Commit Graph

1432 Commits

Author SHA1 Message Date
Viresh Kumar 3782902983 cpufreq: Remove cpufreq_update_policy()
cpufreq_update_policy() was kept as a separate routine earlier as it was
handling migration of sysfs directories, which isn't the case anymore.
It is only updating policy->cpu now and is called by a single caller.

The WARN_ON() isn't really required anymore, as we are just updating the
cpu now, not moving the sysfs directories.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:03:04 +02:00
Viresh Kumar 9591becbf2 cpufreq: Restart governor as soon as possible
__cpufreq_remove_dev_finish() is doing two things today:
- Restarts the governor if some CPUs from concerned policy are still
  online.
- Frees the policy if all CPUs are offline.

The first task of restarting the governor can be moved to
__cpufreq_remove_dev_prepare() to restart the governor early. There is
no race between _prepare() and _finish() as they would be handling
completely different cases. _finish() will only be required if we are
going to free the policy and that has nothing to do with restarting the
governor.

Original-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:02:45 +02:00
Viresh Kumar 3654c5cc81 cpufreq: Call cpufreq_policy_put_kobj() from cpufreq_policy_free()
cpufreq_policy_put_kobj() is actually part of freeing the policy and can
be called from cpufreq_policy_free() directly instead of a separate
call.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:02:40 +02:00
Viresh Kumar 2fc3384dc7 cpufreq: Initialize policy->kobj while allocating policy
policy->kobj is required to be initialized once in the lifetime of a
policy.  Currently we are initializing it from __cpufreq_add_dev() and
that doesn't look to be the best place for doing so as we have to do
this on special cases (like: !recover_policy).

We can initialize it from a more obvious place cpufreq_policy_alloc()
and that will make code look cleaner, specially the error handling part.

The error handling part of __cpufreq_add_dev() was doing almost the same
thing while recover_policy is true or false. Fix that as well by always
calling cpufreq_policy_put_kobj() with an additional parameter to skip
notification part of it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:01:54 +02:00
Viresh Kumar 87549141d5 cpufreq: Stop migrating sysfs files on hotplug
When we hot-unplug a cpu, we remove its sysfs cpufreq directory and if
the outgoing cpu was the owner of policy->kobj earlier then we migrate
the sysfs directory to under another online cpu.

There are few disadvantages this brings:
- Code Complexity
- Slower hotplug/suspend/resume
- sysfs file permissions are reset after all policy->cpus are offlined
- CPUFreq stats history lost after all policy->cpus are offlined
- Special management of sysfs stuff during suspend/resume

To overcome these, this patch modifies the way sysfs directories are
managed:
- Select sysfs kobjects owner while initializing policy and don't change
  it during hotplugs. Track it with kobj_cpu created earlier.

- Create symlinks for all related CPUs (can be offline) instead of
  affected CPUs on policy initialization and remove them only when the
  policy is freed.

- Free policy structure only on the removal of cpufreq-driver and not
  during hotplug/suspend/resume, detected by checking 'struct
  subsys_interface *' (Valid only when called from
  subsys_interface_unregister() while unregistering driver).

Apart from this, special care is taken to handle physical hoplug of CPUs
as we wouldn't remove sysfs links or remove policies on logical
hotplugs. Physical hotplug happens in the following sequence.

Hot removal:
- CPU is offlined first, ~ 'echo 0 >
  /sys/devices/system/cpu/cpuX/online'
- Then its device is removed along with all sysfs files, cpufreq core
  notified with cpufreq_remove_dev() callback from subsys-interface..

Hot addition:
- First the device along with its sysfs files is added, cpufreq core
  notified with cpufreq_add_dev() callback from subsys-interface..
- CPU is onlined, ~ 'echo 1 > /sys/devices/system/cpu/cpuX/online'

We call the same routines with both hotplug and subsys callbacks, and we
sense physical hotplug with cpu_offline() check in subsys callback. We
can handle most of the stuff with regular hotplug callback paths and
add/remove cpufreq sysfs links or free policy from subsys callbacks.

Original-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-11 01:00:42 +02:00
Viresh Kumar 11e584cfb8 cpufreq: Don't allow updating inactive policies from sysfs
Later commits would change the way policies are managed today. Policies
wouldn't be freed on cpu hotplug (currently they aren't freed only for
suspend), and while the CPU is offline, the sysfs cpufreq files would
still be present.

User may accidentally try to update the sysfs files in following
directory: '/sys/devices/system/cpu/cpuX/cpufreq/'. And that would
result in undefined behavior as policy wouldn't be active then.

