Commit Graph

82 Commits

Author SHA1 Message Date
Andrzej Hajda 8cc311167c PM / OPP: fix off-by-one bug in dev_pm_opp_get_max_volt_latency loop
Reading array at given index before checking if index is valid results in
illegal memory access.

The bug was detected using KASAN framework.

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>
2017-02-23 23:00:31 +01:00
Dave Gerlach 0764c604c8 PM / OPP: Expose _of_get_opp_desc_node as dev_pm_opp API
Rename _of_get_opp_desc_node to dev_pm_opp_of_get_opp_desc_node and add it
to include/linux/pm_opp.h to allow other drivers, such as platform OPP
and cpufreq drivers, to make use of it.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-09 22:52:17 +01:00
Wei Yongjun 6ac4239733 PM / OPP: Make _find_opp_table_unlocked() static
Fixes the following sparse warning:

drivers/base/power/opp/core.c:49:18: warning:
 symbol '_find_opp_table_unlocked' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-07 13:39:25 +01:00
Viresh Kumar cdd3e614cf PM / OPP: Simplify dev_pm_opp_get_max_volt_latency()
dev_pm_opp_get_max_volt_latency() calls _find_opp_table() two times
effectively.

Merge _get_regulator_count() into dev_pm_opp_get_max_volt_latency() to
avoid 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>
2017-01-30 09:22:22 +01:00
Viresh Kumar a7f3987ea1 PM / OPP: Simplify _opp_set_availability()
As we don't use RCU locking anymore, there is no need to replace an
earlier OPP node with a new one. Just update the existing one.

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>
2017-01-30 09:22:22 +01:00
Viresh Kumar 052c6f1914 PM / OPP: Move away from RCU locking
The RCU locking isn't well suited for the OPP core. The RCU locking fits
better for reader heavy stuff, while the OPP core have at max one or two
readers only at a time.

Over that, it was getting very confusing the way RCU locking was used
with the OPP core. The individual OPPs are mostly well handled, i.e. for
an update a new structure was created and then that replaced the older
one. But the OPP tables were updated directly all the time from various
parts of the core. Though they were mostly used from within RCU locked
region, they didn't had much to do with RCU and were governed by the
mutex instead.

And that mixed with the 'opp_table_lock' has made the core even more
confusing.

Now that we are already managing the OPPs and the OPP tables with kernel
reference infrastructure, we can get rid of RCU locking completely and
simplify the code a lot.

Remove all RCU references from code and comments.

Acquire opp_table->lock while parsing the list of OPPs though.

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>
2017-01-30 09:22:22 +01:00
Viresh Kumar 5b650b3888 PM / OPP: Take kref from _find_opp_table()
Take reference of the OPP table from within _find_opp_table(). Also
update the callers of _find_opp_table() to call
dev_pm_opp_put_opp_table() after they have used the OPP table.

Note that _find_opp_table() increments the reference under the
opp_table_lock.

Now that the OPP table wouldn't get freed until the callers of
_find_opp_table() call dev_pm_opp_put_opp_table(), there is no need to
take the opp_table_lock or rcu_read_lock() around it. Drop them.

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>
2017-01-30 09:22:22 +01:00
Viresh Kumar 8a31d9d942 PM / OPP: Update OPP users to put reference
This patch updates dev_pm_opp_find_freq_*() routines to get a reference
to the OPPs returned by them.

Also updates the users of dev_pm_opp_find_freq_*() routines to call
dev_pm_opp_put() after they are done using the OPPs.

As it is guaranteed the that OPPs wouldn't get freed while being used,
the RCU read side locking present with the users isn't required anymore.
Drop it as well.

This patch also updates all users of devfreq_recommended_opp() which was
returning an OPP received from the OPP core.

Note that some of the OPP core routines have gained
rcu_read_{lock|unlock}() calls, as those still use RCU specific APIs
within them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> [Devfreq]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-30 09:22:21 +01:00
Viresh Kumar 7034764a1e PM / OPP: Add 'struct kref' to struct dev_pm_opp
Add kref to struct dev_pm_opp for easier accounting of the OPPs.

Note that the OPPs are freed under the opp_table->lock mutex only.

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>
2017-01-30 09:22:21 +01:00
Viresh Kumar b83c1899a0 PM / OPP: Use dev_pm_opp_get_opp_table() instead of _add_opp_table()
Migrate all users of _add_opp_table() to use dev_pm_opp_get_opp_table()
to guarantee that the OPP table doesn't get freed while being used.

