Having no license specification in a module taints the kernel during load
with:
arm_big_little: module license 'unspecified' taints kernel.
and also the linker doesn't allow it to make use of GPL-exported symbols
which in this case also results in errors like:
arm_big_little: Unknown symbol cpufreq_register_driver (err 0)
. The header of the driver specifies a GPL v2 license, so note that
accordingly. While at it also add a description and an author and fix
the license in a companion file to explicit v2.
Reported-by: Andreas Schwab <schwab@suse.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpufreq core now supports the cpufreq_for_each_entry and
cpufreq_for_each_valid_entry macros helpers for iteration over the
cpufreq_frequency_table, so use them.
It should have no functional changes.
Signed-off-by: Stratos Karafotis <stratosk@semaphore.gr>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We have a per-CPU variable for managing which cluster a CPU belongs to.
Currently, physical_cluster is set for policy->cpu only which leads to
the following on some SoC's:
- There are two clusters:
- Cluster 0 has four ARM Cortex A7 CPUs (slower ones): 0,1,2,3
- Cluster 1 has four ARM Cortex A15 CPUs (faster ones): 4,5,6,7
- CPUs are booted in order 0,1..7 and so initially policy->cpu for A7 cluster
would be 0 and for A15 cluster would be 4.
- Now CPU4 (i.e. A15_0) is hotplugged out and so policy->cpu for A15 cluster
becomes 5 (i.e. A15_1).
- But physical cluster is only set for CPU0 and CPU4 in ARM big LITTLE driver
and isn't updated.
- Now freq change request comes for A15 cluster and we would try to update freq
of physical_cluster of CPU5, i.e. A15_1. And it is currently set to zero
(default value of uninitialized global variables).
- And so we actually try to change freq of A7 cluster instead of A15.
- This also results in kernel crash as sometimes we might request freq above
A7's limit and CPU may behave badly..
Fix this by initializing physical_cluster for all CPUs of a policy.
Based on previous work by Xin Wang.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
freq table is not per CPU but per policy, so it makes more sense to
keep it within struct cpufreq_policy instead of a per-cpu variable.
This patch does it. Over that, there is no need to set policy->freq_table
to NULL in ->exit(), as policy structure is going to be freed soon.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Sometimes boot loaders set CPU frequency to a value outside of frequency table
present with cpufreq core. In such cases CPU might be unstable if it has to run
on that frequency for long duration of time and so its better to set it to a
frequency which is specified in frequency table.
On some systems we can't really say what frequency we're running at the moment
and so for these we shouldn't check if we are running at a frequency present in
frequency table. And so we really can't force this for all the cpufreq drivers.
Hence we are created another flag here: CPUFREQ_NEED_INITIAL_FREQ_CHECK that
will be marked by platforms which want to go for this check at boot time.
Initially this is done for all ARM platforms but others may follow if required.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Most of the drivers do following in their ->target_index() routines:
struct cpufreq_freqs freqs;
freqs.old = old freq...
freqs.new = new freq...
cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
/* Change rate here */
cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
This is replicated over all cpufreq drivers today and there doesn't exists a
good enough reason why this shouldn't be moved to cpufreq core instead.
There are few special cases though, like exynos5440, which doesn't do everything
on the call to ->target_index() routine and call some kind of bottom halves for
doing this work, work/tasklet/etc..
They may continue doing notification from their own code as flag:
CPUFREQ_ASYNC_NOTIFICATION is already set for them.
All drivers are also modified in this patch to avoid breaking 'git bisect', as
double notification would happen otherwise.
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The b.L switcher can be turned on/off at run time. It is therefore
necessary to change the cpufreq driver behavior accordingly.
The driver must be unregistered/registered with the cpufreq core
to reconfigure freq tables for the virtual or actual CPUs. This is
accomplished via the b.L switcher notifier callback.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds IKS (In Kernel Switcher) support to cpufreq driver.
This creates a combined freq table for A7-A15 CPU pairs. A7 frequencies
are virtualized and scaled down to half the actual frequencies to
approximate a linear scale across the combined A7+A15 range. When the
requested frequency change crosses the A7-A15 boundary a cluster switch
is invoked.
Based on earlier work from Sudeep KarkadaNagesha.