Apart from updating the store() routine, we also update __cpufreq_get()
which can call cpufreq_out_of_sync(). The later routine tries to update
policy->cur and starts notifying kernel about it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-10 02:11:45 +02:00
Doug Smythies 6c1e45917d intel_pstate: Force setting target pstate when required
During initialization and exit it is possible that the target pstate
might not actually be set. Furthermore, the result can be that the
driver and the processor are out of synch and, under some conditions,
the driver might never send the processor the proper target pstate.

This patch adds a bypass or do_checks flag to the call to
intel_pstate_set_pstate. If bypass, then specifically bypass clamp
checks and the do not send if it is the same as last time check. If
do_checks, then, and as before, do the current policy clamp checks,
and do not do actual send if the new target is the same as the old.

Signed-off-by: Doug Smythies <dsmythies@telus.net>
Reported-by: Marien Zwart <marien.zwart@gmail.com>
Reported-by: Alex Lochmann <alexander.lochmann@tu-dortmund.de>
Reported-by: Piotr Ko?aczkowski <pkolaczk@gmail.com>
Reported-by: Clemens Eisserer <linuxhippy@gmail.com>
Tested-by: Marien Zwart <marien.zwart@gmail.com>
Tested-by: Doug Smythies <dsmythies@telus.net>
[ rjw: Dropped pointless symbol definitions, rebased ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-10 02:08:27 +02:00
Doug Smythies f16255eb93 intel_pstate: change some inconsistent debug information
Commit ce717613f3 (intel_pstate: Turn per cpu printk into pr_debug)
turned per cpu printk into pr_debug.  However, only half of the change
was done, introducing an inconsistency between entry and exit from
driver pstate control.  This patch changes the exit message to pr_debug
also.

The various messages are inconsistent with respect to any identifier
text that can be used to help isolate the desired information from a
huge log.  This patch makes a consistent identifier portion of the
string.

Amends: ce717613f3 (intel_pstate: Turn per cpu printk into pr_debug)
Signed-off-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-06-10 01:57:14 +02:00
Saravana Kannan 9d16f20711 cpufreq: Track cpu managing sysfs kobjects separately
In order to prepare for the next few commits, that will stop migrating
sysfs files on cpu hotplug, this patch starts managing sysfs-cpu
separately.

The behavior is still the same as we are still migrating sysfs files on
hotplug, later commits would change that.

Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-23 00:49:04 +02:00
Shailendra Verma 58405af632 cpufreq: Fix for typos in two comments
Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-22 23:59:44 +02:00
Viresh Kumar 18bf3a124e cpufreq: Mark policy->governor = NULL for inactive policies
Later commits would change the way policies are managed today. Policies
wouldn't be freed on cpu hotplug (currently they aren't freed on
suspend), and while the CPU is offline, the sysfs cpufreq files would
still be present.

Because we don't mark policy->governor as NULL, it still contains
pointer of the last used governor. And if the governor is removed, while
all the CPUs of a policy are hotplugged out, this pointer wouldn't be
valid anymore. And if we try to read the 'scaling_governor', etc.  from
sysfs, it will result in kernel OOPs.

To prevent this, mark policy->governor as NULL for all inactive policies
while the governor is removed from kernel.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-15 02:46:45 +02:00
Viresh Kumar 4573237b01 cpufreq: Manage governor usage history with 'policy->last_governor'
History of which governor was used last is common to all CPUs within a
policy and maintaining it per-cpu isn't the best approach for sure.

Apart from wasting memory, this also increases the complexity of
managing this data structure as it has to be updated for all CPUs.

To make that somewhat simpler, lets store this information in a new
field 'last_governor' in struct cpufreq_policy and update it on removal
of last cpu of a policy.

As a side-effect it also solves an old problem, consider a system with
two clusters 0 & 1. And there is one policy per cluster.

Cluster 0: CPU0 and 1.
Cluster 1: CPU2 and 3.

 - CPU2 is first brought online, and governor is set to performance
   (default as cpufreq_cpu_governor wasn't set).
 - Governor is changed to ondemand.
 - CPU2 is taken offline and cpufreq_cpu_governor is updated for CPU2.
 - CPU3 is brought online.
 - Because cpufreq_cpu_governor wasn't set for CPU3, the default governor
   performance is picked for CPU3.

This patch fixes the bug as we now have a single variable to update for
policy.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-15 02:44:17 +02:00
Viresh Kumar 9104bb26c7 cpufreq: Don't traverse all active policies to find policy for a cpu
We reach here while adding policy for a CPU and enter into the 'if'
block only if a policy already exists for the CPU.

As cpufreq_cpu_data is set for all policy->related_cpus now, when the
policy is first added, we can use that to find the CPU's policy instead
of traversing the list of all active policies.

Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-15 02:38:18 +02:00
Viresh Kumar 3914d37910 cpufreq: Get rid of cpufreq_cpu_data_fallback
We can extract the same information from cpufreq_cpu_data as it is also
available for inactive policies now. And so don't need
cpufreq_cpu_data_fallback anymore.

Also add a WARN_ON() for the case where we try to restore from an active
policy.

Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-15 02:35:57 +02:00
Viresh Kumar 988bed09d3 cpufreq: Don't clear cpufreq_cpu_data and policy list for inactive policies
Now that we can check policy->cpus to find if policy is active or not,
we don't need to clean cpufreq_cpu_data and delete policy from the list
on light weight tear down of policies (like in suspend).

To make it consistent and clean, set cpufreq_cpu_data for all related
CPUs when the policy is first created and clean it only while it is
freed.

Also update cpufreq_cpu_get_raw() to check if cpu is part of
policy->cpus mask, so that we don't end up getting policies for offline
CPUs.

In order to make sure that no users of 'policy' are using an inactive
policy, use cpufreq_cpu_get_raw() instead of directly accessing
cpufreq_cpu_data.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-15 02:32:46 +02:00
Viresh Kumar f963735a3c cpufreq: Create for_each_{in}active_policy()
policy->cpus is cleared unconditionally now on hotplug-out of a CPU and
it can be checked to know if a policy is active or not. Create helper
routines to iterate over all active/inactive policies, based on
policy->cpus field.

Replace all instances of for_each_policy() with for_each_active_policy()
to make them iterate only for active policies. (We haven't made changes
yet to keep inactive policies in the same list, but that will be
followed in a later patch).

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-15 02:26:07 +02:00
Sudeep Holla 1473014502 cpufreq: arm_big_little: remove compile-time dependency on BIG_LITTLE
With the addition of switcher code, there's compile-time dependency on
BIG_LITTLE to get arm_big_little driver compiling on ARM64. Since ARM64
will never add support for bL switcher, it's better to remove the
dependency so that the driver can be reused on ARM64 platforms.

This patch adds stubs to remove BIG_LITTLE dependency in the driver.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-15 01:53:42 +02:00
Joe Konno 0dd23f9425 intel_pstate: set BYT MSR with wrmsrl_on_cpu()
Commit 007bea098b (intel_pstate: Add setting voltage value for
baytrail P states.) introduced byt_set_pstate() with the assumption that
it would always be run by the CPU whose MSR is to be written by it.  It
turns out, however, that is not always the case in practice, so modify
byt_set_pstate() to enforce the MSR write done by it to always happen on
the right CPU.

Fixes: 007bea098b (intel_pstate: Add setting voltage value for baytrail P states.)
Signed-off-by: Joe Konno <joe.konno@intel.com>
Acked-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-12 23:36:26 +02:00
Viresh Kumar 303ae72307 cpufreq: Clear policy->cpus even for the last CPU
We clear policy->cpus mask while CPUs are hotplugged out. We do it for all CPUs
except the last CPU of the policy. I don't remember what the rationale behind
that was, but I couldn't think of anything that will break if we remove this
conditional clearing and always clear policy->cpus.

The benefit we get out of it is, we can know if a policy is active or not by
checking if this field is empty or not. That will be used by later commits.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-07 23:38:35 +02:00
Viresh Kumar bb29ae152e cpufreq: Keep a single path for adding managed CPUs
There are two cases when we may try to add CPUs we're already handling:
 - On boot, the first cpu has marked all policy->cpus managed and so we
   will find policy for all other policy->cpus later on.
 - When a managed cpu is hotplugged out and later brought back in.

Currently, separate paths and checks take care of the two.  While the
first one is detected by testing cpu against 'policy->cpus', the other
one is detected by testing cpu against 'policy->related_cpus'.

We can handle them both via a single path and there is no need to do
special checking for the first one.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
[ rjw: Changelog, comments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-07 23:36:41 +02:00
Viresh Kumar 1b947c904c cpufreq: Throw warning when we try to get policy for an invalid CPU
Simply returning here with an error is not enough. It shouldn't be allowed at
all to try calling cpufreq_cpu_get() for an invalid CPU.

Add a WARN here to make it clear that it wouldn't be acceptable at all.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-07 23:29:57 +02:00
Viresh Kumar 23faf0b743 cpufreq: Merge __cpufreq_add_dev() and cpufreq_add_dev()
cpufreq_add_dev() is an unnecessary wrapper over __cpufreq_add_dev(). Merge
them.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-07 23:28:28 +02:00
Viresh Kumar 50e9c85213 cpufreq: Add doc style comment about cpufreq_cpu_{get|put}()
This clearly states what the code inside these routines is doing and how these
must be used.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-07 23:27:20 +02:00
Doug Smythies 4055fad340 intel_pstate: Add tsc collection and keep previous target pstate
The intel_pstate driver is difficult to debug and investigate without tsc.