Also update _managed_opp() to get the reference to the OPP table.

Now that the OPP table wouldn't get freed while these routines are
executing after dev_pm_opp_get_opp_table() is called, there is no need
to take opp_table_lock. Drop them as well.

Now that _add_opp_table(), _remove_opp_table() and the unlocked release
routines aren't used anymore, remove them.

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>
2017-01-30 09:22:21 +01:00
Viresh Kumar 31641cda53 PM / OPP: Take reference of the OPP table while adding/removing OPPs
Take reference of the OPP table while adding and removing OPPs, that
helps us remove special checks in _remove_opp_table().

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>
2017-01-30 09:22:21 +01:00
Viresh Kumar fa30184d19 PM / OPP: Return opp_table from dev_pm_opp_set_*() routines
Now that we have proper kernel reference infrastructure in place for OPP
tables, use it to guarantee that the OPP table isn't freed while being
used by the callers of dev_pm_opp_set_*() APIs.

Make them all return the pointer to the OPP table after taking its
reference and put the reference back with dev_pm_opp_put_*() APIs.

Now that the OPP table wouldn't get freed while these routines are
executing after dev_pm_opp_get_opp_table() is called, there is no need
to take opp_table_lock. Drop them as well.

Remove the rcu specific comments from these routines as they aren't
relevant anymore.

Note that prototypes of dev_pm_opp_{set|put}_regulators() were already
updated by another patch.

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>
2017-01-30 09:22:21 +01:00
Viresh Kumar f067a982ce PM / OPP: Add 'struct kref' to OPP table
Add kref to struct opp_table for easier accounting of the OPP table.

Note that the new routine dev_pm_opp_get_opp_table() takes the reference
from under the opp_table_lock, which guarantees that the OPP table
doesn't get freed unless dev_pm_opp_put_opp_table() is called for the
OPP table.

Two separate release mechanisms are added: locked and unlocked. In
unlocked version the routines aren't required to take/drop
opp_table_lock as the callers have already done that. This is required
to avoid breaking git bisect, otherwise we may get lockdeps between
commits. Once all the users of OPP table are updated the unlocked
version shall be removed.

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>
2017-01-30 09:22:20 +01:00
Viresh Kumar 37a73ec0c9 PM / OPP: Add per OPP table mutex
Add per OPP table lock to protect opp_table->opp_list.

Note that at few places opp_list is used under the rcu_read_lock() and
so a mutex can't be added there for now. This will be fixed by a later
patch.

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>
2017-01-30 09:22:20 +01:00
Viresh Kumar b6160e2693 PM / OPP: Split out part of _add_opp_table() and _remove_opp_table()
Split out parts of _add_opp_table() and _remove_opp_table() into
separate routines. This improves readability as well.

Should result in no functional changes.

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>
2017-01-27 11:49:10 +01:00
Viresh Kumar dc2c9ad52a PM / OPP: Don't expose srcu_head to register notifiers
Let the OPP core provide helpers to register notifiers for any device,
instead of exposing srcu_head outside of the core.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-27 11:49:09 +01:00
Viresh Kumar 3aa26a3b2e 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>
2017-01-27 11:49:09 +01:00
Viresh Kumar 8cd2f6e8f3 PM / OPP: Don't allocate OPP table from _opp_allocate()
There is no point in trying to find/allocate the table for every OPP
that is added for a device. It would be far more efficient to allocate
the table only once and pass its pointer to the routines that add the
OPP entry.

Locking is removed from _opp_add_static_v2() and _opp_add_v1() now as
the callers call them with that lock already held.

Call to _remove_opp_table() routine is also removed from _opp_free()
now, as opp_table isn't allocated from within _opp_allocate(). This is
handled by the routines which created the OPP table in the first place.

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>
2017-01-27 11:49:09 +01:00
Viresh Kumar 9274c89243 PM / OPP: Rename and split _dev_pm_opp_remove_table()
Later patches would want to remove OPP table (and its OPPs) using the
opp_table pointer instead of 'dev'.

In order to prepare for that, rename _dev_pm_opp_remove_table() as
_dev_pm_opp_find_and_remove_table() split out part 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>
2017-01-27 11:49:09 +01:00
Viresh Kumar 969fceb3c7 PM / OPP: Add light weight _opp_free() routine
The OPPs which are never successfully added using _opp_add() are not
required to be freed with the _opp_remove() routine, as a simple kfree()
is enough for them.

Introduce a new light weight routine _opp_free(), which will do that.

