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* pm-cpufreq: (28 commits)
  MAINTAINERS: cpufreq: add bmips-cpufreq.c
  cpufreq: CPPC: add ACPI_PROCESSOR dependency
  cpufreq: make ti-cpufreq explicitly non-modular
  cpufreq: Do not clear real_cpus mask on policy init
  cpufreq: dt: Don't use generic platdev driver for ti-cpufreq platforms
  cpufreq: ti: Add cpufreq driver to determine available OPPs at runtime
  Documentation: dt: add bindings for ti-cpufreq
  cpufreq: qoriq: Don't look at clock implementation details
  cpufreq: qoriq: add ARM64 SoCs support
  cpufreq: brcmstb-avs-cpufreq: remove unnecessary platform_set_drvdata()
  cpufreq: s3c2416: double free on driver init error path
  MIPS: BMIPS: enable CPUfreq
  cpufreq: bmips-cpufreq: CPUfreq driver for Broadcom's BMIPS SoCs
  BMIPS: Enable prerequisites for CPUfreq in MIPS Kconfig.
  MIPS: BMIPS: Update defconfig
  cpufreq: Fix typos in comments
  cpufreq: intel_pstate: Calculate guaranteed performance for HWP
  cpufreq: intel_pstate: Make HWP limits compatible with legacy
  cpufreq: intel_pstate: Lower frequency than expected under no_turbo
  cpufreq: intel_pstate: Operation mode control from sysfs
  ...
This commit is contained in:
Rafael J. Wysocki 2017-02-20 14:23:00 +01:00
commit f6cbe34f52
36 changed files with 1398 additions and 524 deletions
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24
Documentation/cpu-freq/core.txt
View File

@ -8,6 +8,8 @@
Dominik Brodowski <linux@brodo.de>
David Kimdon <dwhedon@debian.org>
Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar <viresh.kumar@linaro.org>
@ -36,10 +38,11 @@ speed limits (like LCD drivers on ARM architecture). Additionally, the
kernel "constant" loops_per_jiffy is updated on frequency changes
here.
Reference counting is done by cpufreq_get_cpu and cpufreq_put_cpu,
which make sure that the cpufreq processor driver is correctly
registered with the core, and will not be unloaded until
cpufreq_put_cpu is called.
Reference counting of the cpufreq policies is done by cpufreq_cpu_get
and cpufreq_cpu_put, which make sure that the cpufreq driver is
correctly registered with the core, and will not be unloaded until
cpufreq_put_cpu is called. That also ensures that the respective cpufreq
policy doesn't get freed while being used.
2. CPUFreq notifiers
====================
@ -69,18 +72,16 @@ CPUFreq policy notifier is called twice for a policy transition:
The phase is specified in the second argument to the notifier.
The third argument, a void *pointer, points to a struct cpufreq_policy
consisting of five values: cpu, min, max, policy and max_cpu_freq. min
and max are the lower and upper frequencies (in kHz) of the new
policy, policy the new policy, cpu the number of the affected CPU; and
max_cpu_freq the maximum supported CPU frequency. This value is given
for informational purposes only.
consisting of several values, including min, max (the lower and upper
frequencies (in kHz) of the new policy).
2.2 CPUFreq transition notifiers
--------------------------------
These are notified twice when the CPUfreq driver switches the CPU core
frequency and this change has any external implications.
These are notified twice for each online CPU in the policy, when the
CPUfreq driver switches the CPU core frequency and this change has no
any external implications.
The second argument specifies the phase - CPUFREQ_PRECHANGE or
CPUFREQ_POSTCHANGE.
@ -90,6 +91,7 @@ values:
cpu - number of the affected CPU
old - old frequency
new - new frequency
flags - flags of the cpufreq driver
3. CPUFreq Table Generation with Operating Performance Point (OPP)
==================================================================

171
Documentation/cpu-freq/cpu-drivers.txt
View File

@ -9,6 +9,8 @@
Dominik Brodowski <linux@brodo.de>
Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar <viresh.kumar@linaro.org>
@ -49,49 +51,65 @@ using cpufreq_register_driver()
What shall this struct cpufreq_driver contain?
cpufreq_driver.name - The name of this driver.
.name - The name of this driver.
cpufreq_driver.init - A pointer to the per-CPU initialization
function.
.init - A pointer to the per-policy initialization function.
cpufreq_driver.verify - A pointer to a "verification" function.
.verify - A pointer to a "verification" function.
cpufreq_driver.setpolicy _or_
cpufreq_driver.target/
target_index - See below on the differences.
.setpolicy _or_ .fast_switch _or_ .target _or_ .target_index - See
below on the differences.
And optionally
cpufreq_driver.exit - A pointer to a per-CPU cleanup
function called during CPU_POST_DEAD
phase of cpu hotplug process.
.flags - Hints for the cpufreq core.
cpufreq_driver.stop_cpu - A pointer to a per-CPU stop function
called during CPU_DOWN_PREPARE phase of
cpu hotplug process.
.driver_data - cpufreq driver specific data.
cpufreq_driver.resume - A pointer to a per-CPU resume function
which is called with interrupts disabled
and _before_ the pre-suspend frequency
and/or policy is restored by a call to
->target/target_index or ->setpolicy.
.resolve_freq - Returns the most appropriate frequency for a target
frequency. Doesn't change the frequency though.
cpufreq_driver.attr - A pointer to a NULL-terminated list of
"struct freq_attr" which allow to
export values to sysfs.
.get_intermediate and target_intermediate - Used to switch to stable
frequency while changing CPU frequency.
cpufreq_driver.get_intermediate
and target_intermediate Used to switch to stable frequency while
changing CPU frequency.
.get - Returns current frequency of the CPU.
.bios_limit - Returns HW/BIOS max frequency limitations for the CPU.
.exit - A pointer to a per-policy cleanup function called during
CPU_POST_DEAD phase of cpu hotplug process.
.stop_cpu - A pointer to a per-policy stop function called during
CPU_DOWN_PREPARE phase of cpu hotplug process.
.suspend - A pointer to a per-policy suspend function which is called
with interrupts disabled and _after_ the governor is stopped for the
policy.
.resume - A pointer to a per-policy resume function which is called
with interrupts disabled and _before_ the governor is started again.
.ready - A pointer to a per-policy ready function which is called after
the policy is fully initialized.
.attr - A pointer to a NULL-terminated list of "struct freq_attr" which
allow to export values to sysfs.
.boost_enabled - If set, boost frequencies are enabled.
.set_boost - A pointer to a per-policy function to enable/disable boost
frequencies.
1.2 Per-CPU Initialization
--------------------------
Whenever a new CPU is registered with the device model, or after the
cpufreq driver registers itself, the per-CPU initialization function
cpufreq_driver.init is called. It takes a struct cpufreq_policy
*policy as argument. What to do now?
cpufreq driver registers itself, the per-policy initialization function
cpufreq_driver.init is called if no cpufreq policy existed for the CPU.
Note that the .init() and .exit() routines are called only once for the
policy and not for each CPU managed by the policy. It takes a struct
cpufreq_policy *policy as argument. What to do now?
If necessary, activate the CPUfreq support on your CPU.
@ -117,47 +135,45 @@ policy->governor must contain the "default policy" for
cpufreq_driver.setpolicy or
cpufreq_driver.target/target_index is called
with these values.
policy->cpus Update this with the masks of the
(online + offline) CPUs that do DVFS
along with this CPU (i.e. that share
clock/voltage rails with it).
For setting some of these values (cpuinfo.min[max]_freq, policy->min[max]), the
frequency table helpers might be helpful. See the section 2 for more information
on them.
SMP systems normally have same clock source for a group of cpus. For these the
.init() would be called only once for the first online cpu. Here the .init()
routine must initialize policy->cpus with mask of all possible cpus (Online +
Offline) that share the clock. Then the core would copy this mask onto
policy->related_cpus and will reset policy->cpus to carry only online cpus.
1.3 verify
------------
----------
When the user decides a new policy (consisting of
"policy,governor,min,max") shall be set, this policy must be validated
so that incompatible values can be corrected. For verifying these
values, a frequency table helper and/or the
cpufreq_verify_within_limits(struct cpufreq_policy *policy, unsigned
int min_freq, unsigned int max_freq) function might be helpful. See
section 2 for details on frequency table helpers.
values cpufreq_verify_within_limits(struct cpufreq_policy *policy,
unsigned int min_freq, unsigned int max_freq) function might be helpful.
See section 2 for details on frequency table helpers.
You need to make sure that at least one valid frequency (or operating
range) is within policy->min and policy->max. If necessary, increase
policy->max first, and only if this is no solution, decrease policy->min.
1.4 target/target_index or setpolicy?
----------------------------
1.4 target or target_index or setpolicy or fast_switch?
-------------------------------------------------------
Most cpufreq drivers or even most cpu frequency scaling algorithms
only allow the CPU to be set to one frequency. For these, you use the
->target/target_index call.
only allow the CPU frequency to be set to predefined fixed values. For
these, you use the ->target(), ->target_index() or ->fast_switch()
callbacks.
Some cpufreq-capable processors switch the frequency between certain
limits on their own. These shall use the ->setpolicy call
Some cpufreq capable processors switch the frequency between certain
limits on their own. These shall use the ->setpolicy() callback.
1.5. target/target_index
-------------
------------------------
The target_index call has two arguments: struct cpufreq_policy *policy,
and unsigned int index (into the exposed frequency table).
@ -186,9 +202,20 @@ actual frequency must be determined using the following rules:
Here again the frequency table helper might assist you - see section 2
for details.
1.6. fast_switch
----------------
1.6 setpolicy
---------------
This function is used for frequency switching from scheduler's context.
Not all drivers are expected to implement it, as sleeping from within
this callback isn't allowed. This callback must be highly optimized to
do switching as fast as possible.
This function has two arguments: struct cpufreq_policy *policy and
unsigned int target_frequency.
1.7 setpolicy
-------------
The setpolicy call only takes a struct cpufreq_policy *policy as
argument. You need to set the lower limit of the in-processor or
@ -198,7 +225,7 @@ setting when policy->policy is CPUFREQ_POLICY_PERFORMANCE, and a
powersaving-oriented setting when CPUFREQ_POLICY_POWERSAVE. Also check
the reference implementation in drivers/cpufreq/longrun.c
1.7 get_intermediate and target_intermediate
1.8 get_intermediate and target_intermediate
--------------------------------------------
Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION unset.
@ -222,42 +249,36 @@ failures as core would send notifications for that.
As most cpufreq processors only allow for being set to a few specific
frequencies, a "frequency table" with some functions might assist in
some work of the processor driver. Such a "frequency table" consists
of an array of struct cpufreq_frequency_table entries, with any value in
"driver_data" you want to use, and the corresponding frequency in
"frequency". At the end of the table, you need to add a
cpufreq_frequency_table entry with frequency set to CPUFREQ_TABLE_END. And
if you want to skip one entry in the table, set the frequency to
CPUFREQ_ENTRY_INVALID. The entries don't need to be in ascending
order.
some work of the processor driver. Such a "frequency table" consists of
an array of struct cpufreq_frequency_table entries, with driver specific
values in "driver_data", the corresponding frequency in "frequency" and
flags set. At the end of the table, you need to add a
cpufreq_frequency_table entry with frequency set to CPUFREQ_TABLE_END.
And if you want to skip one entry in the table, set the frequency to
CPUFREQ_ENTRY_INVALID. The entries don't need to be in sorted in any
particular order, but if they are cpufreq core will do DVFS a bit
quickly for them as search for best match is faster.
By calling cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table);
the cpuinfo.min_freq and cpuinfo.max_freq values are detected, and
policy->min and policy->max are set to the same values. This is
helpful for the per-CPU initialization stage.
By calling cpufreq_table_validate_and_show(), the cpuinfo.min_freq and
cpuinfo.max_freq values are detected, and policy->min and policy->max
are set to the same values. This is helpful for the per-CPU
initialization stage.
int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table);
assures that at least one valid frequency is within policy->min and
policy->max, and all other criteria are met. This is helpful for the
->verify call.
cpufreq_frequency_table_verify() assures that at least one valid
frequency is within policy->min and policy->max, and all other criteria
are met. This is helpful for the ->verify call.
int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation);
is the corresponding frequency table helper for the ->target
stage. Just pass the values to this function, and this function
returns the number of the frequency table entry which contains
the frequency the CPU shall be set to.
cpufreq_frequency_table_target() is the corresponding frequency table
helper for the ->target stage. Just pass the values to this function,
and this function returns the of the frequency table entry which
contains the frequency the CPU shall be set to.
The following macros can be used as iterators over cpufreq_frequency_table:
cpufreq_for_each_entry(pos, table) - iterates over all entries of frequency
table.
cpufreq-for_each_valid_entry(pos, table) - iterates over all entries,
cpufreq_for_each_valid_entry(pos, table) - iterates over all entries,
excluding CPUFREQ_ENTRY_INVALID frequencies.
Use arguments "pos" - a cpufreq_frequency_table * as a loop cursor and
"table" - the cpufreq_frequency_table * you want to iterate over.