Also, it is likely use of tsc, and some version of C0 percentage,
will be re-introdcued in futute.

There have also been occasions where it is desirebale to know, and
confirm, the previous target pstate.

This patch brings back tsc, adds previous target pstate,
and adds both to the trace data collection.

Signed-off-by: Doug Smythies <dsmythies@telus.net>
Acked-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-05 01:08:54 +02:00
Sudeep Holla b904f5cce1 cpufreq: arm_big_little: remove unused cpu-cluster.<n> clock name
The "cpu-cluster.<n>" used to get the cluster clock is not used by any
platform. Moreover __of_clk_get_by_name used in clk_get return error if
the "clock-names" in the DT doesn't match this string. When using DT,
it's not compulsory to specify the clock name unless there are multiple
clock input entries in the consumer.

This patch removes the unused clock string from the driver.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-05 00:55:16 +02:00
Sudeep Holla 0a95e630b4 cpufreq: arm_big_little: check if the frequency is set correctly
The actual frequency is set through "clk_change_rate" which is void
function. If the underlying hardware fails and returns error, the error
is lost in the clk layer. In order to track such failures, we need to
read back the frequency(just the cached value as clk_recalc called after
clk->ops->set_rate gets the frequency)

This patch adds check to see if the frequency is set correctly or if
they were any hardware failures and sends the appropriate errors to the
cpufreq core.

Reviewed-by: Michael Turquette <mike.turquette@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-05 00:55:16 +02:00
Fabian Frederick 03c2299063 cpufreq: pxa: make pxa_freqs arrays const
pxa255_run_freqs and pxa255_turbo_freqs are only read.
This patch updates arrays declaration, find_freq_tables()
and its callsites.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-05 00:49:38 +02:00
Fabian Frederick 52352558d2 cpufreq: pxa: replace typedef pxa_freqs_t by structure
typedef is not really useful here. Replace it by structure
to improve readability. typedef should only be used in some cases.
(See Documentation/CodingStyle Chapter 5 for details).

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-05 00:49:37 +02:00
Borislav Petkov 64df1fdfcc cpufreq: intel_pstate: Fix an annoying !CONFIG_SMP warning
I keep seeing

  drivers/cpufreq/intel_pstate.c: In function ‘intel_pstate_init’:
  drivers/cpufreq/intel_pstate.c:1187:26: warning: initialization from incompatible pointer type
    struct cpuinfo_x86 *c = &boot_cpu_data;

when doing randconfig builds.

This is caused by the fact that when !CONFIG_SMP, asm/processor.h
defines cpu_info to boot_cpu_data and the local variable

  struct cpu_defaults *cpu_info

overshadows it leading to this unfortunate assignment in the
preprocessed source:

 struct cpu_defaults *boot_cpu_data;
 struct cpuinfo_x86 *c = &boot_cpu_data;

Rename the local variable and use static_cpu_has_safe() which alleviates
the need for defining a local cpuinfo_x86 pointer.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-15 23:02:24 +02:00
Kristen Carlson Accardi 6a82ba6d4f intel_pstate: Change the setpoint for Atom params
Change the setpoint for the Baytrail and Cherrytrail CPUs.  This
will cause more aggressive pstate selection and improves
performance on a variety of workloads with little power penalty.

Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-15 22:42:32 +02:00
Dasaratharaman Chandramouli b34ef932d7 intel_pstate: Knights Landing support
1. Add Knights Landing (KNL) CPUID to the list of CPUIDs supported by
    the intel_pstate driver.

 2. Add a new cpu_default structure for KNL since KNL has a slightly
    different mechanism to get turbo pstates from MSRs.

Signed-off-by: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com>
Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
[ rjw: Subject and changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-11 02:13:29 +02:00
Kristen Carlson Accardi 5f97899d78 intel_pstate: remove MSR test
x86_match_cpu will not match our cpuid unless APERF/MPERF flag is
set, so there is no need to do the manual check for this MSR.

Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-11 02:13:28 +02:00
Arnd Bergmann 4492d1a2e9 cpufreq: fix qoriq uniprocessor build
The qoriq-cpufreq driver contains a hack for powerpc to include
asm/smp.h on uniprocessor builds so it can get the hardware CPU
number. On ARM, it does not require this hack, but instead gets
a compile error:

In file included from drivers/cpufreq/qoriq-cpufreq.c:24:0:
arch/arm/include/asm/smp.h:18:3: error: #error "<asm/smp.h> included in non-SMP build"
arch/arm/include/asm/smp.h:21:0: warning: "raw_smp_processor_id" redefined

This adds an #ifdef to mirror the one in its get_cpu_physical_id()
function.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 2f249358ee ("cpufreq: qoriq: rename the driver")
Cc: Tang Yuantian <Yuantian.Tang@freescale.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-11 02:07:28 +02:00
Rafael J. Wysocki 38fc7839ba Merge back earlier cpufreq material for v4.1. 2015-04-10 12:00:36 +02:00
Viresh Kumar c75de0ac07 cpufreq: Schedule work for the first-online CPU on resume
All CPUs leaving the first-online CPU are hotplugged out on suspend and
and cpufreq core stops managing them.

On resume, we need to call cpufreq_update_policy() for this CPU's policy
to make sure its frequency is in sync with cpufreq's cached value, as it
might have got updated by hardware during suspend/resume.

The policies are always added to the top of the policy-list. So, in
normal circumstances, CPU 0's policy will be the last one in the list.
And so the code checks for the last policy.

But there are cases where it will fail. Consider quad-core system, with
policy-per core. If CPU0 is hotplugged out and added back again, the
last policy will be on CPU1 :(

To fix this in a proper way, always look for the policy of the first
online CPU. That way we will be sure that we are calling
cpufreq_update_policy() for the only CPU that wasn't hotplugged out.

Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
Fixes: 2f0aea9363 ("cpufreq: suspend governors on system suspend/hibernate")
Reported-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-03 12:59:47 +02:00
Leo Yan 5acb972fed cpufreq: hisilicon: add acpu driver
Add acpu driver for hisilicon SoC, acpu is application processor
subsystem. Currently the acpu has the coupled clock domain for two
clusters, so this driver will directly use cpufreq-dt driver as
backend.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-02 02:24:54 +02:00
Shilpasri G Bhat 09a972d162 cpufreq: powernv: Report cpu frequency throttling
The power and thermal safety of the system is taken care by an
On-Chip-Controller (OCC) which is real-time subsystem embedded within
the POWER8 processor. OCC continuously monitors the memory and core
temperature, the total system power, state of power supply and fan.

The cpu frequency can be throttled by OCC for the following reasons:
1)If a processor crosses its power and temperature limit then OCC will
  lower its Pmax to reduce the frequency and voltage.
2)If OCC crashes then the system is forced to Psafe frequency.
3)If OCC fails to recover then the kernel is not allowed to do any
  further frequency changes and the chip will remain in Psafe.

The user can see a drop in performance when frequency is throttled and
is unaware of throttling. So detect and report such a condition, so
the user can check the OCC status to reboot the system or check for
power supply or fan failures.

The current status of the core is read from Power Management Status
Register(PMSR) to check if any of the throttling condition is occurred
and the appropriate throttling message is reported.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-04-01 23:02:24 +02:00
Tang Yuantian 2f249358ee cpufreq: qoriq: rename the driver
This driver works on all QorIQ platforms which include
ARM-based cores and PPC-based cores.
Rename it in order to represent better.

Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-18 22:35:16 +01:00
Tang Yuantian a4f207428b cpufreq: qoriq: Make the driver usable on all QorIQ platforms
Freescale introduced new ARM core-based SoCs which support dynamic
frequency switch feature. DFS on new SoCs are compatible with current
PowerPC CoreNet platforms. In order to support those new platforms,
this driver needs to be updated. The main changes include:

1. Changed the names of functions in driver.
2. Added two new functions get_cpu_physical_id() and get_bus_freq().
3. Used a new way to get the CPU mask which share clock wire.

Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-18 22:35:15 +01:00
Linus Torvalds 5b3b5921ba Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal
Pull thermal management fixes from Eduardo Valentin:
 "Specifics:

   - adding Lukasz as maintainer of samsung thermal driver.
   - driver fixes: exynos and int430x.
   - one fix in the exynos cpufreq driver related to cpu cooling (acked
     by cpufreq maintainer).
   - fix default sysfs attributes of cooling devices

  Note: I am sending this pull on Rui's behalf while he fixes issues in his Linux box"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal: Make sysfs attributes of cooling devices default attributes
  Thermal/int340x: Fix memleak for aux trip
  MAINTAINERS: Add entry for SAMSUNG THERMAL DRIVER
  cpufreq: exynos: Use simple approach to asses if cpu cooling can be used
  thermal: exynos: Fix wrong control of power down detection mode for Exynos7
2015-03-06 13:43:33 -08:00
Geert Uytterhoeven 5877b4f467 cpufreq: ppc: Add missing #include <asm/smp.h>
If CONFIG_SMP=n, <linux/smp.h> does not include <asm/smp.h>, causing:

drivers/cpufreq/ppc-corenet-cpufreq.c: In function 'corenet_cpufreq_cpu_init':
drivers/cpufreq/ppc-corenet-cpufreq.c:173:3: error: implicit declaration of function 'get_hard_smp_processor_id' [-Werror=implicit-function-declaration]

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-03-04 14:14:54 +01:00
Lukasz Majewski 0fc83929d0 cpufreq: exynos: Use simple approach to asses if cpu cooling can be used
Commit: e725d26c48 provided possibility to
use device tree to asses if cpu can be used as cooling device. Since the
code was somewhat awkward, simpler approach has been proposed.

