Merge branch 'pm-cpufreq'

* 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
  ...

8 files changed, 487 insertions, 286 deletions

diff --git a/Documentation/cpu-freq/core.txt b/Documentation/cpu-freq/core.txt
index 4bc7287806de..978463a7c81e 100644
--- a/Documentation/cpu-freq/core.txt
+++ b/Documentation/cpu-freq/core.txt
@@ -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)
 ==================================================================
diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt
index 772b94fde264..f71e6be26b83 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -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.
-
-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.
-
-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.
-
-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.
+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(), 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.
+
+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.
+
+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.
diff --git a/Documentation/cpu-freq/cpufreq-stats.txt b/Documentation/cpu-freq/cpufreq-stats.txt
index 3c355f6ad834..2bbe207354ed 100644
--- a/Documentation/cpu-freq/cpufreq-stats.txt
+++ b/Documentation/cpu-freq/cpufreq-stats.txt
@@ -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.
-
-
-
-
diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt
index c15aa75f5227..61b3184b6c24 100644
--- a/Documentation/cpu-freq/governors.txt
+++ b/Documentation/cpu-freq/governors.txt
@@ -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:
-
-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
-
-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.
-
-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.  
-
-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.
+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.
+
+Sysfs files:
+
+* 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
+
+* 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.
+
+* 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:
-
-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.
-
-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.
+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.
+
+* 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].
+
 
 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/
 
diff --git a/Documentation/cpu-freq/index.txt b/Documentation/cpu-freq/index.txt
index dc024ab4054f..ef1d39247b05 100644
--- a/Documentation/cpu-freq/index.txt
+++ b/Documentation/cpu-freq/index.txt
@@ -18,16 +18,29 @@
 
 Documents in this directory:
 ----------------------------
+
+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
+			of CPUFreq notifiers.
+
+cpu-drivers.txt -	How to implement a new cpufreq processor driver.
 
-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
diff --git a/Documentation/cpu-freq/intel-pstate.txt b/Documentation/cpu-freq/intel-pstate.txt
index 1953994ef5e6..3fdcdfd968ba 100644
--- a/Documentation/cpu-freq/intel-pstate.txt
+++ b/Documentation/cpu-freq/intel-pstate.txt
@@ -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.
diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt
index 109e97bbab77..107f6fdd7d14 100644
--- a/Documentation/cpu-freq/user-guide.txt
+++ b/Documentation/cpu-freq/user-guide.txt
@@ -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
diff --git a/Documentation/devicetree/bindings/cpufreq/ti-cpufreq.txt b/Documentation/devicetree/bindings/cpufreq/ti-cpufreq.txt
new file mode 100644
index 000000000000..ba0e15ad5bd9
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/ti-cpufreq.txt
@@ -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>;
+	};
+};