24
Documentation/cpu-freq/cpufreq-stats.txt
View File

@ -34,10 +34,10 @@ cpufreq stats provides following statistics (explained in detail below).
- total_trans
- trans_table
All the statistics will be from the time the stats driver has been inserted
to the time when a read of a particular statistic is done. Obviously, stats
driver will not have any information about the frequency transitions before
the stats driver insertion.
All the statistics will be from the time the stats driver has been inserted
(or the time the stats were reset) to the time when a read of a particular
statistic is done. Obviously, stats driver will not have any information
about the frequency transitions before the stats driver insertion.
--------------------------------------------------------------------------------
<mysystem>:/sys/devices/system/cpu/cpu0/cpufreq/stats # ls -l
@ -110,25 +110,13 @@ Config Main Menu
CPU Frequency scaling --->
[*] CPU Frequency scaling
[*] CPU frequency translation statistics
[*] CPU frequency translation statistics details
"CPU Frequency scaling" (CONFIG_CPU_FREQ) should be enabled to configure
cpufreq-stats.
"CPU frequency translation statistics" (CONFIG_CPU_FREQ_STAT) provides the
basic statistics which includes time_in_state and total_trans.
statistics which includes time_in_state, total_trans and trans_table.
"CPU frequency translation statistics details" (CONFIG_CPU_FREQ_STAT_DETAILS)
provides fine grained cpufreq stats by trans_table. The reason for having a
separate config option for trans_table is:
- trans_table goes against the traditional /sysfs rule of one value per
interface. It provides a whole bunch of value in a 2 dimensional matrix
form.
Once these two options are enabled and your CPU supports cpufrequency, you
Once this option is enabled and your CPU supports cpufrequency, you
will be able to see the CPU frequency statistics in /sysfs.

304
Documentation/cpu-freq/governors.txt
View File

@ -10,6 +10,8 @@
Dominik Brodowski <linux@brodo.de>
some additions and corrections by Nico Golde <nico@ngolde.de>
Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar <viresh.kumar@linaro.org>
@ -28,32 +30,27 @@ Contents:
2.3 Userspace
2.4 Ondemand
2.5 Conservative
2.6 Schedutil
3. The Governor Interface in the CPUfreq Core
4. References
1. What Is A CPUFreq Governor?
==============================
Most cpufreq drivers (except the intel_pstate and longrun) or even most
cpu frequency scaling algorithms only offer the CPU to be set to one
frequency. In order to offer dynamic frequency scaling, the cpufreq
core must be able to tell these drivers of a "target frequency". So
these specific drivers will be transformed to offer a "->target/target_index"
call instead of the existing "->setpolicy" call. For "longrun", all
stays the same, though.
cpu frequency scaling algorithms only allow the CPU frequency to be set
to predefined fixed values. In order to offer dynamic frequency
scaling, the cpufreq core must be able to tell these drivers of a
"target frequency". So these specific drivers will be transformed to
offer a "->target/target_index/fast_switch()" call instead of the
"->setpolicy()" call. For set_policy drivers, all stays the same,
though.
How to decide what frequency within the CPUfreq policy should be used?
That's done using "cpufreq governors". Two are already in this patch
-- they're the already existing "powersave" and "performance" which
set the frequency statically to the lowest or highest frequency,
respectively. At least two more such governors will be ready for
addition in the near future, but likely many more as there are various
different theories and models about dynamic frequency scaling
around. Using such a generic interface as cpufreq offers to scaling
governors, these can be tested extensively, and the best one can be
selected for each specific use.
That's done using "cpufreq governors".
Basically, it's the following flow graph:
@ -71,7 +68,7 @@ CPU can be set to switch independently | CPU can only be set
/ the limits of policy->{min,max}
/ \
/ \
Using the ->setpolicy call, Using the ->target/target_index call,
Using the ->setpolicy call, Using the ->target/target_index/fast_switch call,
the limits and the the frequency closest
"policy" is set. to target_freq is set.
It is assured that it
@ -109,114 +106,159 @@ directory.
2.4 Ondemand
------------
The CPUfreq governor "ondemand" sets the CPU depending on the
current usage. To do this the CPU must have the capability to
switch the frequency very quickly. There are a number of sysfs file
accessible parameters:
The CPUfreq governor "ondemand" sets the CPU frequency depending on the
current system load. Load estimation is triggered by the scheduler
through the update_util_data->func hook; when triggered, cpufreq checks
the CPU-usage statistics over the last period and the governor sets the
CPU accordingly. The CPU must have the capability to switch the
frequency very quickly.
sampling_rate: measured in uS (10^-6 seconds), this is how often you
want the kernel to look at the CPU usage and to make decisions on
what to do about the frequency. Typically this is set to values of
around '10000' or more. It's default value is (cmp. with users-guide.txt):
transition_latency * 1000
Be aware that transition latency is in ns and sampling_rate is in us, so you
get the same sysfs value by default.
Sampling rate should always get adjusted considering the transition latency
To set the sampling rate 750 times as high as the transition latency
in the bash (as said, 1000 is default), do:
echo `$(($(cat cpuinfo_transition_latency) * 750 / 1000)) \
>ondemand/sampling_rate
Sysfs files:
sampling_rate_min:
The sampling rate is limited by the HW transition latency:
transition_latency * 100
Or by kernel restrictions:
If CONFIG_NO_HZ_COMMON is set, the limit is 10ms fixed.
If CONFIG_NO_HZ_COMMON is not set or nohz=off boot parameter is used, the
limits depend on the CONFIG_HZ option:
HZ=1000: min=20000us (20ms)
HZ=250: min=80000us (80ms)
HZ=100: min=200000us (200ms)
The highest value of kernel and HW latency restrictions is shown and
used as the minimum sampling rate.
* sampling_rate:
up_threshold: defines what the average CPU usage between the samplings
of 'sampling_rate' needs to be for the kernel to make a decision on
whether it should increase the frequency. For example when it is set
to its default value of '95' it means that between the checking
intervals the CPU needs to be on average more than 95% in use to then
decide that the CPU frequency needs to be increased.
Measured in uS (10^-6 seconds), this is how often you want the kernel
to look at the CPU usage and to make decisions on what to do about the
frequency. Typically this is set to values of around '10000' or more.
It's default value is (cmp. with users-guide.txt): transition_latency
* 1000. Be aware that transition latency is in ns and sampling_rate
is in us, so you get the same sysfs value by default. Sampling rate
should always get adjusted considering the transition latency to set
the sampling rate 750 times as high as the transition latency in the
bash (as said, 1000 is default), do:
ignore_nice_load: this parameter takes a value of '0' or '1'. When
set to '0' (its default), all processes are counted towards the
'cpu utilisation' value. When set to '1', the processes that are
run with a 'nice' value will not count (and thus be ignored) in the
overall usage calculation. This is useful if you are running a CPU
intensive calculation on your laptop that you do not care how long it
takes to complete as you can 'nice' it and prevent it from taking part
in the deciding process of whether to increase your CPU frequency.
$ echo `$(($(cat cpuinfo_transition_latency) * 750 / 1000)) > ondemand/sampling_rate
sampling_down_factor: this parameter controls the rate at which the
kernel makes a decision on when to decrease the frequency while running
at top speed. When set to 1 (the default) decisions to reevaluate load
are made at the same interval regardless of current clock speed. But
when set to greater than 1 (e.g. 100) it acts as a multiplier for the
scheduling interval for reevaluating load when the CPU is at its top
speed due to high load. This improves performance by reducing the overhead
of load evaluation and helping the CPU stay at its top speed when truly
busy, rather than shifting back and forth in speed. This tunable has no
effect on behavior at lower speeds/lower CPU loads.
* sampling_rate_min:
powersave_bias: this parameter takes a value between 0 to 1000. It
defines the percentage (times 10) value of the target frequency that
will be shaved off of the target. For example, when set to 100 -- 10%,
when ondemand governor would have targeted 1000 MHz, it will target
1000 MHz - (10% of 1000 MHz) = 900 MHz instead. This is set to 0
(disabled) by default.
When AMD frequency sensitivity powersave bias driver --
drivers/cpufreq/amd_freq_sensitivity.c is loaded, this parameter
defines the workload frequency sensitivity threshold in which a lower
frequency is chosen instead of ondemand governor's original target.
The frequency sensitivity is a hardware reported (on AMD Family 16h
Processors and above) value between 0 to 100% that tells software how
the performance of the workload running on a CPU will change when
frequency changes. A workload with sensitivity of 0% (memory/IO-bound)
will not perform any better on higher core frequency, whereas a
workload with sensitivity of 100% (CPU-bound) will perform better
higher the frequency. When the driver is loaded, this is set to 400
by default -- for CPUs running workloads with sensitivity value below
40%, a lower frequency is chosen. Unloading the driver or writing 0
will disable this feature.
The sampling rate is limited by the HW transition latency:
transition_latency * 100
Or by kernel restrictions:
- If CONFIG_NO_HZ_COMMON is set, the limit is 10ms fixed.
- If CONFIG_NO_HZ_COMMON is not set or nohz=off boot parameter is
used, the limits depend on the CONFIG_HZ option:
HZ=1000: min=20000us (20ms)
HZ=250: min=80000us (80ms)
HZ=100: min=200000us (200ms)
The highest value of kernel and HW latency restrictions is shown and
used as the minimum sampling rate.
* up_threshold:
This defines what the average CPU usage between the samplings of
'sampling_rate' needs to be for the kernel to make a decision on
whether it should increase the frequency. For example when it is set
to its default value of '95' it means that between the checking
intervals the CPU needs to be on average more than 95% in use to then
decide that the CPU frequency needs to be increased.
* ignore_nice_load:
This parameter takes a value of '0' or '1'. When set to '0' (its
default), all processes are counted towards the 'cpu utilisation'
value. When set to '1', the processes that are run with a 'nice'
value will not count (and thus be ignored) in the overall usage
calculation. This is useful if you are running a CPU intensive
calculation on your laptop that you do not care how long it takes to
complete as you can 'nice' it and prevent it from taking part in the
deciding process of whether to increase your CPU frequency.
* sampling_down_factor:
This parameter controls the rate at which the kernel makes a decision
on when to decrease the frequency while running at top speed. When set
to 1 (the default) decisions to reevaluate load are made at the same
interval regardless of current clock speed. But when set to greater
than 1 (e.g. 100) it acts as a multiplier for the scheduling interval
for reevaluating load when the CPU is at its top speed due to high
load. This improves performance by reducing the overhead of load
evaluation and helping the CPU stay at its top speed when truly busy,
rather than shifting back and forth in speed. This tunable has no
effect on behavior at lower speeds/lower CPU loads.
* powersave_bias:
This parameter takes a value between 0 to 1000. It defines the
percentage (times 10) value of the target frequency that will be
shaved off of the target. For example, when set to 100 -- 10%, when
ondemand governor would have targeted 1000 MHz, it will target
1000 MHz - (10% of 1000 MHz) = 900 MHz instead. This is set to 0
(disabled) by default.
When AMD frequency sensitivity powersave bias driver --
drivers/cpufreq/amd_freq_sensitivity.c is loaded, this parameter
defines the workload frequency sensitivity threshold in which a lower
frequency is chosen instead of ondemand governor's original target.
The frequency sensitivity is a hardware reported (on AMD Family 16h
Processors and above) value between 0 to 100% that tells software how
the performance of the workload running on a CPU will change when
frequency changes. A workload with sensitivity of 0% (memory/IO-bound)
will not perform any better on higher core frequency, whereas a
workload with sensitivity of 100% (CPU-bound) will perform better
higher the frequency. When the driver is loaded, this is set to 400 by
default -- for CPUs running workloads with sensitivity value below
40%, a lower frequency is chosen. Unloading the driver or writing 0
will disable this feature.
2.5 Conservative
----------------
The CPUfreq governor "conservative", much like the "ondemand"
governor, sets the CPU depending on the current usage. It differs in
behaviour in that it gracefully increases and decreases the CPU speed
rather than jumping to max speed the moment there is any load on the
CPU. This behaviour more suitable in a battery powered environment.
The governor is tweaked in the same manner as the "ondemand" governor
through sysfs with the addition of:
governor, sets the CPU frequency depending on the current usage. It
differs in behaviour in that it gracefully increases and decreases the
CPU speed rather than jumping to max speed the moment there is any load
on the CPU. This behaviour is more suitable in a battery powered
environment. The governor is tweaked in the same manner as the
"ondemand" governor through sysfs with the addition of:
freq_step: this describes what percentage steps the cpu freq should be
increased and decreased smoothly by. By default the cpu frequency will
increase in 5% chunks of your maximum cpu frequency. You can change this
value to anywhere between 0 and 100 where '0' will effectively lock your
CPU at a speed regardless of its load whilst '100' will, in theory, make
it behave identically to the "ondemand" governor.
* freq_step:
down_threshold: same as the 'up_threshold' found for the "ondemand"
governor but for the opposite direction. For example when set to its
default value of '20' it means that if the CPU usage needs to be below
20% between samples to have the frequency decreased.
This describes what percentage steps the cpu freq should be increased
and decreased smoothly by. By default the cpu frequency will increase
in 5% chunks of your maximum cpu frequency. You can change this value
to anywhere between 0 and 100 where '0' will effectively lock your CPU
at a speed regardless of its load whilst '100' will, in theory, make
it behave identically to the "ondemand" governor.
* down_threshold:
Same as the 'up_threshold' found for the "ondemand" governor but for
the opposite direction. For example when set to its default value of
'20' it means that if the CPU usage needs to be below 20% between
samples to have the frequency decreased.
* sampling_down_factor:
Similar functionality as in "ondemand" governor. But in
"conservative", it controls the rate at which the kernel makes a
decision on when to decrease the frequency while running in any speed.
Load for frequency increase is still evaluated every sampling rate.
2.6 Schedutil
-------------
The "schedutil" governor aims at better integration with the Linux
kernel scheduler. Load estimation is achieved through the scheduler's
Per-Entity Load Tracking (PELT) mechanism, which also provides
information about the recent load [1]. This governor currently does
load based DVFS only for tasks managed by CFS. RT and DL scheduler tasks
are always run at the highest frequency. Unlike all the other
governors, the code is located under the kernel/sched/ directory.
Sysfs files:
* rate_limit_us:
This contains a value in microseconds. The governor waits for
rate_limit_us time before reevaluating the load again, after it has
evaluated the load once.
For an in-depth comparison with the other governors refer to [2].
sampling_down_factor: similar functionality as in "ondemand" governor.
But in "conservative", it controls the rate at which the kernel makes
a decision on when to decrease the frequency while running in any
speed. Load for frequency increase is still evaluated every
sampling rate.
3. The Governor Interface in the CPUfreq Core
=============================================
@ -225,26 +267,10 @@ A new governor must register itself with the CPUfreq core using
"cpufreq_register_governor". The struct cpufreq_governor, which has to
be passed to that function, must contain the following values:
governor->name - A unique name for this governor
governor->governor - The governor callback function
governor->owner - .THIS_MODULE for the governor module (if
appropriate)
The governor->governor callback is called with the current (or to-be-set)
cpufreq_policy struct for that CPU, and an unsigned int event. The
following events are currently defined:
CPUFREQ_GOV_START: This governor shall start its duty for the CPU
policy->cpu
CPUFREQ_GOV_STOP: This governor shall end its duty for the CPU
policy->cpu
CPUFREQ_GOV_LIMITS: The limits for CPU policy->cpu have changed to
policy->min and policy->max.
If you need other "events" externally of your driver, _only_ use the
cpufreq_governor_l(unsigned int cpu, unsigned int event) call to the
CPUfreq core to ensure proper locking.
governor->name - A unique name for this governor.
governor->owner - .THIS_MODULE for the governor module (if appropriate).
plus a set of hooks to the functions implementing the governor's logic.
The CPUfreq governor may call the CPU processor driver using one of
these two functions:
@ -258,12 +284,18 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int relation);
target_freq must be within policy->min and policy->max, of course.
What's the difference between these two functions? When your governor
still is in a direct code path of a call to governor->governor, the
per-CPU cpufreq lock is still held in the cpufreq core, and there's
no need to lock it again (in fact, this would cause a deadlock). So
use __cpufreq_driver_target only in these cases. In all other cases
(for example, when there's a "daemonized" function that wakes up
every second), use cpufreq_driver_target to lock the cpufreq per-CPU
lock before the command is passed to the cpufreq processor driver.
What's the difference between these two functions? When your governor is
in a direct code path of a call to governor callbacks, like
governor->start(), the policy->rwsem is still held in the cpufreq core,
and there's no need to lock it again (in fact, this would cause a
deadlock). So use __cpufreq_driver_target only in these cases. In all
other cases (for example, when there's a "daemonized" function that
wakes up every second), use cpufreq_driver_target to take policy->rwsem
before the command is passed to the cpufreq driver.
4. References
=============
[1] Per-entity load tracking: https://lwn.net/Articles/531853/
[2] Improvements in CPU frequency management: https://lwn.net/Articles/682391/