Test HW: Exynos 4412 - Odroid U3.

Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2015-03-02 10:04:52 +01:00
Linus Torvalds cd50b70ccd Additional power management and ACPI updates for v3.20-rc1
- Revert a recent ACPI LPSS driver commit that prevented the touchpad
    driver from loading on Dell XPS13 (Jarkko Nikula).
 
  - Make the ACPI LPSS driver disable the I2C controllers and deassert
    SPI host controllers resets at startup on Intel BayTrail and Braswell
    SoCs in case they have been left in wrong states by the platform
    firmware which then may casuse fatal controller driver failures during
    resume from hibernation (Mika Westerberg).
 
  - Make two recently added ACPI EC messages look better (Scot Doyle).
 
  - Reduce the printk level of a recently added debug message related to
    ACPI resources that may become noisy in some cases (Rafael J Wysocki).
 
  - Add a new ACPI backlight blacklist entry for Samsung Series 9
    (900X3C/900X3D/900X3E/900X4C/900X4D) laptops where the native backlight
    interface doesn't work while the ACPI based one does (Jens Reyer).
 
  - Make the PNP sybsystem's core code use __request_region() followed by
    __release_region() instead of __check_region() which then will allow
    us to get rid of the latter as it has no more users (Jakub Sitnicki).
 
  - Fix a build breakage and an issue with two __init functions that may be
    called after initialization in the s3c cpufreq driver (Arnd Bergmann).
 
  - Make the powernv cpuidle driver read target_residency values for idle
    states from a Device Tree (as we have the suitable DT bindings for that
    now) and improve the parsing of the powermgmt DT node in that driver
    (Preeti U Murthy).
 
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Merge tag 'pm+acpi-3.20-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull one more batch of power management and ACPI updates from Rafael Wysocki:
 "These are mostly fixes on top of the previously merged recent PM and
  ACPI material.

  First, one commit that broke the ACPI LPSS (Low-Power Subsystem)
  driver on a Dell box is reverted and there are two stable-candidate
  fixes for that driver.  Another fix cleans up two recently added ACPI
  EC messages that look odd and the printk level of a noisy debug
  message in the core ACPI resources handling code is reduced.

  In addition to that we have two stable-candidate fixes for the s3c
  cpufreq driver, two cpuidle powernv driver updates related to Device
  Trees and a PNP subsystem cleanup that will allow us to get rid of
  some old ugliness going forward.  Also there is a new blacklist entry
  for the ACPI backlight code.

  Specifics:

   - Revert a recent ACPI LPSS driver commit that prevented the touchpad
     driver from loading on Dell XPS13 (Jarkko Nikula).

   - Make the ACPI LPSS driver disable the I2C controllers and deassert
     SPI host controllers resets at startup on Intel BayTrail and
     Braswell SoCs in case they have been left in wrong states by the
     platform firmware which then may casuse fatal controller driver
     failures during resume from hibernation (Mika Westerberg).

   - Make two recently added ACPI EC messages look better (Scot Doyle).

   - Reduce the printk level of a recently added debug message related
     to ACPI resources that may become noisy in some cases (Rafael J
     Wysocki).

   - Add a new ACPI backlight blacklist entry for Samsung Series 9
     (900X3C/900X3D/900X3E/900X4C/900X4D) laptops where the native
     backlight interface doesn't work while the ACPI based one does
     (Jens Reyer).

   - Make the PNP sybsystem's core code use __request_region() followed
     by __release_region() instead of __check_region() which then will
     allow us to get rid of the latter as it has no more users (Jakub
     Sitnicki).

   - Fix a build breakage and an issue with two __init functions that
     may be called after initialization in the s3c cpufreq driver (Arnd
     Bergmann).

