We are freeing parent node in success cases but not in failure cases.
Let's do it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
With commit 1e4b545, regulator_get will now return -EPROBE_DEFER
when the cpu0-supply node is present, but the regulator is not yet
registered.
It is possible for this to occur when the regulator registration
by itself might be defered due to some dependent interface not yet
instantiated. For example: an regulator which uses I2C and GPIO might
need both systems available before proceeding, in this case, the
regulator might defer it's registration.
However, the cpufreq-cpu0 driver assumes that any un-successful
return result is equivalent of failure.
When the regulator_get returns failure other than -EPROBE_DEFER, it
makes sense to assume that supply node is not present and proceed
with the assumption that only clock control is necessary in the
platform.
With this change, we can now handle the following conditions:
a) cpu0-supply binding is not present, regulator_get will return
appropriate error result, resulting in cpufreq-cpu0 driver
controlling just the clock.
b) cpu0-supply binding is present, regulator_get returns
-EPROBE_DEFER, we retry resulting in cpufreq-cpu0 driver
registering later once the regulator is available.
c) cpu0-supply binding is present, regulator_get returns
-EPROBE_DEFER, however, regulator never registers, we retry until
cpufreq-cpu0 driver fails to register pointing at device tree
information bug. However, in this case, the fact that
cpufreq-cpu0 operates with clock only when the DT binding clearly
indicates need of a supply is a bug of it's own.
d) cpu0-supply gets an regulator at probe - cpufreq-cpu0 driver
controls both the clock and regulator
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pm-cpufreq: (57 commits)
cpufreq: MAINTAINERS: Add co-maintainer
cpufreq: pxa2xx: initialize variables
ARM: S5pv210: compiling issue, ARM_S5PV210_CPUFREQ needs CONFIG_CPU_FREQ_TABLE=y
cpufreq: cpu0: Put cpu parent node after using it
cpufreq: ARM big LITTLE: Adapt to latest cpufreq updates
cpufreq: ARM big LITTLE: put DT nodes after using them
cpufreq: Don't call __cpufreq_governor() for drivers without target()
cpufreq: exynos5440: Protect OPP search calls with RCU lock
cpufreq: dbx500: Round to closest available freq
cpufreq: Call __cpufreq_governor() with correct policy->cpus mask
cpufreq / intel_pstate: Optimize intel_pstate_set_policy
cpufreq: OMAP: instantiate omap-cpufreq as a platform_driver
arm: exynos: Enable OPP library support for exynos5440
cpufreq: exynos: Remove error return even if no soc is found
cpufreq: exynos: Add cpufreq driver for exynos5440
cpufreq: AMD "frequency sensitivity feedback" powersave bias for ondemand governor
cpufreq: ondemand: allow custom powersave_bias_target handler to be registered
cpufreq: convert cpufreq_driver to using RCU
cpufreq: powerpc/platforms/cell: move cpufreq driver to drivers/cpufreq
cpufreq: sparc: move cpufreq driver to drivers/cpufreq
...
Conflicts:
MAINTAINERS (with commit a8e39c3 from pm-cpuidle)
drivers/cpufreq/cpufreq_governor.h (with commit beb0ff3)
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: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael 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: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rafael 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: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael 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: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael 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: Jonghwan Choi <jhbird.choi@samsung.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
policy->shared_type field was added only for SoCs with ACPI support:
commit 3b2d99429e
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: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Rafael 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: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
Signed-off-by: Rafael 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: Mark Langsdorf <mark.langsdorf@calxeda.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Rafael 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: Jack Mitchell <jack@embed.me.uk>
Tested-by: Alexander Holler <holler@ahsoftware.de>
Tested-by: Jack Mitchell <jack@embed.me.uk>
Acked-by: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Rafael 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: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: AnilKumar Ch <anilkumar@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