25
Documentation/cpu-freq/index.txt
View File

@ -18,16 +18,29 @@
Documents in this directory:
----------------------------
core.txt - General description of the CPUFreq core and
of CPUFreq notifiers
cpu-drivers.txt - How to implement a new cpufreq processor driver
amd-powernow.txt - AMD powernow driver specific file.
boost.txt - Frequency boosting support.
core.txt - General description of the CPUFreq core and
of CPUFreq notifiers.
cpu-drivers.txt - How to implement a new cpufreq processor driver.
cpufreq-nforce2.txt - nVidia nForce2 platform specific file.
cpufreq-stats.txt - General description of sysfs cpufreq stats.
governors.txt - What are cpufreq governors and how to
implement them?
index.txt - File index, Mailing list and Links (this document)
intel-pstate.txt - Intel pstate cpufreq driver specific file.
pcc-cpufreq.txt - PCC cpufreq driver specific file.
user-guide.txt - User Guide to CPUFreq
@ -35,9 +48,7 @@ Mailing List
------------
There is a CPU frequency changing CVS commit and general list where
you can report bugs, problems or submit patches. To post a message,
send an email to linux-pm@vger.kernel.org, to subscribe go to
http://vger.kernel.org/vger-lists.html#linux-pm and follow the
instructions there.
send an email to linux-pm@vger.kernel.org.
Links
-----
@ -48,7 +59,7 @@ how to access the CVS repository:
* http://cvs.arm.linux.org.uk/
the CPUFreq Mailing list:
* http://vger.kernel.org/vger-lists.html#cpufreq
* http://vger.kernel.org/vger-lists.html#linux-pm
Clock and voltage scaling for the SA-1100:
* http://www.lartmaker.nl/projects/scaling

15
Documentation/cpu-freq/intel-pstate.txt
View File

@ -85,6 +85,21 @@ Sysfs will show :
Refer to "Intel® 64 and IA-32 Architectures Software Developer’s Manual
Volume 3: System Programming Guide" to understand ratios.
There is one more sysfs attribute in /sys/devices/system/cpu/intel_pstate/
that can be used for controlling the operation mode of the driver:
status: Three settings are possible:
"off" - The driver is not in use at this time.
"active" - The driver works as a P-state governor (default).
"passive" - The driver works as a regular cpufreq one and collaborates
with the generic cpufreq governors (it sets P-states as
requested by those governors).
The current setting is returned by reads from this attribute. Writing one
of the above strings to it changes the operation mode as indicated by that
string, if possible. If HW-managed P-states (HWP) are enabled, it is not
possible to change the driver's operation mode and attempts to write to
this attribute will fail.
cpufreq sysfs for Intel P-State
Since this driver registers with cpufreq, cpufreq sysfs is also presented.

60
Documentation/cpu-freq/user-guide.txt
View File

@ -18,7 +18,7 @@
Contents:
---------
1. Supported Architectures and Processors
1.1 ARM
1.1 ARM and ARM64
1.2 x86
1.3 sparc64
1.4 ppc
@ -37,16 +37,10 @@ Contents:
1. Supported Architectures and Processors
=========================================
1.1 ARM
-------
The following ARM processors are supported by cpufreq:
ARM Integrator
ARM-SA1100
ARM-SA1110
Intel PXA
1.1 ARM and ARM64
-----------------
Almost all ARM and ARM64 platforms support CPU frequency scaling.
1.2 x86
-------
@ -69,6 +63,7 @@ Transmeta Crusoe
Transmeta Efficeon
VIA Cyrix 3 / C3
various processors on some ACPI 2.0-compatible systems [*]
And many more
[*] Only if "ACPI Processor Performance States" are available
to the ACPI<->BIOS interface.
@ -147,10 +142,19 @@ mounted it at /sys, the cpufreq interface is located in a subdirectory
"cpufreq" within the cpu-device directory
(e.g. /sys/devices/system/cpu/cpu0/cpufreq/ for the first CPU).
affected_cpus : List of Online CPUs that require software
coordination of frequency.
cpuinfo_cur_freq : Current frequency of the CPU as obtained from
the hardware, in KHz. This is the frequency
the CPU actually runs at.
cpuinfo_min_freq : this file shows the minimum operating
frequency the processor can run at(in kHz)
cpuinfo_max_freq : this file shows the maximum operating
frequency the processor can run at(in kHz)
cpuinfo_transition_latency The time it takes on this CPU to
switch between two frequencies in nano
seconds. If unknown or known to be
@ -163,25 +167,30 @@ cpuinfo_transition_latency The time it takes on this CPU to
userspace daemon. Make sure to not
switch the frequency too often
resulting in performance loss.
scaling_driver : this file shows what cpufreq driver is
used to set the frequency on this CPU
related_cpus : List of Online + Offline CPUs that need software
coordination of frequency.
scaling_available_frequencies : List of available frequencies, in KHz.
scaling_available_governors : this file shows the CPUfreq governors
available in this kernel. You can see the
currently activated governor in
scaling_cur_freq : Current frequency of the CPU as determined by
the governor and cpufreq core, in KHz. This is
the frequency the kernel thinks the CPU runs
at.
scaling_driver : this file shows what cpufreq driver is
used to set the frequency on this CPU
scaling_governor, and by "echoing" the name of another
governor you can change it. Please note
that some governors won't load - they only
work on some specific architectures or
processors.
cpuinfo_cur_freq : Current frequency of the CPU as obtained from
the hardware, in KHz. This is the frequency
the CPU actually runs at.
scaling_available_frequencies : List of available frequencies, in KHz.
scaling_min_freq and
scaling_max_freq show the current "policy limits" (in
kHz). By echoing new values into these
@ -190,16 +199,11 @@ scaling_max_freq show the current "policy limits" (in
first set scaling_max_freq, then
scaling_min_freq.
affected_cpus : List of Online CPUs that require software
coordination of frequency.
related_cpus : List of Online + Offline CPUs that need software
coordination of frequency.
scaling_cur_freq : Current frequency of the CPU as determined by
the governor and cpufreq core, in KHz. This is
the frequency the kernel thinks the CPU runs
at.
scaling_setspeed This can be read to get the currently programmed
value by the governor. This can be written to
change the current frequency for a group of
CPUs, represented by a policy. This is supported
currently only by the userspace governor.
bios_limit : If the BIOS tells the OS to limit a CPU to
lower frequencies, the user can read out the