   - Make the powernv cpuidle driver read target_residency values for
     idle states from a Device Tree (as we have the suitable DT bindings
     for that now) and improve the parsing of the powermgmt DT node in
     that driver (Preeti U Murthy)"

* tag 'pm+acpi-3.20-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpuidle: powernv: Avoid endianness conversions while parsing DT
  cpufreq: s3c: remove last use of resume_clocks callback
  cpufreq: s3c: remove incorrect __init annotations
  ACPI / LPSS: Deassert resets for SPI host controllers on Braswell
  ACPI / LPSS: Always disable I2C host controllers
  ACPI / resources: Change pr_info() to pr_debug() for debug information
  ACPI / video: Disable native backlight on Samsung Series 9 laptops
  cpuidle: powernv: Read target_residency value of idle states from DT if available
  Revert "ACPI / LPSS: Remove non-existing clock control from Intel Lynxpoint I2C"
  ACPI / EC: Remove non-standard log emphasis
  PNP: Switch from __check_region() to __request_region()
2015-02-21 13:40:41 -08:00
Linus Torvalds 18a8d49973 The clock framework changes for 3.20 contain the usual driver additions,
enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based
 devices. Additionaly the framework core underwent a bit of surgery with
 two major changes. The boundary between the clock core and clock
 providers (e.g clock drivers) is now more well defined with dedicated
 provider helper functions. struct clk no longer maps 1:1 with the
 hardware clock but is a true per-user cookie which helps us tracker
 users of hardware clocks and debug bad behavior. The second major change
 is the addition of rate constraints for clocks. Rate ranges are now
 supported which are analogous to the voltage ranges in the regulator
 framework. Unfortunately these changes to the core created some
 breakeage. We think we fixed it all up but for this reason there are
 lots of last minute commits trying to undo the damage.
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Merge tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux

Pull clock framework updates from Mike Turquette:
 "The clock framework changes contain the usual driver additions,
  enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based
  devices.

  Additionally the framework core underwent a bit of surgery with two
  major changes:

   - The boundary between the clock core and clock providers (e.g clock
     drivers) is now more well defined with dedicated provider helper
     functions.  struct clk no longer maps 1:1 with the hardware clock
     but is a true per-user cookie which helps us tracker users of
     hardware clocks and debug bad behavior.

   - The addition of rate constraints for clocks.  Rate ranges are now
     supported which are analogous to the voltage ranges in the
     regulator framework.

  Unfortunately these changes to the core created some breakeage.  We
  think we fixed it all up but for this reason there are lots of last
  minute commits trying to undo the damage"

* tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux: (113 commits)
  clk: Only recalculate the rate if needed
  Revert "clk: mxs: Fix invalid 32-bit access to frac registers"
  clk: qoriq: Add support for the platform PLL
  powerpc/corenet: Enable CLK_QORIQ
  clk: Replace explicit clk assignment with __clk_hw_set_clk
  clk: Add __clk_hw_set_clk helper function
  clk: Don't dereference parent clock if is NULL
  MIPS: Alchemy: Remove bogus args from alchemy_clk_fgcs_detr
  clkdev: Always allocate a struct clk and call __clk_get() w/ CCF
  clk: shmobile: div6: Avoid division by zero in .round_rate()
  clk: mxs: Fix invalid 32-bit access to frac registers
  clk: omap: compile legacy omap3 clocks conditionally
  clkdev: Export clk_register_clkdev
  clk: Add rate constraints to clocks
  clk: remove clk-private.h
  pci: xgene: do not use clk-private.h
  arm: omap2+ remove dead clock code
  clk: Make clk API return per-user struct clk instances
  clk: tegra: Define PLLD_DSI and remove dsia(b)_mux
  clk: tegra: Add support for the Tegra132 CAR IP block
  ...
2015-02-21 12:30:30 -08:00
Rafael J. Wysocki 3466b547e3 Merge branches 'pnp', 'pm-cpuidle' and 'pm-cpufreq'
* pnp:
  PNP: Switch from __check_region() to __request_region()

* pm-cpuidle:
  cpuidle: powernv: Avoid endianness conversions while parsing DT
  cpuidle: powernv: Read target_residency value of idle states from DT if available

* pm-cpufreq:
  cpufreq: s3c: remove last use of resume_clocks callback
  cpufreq: s3c: remove incorrect __init annotations
2015-02-21 04:29:16 +01:00
Linus Torvalds 3d883483dc Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal
Pull more thermal managament updates from Zhang Rui:
 "Specifics:

   - Exynos thermal driver refactoring.  Several cleanups, code
     optimization, unused symbols removal, and unused feature removal in
     Exynos thermal driver.  Thanks Lukasz for this effort.

   - Exynos thermal driver support to OF thermal.  After the code
     refactoring, the driver earned the support to OF thermal.  Chip
     thermal data were moved from driver code to DTS, reducing the code
     footprint.  Thanks Lukasz for this.

   - After receiving the OF thermal support, the exynos thermal driver
     now must allow modular build.  Thanks Arnd for detecting, reporting
     and fixing this.