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently, the prototype of cpufreq_drivers target routines is:
int target(struct cpufreq_policy *policy, unsigned int target_freq,
unsigned int relation);
And most of the drivers call cpufreq_frequency_table_target() to get a valid
index of their frequency table which is closest to the target_freq. And they
don't use target_freq and relation after that.
So, it makes sense to just do this work in cpufreq core before calling
cpufreq_frequency_table_target() and simply pass index instead. But this can be
done only with drivers which expose their frequency table with cpufreq core. For
others we need to stick with the old prototype of target() until those drivers
are converted to expose frequency tables.
This patch implements the new light weight prototype for target_index() routine.
It looks like this:
int target_index(struct cpufreq_policy *policy, unsigned int index);
CPUFreq core will call cpufreq_frequency_table_target() before calling this
routine and pass index to it. Because CPUFreq core now requires to call routines
present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time.
This also marks target() interface as deprecated. So, that new drivers avoid
using it. And Documentation is updated accordingly.
It also converts existing .target() to newly defined light weight
.target_index() routine for many driver.
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Since Operating Performance Points (OPP) functions are specific
to device specific power management, be specific and rename opp.h
to pm_opp.h
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since Operating Performance Points (OPP) functions are specific to
device specific power management, be specific and rename opp_*
accessors in OPP library with dev_pm_opp_* equivalent.
Affected functions are:
opp_get_voltage
opp_get_freq
opp_get_opp_count
opp_find_freq_exact
opp_find_freq_floor
opp_find_freq_ceil
opp_add
opp_enable
opp_disable
opp_get_notifier
opp_init_cpufreq_table
opp_free_cpufreq_table
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-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>
Currently clk_get_sys is used with cpu-cluster.<n> as the device id
which is incorrect. It should be connection/consumer ID instead.
It is possible to specify input clock in the cpu device node along
with the optional clock-name. clk_get_sys can't handle that.
This patch replaces clk_get_sys with clk_get to extend support for
clocks specified in the device tree cpu node.
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Many common initializations of struct policy are moved to core now and hence
this driver doesn't need to do it. This patch removes such code.
Most recent of those changes is to call ->get() in the core after calling
->init().
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Most of the CPUFreq drivers do similar things in .exit() and .verify() routines
and .attr. So its better if we have generic routines for them which can be used
by cpufreq drivers then.
This patch uses these generic routines in the arm_big_little driver.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use cpufreq_driver->flags to mark CPUFREQ_HAVE_GOVERNOR_PER_POLICY instead
of a separate field within cpufreq_driver. This will save some bytes of
memory.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Drivers which have an exit path must call cpufreq_frequency_table_put_attr() if
they have called cpufreq_frequency_table_get_attr() in their init path.
This driver was missing this part and is fixed with this patch.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Lets use cpufreq_table_validate_and_show() instead of calling
cpufreq_frequency_table_cpuinfo() and cpufreq_frequency_table_get_attr().
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both
should be called or both shouldn't be.
In case we have started PRECHANGE notifier and found an error, we must call
POSTCHANGE notifier with freqs.new = freqs.old to guarantee that sequence of
calling notifiers is complete.
This patch fixes it.
This also removes code setting policy->cur as this is also done by POSTCHANGE
notifier.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The message printed at the end of driver->init() doesn't include the
"cpufreq" string at all and so is difficult to find in dmesg. Add
function name to that message to clearly state where the message is
coming from.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The cpu_to_cluster() function may be used by glue drivers, so it's
better to keep it in arm_big_little.h.
[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This driver isn't updated to work with latest cpufreq core updates that happened
recently. Fix them.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
big LITTLE is ARM's new Architecture focussing power/performance needs of modern
world. More information about big LITTLE can be found here:
http://www.arm.com/products/processors/technologies/biglittleprocessing.phphttp://lwn.net/Articles/481055/
In order to keep cpufreq support for all big LITTLE platforms simple/generic,
this patch tries to add a generic cpufreq driver layer for all big LITTLE
platforms.
The driver is divided into two parts:
- Core driver: Generic and shared across all big LITTLE SoC's
- Glue drivers: Per platform drivers providing ops to the core driver
This patch adds in a generic glue driver which would extract information from
Device Tree.
Future SoC's can either reuse the DT glue or write their own depending on the
need.
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Uwe Kleine-König
Stratos Karafotis
viresh kumar
Nicolas Pitre
Rafael J. Wysocki
Nishanth Menon
Sudeep KarkadaNagesha