That also helps us removing the 'notify' parameter to _opp_remove(),
which isn't required anymore.

Note that _opp_free() contains a call to _remove_opp_table() as the OPP
table might have been added for this very OPP only. The
_remove_opp_table() routine returns quickly if there are more OPPs in
the table. This will be simplified in later patches though.

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>
2017-01-27 11:49:09 +01:00
Viresh Kumar 04a86a84c4 PM / OPP: Error out on failing to add static OPPs for v1 bindings
The code adding static OPPs for V2 bindings already does so. Make the V1
bindings specific code behave the same.

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>
2017-01-27 11:49:09 +01:00
Viresh Kumar 63a69ea4b8 PM / OPP: Rename _allocate_opp() to _opp_allocate()
Make the naming consistent with how other routines are named.

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>
2017-01-27 11:49:08 +01:00
Viresh Kumar 1715371ddd PM / OPP: Remove useless TODO
This TODO doesn't make sense anymore as we have all the information in a
single OPP table. Remove 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>
2017-01-27 11:49:08 +01:00
Viresh Kumar 7f8538ebae PM / OPP: Fix memory leak while adding duplicate OPPs
There are two types of duplicate OPPs that get different behavior from
the core:
A) An earlier OPP is marked 'available' and has same freq/voltages as
   the new one.
B) An earlier OPP with same frequency, but is marked 'unavailable' OR
   doesn't have same voltages as the new one.

The OPP core returns 0 for the first one, but -EEXIST for the second.

While the OPP core returns 0 for the first case, its callers don't free
the newly allocated OPP structure which isn't used anymore. Fix that by
returning -EBUSY instead of 0, but make the callers return 0 eventually.

As this isn't a critical fix, its not getting marked for stable kernel.

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>
2017-01-27 11:49:08 +01:00
Viresh Kumar e231f8d7ed PM / OPP: Don't WARN on multiple calls to dev_pm_opp_set_regulators()
If a platform specific OPP driver has called this routine first and set
the regulators, then the second call from cpufreq-dt driver will hit the
WARN_ON(). Remove the WARN_ON(), but continue to return error in such
cases.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-06 02:28:00 +01:00
Viresh Kumar 4dab160eb1 PM / OPP: Allow platform specific custom set_opp() callbacks
The generic set_opp() handler isn't sufficient for platforms with
complex DVFS.  For example, some TI platforms have multiple regulators
for a CPU device. The order in which various supplies need to be
programmed is only known to the platform code and its best to leave it
to it.

This patch implements APIs to register platform specific set_opp()
callback.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-06 02:27:59 +01:00
Viresh Kumar 947355850f PM / OPP: Separate out _generic_set_opp()
Later patches would add support for custom set_opp() callbacks. This
patch separates out the code for _generic_set_opp() handler in order to
prepare for that.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-06 02:27:59 +01:00
Viresh Kumar dfbe4678d7 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>
2016-12-06 02:27:59 +01:00
Viresh Kumar ce31781a75 PM / OPP: Pass struct dev_pm_opp_supply to _set_opp_voltage()
Pass the entire supply structure instead of all of its fields.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-06 02:27:59 +01:00
Viresh Kumar 0f0fe7e013 PM / OPP: Manage supply's voltage/current in a separate structure
This is a preparatory step for multiple regulator per device support.
Move the voltage/current variables to a new structure.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-06 02:27:59 +01:00
Viresh Kumar dc39d06fcd PM / OPP: Don't use OPP structure outside of rcu protected section
The OPP structure must not be used out of the rcu protected section.
Cache the values to be used in separate variables instead.

Cc: 4.6+ <stable@vger.kernel.org> # 4.6+
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-06 02:27:58 +01:00
Stephen Boyd 91291d9ad9 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>
2016-11-30 22:41:28 +01:00
Masahiro Yamada 349aa92e81 PM / OPP: fix debug/error messages in dev_pm_opp_of_get_sharing_cpus()
These log messages are wrong because _of_get_opp_desc_node() returns
an operating-points-v2 node.

Commit a6eed752f5 ("PM / OPP: passing NULL to PTR_ERR()") fixed
static checker warnings, and reworded the messages at the same time
(but the latter was not mentioned in the git-log).

Restore the correct messages.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-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>
2016-10-21 15:37:30 +02:00
Masahiro Yamada 4bee77dc73 PM / OPP: make _of_get_opp_desc_node() a static function
Since commit f47b72a15a ("PM / OPP: Move CONFIG_OF dependent code
in a separate file"), this function is defined and called only in
drivers/base/power/opp/of.c .

