This patch fixes following sparse warning:

drivers/cpufreq/spear-cpufreq.c:33:5: warning: symbol 'spear_cpufreq_verify' was
not declared. Should it be static?
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This is how the core works:
cpufreq_driver_unregister()
 - subsys_interface_unregister()
   - for_each_cpu() call cpufreq_remove_dev(), i.e. 0,1,2,3,4 when we
     unregister.

cpufreq_remove_dev():
 - Remove policy node
 - Call cpufreq_add_dev() for next cpu, sharing mask with removed cpu.
   i.e. When cpu 0 is removed, we call it for cpu 1. And when called for cpu 2,
   we call it for cpu 3.
   - cpufreq_add_dev() would call cpufreq_driver->init()
   - init would return mask as AND of 2, 3 and 4 for cluster A7.
   - cpufreq core would do online_cpu && policy->cpus
     Here is the BUG(). Because cpu hasn't died but we have just unregistered
     the cpufreq driver, online cpu would still have cpu 2 in it. And so thing
     go bad again.

Solution: Keep cpumask of cpus that are registered with cpufreq core and clear
	  cpus when we get a call from subsys_interface_unregister() via
	  cpufreq_remove_dev().
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Because cpufreq core and governors worry only about the online cpus, if a cpu is
hot [un]plugged, we must notify governors about it, otherwise be ready to expect
something unexpected.

We already have notifiers in the form of CPUFREQ_GOV_START/CPUFREQ_GOV_STOP, we
just need to call them now.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq core doesn't manage offline cpus and if driver->init() has returned
mask including offline cpus, it may result in unwanted behavior by cpufreq core
or governors.

We need to get only online cpus in this mask. There are two places to fix this
mask, cpufreq core and cpufreq driver. It makes sense to do this at common place
and hence is done in core.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Modify update_sampling_rate() to check, and eventually immediately
schedule, all CPU's do_dbs_timer delayed work.

This is required in case of software coordinated CPUs, as we now have a
separate delayed work for each CPU.
Signed-off-by: NFabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Modify conservative timer to not resample CPU utilization if recently
sampled from another SW coordinated core.
Signed-off-by: NFabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Modify ondemand timer to not resample CPU utilization if recently
sampled from another SW coordinated core.
Signed-off-by: NFabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch fixes a bug that occurred when we had load on a secondary CPU
and the primary CPU was sleeping. Only one sampling timer was spawned
and it was spawned as a deferred timer on the primary CPU, so when a
secondary CPU had a change in load this was not detected by the cpufreq
governor (both ondemand and conservative).

This patch make sure that deferred timers are run on all CPUs in the
case of software controlled CPUs that run on the same frequency.
Signed-off-by: NRickard Andersson <rickard.andersson@stericsson.com>
Signed-off-by: NFabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The acpi core will call request_module("acpi-cpufreq") on subsystem init,
but this will fail if the module isn't available at that stage of boot.
Add some module aliases to ensure that udev can load the module on Intel
and AMD systems with the appropriate feature bits - I /think/ that this
will also work on VIA systems, but haven't verified that.

References: http://lkml.kernel.org/r/1448223.sdUJnNSRz4@vostro.rjw.lanSigned-off-by: NMatthew Garrett <matthew.garrett@nebula.com>
Tested-by: NLeonid Isaev <lisaev@umail.iu.edu>
Acked-by: NBorislav Petkov <bp@suse.de>
Cc: 3.7+ <stable@vger.kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

OPP pointer is RCU protected, hence after finding it, de-reference
also should be protected with the same RCU context else the OPP
pointer may become invalid.
Reported-by: NJack Mitchell <jack@embed.me.uk>
Tested-by: NAlexander Holler <holler@ahsoftware.de>
Tested-by: NJack Mitchell <jack@embed.me.uk>
Acked-by: NAlexander Holler <holler@ahsoftware.de>
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

OPP pointer is RCU protected, hence after finding it, de-reference
also should be protected with the same RCU context else the OPP
pointer may become invalid.
Reported-by: NAlexander Holler <holler@ahsoftware.de>
Tested-by: NAlexander Holler <holler@ahsoftware.de>
Acked-by: NAlexander Holler <holler@ahsoftware.de>
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Andreas reports in https://bugzilla.kernel.org/show_bug.cgi?id=51741
that with his Gentoo config, acpi-cpufreq wasn't enabled and
powernow-k8 couldn't handoff properly to acpi-cpufreq leading to
running without P-state support (i.e., cores are constantly in P0).