128
Documentation/devicetree/bindings/cpufreq/ti-cpufreq.txt Normal file
View File

@ -0,0 +1,128 @@
TI CPUFreq and OPP bindings
================================
Certain TI SoCs, like those in the am335x, am437x, am57xx, and dra7xx
families support different OPPs depending on the silicon variant in use.
The ti-cpufreq driver can use revision and an efuse value from the SoC to
provide the OPP framework with supported hardware information. This is
used to determine which OPPs from the operating-points-v2 table get enabled
when it is parsed by the OPP framework.
Required properties:
--------------------
In 'cpus' nodes:
- operating-points-v2: Phandle to the operating-points-v2 table to use.
In 'operating-points-v2' table:
- compatible: Should be
- 'operating-points-v2-ti-cpu' for am335x, am43xx, and dra7xx/am57xx SoCs
- syscon: A phandle pointing to a syscon node representing the control module
register space of the SoC.
Optional properties:
--------------------
For each opp entry in 'operating-points-v2' table:
- opp-supported-hw: Two bitfields indicating:
1. Which revision of the SoC the OPP is supported by
2. Which eFuse bits indicate this OPP is available
A bitwise AND is performed against these values and if any bit
matches, the OPP gets enabled.
Example:
--------
/* From arch/arm/boot/dts/am33xx.dtsi */
cpus {
#address-cells = <1>;
#size-cells = <0>;
cpu@0 {
compatible = "arm,cortex-a8";
device_type = "cpu";
reg = <0>;
operating-points-v2 = <&cpu0_opp_table>;
clocks = <&dpll_mpu_ck>;
clock-names = "cpu";
clock-latency = <300000>; /* From omap-cpufreq driver */
};
};
/*
* cpu0 has different OPPs depending on SoC revision and some on revisions
* 0x2 and 0x4 have eFuse bits that indicate if they are available or not
*/
cpu0_opp_table: opp-table {
compatible = "operating-points-v2-ti-cpu";
syscon = <&scm_conf>;
/*
* The three following nodes are marked with opp-suspend
* because they can not be enabled simultaneously on a
* single SoC.
*/
opp50@300000000 {
opp-hz = /bits/ 64 <300000000>;
opp-microvolt = <950000 931000 969000>;
opp-supported-hw = <0x06 0x0010>;
opp-suspend;
};
opp100@275000000 {
opp-hz = /bits/ 64 <275000000>;
opp-microvolt = <1100000 1078000 1122000>;
opp-supported-hw = <0x01 0x00FF>;
opp-suspend;
};
opp100@300000000 {
opp-hz = /bits/ 64 <300000000>;
opp-microvolt = <1100000 1078000 1122000>;
opp-supported-hw = <0x06 0x0020>;
opp-suspend;
};
opp100@500000000 {
opp-hz = /bits/ 64 <500000000>;
opp-microvolt = <1100000 1078000 1122000>;
opp-supported-hw = <0x01 0xFFFF>;
};
opp100@600000000 {
opp-hz = /bits/ 64 <600000000>;
opp-microvolt = <1100000 1078000 1122000>;
opp-supported-hw = <0x06 0x0040>;
};
opp120@600000000 {
opp-hz = /bits/ 64 <600000000>;
opp-microvolt = <1200000 1176000 1224000>;
opp-supported-hw = <0x01 0xFFFF>;
};
opp120@720000000 {
opp-hz = /bits/ 64 <720000000>;
opp-microvolt = <1200000 1176000 1224000>;
opp-supported-hw = <0x06 0x0080>;
};
oppturbo@720000000 {
opp-hz = /bits/ 64 <720000000>;
opp-microvolt = <1260000 1234800 1285200>;
opp-supported-hw = <0x01 0xFFFF>;
};
oppturbo@800000000 {
opp-hz = /bits/ 64 <800000000>;
opp-microvolt = <1260000 1234800 1285200>;
opp-supported-hw = <0x06 0x0100>;
};
oppnitro@1000000000 {
opp-hz = /bits/ 64 <1000000000>;
opp-microvolt = <1325000 1298500 1351500>;
opp-supported-hw = <0x04 0x0200>;
};
};

7
MAINTAINERS
View File

@ -2692,6 +2692,13 @@ F: drivers/irqchip/irq-brcmstb*
F: include/linux/bcm963xx_nvram.h
F: include/linux/bcm963xx_tag.h
BROADCOM BMIPS CPUFREQ DRIVER
M: Markus Mayer <mmayer@broadcom.com>
M: bcm-kernel-feedback-list@broadcom.com
L: linux-pm@vger.kernel.org
S: Maintained
F: drivers/cpufreq/bmips-cpufreq.c
BROADCOM TG3 GIGABIT ETHERNET DRIVER
M: Siva Reddy Kallam <siva.kallam@broadcom.com>
M: Prashant Sreedharan <prashant@broadcom.com>

2
arch/arm/configs/exynos_defconfig
View File

@ -24,7 +24,7 @@ CONFIG_ARM_APPENDED_DTB=y
CONFIG_ARM_ATAG_DTB_COMPAT=y
CONFIG_CMDLINE="root=/dev/ram0 rw ramdisk=8192 initrd=0x41000000,8M console=ttySAC1,115200 init=/linuxrc mem=256M"
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m

2
arch/arm/configs/multi_v5_defconfig
View File

@ -58,7 +58,7 @@ CONFIG_ZBOOT_ROM_BSS=0x0
CONFIG_ARM_APPENDED_DTB=y
CONFIG_ARM_ATAG_DTB_COMPAT=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_CPU_IDLE=y
CONFIG_ARM_KIRKWOOD_CPUIDLE=y

2
arch/arm/configs/multi_v7_defconfig
View File

@ -132,7 +132,7 @@ CONFIG_ARM_ATAG_DTB_COMPAT=y
CONFIG_KEXEC=y
CONFIG_EFI=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m

2
arch/arm/configs/mvebu_v5_defconfig
View File

@ -44,7 +44,7 @@ CONFIG_ZBOOT_ROM_BSS=0x0
CONFIG_ARM_APPENDED_DTB=y
CONFIG_ARM_ATAG_DTB_COMPAT=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_CPU_IDLE=y
CONFIG_ARM_KIRKWOOD_CPUIDLE=y

2
arch/arm/configs/pxa_defconfig
View File

@ -97,7 +97,7 @@ CONFIG_ZBOOT_ROM_BSS=0x0
CONFIG_CMDLINE="root=/dev/ram0 ro"
CONFIG_KEXEC=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m

2
arch/arm/configs/shmobile_defconfig
View File

@ -38,7 +38,7 @@ CONFIG_ZBOOT_ROM_BSS=0x0
CONFIG_ARM_APPENDED_DTB=y
CONFIG_KEXEC=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=y
CONFIG_CPU_FREQ_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y

2
arch/mips/Kconfig
View File

@ -1703,6 +1703,8 @@ config CPU_BMIPS
select WEAK_ORDERING
select CPU_SUPPORTS_HIGHMEM
select CPU_HAS_PREFETCH
select CPU_SUPPORTS_CPUFREQ
select MIPS_EXTERNAL_TIMER
help
Support for BMIPS32/3300/4350/4380 and BMIPS5000 processors.

16
arch/mips/configs/bmips_stb_defconfig
View File

@ -9,13 +9,20 @@ CONFIG_MIPS_O32_FP64_SUPPORT=y
# CONFIG_SWAP is not set
CONFIG_NO_HZ=y
CONFIG_BLK_DEV_INITRD=y
CONFIG_RD_GZIP=y
CONFIG_EXPERT=y
# CONFIG_VM_EVENT_COUNTERS is not set
# CONFIG_SLUB_DEBUG is not set
# CONFIG_BLK_DEV_BSG is not set
# CONFIG_IOSCHED_DEADLINE is not set
# CONFIG_IOSCHED_CFQ is not set
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=y
CONFIG_CPU_FREQ_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y
CONFIG_CPU_FREQ_GOV_SCHEDUTIL=y
CONFIG_BMIPS_CPUFREQ=y
CONFIG_NET=y
CONFIG_PACKET=y
CONFIG_PACKET_DIAG=y
@ -24,7 +31,6 @@ CONFIG_INET=y
# CONFIG_INET_XFRM_MODE_TRANSPORT is not set
# CONFIG_INET_XFRM_MODE_TUNNEL is not set
# CONFIG_INET_XFRM_MODE_BEET is not set
# CONFIG_INET_LRO is not set
# CONFIG_INET_DIAG is not set
CONFIG_CFG80211=y
CONFIG_NL80211_TESTMODE=y
@ -34,8 +40,6 @@ CONFIG_DEVTMPFS=y
CONFIG_DEVTMPFS_MOUNT=y
# CONFIG_STANDALONE is not set
# CONFIG_PREVENT_FIRMWARE_BUILD is not set
CONFIG_PRINTK_TIME=y
CONFIG_BRCMSTB_GISB_ARB=y
CONFIG_MTD=y
CONFIG_MTD_CFI=y
CONFIG_MTD_CFI_INTELEXT=y
@ -51,16 +55,15 @@ CONFIG_USB_USBNET=y
# CONFIG_INPUT is not set
# CONFIG_SERIO is not set
# CONFIG_VT is not set
# CONFIG_DEVKMEM is not set
CONFIG_SERIAL_8250=y
# CONFIG_SERIAL_8250_DEPRECATED_OPTIONS is not set
CONFIG_SERIAL_8250_CONSOLE=y
CONFIG_SERIAL_OF_PLATFORM=y
# CONFIG_HW_RANDOM is not set
CONFIG_POWER_SUPPLY=y
CONFIG_POWER_RESET=y
CONFIG_POWER_RESET_BRCMSTB=y
CONFIG_POWER_RESET_SYSCON=y
CONFIG_POWER_SUPPLY=y
# CONFIG_HWMON is not set
CONFIG_USB=y
CONFIG_USB_EHCI_HCD=y
@ -82,6 +85,7 @@ CONFIG_CIFS=y
CONFIG_NLS_CODEPAGE_437=y
CONFIG_NLS_ASCII=y
CONFIG_NLS_ISO8859_1=y
CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_FS=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_CMDLINE_BOOL=y

1
arch/mips/configs/lemote2f_defconfig
View File

@ -40,7 +40,6 @@ CONFIG_PM_STD_PARTITION="/dev/hda3"
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_DEBUG=y
CONFIG_CPU_FREQ_STAT=m
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m

1
arch/powerpc/configs/ppc6xx_defconfig
View File

@ -62,7 +62,6 @@ CONFIG_MPC8610_HPCD=y
CONFIG_GEF_SBC610=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT=m
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m

2
arch/sh/configs/sh7785lcr_32bit_defconfig
View File

@ -25,7 +25,7 @@ CONFIG_SH_SH7785LCR=y
CONFIG_NO_HZ=y
CONFIG_HIGH_RES_TIMERS=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
CONFIG_SH_CPU_FREQ=y
CONFIG_HEARTBEAT=y

4
drivers/acpi/processor_perflib.c
View File

@ -75,10 +75,8 @@ static int acpi_processor_ppc_notifier(struct notifier_block *nb,
struct acpi_processor *pr;
unsigned int ppc = 0;
if (event == CPUFREQ_START && ignore_ppc <= 0) {
if (ignore_ppc < 0)
ignore_ppc = 0;
return 0;
}
if (ignore_ppc)
return 0;

20
drivers/cpufreq/Kconfig
View File

@ -37,14 +37,6 @@ config CPU_FREQ_STAT
If in doubt, say N.
config CPU_FREQ_STAT_DETAILS
bool "CPU frequency transition statistics details"
depends on CPU_FREQ_STAT
help
Show detailed CPU frequency transition table in sysfs.
If in doubt, say N.
choice
prompt "Default CPUFreq governor"
default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
@ -271,6 +263,16 @@ config IA64_ACPI_CPUFREQ
endif
if MIPS
config BMIPS_CPUFREQ
tristate "BMIPS CPUfreq Driver"
help
This option adds a CPUfreq driver for BMIPS processors with
support for configurable CPU frequency.
For now, BMIPS5 chips are supported (such as the Broadcom 7425).
If in doubt, say N.
config LOONGSON2_CPUFREQ
tristate "Loongson2 CPUFreq Driver"
help
@ -332,7 +334,7 @@ endif
config QORIQ_CPUFREQ
tristate "CPU frequency scaling driver for Freescale QorIQ SoCs"
depends on OF && COMMON_CLK && (PPC_E500MC || ARM)
depends on OF && COMMON_CLK && (PPC_E500MC || ARM || ARM64)
depends on !CPU_THERMAL || THERMAL
select CLK_QORIQ
help

13
drivers/cpufreq/Kconfig.arm
View File

@ -247,6 +247,17 @@ config ARM_TEGRA124_CPUFREQ
help
This adds the CPUFreq driver support for Tegra124 SOCs.
config ARM_TI_CPUFREQ
bool "Texas Instruments CPUFreq support"
depends on ARCH_OMAP2PLUS
help
This driver enables valid OPPs on the running platform based on
values contained within the SoC in use. Enable this in order to
use the cpufreq-dt driver on all Texas Instruments platforms that
provide dt based operating-points-v2 tables with opp-supported-hw
data provided. Required for cpufreq support on AM335x, AM437x,
DRA7x, and AM57x platforms.
config ARM_PXA2xx_CPUFREQ
tristate "Intel PXA2xx CPUfreq driver"
depends on PXA27x || PXA25x
@ -257,7 +268,7 @@ config ARM_PXA2xx_CPUFREQ
config ACPI_CPPC_CPUFREQ
tristate "CPUFreq driver based on the ACPI CPPC spec"
depends on ACPI
depends on ACPI_PROCESSOR
select ACPI_CPPC_LIB
default n
help