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21 15:36:07 +02:00
Dave Gerlach a4ee454593 PM / OPP: Don't support OPP if it provides supported-hw but platform does not
The OPP framework allows each OPP to set a opp-supported-hw property
which provides values that are matched against supported_hw values
provided by the platform to limit support for certain OPPs on specific
hardware. Currently, if the platform does not set supported_hw values,
all OPPs are interpreted as supported, even if they have provided their
own opp-supported-hw values.

If an OPP has provided opp-supported-hw, it is indicating that there is
some specific hardware configuration it is supported by. These constraints
should be honored, and if no supported_hw has been provided by the
platform, there is no way to determine if that OPP is actually supported,
so it should be marked as not supported.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-26 15:13:31 +02:00
Arnd Bergmann 4df27c9189 PM / OPP: avoid maybe-uninitialized warning
When CONFIG_OPTIMIZE_INLINING is set and we are building with -Wmaybe-uninitialized
enabled, we can get a warning for the opp core driver:

drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate':
drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used uninitialized in this function [-Wmaybe-uninitialized]

This has only now appeared as a result of commit 797da5598f ("PM / devfreq:
Add COMPILE_TEST for build coverage"), which makes the driver visible in
some configurations that didn't have it before.

The warning is a false positive that I got with gcc-6.1.1, but there is
a simple workaround in removing the local variables that we get warnings
for (all three are affected depending on the configuration). This also
makes the code easier to read.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-17 00:58:00 +02:00
Jisheng Zhang 067b7ce083 PM / OPP: optimize dev_pm_opp_set_rate() performance a bit
In dev_pm_opp_set_rate(), _find_opp_table() is called 4 times: once by
_get_opp_clk(), once by dev_pm_opp_set_rate() itself, and twice by
dev_pm_opp_find_freq_ceil(). If there are several opp_tables in the
system, three times of opp table finding is a big waste. This patch
reduced the call of _find_opp_table() to twice.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-28 23:54:16 +02:00
Viresh Kumar 79ee2e8f73 PM / OPP: Add 'UNKNOWN' status for shared_opp in struct opp_table
dev_pm_opp_get_sharing_cpus() returns 0 even in the case when the OPP
core doesn't know whether or not the table is shared. It works on the
majority of platforms, where the OPP table is never created before
invoking the function and then -ENODEV is returned by it.

But in the case of one platform (Jetson TK1) at least, the situation
is a bit different. The OPP table has been created (somehow) before
dev_pm_opp_get_sharing_cpus() is called and it returns 0. Its caller
treats that as 'the CPUs don't share OPPs' and that leads to degraded
performance.

Fix this by converting 'shared_opp' in struct opp_table to an enum
and making dev_pm_opp_get_sharing_cpus() return -EINVAL in case when
the value of that field is "access unknown", so that the caller can
handle it accordingly (cpufreq-dt considers that as 'all CPUs share
the table', for example).

Fixes: 6f707daa38 "PM / OPP: Add dev_pm_opp_get_sharing_cpus()"
Reported-and-tested-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw : Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16 15:50:36 +02:00
Rafael J. Wysocki c8541203a6 Merge back new material for v4.7. 2016-05-06 22:05:16 +02:00
Viresh Kumar f47b72a15a PM / OPP: Move CONFIG_OF dependent code in a separate file
Recently, a few issues were noticed in the code where CONFIG_OF wasn't
consistently used for many routines. The core file is big enough now and
ifdef hackery makes it less readable.

Move OF-specific code to another file and compile that only if CONFIG_OF
is enabled.

Compile-tested:
- For ARM (exynos) with CONFIG_OF enabled
- For X86 with CONFIG_OF disabled (have to enable CONFIG_PM_OPP separately)

No functional changes.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-06 13:22:49 +02:00
Viresh Kumar 21f8a99ce6 PM / OPP: Remove useless check
Regulators are optional for devices using OPPs and the OPP core
shouldn't be printing any errors for such missing regulators.

It was fine before the commit 0c717d0f9c, but that failed to update
this part of the code to remove an 'always true' check and an extra
unwanted print message.

Fix that now.

Fixes: 0c717d0f9c (PM / OPP: Initialize regulator pointer to an error value)
Reported-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.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>
2016-05-05 01:42:19 +02:00
Sudeep Holla 411466c508 PM / OPP: add non-OF versions of dev_pm_opp_{cpumask_, }remove_table
Functions dev_pm_opp_of_{cpumask_,}remove_table removes/frees all the
static OPP entries associated with the device and/or all cpus(in case
of cpumask) that are created from DT.