To alleaviate that, we need to make powernow-k8 depend on acpi-cpufreq
so that acpi-cpufreq is always present.

References: https://bugzilla.kernel.org/show_bug.cgi?id=51741Reported-by: NAndreas <linuxuser330250@gmx.net>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: 3.7+ <stable@vger.kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Since commit 2aacdfff entitled "cpufreq: Move common part from governors
to separate file", whenever the drivers that depend on this new file
(cpufreq_ondemand or cpufreq_conservative) are built as modules, a new
module named cpufreq_governor is created because the Makefile includes
cpufreq_governor.o twice. As drivers/cpufreq/cpufreq_governor.c contains no
MODULE directives, the resulting module has no license specified, which
results in logging of a "module license 'unspecified' taints kernel". In
addition, a number of globals are exported GPL only, and are therefore
not available. This fix establishes a new boolean configuration variable
that forces cpufreq_governor.o to be linked into the kernel whenever
either cpufreq_ondemand or cpufreq_conservative is selected.
Signed-off-by: NLarry Finger <Larry.Finger@lwfinger.net>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This is only solution I can think of. User decides if he wants this
driver on his machine. I don't have enough knowledge and time to find
the reason why same code works on some machines and doesn't on others
which use the same, or very similar, chipset and processor.
Signed-off-by: NRafał Bilski <rafalbilski@interia.pl>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch forces complete struct cpufreq_stats allocation for all cpus before
registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions
cpufreq_stat_notifier_trans() can be called in the middle of stats allocation,
in this case cpufreq_stats_table already exists, but stat->freq_table is NULL.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix cpufreq_gov_ondemand to skip CPU where another governor is used.

The bug present itself as NULL pointer access on the mutex_lock() call,
an can be reproduced on an SMP machine by setting the default governor
to anything other than ondemand, setting a single CPU's governor to
ondemand, then changing the sample rate by writing on:

> /sys/devices/system/cpu/cpufreq/ondemand/sampling_rate

Backtrace:

Nov 26 17:36:54 balto kernel: [  839.585241] BUG: unable to handle kernel NULL pointer dereference at           (null)
Nov 26 17:36:54 balto kernel: [  839.585311] IP: [<ffffffff8174e082>] __mutex_lock_slowpath+0xb2/0x170
[snip]
Nov 26 17:36:54 balto kernel: [  839.587005] Call Trace:
Nov 26 17:36:54 balto kernel: [  839.587030]  [<ffffffff8174da82>] mutex_lock+0x22/0x40
Nov 26 17:36:54 balto kernel: [  839.587067]  [<ffffffff81610b8f>] store_sampling_rate+0xbf/0x150
Nov 26 17:36:54 balto kernel: [  839.587110]  [<ffffffff81031e9c>] ?  __do_page_fault+0x1cc/0x4c0
Nov 26 17:36:54 balto kernel: [  839.587153]  [<ffffffff813309bf>] kobj_attr_store+0xf/0x20
Nov 26 17:36:54 balto kernel: [  839.587192]  [<ffffffff811bb62d>] sysfs_write_file+0xcd/0x140
Nov 26 17:36:54 balto kernel: [  839.587234]  [<ffffffff8114c12c>] vfs_write+0xac/0x180
Nov 26 17:36:54 balto kernel: [  839.587271]  [<ffffffff8114c472>] sys_write+0x52/0xa0
Nov 26 17:36:54 balto kernel: [  839.587306]  [<ffffffff810321ce>] ?  do_page_fault+0xe/0x10
Nov 26 17:36:54 balto kernel: [  839.587345]  [<ffffffff81751202>] system_call_fastpath+0x16/0x1b
Signed-off-by: NFabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

SPEAr is an ARM based family of SoCs. This patch adds in support of cpufreq
driver for SPEAr SoCs. It is supported via DT only and so bindings are present
in binding document.
Signed-off-by: NDeepak Sikri <deepak.sikri@st.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This change was made by commit 8636fd28 (cpufreq: fix jiffies/cputime
mixup in conservative/ondemand governors) before, but then it has
been reverted inadvertently by commit 4471a34f (cpufreq: governors:
remove redundant code).

The changelog of commit 8636fd28's says:

  The function get_cpu_idle_time_jiffy in both the conservative and
  ondemand governors use jiffies_to_usecs to convert a cputime value
  to usecs which gives the wrong value on architectures where cputime
  and jiffies use different units.  Only matters if NO_HZ is
  disabled, since otherwise get_cpu_idle_time_us should already
  return a valid value, and get_cpu_idle_time_jiffy isn't actually
  called.

