Parent node must be put after using it to balance its usage count. This was
missing in cpufreq-cpu0 driver. Fix it.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

policy->cpus contains all online cpus that have single shared clock line. And
their frequencies are always updated together.

Many SMP system's cpufreq drivers take care of this in individual drivers but
the best place for this code is in cpufreq core.

This patch modifies cpufreq_notify_transition() to notify frequency change for
all cpus in policy->cpus and hence updates all users of this API.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NStephen Warren <swarren@nvidia.com>
Tested-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently we are simply returning from target() if we encounter some error after
broadcasting CPUFREQ_PRECHANGE notifier. Which looks to be wrong as others might
depend on POSTCHANGE notifier for their functioning.

So, better broadcast CPUFREQ_POSTCHANGE notifier for these failure cases too,
but with old frequency.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

It is not possible for init() to be called for any cpu other than cpu0. During
bootup whatever cpu is used to boot system will be assigned as cpu0. And later
on policy->cpu can only change if we hotunplug all cpus first and then hotplug
them back in different order, which isn't possible (system requires atleast one
cpu to be up always :)).

Though I can see one situation where policy->cpu can be different then zero.
- Hot-unplug cpu 0.
- rmmod cpufreq-cpu0 module
- insmod it back
- hotplug cpu 0 again.

Here, policy->cpu would be different. But the driver doesn't have any dependency
on cpu0 as such. We don't mind which cpu of a system is policy->cpu and so this
check is just not required.

Remove it.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

clk_round_rate() returns singed value which was assigned to an unsigned
variable.
So it can't be checked for negative.
Signed-off-by: NJonghwan Choi <jhbird.choi@samsung.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

policy->shared_type field was added only for SoCs with ACPI support:

commit 3b2d9942
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Wed Dec 14 15:05:00 2005 -0500

    P-state software coordination for ACPI core

    http://bugzilla.kernel.org/show_bug.cgi?id=5737

Many non-ACPI systems are filling this field by mistake, which makes its usage
confusing. Lets clean it.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

As multiplatform build is being adopted by more and more ARM platforms,
initcall function should be used very carefully.  For example, when
GENERIC_CPUFREQ_CPU0 is built in the kernel, cpu0_cpufreq_driver_init()
will be called on all the platforms to initialize cpufreq-cpu0 driver.

To eliminate this undesired the effect, the patch changes cpufreq-cpu0
driver to have it instantiated as a platform_driver.  Then it will only
run on platforms that create the platform_device "cpufreq-cpu0".

Along with the change, it also changes cpu_dev to be &pdev->dev,
so that managed functions can start working, and module build gets
supported too.

The highbank-cpufreq driver is also updated accordingly to adapt the
changes on cpufreq-cpu0.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NMark Langsdorf <mark.langsdorf@calxeda.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Highbank processors depend on the external ECME to perform voltage
management based on a requested frequency. Communication between the
A9 cores and the ECME happens over the pl320 IPC channel.
Signed-off-by: NMark Langsdorf <mark.langsdorf@calxeda.com>
Reviewed-by: NShawn Guo <shawn.guo@linaro.org>
Reviewed-by: NMike Turquette <mturquette@linaro.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>

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>

It adds a generic cpufreq driver for CPU0 frequency management based on
clk, regulator, OPP and device tree support.  It can support both
uniprocessor (UP) and those symmetric multiprocessor (SMP) systems which
share clock and voltage across all CPUs.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NAnilKumar Ch <anilkumar@ti.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>