However the OPP entries are populated reading from the firmware or some
different method using dev_pm_opp_add are marked dynamic and can't be
removed using above functions.

This patch adds non DT/OF versions of dev_pm_opp_{cpumask_,}remove_table
to support the above mentioned usecase.

This is in preparation to make use of the same in scpi-cpufreq.c

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-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>
2016-05-05 01:38:44 +02:00
Arnd Bergmann ddbb74bc70 PM / OPP: pass cpumask by reference
The new use of dev_pm_opp_set_sharing_cpus resulted in a harmless compiler
warning with CONFIG_CPUMASK_OFFSTACK=y:

drivers/cpufreq/mvebu-cpufreq.c: In function 'armada_xp_pmsu_cpufreq_init':
include/linux/cpumask.h:550:25: error: passing argument 2 of 'dev_pm_opp_set_sharing_cpus' discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]

The problem here is that cpumask_var_t gets passed by reference, but
by declaring a 'const cpumask_var_t' argument, only the pointer is
constant, not the actual mask. This is harmless because the function
does not actually modify the mask.

This patch changes the function prototypes for all of the related functions
to pass a 'struct cpumask *' instead of 'cpumask_var_t', matching what
most other such functions do in the kernel. This lets us mark all the
other similar functions as taking a 'const' mask where possible,
and it avoids the warning without any change in object code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 947bd567f7 (mvebu: Use dev_pm_opp_set_sharing_cpus() to mark OPP tables as shared)
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-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>
2016-05-05 01:34:20 +02:00
Viresh Kumar 6f707daa38 PM / OPP: Add dev_pm_opp_get_sharing_cpus()
OPP core allows a platform to mark OPP table as shared, when the
platform isn't using operating-points-v2 bindings.

And, so there should be a non DT way of finding out if the OPP table is
shared or not.

This patch adds dev_pm_opp_get_sharing_cpus(), which first tries to get
OPP sharing information from the opp-table (in case it is already marked
as shared), otherwise it uses the existing DT way of finding sharing
information.

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>
2016-04-28 15:18:18 +02:00
Viresh Kumar dde370b23c PM / OPP: Mark cpumask as const in dev_pm_opp_set_sharing_cpus()
dev_pm_opp_set_sharing_cpus() isn't supposed to update the cpumask
passed as its parameter, and so it should always have been marked
'const'.

Do it now.

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>
2016-04-28 15:18:18 +02:00
Viresh Kumar 46e7a4e183 PM / OPP: Mark shared-opp for non-dt case
opp core allows OPPs to be explicitly marked as shared from platform
code, in case of operating-point v1 bindings.

Though we do everything fine in that case, we don't set the flag in the
opp-table to indicate that the OPPs are shared. It works fine today as
the flag isn't used anywhere else in the core, but we should be doing
the right thing by marking it set.

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>
2016-04-25 16:10:18 +02:00
Viresh Kumar 2c93104ff2 PM / OPP: Relocate dev_pm_opp_set_sharing_cpus()
Move dev_pm_opp_set_sharing_cpus() towards the end of the file. This
is required for better readability after the next patch is applied,
which adds dev_pm_opp_get_sharing_cpus().

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>
2016-04-25 16:10:16 +02:00
Viresh Kumar 45ca36ad7c PM / OPP: Add missing doc style comments
Few of the routines in cpu.c were missing these, add them.

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>
2016-04-25 16:10:14 +02:00
Viresh Kumar 2d74c6d565 PM / OPP: Propagate the error returned by _find_opp_table()
Don't send -EINVAL and propagate what's received from _find_opp_table().

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>
2016-04-25 16:10:11 +02:00
Viresh Kumar 2c2709dc69 PM / OPP: Rename structures for clarity
Stephen pointed out recently, that few structures always confuse him as
they aren't named properly. And this patch tries to address that:

Names are updated as:
- device_opp or dev_opp -> opp_table
- dev_opp_list -> opp_tables
- dev_opp_list_lock -> opp_table_lock
- device_list_opp -> opp_device (it was never a list, but a structure)
- list_dev -> opp_dev
- And similar changes in comments and function names as well.

This also fixes checkpatch warnings that were generated with this patch.

No functional changes.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
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>
2016-02-21 14:24:35 +01:00