   - Exynos thermal driver support to Exynos 7 SoC.  Thanks Abhilash for
     this.

   - Accurate temperature reporting on Rockchip thermal driver, thanks
     to Caesar.

   - Fix on how OF thermal enables its zones, thanks Lukasz for fixing.

   - Fixes in OF thermal examples under Documentation/.  Thanks Srinivas
     for fixing"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal: exynos: Add TMU support for Exynos7 SoC
  dts: Documentation: Add documentation for Exynos7 SoC thermal bindings
  cpufreq: exynos: allow modular build
  thermal: Fix examples in DT documentation
  thermal: exynos: Correct sanity check at exynos_report_trigger() function
  thermal: Kconfig: Remove config for not used EXYNOS_THERMAL_CORE
  thermal: exynos: Remove exynos_tmu_data.c file
  thermal: rockchip: make temperature reporting much more accurate
  thermal: exynos: Remove exynos_thermal_common.[c|h] files
  thermal: samsung: core: Exynos TMU rework to use device tree for configuration
  dts: Documentation: Update exynos-thermal.txt example for Exynos5440
  dts: Documentation: Extending documentation entry for exynos-thermal
  cpufreq: exynos: Use device tree to determine if cpufreq cooling should be registered
  thermal: exynos: Modify exynos thermal code to use device tree for cpu cooling configuration
  thermal: exynos: Provide thermal_exynos.h file to be included in device tree files
  thermal: exynos: cosmetic: Correct comment format
  thermal: of: Enable thermal_zoneX when sensor is correctly added
2015-02-19 17:51:22 -08:00
Arnd Bergmann 67fadaa276 cpufreq: s3c: remove last use of resume_clocks callback
Commit 32726d2d55 ("ARM: SAMSUNG: Remove legacy clock code")
already removed the callback pointer, but there was one remaining
user:

drivers/cpufreq/s3c24xx-cpufreq.c: In function 's3c_cpufreq_resume_clocks':
drivers/cpufreq/s3c24xx-cpufreq.c:149:14: error: 'struct s3c_cpufreq_info' has no member named 'resume_clocks'
  cpu_cur.info->resume_clocks();
              ^

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 32726d2d55 ("ARM: SAMSUNG: Remove legacy clock code")
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 3.17+ <stable@vger.kernel.org> # v3.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-19 06:36:53 +01:00
Arnd Bergmann 61882b6317 cpufreq: s3c: remove incorrect __init annotations
The two functions s3c2416_cpufreq_driver_init and s3c_cpufreq_register
are marked init but are called from a context that might be run after
the __init sections are discarded, as the compiler points out:

WARNING: vmlinux.o(.data+0x1ad9dc): Section mismatch in reference from the variable s3c2416_cpufreq_driver to the function .init.text:s3c2416_cpufreq_driver_init()
WARNING: drivers/built-in.o(.text+0x35b5dc): Section mismatch in reference from the function s3c2410a_cpufreq_add() to the function .init.text:s3c_cpufreq_register()

This removes the __init markings.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-19 06:36:53 +01:00
Rafael J. Wysocki c7fb90dfbe Merge branches 'pm-cpufreq', 'pm-cpuidle', 'pm-devfreq', 'pm-opp' and 'pm-tools'
* pm-cpufreq:
  cpufreq: speedstep-smi: enable interrupts when waiting

* pm-cpuidle:
  intel_idle: support additional Broadwell model

* pm-devfreq:
  PM / devfreq: event: testing the wrong variable

* pm-opp:
  PM / OPP / clk: Remove unnecessary OOM message

* pm-tools:
  tools/power turbostat: support additional Broadwell model
  tools/power turbostat: update parameters, documentation
  tools/power turbostat: Skip printing disabled package C-states
2015-02-13 21:39:06 +01:00
Mikulas Patocka d4d4eda237 cpufreq: speedstep-smi: enable interrupts when waiting
On Dell Latitude C600 laptop with Pentium 3 850MHz processor, the
speedstep-smi driver sometimes loads and sometimes doesn't load with
"change to state X failed" message.

The hardware sometimes refuses to change frequency and in this case, we
need to retry later. I found out that we need to enable interrupts while
waiting. When we enable interrupts, the hardware blockage that prevents
frequency transition resolves and the transition is possible. With
disabled interrupts, the blockage doesn't resolve (no matter how long do
we wait). The exact reasons for this hardware behavior are unknown.

This patch enables interrupts in the function speedstep_set_state that can
be called with disabled interrupts. However, this function is called with
disabled interrupts only from speedstep_get_freqs, so it shouldn't cause
any problem.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com
Cc: All applicable <stable@vger.kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-12 02:02:52 +01:00