Since now we have only one common get_cpu_idle_time_jiffy() used by
both governors in question, modify it along the lines of commit
8636fd28 to restore the correct behavior.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>

Restore the correct delay value for ondemand's od_dbs_timer, as it was
changed erroneously in commit 83f0e55 (cpufreq: governors: remove
redundant code).
Signed-off-by: NFabio Baltieri <fabio.baltieri@linaro.org>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Fixes following sparse error.
drivers/cpufreq/exynos-cpufreq.c:34:5: warning: symbol
'exynos_verify_speed' was not declared. Should it be static?
drivers/cpufreq/exynos-cpufreq.c:40:14: warning: symbol
'exynos_getspeed' was not declared. Should it be static?
Signed-off-by: NTushar Behera <tushar.behera@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

On Exynos SoCs all cores share the same frequency setting, so changing
frequency of one core will affect rest of cores.

This patch modifies the exynos-cpufreq driver to inform cpufreq core
about this behavior and broadcast frequency change notifications for all
cores.
Signed-off-by: NTomasz Figa <t.figa@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer
needed.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove an unnecessary initializer for the 'ret' variable in
__cpufreq_set_policy().

[rjw: Modified the subject and changelog slightly.]
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

__cpufreq_driver_target() must not pass target frequency beyond the
limits of current policy.

Today most of cpufreq platform drivers are doing this check in their
target routines. Why not move it to __cpufreq_driver_target()?
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Avoid calling cpufreq driver's target() routine if new frequency is same as
policies current frequency.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

cpufreq_disabled() is a local function, so should be marked static.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There were few sparse warnings due to mismatch of type on function arguments.
Two types were used u64 and cputime64_t. Both are actually u64, so use u64 only.
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Initially ondemand governor was written and then using its code conservative
governor is written. It used a lot of code from ondemand governor, but copy of
code was created instead of using the same routines from both governors. Which
increased code redundancy, which is difficult to manage.

This patch is an attempt to move common part of both the governors to
cpufreq_governor.c file to come over above mentioned issues.

This shouldn't change anything from functionality point of view.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

There is no need to do cpufreq_get_cpu() and cpufreq_put_cpu() for drivers that
don't support getavg() routine.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The function get_cpu_idle_time_jiffy in both the conservative and
ondemand governors use jiffies_to_usecs to convert a cputime value to
usecs which gives the wrong value on architectures where cputime and
jiffies use different units.  Only matters if NO_HZ is disabled, since
otherwise get_cpu_idle_time_us should already return a valid value, and
get_cpu_idle_time_jiffy isn't actually called.
Signed-off-by: NAndreas Schwab <schwab@linux-m68k.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

With debug options on, it is difficult to locate cpufreq core's debug prints.
Fix this by prefixing debug prints with KBUILD_MODNAME.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Multiple cpufreq governers have defined similar get_cpu_idle_time_***()
routines. These routines must be moved to some common place, so that all
governors can use them.

So moving them to cpufreq_governor.c, which seems to be a better place for
keeping these routines.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Arrays for governer and driver name are of size CPUFREQ_NAME_LEN or 16.
i.e. 15 bytes for name and 1 for trailing '\0'.

When cpufreq driver print these names (for sysfs), it includes '\n' or ' ' in
the fmt string and still passes length as CPUFREQ_NAME_LEN. If the driver or
governor names are using all 15 fields allocated to them, then the trailing '\n'
or ' ' will never be printed. And so commands like:

root@linaro-developer# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver

will print something like:

cpufreq_foodrvroot@linaro-developer#

Fix this by increasing print length by one character.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

show_bios_limit is mistakenly written as show_scaling_driver in a comment
describing purpose of show_bios_limit() routine.

Fix it.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Using the armss clk to update the frequency makes the driver no more
directly dependant on the prmcu API.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

By fetching the table as platform data we do not need the internally
hardcoded cpufreq table anymore.

Moreover the corresponding arm_opp idx2opp table, used for mapping
frequency to correct opp bits is also removed. This due to that the
opp bits is put directly in the index field of the cpufreq table.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NJonas Aaberg <jonas.aberg@stericsson.com>
Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

To fetch the mfd child device we register the cpufreq driver
as a platform driver.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NJonas Aaberg <jonas.aberg@stericsson.com>
Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

Change the Andreas' email address in drivers/cpufreq/powernow-k8.c.
Signed-off-by: NAndreas Herrmann <herrmann.der.user@googlemail.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>