2
drivers/cpufreq/Makefile
View File

@ -77,6 +77,7 @@ obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o
obj-$(CONFIG_ARM_STI_CPUFREQ) += sti-cpufreq.o
obj-$(CONFIG_ARM_TEGRA20_CPUFREQ) += tegra20-cpufreq.o
obj-$(CONFIG_ARM_TEGRA124_CPUFREQ) += tegra124-cpufreq.o
obj-$(CONFIG_ARM_TI_CPUFREQ) += ti-cpufreq.o
obj-$(CONFIG_ARM_VEXPRESS_SPC_CPUFREQ) += vexpress-spc-cpufreq.o
obj-$(CONFIG_ACPI_CPPC_CPUFREQ) += cppc_cpufreq.o
obj-$(CONFIG_MACH_MVEBU_V7) += mvebu-cpufreq.o
@ -98,6 +99,7 @@ obj-$(CONFIG_POWERNV_CPUFREQ) += powernv-cpufreq.o
# Other platform drivers
obj-$(CONFIG_AVR32_AT32AP_CPUFREQ) += at32ap-cpufreq.o
obj-$(CONFIG_BFIN_CPU_FREQ) += blackfin-cpufreq.o
obj-$(CONFIG_BMIPS_CPUFREQ) += bmips-cpufreq.o
obj-$(CONFIG_CRIS_MACH_ARTPEC3) += cris-artpec3-cpufreq.o
obj-$(CONFIG_ETRAXFS) += cris-etraxfs-cpufreq.o
obj-$(CONFIG_IA64_ACPI_CPUFREQ) += ia64-acpi-cpufreq.o

188
drivers/cpufreq/bmips-cpufreq.c Normal file
View File

@ -0,0 +1,188 @@
/*
* CPU frequency scaling for Broadcom BMIPS SoCs
*
* Copyright (c) 2017 Broadcom
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/cpufreq.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/slab.h>
/* for mips_hpt_frequency */
#include <asm/time.h>
#define BMIPS_CPUFREQ_PREFIX "bmips"
#define BMIPS_CPUFREQ_NAME BMIPS_CPUFREQ_PREFIX "-cpufreq"
#define TRANSITION_LATENCY (25 * 1000) /* 25 us */
#define BMIPS5_CLK_DIV_SET_SHIFT 0x7
#define BMIPS5_CLK_DIV_SHIFT 0x4
#define BMIPS5_CLK_DIV_MASK 0xf
enum bmips_type {
BMIPS5000,
BMIPS5200,
};
struct cpufreq_compat {
const char *compatible;
unsigned int bmips_type;
unsigned int clk_mult;
unsigned int max_freqs;
};
#define BMIPS(c, t, m, f) { \
.compatible = c, \
.bmips_type = (t), \
.clk_mult = (m), \
.max_freqs = (f), \
}
static struct cpufreq_compat bmips_cpufreq_compat[] = {
BMIPS("brcm,bmips5000", BMIPS5000, 8, 4),
BMIPS("brcm,bmips5200", BMIPS5200, 8, 4),
{ }
};
static struct cpufreq_compat *priv;
static int htp_freq_to_cpu_freq(unsigned int clk_mult)
{
return mips_hpt_frequency * clk_mult / 1000;
}
static struct cpufreq_frequency_table *
bmips_cpufreq_get_freq_table(const struct cpufreq_policy *policy)
{
struct cpufreq_frequency_table *table;
unsigned long cpu_freq;
int i;
cpu_freq = htp_freq_to_cpu_freq(priv->clk_mult);
table = kmalloc((priv->max_freqs + 1) * sizeof(*table), GFP_KERNEL);
if (!table)
return ERR_PTR(-ENOMEM);
for (i = 0; i < priv->max_freqs; i++) {
table[i].frequency = cpu_freq / (1 << i);
table[i].driver_data = i;
}
table[i].frequency = CPUFREQ_TABLE_END;
return table;
}
static unsigned int bmips_cpufreq_get(unsigned int cpu)
{
unsigned int div;
uint32_t mode;
switch (priv->bmips_type) {
case BMIPS5200:
case BMIPS5000:
mode = read_c0_brcm_mode();
div = ((mode >> BMIPS5_CLK_DIV_SHIFT) & BMIPS5_CLK_DIV_MASK);
break;
default:
div = 0;
}
return htp_freq_to_cpu_freq(priv->clk_mult) / (1 << div);
}
static int bmips_cpufreq_target_index(struct cpufreq_policy *policy,
unsigned int index)
{
unsigned int div = policy->freq_table[index].driver_data;
switch (priv->bmips_type) {
case BMIPS5200:
case BMIPS5000:
change_c0_brcm_mode(BMIPS5_CLK_DIV_MASK << BMIPS5_CLK_DIV_SHIFT,
(1 << BMIPS5_CLK_DIV_SET_SHIFT) |
(div << BMIPS5_CLK_DIV_SHIFT));
break;
default:
return -ENOTSUPP;
}
return 0;
}
static int bmips_cpufreq_exit(struct cpufreq_policy *policy)
{
kfree(policy->freq_table);
return 0;
}
static int bmips_cpufreq_init(struct cpufreq_policy *policy)
{
struct cpufreq_frequency_table *freq_table;
int ret;
freq_table = bmips_cpufreq_get_freq_table(policy);
if (IS_ERR(freq_table)) {
ret = PTR_ERR(freq_table);
pr_err("%s: couldn't determine frequency table (%d).\n",
BMIPS_CPUFREQ_NAME, ret);
return ret;
}
ret = cpufreq_generic_init(policy, freq_table, TRANSITION_LATENCY);
if (ret)
bmips_cpufreq_exit(policy);
else
pr_info("%s: registered\n", BMIPS_CPUFREQ_NAME);
return ret;
}
static struct cpufreq_driver bmips_cpufreq_driver = {
.flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.verify = cpufreq_generic_frequency_table_verify,
.target_index = bmips_cpufreq_target_index,
.get = bmips_cpufreq_get,
.init = bmips_cpufreq_init,
.exit = bmips_cpufreq_exit,
.attr = cpufreq_generic_attr,
.name = BMIPS_CPUFREQ_PREFIX,
};
static int __init bmips_cpufreq_probe(void)
{
struct cpufreq_compat *cc;
struct device_node *np;
for (cc = bmips_cpufreq_compat; cc->compatible; cc++) {
np = of_find_compatible_node(NULL, "cpu", cc->compatible);
if (np) {
of_node_put(np);
priv = cc;
break;
}
}
/* We hit the guard element of the array. No compatible CPU found. */
if (!cc->compatible)
return -ENODEV;
return cpufreq_register_driver(&bmips_cpufreq_driver);
}
device_initcall(bmips_cpufreq_probe);
MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
MODULE_DESCRIPTION("CPUfreq driver for Broadcom BMIPS SoCs");
MODULE_LICENSE("GPL");

2
drivers/cpufreq/brcmstb-avs-cpufreq.c
View File

@ -878,7 +878,6 @@ unmap_intr_base:
iounmap(priv->avs_intr_base);
unmap_base:
iounmap(priv->base);
platform_set_drvdata(pdev, NULL);
return ret;
}
@ -1042,7 +1041,6 @@ static int brcm_avs_cpufreq_remove(struct platform_device *pdev)
priv = platform_get_drvdata(pdev);
iounmap(priv->base);
iounmap(priv->avs_intr_base);
platform_set_drvdata(pdev, NULL);
return 0;
}

2
drivers/cpufreq/cpufreq-dt-platdev.c
View File

@ -87,8 +87,6 @@ static const struct of_device_id machines[] __initconst = {
{ .compatible = "socionext,uniphier-ld11", },
{ .compatible = "socionext,uniphier-ld20", },
{ .compatible = "ti,am33xx", },
{ .compatible = "ti,dra7", },
{ .compatible = "ti,omap2", },
{ .compatible = "ti,omap3", },
{ .compatible = "ti,omap4", },

21
drivers/cpufreq/cpufreq.c
View File

@ -1078,15 +1078,11 @@ err_free_policy:
return NULL;
}
static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify)
static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy)
{
struct kobject *kobj;
struct completion *cmp;
if (notify)
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
CPUFREQ_REMOVE_POLICY, policy);
down_write(&policy->rwsem);
cpufreq_stats_free_table(policy);
kobj = &policy->kobj;
@ -1104,7 +1100,7 @@ static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify)
pr_debug("wait complete\n");
}
static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify)
static void cpufreq_policy_free(struct cpufreq_policy *policy)
{
unsigned long flags;
int cpu;
@ -1117,7 +1113,7 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify)
per_cpu(cpufreq_cpu_data, cpu) = NULL;
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
cpufreq_policy_put_kobj(policy, notify);
cpufreq_policy_put_kobj(policy);
free_cpumask_var(policy->real_cpus);
free_cpumask_var(policy->related_cpus);
free_cpumask_var(policy->cpus);
@ -1170,8 +1166,6 @@ static int cpufreq_online(unsigned int cpu)
if (new_policy) {
/* related_cpus should at least include policy->cpus. */
cpumask_copy(policy->related_cpus, policy->cpus);
/* Clear mask of registered CPUs */
cpumask_clear(policy->real_cpus);
}
/*
@ -1244,17 +1238,12 @@ static int cpufreq_online(unsigned int cpu)
goto out_exit_policy;
cpufreq_stats_create_table(policy);
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
CPUFREQ_CREATE_POLICY, policy);
write_lock_irqsave(&cpufreq_driver_lock, flags);
list_add(&policy->policy_list, &cpufreq_policy_list);
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
}
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
CPUFREQ_START, policy);
ret = cpufreq_init_policy(policy);
if (ret) {
pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n",
@ -1282,7 +1271,7 @@ out_exit_policy:
if (cpufreq_driver->exit)
cpufreq_driver->exit(policy);
out_free_policy:
cpufreq_policy_free(policy, !new_policy);
cpufreq_policy_free(policy);
return ret;
}
@ -1403,7 +1392,7 @@ static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
remove_cpu_dev_symlink(policy, dev);
if (cpumask_empty(policy->real_cpus))
cpufreq_policy_free(policy, true);
cpufreq_policy_free(policy);
}
/**

14
drivers/cpufreq/cpufreq_stats.c
View File

@ -25,9 +25,7 @@ struct cpufreq_stats {
unsigned int last_index;
u64 *time_in_state;
unsigned int *freq_table;
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
unsigned int *trans_table;
#endif
};
static int cpufreq_stats_update(struct cpufreq_stats *stats)
@ -46,9 +44,7 @@ static void cpufreq_stats_clear_table(struct cpufreq_stats *stats)
unsigned int count = stats->max_state;
memset(stats->time_in_state, 0, count * sizeof(u64));
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
memset(stats->trans_table, 0, count * count * sizeof(int));
#endif
stats->last_time = get_jiffies_64();
stats->total_trans = 0;
}
@ -84,7 +80,6 @@ static ssize_t store_reset(struct cpufreq_policy *policy, const char *buf,
return count;
}
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
{
struct cpufreq_stats *stats = policy->stats;
@ -129,7 +124,6 @@ static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
return len;
}
cpufreq_freq_attr_ro(trans_table);
#endif
cpufreq_freq_attr_ro(total_trans);
cpufreq_freq_attr_ro(time_in_state);
@ -139,9 +133,7 @@ static struct attribute *default_attrs[] = {
&total_trans.attr,
&time_in_state.attr,
&reset.attr,
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
&trans_table.attr,
#endif
NULL
};
static struct attribute_group stats_attr_group = {
@ -200,9 +192,7 @@ void cpufreq_stats_create_table(struct cpufreq_policy *policy)
alloc_size = count * sizeof(int) + count * sizeof(u64);
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
alloc_size += count * count * sizeof(int);
#endif
/* Allocate memory for time_in_state/freq_table/trans_table in one go */
stats->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
@ -211,9 +201,7 @@ void cpufreq_stats_create_table(struct cpufreq_policy *policy)
stats->freq_table = (unsigned int *)(stats->time_in_state + count);
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
stats->trans_table = stats->freq_table + count;
#endif
stats->max_state = count;
@ -259,8 +247,6 @@ void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
cpufreq_stats_update(stats);
stats->last_index = new_index;
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
stats->trans_table[old_index * stats->max_state + new_index]++;
#endif
stats->total_trans++;
}

