381c00>] (enable_nonboot_cpus) from [<c0059038>] (suspend_devices_and_enter+0x29c/0x3e8)
r6:c0506e70 r5:00000000 r4:00000000 r3:60000153

Restore the old default of calling cpumask_setall(policy->cpus) if no
platform data is available to fix this.

Fixes: 34e5a5273d6aa0ee (cpufreq: cpufreq-dt: extend with platform_data)
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: disable unsupported OPPs

If the regulator connected to the CPU voltage plane doesn't
support an OPP specified voltage with the acceptable tolerance
it's better to just disable the OPP instead of constantly
failing the voltage scaling later on.

Includes a fix to move initialization of opp_freq outside
the loop to avoid an endless loop from Geert Uytterhoeven.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: adjust message related to regulators

The cpufreq-dt driver tries to get a regulator for each CPU. This
regulator is optional, but when not present, a scary message "failed
to get cpuX regulator" is displayed. To solve this, we reduce the
severity of the message from dev_warn() to dev_dbg() and we reword the
message to not be as scary.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: cpufreq-dt: extend with platform_data

This commit extends the cpufreq-dt driver to take a platform_data
structure. This structure is for now used to tell the cpufreq-dt
driver the layout of the clocks on the platform, i.e whether all CPUs
share the same clock or whether each CPU has a separate clock.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq: drop owner assignment from platform_drivers

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

cpufreq: cpufreq-dt: fix potential double put of cpu OF node

If cpufreq_generic_init() fails we jump into the resource
cleanup path which contains a of_node_put() call. Another
instance of this has already been called at that time
resulting a double decrement of the refcount.

Fix this by calling of_node_put() only after we are sure
that nothing has gone wrong.

Fixes: d2f31f1da54f "cpufreq: cpu0: Move per-cluster initialization code to ->init()"
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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>