385
drivers/cpufreq/intel_pstate.c
View File

@ -358,6 +358,8 @@ static struct pstate_funcs pstate_funcs __read_mostly;
static int hwp_active __read_mostly;
static bool per_cpu_limits __read_mostly;
static bool driver_registered __read_mostly;
#ifdef CONFIG_ACPI
static bool acpi_ppc;
#endif
@ -394,6 +396,7 @@ static struct perf_limits *limits = &performance_limits;
static struct perf_limits *limits = &powersave_limits;
#endif
static DEFINE_MUTEX(intel_pstate_driver_lock);
static DEFINE_MUTEX(intel_pstate_limits_lock);
#ifdef CONFIG_ACPI
@ -538,7 +541,6 @@ static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
acpi_processor_unregister_performance(policy->cpu);
}
#else
static inline void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
{
@ -873,7 +875,10 @@ static void intel_pstate_hwp_set(struct cpufreq_policy *policy)
rdmsrl_on_cpu(cpu, MSR_HWP_CAPABILITIES, &cap);
hw_min = HWP_LOWEST_PERF(cap);
hw_max = HWP_HIGHEST_PERF(cap);
if (limits->no_turbo)
hw_max = HWP_GUARANTEED_PERF(cap);
else
hw_max = HWP_HIGHEST_PERF(cap);
range = hw_max - hw_min;
max_perf_pct = perf_limits->max_perf_pct;
@ -887,11 +892,6 @@ static void intel_pstate_hwp_set(struct cpufreq_policy *policy)
adj_range = max_perf_pct * range / 100;
max = hw_min + adj_range;
if (limits->no_turbo) {
hw_max = HWP_GUARANTEED_PERF(cap);
if (hw_max < max)
max = hw_max;
}
value &= ~HWP_MAX_PERF(~0L);
value |= HWP_MAX_PERF(max);
@ -1007,37 +1007,59 @@ static int pid_param_get(void *data, u64 *val)
}
DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
static struct dentry *debugfs_parent;
struct pid_param {
char *name;
void *value;
struct dentry *dentry;
};
static struct pid_param pid_files[] = {
{"sample_rate_ms", &pid_params.sample_rate_ms},
{"d_gain_pct", &pid_params.d_gain_pct},
{"i_gain_pct", &pid_params.i_gain_pct},
{"deadband", &pid_params.deadband},
{"setpoint", &pid_params.setpoint},
{"p_gain_pct", &pid_params.p_gain_pct},
{NULL, NULL}
{"sample_rate_ms", &pid_params.sample_rate_ms, },
{"d_gain_pct", &pid_params.d_gain_pct, },
{"i_gain_pct", &pid_params.i_gain_pct, },
{"deadband", &pid_params.deadband, },
{"setpoint", &pid_params.setpoint, },
{"p_gain_pct", &pid_params.p_gain_pct, },
{NULL, NULL, }
};
static void __init intel_pstate_debug_expose_params(void)
static void intel_pstate_debug_expose_params(void)
{
struct dentry *debugfs_parent;
int i = 0;
int i;
debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
if (IS_ERR_OR_NULL(debugfs_parent))
return;
while (pid_files[i].name) {
debugfs_create_file(pid_files[i].name, 0660,
debugfs_parent, pid_files[i].value,
&fops_pid_param);
i++;
for (i = 0; pid_files[i].name; i++) {
struct dentry *dentry;
dentry = debugfs_create_file(pid_files[i].name, 0660,
debugfs_parent, pid_files[i].value,
&fops_pid_param);
if (!IS_ERR(dentry))
pid_files[i].dentry = dentry;
}
}
static void intel_pstate_debug_hide_params(void)
{
int i;
if (IS_ERR_OR_NULL(debugfs_parent))
return;
for (i = 0; pid_files[i].name; i++) {
debugfs_remove(pid_files[i].dentry);
pid_files[i].dentry = NULL;
}
debugfs_remove(debugfs_parent);
debugfs_parent = NULL;
}
/************************** debugfs end ************************/
/************************** sysfs begin ************************/
@ -1048,6 +1070,34 @@ static void __init intel_pstate_debug_expose_params(void)
return sprintf(buf, "%u\n", limits->object); \
}
static ssize_t intel_pstate_show_status(char *buf);
static int intel_pstate_update_status(const char *buf, size_t size);
static ssize_t show_status(struct kobject *kobj,
struct attribute *attr, char *buf)
{
ssize_t ret;
mutex_lock(&intel_pstate_driver_lock);
ret = intel_pstate_show_status(buf);
mutex_unlock(&intel_pstate_driver_lock);
return ret;
}
static ssize_t store_status(struct kobject *a, struct attribute *b,
const char *buf, size_t count)
{
char *p = memchr(buf, '\n', count);
int ret;
mutex_lock(&intel_pstate_driver_lock);
ret = intel_pstate_update_status(buf, p ? p - buf : count);
mutex_unlock(&intel_pstate_driver_lock);
return ret < 0 ? ret : count;
}
static ssize_t show_turbo_pct(struct kobject *kobj,
struct attribute *attr, char *buf)
{
@ -1055,12 +1105,22 @@ static ssize_t show_turbo_pct(struct kobject *kobj,
int total, no_turbo, turbo_pct;
uint32_t turbo_fp;
mutex_lock(&intel_pstate_driver_lock);
if (!driver_registered) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
cpu = all_cpu_data[0];
total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
turbo_fp = div_fp(no_turbo, total);
turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
mutex_unlock(&intel_pstate_driver_lock);
return sprintf(buf, "%u\n", turbo_pct);
}
@ -1070,8 +1130,18 @@ static ssize_t show_num_pstates(struct kobject *kobj,
struct cpudata *cpu;
int total;
mutex_lock(&intel_pstate_driver_lock);
if (!driver_registered) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
cpu = all_cpu_data[0];
total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
mutex_unlock(&intel_pstate_driver_lock);
return sprintf(buf, "%u\n", total);
}
@ -1080,12 +1150,21 @@ static ssize_t show_no_turbo(struct kobject *kobj,
{
ssize_t ret;
mutex_lock(&intel_pstate_driver_lock);
if (!driver_registered) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
update_turbo_state();
if (limits->turbo_disabled)
ret = sprintf(buf, "%u\n", limits->turbo_disabled);
else
ret = sprintf(buf, "%u\n", limits->no_turbo);
mutex_unlock(&intel_pstate_driver_lock);
return ret;
}
@ -1099,12 +1178,20 @@ static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
if (ret != 1)
return -EINVAL;
mutex_lock(&intel_pstate_driver_lock);
if (!driver_registered) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
mutex_lock(&intel_pstate_limits_lock);
update_turbo_state();
if (limits->turbo_disabled) {
pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
mutex_unlock(&intel_pstate_limits_lock);
mutex_unlock(&intel_pstate_driver_lock);
return -EPERM;
}
@ -1114,6 +1201,8 @@ static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
intel_pstate_update_policies();
mutex_unlock(&intel_pstate_driver_lock);
return count;
}
@ -1127,6 +1216,13 @@ static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
if (ret != 1)
return -EINVAL;
mutex_lock(&intel_pstate_driver_lock);
if (!driver_registered) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
mutex_lock(&intel_pstate_limits_lock);
limits->max_sysfs_pct = clamp_t(int, input, 0 , 100);
@ -1142,6 +1238,8 @@ static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
intel_pstate_update_policies();
mutex_unlock(&intel_pstate_driver_lock);
return count;
}
@ -1155,6 +1253,13 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
if (ret != 1)
return -EINVAL;
mutex_lock(&intel_pstate_driver_lock);
if (!driver_registered) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
mutex_lock(&intel_pstate_limits_lock);
limits->min_sysfs_pct = clamp_t(int, input, 0 , 100);
@ -1170,12 +1275,15 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
intel_pstate_update_policies();
mutex_unlock(&intel_pstate_driver_lock);
return count;
}
show_one(max_perf_pct, max_perf_pct);
show_one(min_perf_pct, min_perf_pct);
define_one_global_rw(status);
define_one_global_rw(no_turbo);
define_one_global_rw(max_perf_pct);
define_one_global_rw(min_perf_pct);
@ -1183,6 +1291,7 @@ define_one_global_ro(turbo_pct);
define_one_global_ro(num_pstates);
static struct attribute *intel_pstate_attributes[] = {
&status.attr,
&no_turbo.attr,
&turbo_pct.attr,
&num_pstates.attr,
@ -1364,48 +1473,71 @@ static int core_get_max_pstate_physical(void)
return (value >> 8) & 0xFF;
}
static int core_get_tdp_ratio(u64 plat_info)
{
/* Check how many TDP levels present */
if (plat_info & 0x600000000) {
u64 tdp_ctrl;
u64 tdp_ratio;
int tdp_msr;
int err;
/* Get the TDP level (0, 1, 2) to get ratios */
err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
if (err)
return err;
/* TDP MSR are continuous starting at 0x648 */
tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x03);
err = rdmsrl_safe(tdp_msr, &tdp_ratio);
if (err)
return err;
/* For level 1 and 2, bits[23:16] contain the ratio */
if (tdp_ctrl & 0x03)
tdp_ratio >>= 16;
tdp_ratio &= 0xff; /* ratios are only 8 bits long */
pr_debug("tdp_ratio %x\n", (int)tdp_ratio);
return (int)tdp_ratio;
}
return -ENXIO;
}
static int core_get_max_pstate(void)
{
u64 tar;
u64 plat_info;
int max_pstate;
int tdp_ratio;
int err;
rdmsrl(MSR_PLATFORM_INFO, plat_info);
max_pstate = (plat_info >> 8) & 0xFF;
tdp_ratio = core_get_tdp_ratio(plat_info);
if (tdp_ratio <= 0)
return max_pstate;
if (hwp_active) {
/* Turbo activation ratio is not used on HWP platforms */
return tdp_ratio;
}
err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
if (!err) {
int tar_levels;
/* Do some sanity checking for safety */
if (plat_info & 0x600000000) {
u64 tdp_ctrl;
u64 tdp_ratio;
int tdp_msr;
err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
if (err)
goto skip_tar;
tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x3);
err = rdmsrl_safe(tdp_msr, &tdp_ratio);
if (err)
goto skip_tar;
/* For level 1 and 2, bits[23:16] contain the ratio */
if (tdp_ctrl)
tdp_ratio >>= 16;
tdp_ratio &= 0xff; /* ratios are only 8 bits long */
if (tdp_ratio - 1 == tar) {
max_pstate = tar;
pr_debug("max_pstate=TAC %x\n", max_pstate);
} else {
goto skip_tar;
}
tar_levels = tar & 0xff;
if (tdp_ratio - 1 == tar_levels) {
max_pstate = tar_levels;
pr_debug("max_pstate=TAC %x\n", max_pstate);
}
}
skip_tar:
return max_pstate;
}
@ -2072,6 +2204,20 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
{
struct cpudata *cpu = all_cpu_data[policy->cpu];
struct perf_limits *perf_limits;
if (policy->policy == CPUFREQ_POLICY_PERFORMANCE)
perf_limits = &performance_limits;
else
perf_limits = &powersave_limits;
update_turbo_state();
policy->cpuinfo.max_freq = perf_limits->turbo_disabled ||
perf_limits->no_turbo ?
cpu->pstate.max_freq :
cpu->pstate.turbo_freq;
cpufreq_verify_within_cpu_limits(policy);
if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
@ -2299,6 +2445,111 @@ static struct cpufreq_driver intel_cpufreq = {
static struct cpufreq_driver *intel_pstate_driver = &intel_pstate;
static void intel_pstate_driver_cleanup(void)
{
unsigned int cpu;
get_online_cpus();
for_each_online_cpu(cpu) {
if (all_cpu_data[cpu]) {
if (intel_pstate_driver == &intel_pstate)
intel_pstate_clear_update_util_hook(cpu);
kfree(all_cpu_data[cpu]);
all_cpu_data[cpu] = NULL;
}
}
put_online_cpus();
}
static int intel_pstate_register_driver(void)
{
int ret;
ret = cpufreq_register_driver(intel_pstate_driver);
if (ret) {
intel_pstate_driver_cleanup();
return ret;
}
mutex_lock(&intel_pstate_limits_lock);
driver_registered = true;
mutex_unlock(&intel_pstate_limits_lock);
if (intel_pstate_driver == &intel_pstate && !hwp_active &&
pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
intel_pstate_debug_expose_params();
return 0;
}
static int intel_pstate_unregister_driver(void)
{
if (hwp_active)
return -EBUSY;
if (intel_pstate_driver == &intel_pstate && !hwp_active &&
pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
intel_pstate_debug_hide_params();
mutex_lock(&intel_pstate_limits_lock);
driver_registered = false;
mutex_unlock(&intel_pstate_limits_lock);
cpufreq_unregister_driver(intel_pstate_driver);
intel_pstate_driver_cleanup();
return 0;
}
static ssize_t intel_pstate_show_status(char *buf)
{
if (!driver_registered)
return sprintf(buf, "off\n");
return sprintf(buf, "%s\n", intel_pstate_driver == &intel_pstate ?
"active" : "passive");
}
static int intel_pstate_update_status(const char *buf, size_t size)
{
int ret;
if (size == 3 && !strncmp(buf, "off", size))
return driver_registered ?
intel_pstate_unregister_driver() : -EINVAL;
if (size == 6 && !strncmp(buf, "active", size)) {
if (driver_registered) {
if (intel_pstate_driver == &intel_pstate)
return 0;
ret = intel_pstate_unregister_driver();
if (ret)
return ret;
}
intel_pstate_driver = &intel_pstate;
return intel_pstate_register_driver();
}
if (size == 7 && !strncmp(buf, "passive", size)) {
if (driver_registered) {
if (intel_pstate_driver != &intel_pstate)
return 0;
ret = intel_pstate_unregister_driver();
if (ret)
return ret;
}
intel_pstate_driver = &intel_cpufreq;
return intel_pstate_register_driver();
}
return -EINVAL;
}
static int no_load __initdata;
static int no_hwp __initdata;
static int hwp_only __initdata;
@ -2486,9 +2737,9 @@ static const struct x86_cpu_id hwp_support_ids[] __initconst = {
static int __init intel_pstate_init(void)
{
int cpu, rc = 0;
const struct x86_cpu_id *id;
struct cpu_defaults *cpu_def;
int rc = 0;
if (no_load)
return -ENODEV;
@ -2520,45 +2771,29 @@ hwp_cpu_matched:
if (intel_pstate_platform_pwr_mgmt_exists())
return -ENODEV;
if (!hwp_active && hwp_only)
return -ENOTSUPP;
pr_info("Intel P-state driver initializing\n");
all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
if (!all_cpu_data)
return -ENOMEM;
if (!hwp_active && hwp_only)
goto out;
intel_pstate_request_control_from_smm();
rc = cpufreq_register_driver(intel_pstate_driver);
if (rc)
goto out;
if (intel_pstate_driver == &intel_pstate && !hwp_active &&
pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
intel_pstate_debug_expose_params();
intel_pstate_sysfs_expose_params();
mutex_lock(&intel_pstate_driver_lock);
rc = intel_pstate_register_driver();
mutex_unlock(&intel_pstate_driver_lock);
if (rc)
return rc;
if (hwp_active)
pr_info("HWP enabled\n");
return rc;
out:
get_online_cpus();
for_each_online_cpu(cpu) {
if (all_cpu_data[cpu]) {
if (intel_pstate_driver == &intel_pstate)
intel_pstate_clear_update_util_hook(cpu);
kfree(all_cpu_data[cpu]);
}
}
put_online_cpus();
vfree(all_cpu_data);
return -ENODEV;
return 0;
}
device_initcall(intel_pstate_init);

52
drivers/cpufreq/powernv-cpufreq.c
View File

@ -144,6 +144,7 @@ static struct powernv_pstate_info {
unsigned int max;
unsigned int nominal;
unsigned int nr_pstates;
bool wof_enabled;
} powernv_pstate_info;
/* Use following macros for conversions between pstate_id and index */
@ -203,6 +204,7 @@ static int init_powernv_pstates(void)
const __be32 *pstate_ids, *pstate_freqs;
u32 len_ids, len_freqs;
u32 pstate_min, pstate_max, pstate_nominal;
u32 pstate_turbo, pstate_ultra_turbo;
power_mgt = of_find_node_by_path("/ibm,opal/power-mgt");
if (!power_mgt) {
@ -225,8 +227,29 @@ static int init_powernv_pstates(void)
pr_warn("ibm,pstate-nominal not found\n");
return -ENODEV;
}
if (of_property_read_u32(power_mgt, "ibm,pstate-ultra-turbo",
&pstate_ultra_turbo)) {
powernv_pstate_info.wof_enabled = false;
goto next;
}
if (of_property_read_u32(power_mgt, "ibm,pstate-turbo",
&pstate_turbo)) {
powernv_pstate_info.wof_enabled = false;
goto next;
}
if (pstate_turbo == pstate_ultra_turbo)
powernv_pstate_info.wof_enabled = false;
else
powernv_pstate_info.wof_enabled = true;
next:
pr_info("cpufreq pstate min %d nominal %d max %d\n", pstate_min,
pstate_nominal, pstate_max);
pr_info("Workload Optimized Frequency is %s in the platform\n",
(powernv_pstate_info.wof_enabled) ? "enabled" : "disabled");
pstate_ids = of_get_property(power_mgt, "ibm,pstate-ids", &len_ids);
if (!pstate_ids) {
@ -268,6 +291,13 @@ static int init_powernv_pstates(void)
powernv_pstate_info.nominal = i;
else if (id == pstate_min)
powernv_pstate_info.min = i;
if (powernv_pstate_info.wof_enabled && id == pstate_turbo) {
int j;
for (j = i - 1; j >= (int)powernv_pstate_info.max; j--)
powernv_freqs[j].flags = CPUFREQ_BOOST_FREQ;
}
}
/* End of list marker entry */
@ -305,9 +335,12 @@ static ssize_t cpuinfo_nominal_freq_show(struct cpufreq_policy *policy,
struct freq_attr cpufreq_freq_attr_cpuinfo_nominal_freq =
__ATTR_RO(cpuinfo_nominal_freq);
#define SCALING_BOOST_FREQS_ATTR_INDEX 2
static struct freq_attr *powernv_cpu_freq_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
&cpufreq_freq_attr_cpuinfo_nominal_freq,
&cpufreq_freq_attr_scaling_boost_freqs,
NULL,
};
@ -1013,11 +1046,22 @@ static int __init powernv_cpufreq_init(void)
register_reboot_notifier(&powernv_cpufreq_reboot_nb);
opal_message_notifier_register(OPAL_MSG_OCC, &powernv_cpufreq_opal_nb);
rc = cpufreq_register_driver(&powernv_cpufreq_driver);
if (!rc)
return 0;
if (powernv_pstate_info.wof_enabled)
powernv_cpufreq_driver.boost_enabled = true;
else
powernv_cpu_freq_attr[SCALING_BOOST_FREQS_ATTR_INDEX] = NULL;
pr_info("Failed to register the cpufreq driver (%d)\n", rc);
rc = cpufreq_register_driver(&powernv_cpufreq_driver);
if (rc) {
pr_info("Failed to register the cpufreq driver (%d)\n", rc);
goto cleanup_notifiers;
}
if (powernv_pstate_info.wof_enabled)
cpufreq_enable_boost_support();
return 0;
cleanup_notifiers:
unregister_all_notifiers();
clean_chip_info();
out:

3
drivers/cpufreq/ppc_cbe_cpufreq_pmi.c
View File

@ -100,9 +100,6 @@ static int pmi_notifier(struct notifier_block *nb,
/* Should this really be called for CPUFREQ_ADJUST and CPUFREQ_NOTIFY
* policy events?)
*/
if (event == CPUFREQ_START)
return 0;
node = cbe_cpu_to_node(policy->cpu);
pr_debug("got notified, event=%lu, node=%u\n", event, node);

148
drivers/cpufreq/qoriq-cpufreq.c
View File

@ -11,6 +11,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/cpufreq.h>
#include <linux/cpu_cooling.h>
#include <linux/errno.h>
@ -37,53 +38,20 @@ struct cpu_data {
struct thermal_cooling_device *cdev;
};
/*
* Don't use cpufreq on this SoC -- used when the SoC would have otherwise
* matched a more generic compatible.
*/
#define SOC_BLACKLIST 1
/**
* struct soc_data - SoC specific data
* @freq_mask: mask the disallowed frequencies
* @flag: unique flags
* @flags: SOC_xxx
*/
struct soc_data {
u32 freq_mask[4];
u32 flag;
u32 flags;
};
#define FREQ_MASK 1
/* see hardware specification for the allowed frqeuencies */
static const struct soc_data sdata[] = {
{ /* used by p2041 and p3041 */
.freq_mask = {0x8, 0x8, 0x2, 0x2},
.flag = FREQ_MASK,
},
{ /* used by p5020 */
.freq_mask = {0x8, 0x2},
.flag = FREQ_MASK,
},
{ /* used by p4080, p5040 */
.freq_mask = {0},
.flag = 0,
},
};
/*
* the minimum allowed core frequency, in Hz
* for chassis v1.0, >= platform frequency
* for chassis v2.0, >= platform frequency / 2
*/
static u32 min_cpufreq;
static const u32 *fmask;
#if defined(CONFIG_ARM)
static int get_cpu_physical_id(int cpu)
{
return topology_core_id(cpu);
}
#else
static int get_cpu_physical_id(int cpu)
{
return get_hard_smp_processor_id(cpu);
}
#endif
static u32 get_bus_freq(void)
{
struct device_node *soc;
@ -101,9 +69,10 @@ static u32 get_bus_freq(void)
return sysfreq;
}
static struct device_node *cpu_to_clk_node(int cpu)
static struct clk *cpu_to_clk(int cpu)
{
struct device_node *np, *clk_np;
struct device_node *np;
struct clk *clk;
if (!cpu_present(cpu))
return NULL;
@ -112,37 +81,28 @@ static struct device_node *cpu_to_clk_node(int cpu)
if (!np)
return NULL;
clk_np = of_parse_phandle(np, "clocks", 0);
if (!clk_np)
return NULL;
clk = of_clk_get(np, 0);
of_node_put(np);
return clk_np;
return clk;
}
/* traverse cpu nodes to get cpu mask of sharing clock wire */
static void set_affected_cpus(struct cpufreq_policy *policy)
{
struct device_node *np, *clk_np;
struct cpumask *dstp = policy->cpus;
struct clk *clk;
int i;
np = cpu_to_clk_node(policy->cpu);
if (!np)
return;
for_each_present_cpu(i) {
clk_np = cpu_to_clk_node(i);
if (!clk_np)
clk = cpu_to_clk(i);
if (IS_ERR(clk)) {
pr_err("%s: no clock for cpu %d\n", __func__, i);
continue;
}
if (clk_np == np)
if (clk_is_match(policy->clk, clk))
cpumask_set_cpu(i, dstp);
of_node_put(clk_np);
}
of_node_put(np);
}
/* reduce the duplicated frequencies in frequency table */
@ -198,10 +158,11 @@ static void freq_table_sort(struct cpufreq_frequency_table *freq_table,
static int qoriq_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
struct device_node *np, *pnode;
struct device_node *np;
int i, count, ret;
u32 freq, mask;
u32 freq;
struct clk *clk;
const struct clk_hw *hwclk;
struct cpufreq_frequency_table *table;
struct cpu_data *data;
unsigned int cpu = policy->cpu;
@ -221,17 +182,13 @@ static int qoriq_cpufreq_cpu_init(struct cpufreq_policy *policy)
goto err_nomem2;
}
pnode = of_parse_phandle(np, "clocks", 0);
if (!pnode) {
pr_err("%s: could not get clock information\n", __func__);
goto err_nomem2;
}
hwclk = __clk_get_hw(policy->clk);
count = clk_hw_get_num_parents(hwclk);
count = of_property_count_strings(pnode, "clock-names");
data->pclk = kcalloc(count, sizeof(struct clk *), GFP_KERNEL);
if (!data->pclk) {
pr_err("%s: no memory\n", __func__);
goto err_node;
goto err_nomem2;
}
table = kcalloc(count + 1, sizeof(*table), GFP_KERNEL);
@ -240,23 +197,11 @@ static int qoriq_cpufreq_cpu_init(struct cpufreq_policy *policy)
goto err_pclk;
}
if (fmask)
mask = fmask[get_cpu_physical_id(cpu)];
else
mask = 0x0;
for (i = 0; i < count; i++) {
clk = of_clk_get(pnode, i);
clk = clk_hw_get_parent_by_index(hwclk, i)->clk;
data->pclk[i] = clk;
freq = clk_get_rate(clk);
/*
* the clock is valid if its frequency is not masked
* and large than minimum allowed frequency.
*/
if (freq < min_cpufreq || (mask & (1 << i)))
table[i].frequency = CPUFREQ_ENTRY_INVALID;
else
table[i].frequency = freq / 1000;
table[i].frequency = freq / 1000;
table[i].driver_data = i;
}
freq_table_redup(table, count);
@ -282,7 +227,6 @@ static int qoriq_cpufreq_cpu_init(struct cpufreq_policy *policy)
policy->cpuinfo.transition_latency = u64temp + 1;
of_node_put(np);
of_node_put(pnode);
return 0;
@ -290,10 +234,7 @@ err_nomem1:
kfree(table);
err_pclk:
kfree(data->pclk);
err_node:
of_node_put(pnode);
err_nomem2:
policy->driver_data = NULL;
kfree(data);
err_np:
of_node_put(np);
@ -357,12 +298,25 @@ static struct cpufreq_driver qoriq_cpufreq_driver = {
.attr = cpufreq_generic_attr,
};
static const struct soc_data blacklist = {
.flags = SOC_BLACKLIST,
};
static const struct of_device_id node_matches[] __initconst = {
{ .compatible = "fsl,p2041-clockgen", .data = &sdata[0], },
{ .compatible = "fsl,p3041-clockgen", .data = &sdata[0], },
{ .compatible = "fsl,p5020-clockgen", .data = &sdata[1], },
{ .compatible = "fsl,p4080-clockgen", .data = &sdata[2], },
{ .compatible = "fsl,p5040-clockgen", .data = &sdata[2], },
/* e6500 cannot use cpufreq due to erratum A-008083 */
{ .compatible = "fsl,b4420-clockgen", &blacklist },
{ .compatible = "fsl,b4860-clockgen", &blacklist },
{ .compatible = "fsl,t2080-clockgen", &blacklist },
{ .compatible = "fsl,t4240-clockgen", &blacklist },
{ .compatible = "fsl,ls1012a-clockgen", },
{ .compatible = "fsl,ls1021a-clockgen", },
{ .compatible = "fsl,ls1043a-clockgen", },
{ .compatible = "fsl,ls1046a-clockgen", },
{ .compatible = "fsl,ls1088a-clockgen", },
{ .compatible = "fsl,ls2080a-clockgen", },
{ .compatible = "fsl,p4080-clockgen", },
{ .compatible = "fsl,qoriq-clockgen-1.0", },
{ .compatible = "fsl,qoriq-clockgen-2.0", },
{}
};
@ -380,16 +334,12 @@ static int __init qoriq_cpufreq_init(void)
match = of_match_node(node_matches, np);
data = match->data;
if (data) {
if (data->flag)
fmask = data->freq_mask;
min_cpufreq = get_bus_freq();
} else {
min_cpufreq = get_bus_freq() / 2;
}
of_node_put(np);
if (data && data->flags & SOC_BLACKLIST)
return -ENODEV;
ret = cpufreq_register_driver(&qoriq_cpufreq_driver);
if (!ret)
pr_info("Freescale QorIQ CPU frequency scaling driver\n");

1
drivers/cpufreq/s3c2416-cpufreq.c
View File

@ -400,7 +400,6 @@ static int s3c2416_cpufreq_driver_init(struct cpufreq_policy *policy)
rate = clk_get_rate(s3c_freq->hclk);
if (rate < 133 * 1000 * 1000) {
pr_err("cpufreq: HCLK not at 133MHz\n");
clk_put(s3c_freq->hclk);
ret = -EINVAL;
goto err_armclk;
}

268
drivers/cpufreq/ti-cpufreq.c Normal file
View File

@ -0,0 +1,268 @@
/*
* TI CPUFreq/OPP hw-supported driver
*
* Copyright (C) 2016-2017 Texas Instruments, Inc.
* Dave Gerlach <d-gerlach@ti.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/cpu.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pm_opp.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#define REVISION_MASK 0xF
#define REVISION_SHIFT 28
#define AM33XX_800M_ARM_MPU_MAX_FREQ 0x1E2F
#define AM43XX_600M_ARM_MPU_MAX_FREQ 0xFFA
#define DRA7_EFUSE_HAS_OD_MPU_OPP 11
#define DRA7_EFUSE_HAS_HIGH_MPU_OPP 15
#define DRA7_EFUSE_HAS_ALL_MPU_OPP 23
#define DRA7_EFUSE_NOM_MPU_OPP BIT(0)
#define DRA7_EFUSE_OD_MPU_OPP BIT(1)
#define DRA7_EFUSE_HIGH_MPU_OPP BIT(2)
#define VERSION_COUNT 2
struct ti_cpufreq_data;
struct ti_cpufreq_soc_data {
unsigned long (*efuse_xlate)(struct ti_cpufreq_data *opp_data,
unsigned long efuse);
unsigned long efuse_fallback;
unsigned long efuse_offset;
unsigned long efuse_mask;
unsigned long efuse_shift;
unsigned long rev_offset;
};
struct ti_cpufreq_data {
struct device *cpu_dev;
struct device_node *opp_node;
struct regmap *syscon;
const struct ti_cpufreq_soc_data *soc_data;
};
static unsigned long amx3_efuse_xlate(struct ti_cpufreq_data *opp_data,
unsigned long efuse)
{
if (!efuse)
efuse = opp_data->soc_data->efuse_fallback;
/* AM335x and AM437x use "OPP disable" bits, so invert */
return ~efuse;
}
static unsigned long dra7_efuse_xlate(struct ti_cpufreq_data *opp_data,
unsigned long efuse)
{
unsigned long calculated_efuse = DRA7_EFUSE_NOM_MPU_OPP;
/*
* The efuse on dra7 and am57 parts contains a specific
* value indicating the highest available OPP.
*/
switch (efuse) {
case DRA7_EFUSE_HAS_ALL_MPU_OPP:
case DRA7_EFUSE_HAS_HIGH_MPU_OPP:
calculated_efuse |= DRA7_EFUSE_HIGH_MPU_OPP;
case DRA7_EFUSE_HAS_OD_MPU_OPP:
calculated_efuse |= DRA7_EFUSE_OD_MPU_OPP;
}
return calculated_efuse;
}
static struct ti_cpufreq_soc_data am3x_soc_data = {
.efuse_xlate = amx3_efuse_xlate,
.efuse_fallback = AM33XX_800M_ARM_MPU_MAX_FREQ,
.efuse_offset = 0x07fc,
.efuse_mask = 0x1fff,
.rev_offset = 0x600,
};
static struct ti_cpufreq_soc_data am4x_soc_data = {
.efuse_xlate = amx3_efuse_xlate,
.efuse_fallback = AM43XX_600M_ARM_MPU_MAX_FREQ,
.efuse_offset = 0x0610,
.efuse_mask = 0x3f,
.rev_offset = 0x600,
};
static struct ti_cpufreq_soc_data dra7_soc_data = {
.efuse_xlate = dra7_efuse_xlate,
.efuse_offset = 0x020c,
.efuse_mask = 0xf80000,
.efuse_shift = 19,
.rev_offset = 0x204,
};
/**
* ti_cpufreq_get_efuse() - Parse and return efuse value present on SoC
* @opp_data: pointer to ti_cpufreq_data context
* @efuse_value: Set to the value parsed from efuse
*
* Returns error code if efuse not read properly.
*/
static int ti_cpufreq_get_efuse(struct ti_cpufreq_data *opp_data,
u32 *efuse_value)
{
struct device *dev = opp_data->cpu_dev;
u32 efuse;
int ret;
ret = regmap_read(opp_data->syscon, opp_data->soc_data->efuse_offset,
&efuse);
if (ret) {
dev_err(dev,
"Failed to read the efuse value from syscon: %d\n",
ret);
return ret;
}
efuse = (efuse & opp_data->soc_data->efuse_mask);
efuse >>= opp_data->soc_data->efuse_shift;
*efuse_value = opp_data->soc_data->efuse_xlate(opp_data, efuse);
return 0;
}
/**
* ti_cpufreq_get_rev() - Parse and return rev value present on SoC
* @opp_data: pointer to ti_cpufreq_data context
* @revision_value: Set to the value parsed from revision register
*
* Returns error code if revision not read properly.
*/
static int ti_cpufreq_get_rev(struct ti_cpufreq_data *opp_data,
u32 *revision_value)
{
struct device *dev = opp_data->cpu_dev;
u32 revision;
int ret;
ret = regmap_read(opp_data->syscon, opp_data->soc_data->rev_offset,
&revision);
if (ret) {
dev_err(dev,
"Failed to read the revision number from syscon: %d\n",
ret);
return ret;
}
*revision_value = BIT((revision >> REVISION_SHIFT) & REVISION_MASK);
return 0;
}
static int ti_cpufreq_setup_syscon_register(struct ti_cpufreq_data *opp_data)
{
struct device *dev = opp_data->cpu_dev;
struct device_node *np = opp_data->opp_node;
opp_data->syscon = syscon_regmap_lookup_by_phandle(np,
"syscon");
if (IS_ERR(opp_data->syscon)) {
dev_err(dev,
"\"syscon\" is missing, cannot use OPPv2 table.\n");
return PTR_ERR(opp_data->syscon);
}
return 0;
}
static const struct of_device_id ti_cpufreq_of_match[] = {
{ .compatible = "ti,am33xx", .data = &am3x_soc_data, },
{ .compatible = "ti,am4372", .data = &am4x_soc_data, },
{ .compatible = "ti,dra7", .data = &dra7_soc_data },
{},
};
static int ti_cpufreq_init(void)
{
u32 version[VERSION_COUNT];
struct device_node *np;
const struct of_device_id *match;
struct ti_cpufreq_data *opp_data;
int ret;
np = of_find_node_by_path("/");
match = of_match_node(ti_cpufreq_of_match, np);
if (!match)
return -ENODEV;
opp_data = kzalloc(sizeof(*opp_data), GFP_KERNEL);
if (!opp_data)
return -ENOMEM;
opp_data->soc_data = match->data;
opp_data->cpu_dev = get_cpu_device(0);
if (!opp_data->cpu_dev) {
pr_err("%s: Failed to get device for CPU0\n", __func__);
return -ENODEV;
}
opp_data->opp_node = dev_pm_opp_of_get_opp_desc_node(opp_data->cpu_dev);
if (!opp_data->opp_node) {
dev_info(opp_data->cpu_dev,
"OPP-v2 not supported, cpufreq-dt will attempt to use legacy tables.\n");
goto register_cpufreq_dt;
}
ret = ti_cpufreq_setup_syscon_register(opp_data);
if (ret)
goto fail_put_node;
/*
* OPPs determine whether or not they are supported based on
* two metrics:
* 0 - SoC Revision
* 1 - eFuse value
*/
ret = ti_cpufreq_get_rev(opp_data, &version[0]);
if (ret)
goto fail_put_node;
ret = ti_cpufreq_get_efuse(opp_data, &version[1]);
if (ret)
goto fail_put_node;
of_node_put(opp_data->opp_node);
ret = PTR_ERR_OR_ZERO(dev_pm_opp_set_supported_hw(opp_data->cpu_dev,
version, VERSION_COUNT));
if (ret) {
dev_err(opp_data->cpu_dev,
"Failed to set supported hardware\n");
goto fail_put_node;
}
register_cpufreq_dt:
platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
return 0;
fail_put_node:
of_node_put(opp_data->opp_node);
return ret;
}
device_initcall(ti_cpufreq_init);

7
include/linux/cpufreq.h
View File

@ -31,7 +31,7 @@
#define CPUFREQ_ETERNAL (-1)
#define CPUFREQ_NAME_LEN 16
/* Print length for names. Extra 1 space for accomodating '\n' in prints */
/* Print length for names. Extra 1 space for accommodating '\n' in prints */
#define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1)
struct cpufreq_governor;
@ -115,7 +115,7 @@ struct cpufreq_policy {
* guarantee that frequency can be changed on any CPU sharing the
* policy and that the change will affect all of the policy CPUs then.
* - fast_switch_enabled is to be set by governors that support fast
* freqnency switching with the help of cpufreq_enable_fast_switch().
* frequency switching with the help of cpufreq_enable_fast_switch().
*/
bool fast_switch_possible;
bool fast_switch_enabled;
@ -415,9 +415,6 @@ static inline void cpufreq_resume(void) {}
/* Policy Notifiers */
#define CPUFREQ_ADJUST (0)
#define CPUFREQ_NOTIFY (1)
#define CPUFREQ_START (2)
#define CPUFREQ_CREATE_POLICY (3)
#define CPUFREQ_REMOVE_POLICY (4)
#ifdef CONFIG_CPU_FREQ
int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);