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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-06-03 17:03:27 +0400
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-06-03 17:03:27 +0400
commit5ece2399181a5abaf42a4cb607463770686778e6 (patch)
tree5c789755fce670511f2ac1bc3eebf39e26ed1724 /Documentation
parentbf8102228a8bf053051f311e5486042fe0542894 (diff)
parent8d65775d17941d6d41f5913fc6a99a134c588e01 (diff)
downloadlinux-5ece2399181a5abaf42a4cb607463770686778e6.tar.xz
Merge back earlier cpufreq material.
Conflicts: arch/mips/loongson/lemote-2f/clock.c drivers/cpufreq/intel_pstate.c
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-devices-system-cpu4
-rw-r--r--Documentation/cpu-freq/core.txt29
-rw-r--r--Documentation/cpu-freq/cpu-drivers.txt19
-rw-r--r--Documentation/cpu-freq/index.txt4
-rw-r--r--Documentation/power/opp.txt40
5 files changed, 57 insertions, 39 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index d5a0d33c571f..acb9bfc89b48 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -128,7 +128,7 @@ Description: Discover cpuidle policy and mechanism
What: /sys/devices/system/cpu/cpu#/cpufreq/*
Date: pre-git history
-Contact: cpufreq@vger.kernel.org
+Contact: linux-pm@vger.kernel.org
Description: Discover and change clock speed of CPUs
Clock scaling allows you to change the clock speed of the
@@ -146,7 +146,7 @@ Description: Discover and change clock speed of CPUs
What: /sys/devices/system/cpu/cpu#/cpufreq/freqdomain_cpus
Date: June 2013
-Contact: cpufreq@vger.kernel.org
+Contact: linux-pm@vger.kernel.org
Description: Discover CPUs in the same CPU frequency coordination domain
freqdomain_cpus is the list of CPUs (online+offline) that share
diff --git a/Documentation/cpu-freq/core.txt b/Documentation/cpu-freq/core.txt
index 0060d76b445f..70933eadc308 100644
--- a/Documentation/cpu-freq/core.txt
+++ b/Documentation/cpu-freq/core.txt
@@ -20,6 +20,7 @@ Contents:
---------
1. CPUFreq core and interfaces
2. CPUFreq notifiers
+3. CPUFreq Table Generation with Operating Performance Point (OPP)
1. General Information
=======================
@@ -92,3 +93,31 @@ values:
cpu - number of the affected CPU
old - old frequency
new - new frequency
+
+3. CPUFreq Table Generation with Operating Performance Point (OPP)
+==================================================================
+For details about OPP, see Documentation/power/opp.txt
+
+dev_pm_opp_init_cpufreq_table - cpufreq framework typically is initialized with
+ cpufreq_frequency_table_cpuinfo which is provided with the list of
+ frequencies that are available for operation. This function provides
+ a ready to use conversion routine to translate the OPP layer's internal
+ information about the available frequencies into a format readily
+ providable to cpufreq.
+
+ WARNING: Do not use this function in interrupt context.
+
+ Example:
+ soc_pm_init()
+ {
+ /* Do things */
+ r = dev_pm_opp_init_cpufreq_table(dev, &freq_table);
+ if (!r)
+ cpufreq_frequency_table_cpuinfo(policy, freq_table);
+ /* Do other things */
+ }
+
+ NOTE: This function is available only if CONFIG_CPU_FREQ is enabled in
+ addition to CONFIG_PM_OPP.
+
+dev_pm_opp_free_cpufreq_table - Free up the table allocated by dev_pm_opp_init_cpufreq_table
diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt
index 48da5fdcb9f1..b045fe54986a 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -228,3 +228,22 @@ is the corresponding frequency table helper for the ->target
stage. Just pass the values to this function, and the unsigned int
index returns the number 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,
+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.
+
+For example:
+
+ struct cpufreq_frequency_table *pos, *driver_freq_table;
+
+ cpufreq_for_each_entry(pos, driver_freq_table) {
+ /* Do something with pos */
+ pos->frequency = ...
+ }
diff --git a/Documentation/cpu-freq/index.txt b/Documentation/cpu-freq/index.txt
index 3d0b915035b9..dc024ab4054f 100644
--- a/Documentation/cpu-freq/index.txt
+++ b/Documentation/cpu-freq/index.txt
@@ -35,8 +35,8 @@ 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 cpufreq@vger.kernel.org, to subscribe go to
-http://vger.kernel.org/vger-lists.html#cpufreq and follow the
+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.
Links
diff --git a/Documentation/power/opp.txt b/Documentation/power/opp.txt
index b8a907dc0169..a9adad828cdc 100644
--- a/Documentation/power/opp.txt
+++ b/Documentation/power/opp.txt
@@ -10,8 +10,7 @@ Contents
3. OPP Search Functions
4. OPP Availability Control Functions
5. OPP Data Retrieval Functions
-6. Cpufreq Table Generation
-7. Data Structures
+6. Data Structures
1. Introduction
===============
@@ -72,7 +71,6 @@ operations until that OPP could be re-enabled if possible.
OPP library facilitates this concept in it's implementation. The following
operational functions operate only on available opps:
opp_find_freq_{ceil, floor}, dev_pm_opp_get_voltage, dev_pm_opp_get_freq, dev_pm_opp_get_opp_count
-and dev_pm_opp_init_cpufreq_table
dev_pm_opp_find_freq_exact is meant to be used to find the opp pointer which can then
be used for dev_pm_opp_enable/disable functions to make an opp available as required.
@@ -96,10 +94,9 @@ using RCU read locks. The opp_find_freq_{exact,ceil,floor},
opp_get_{voltage, freq, opp_count} fall into this category.
opp_{add,enable,disable} are updaters which use mutex and implement it's own
-RCU locking mechanisms. dev_pm_opp_init_cpufreq_table acts as an updater and uses
-mutex to implment RCU updater strategy. These functions should *NOT* be called
-under RCU locks and other contexts that prevent blocking functions in RCU or
-mutex operations from working.
+RCU locking mechanisms. These functions should *NOT* be called under RCU locks
+and other contexts that prevent blocking functions in RCU or mutex operations
+from working.
2. Initial OPP List Registration
================================
@@ -311,34 +308,7 @@ dev_pm_opp_get_opp_count - Retrieve the number of available opps for a device
/* Do other things */
}
-6. Cpufreq Table Generation
-===========================
-dev_pm_opp_init_cpufreq_table - cpufreq framework typically is initialized with
- cpufreq_frequency_table_cpuinfo which is provided with the list of
- frequencies that are available for operation. This function provides
- a ready to use conversion routine to translate the OPP layer's internal
- information about the available frequencies into a format readily
- providable to cpufreq.
-
- WARNING: Do not use this function in interrupt context.
-
- Example:
- soc_pm_init()
- {
- /* Do things */
- r = dev_pm_opp_init_cpufreq_table(dev, &freq_table);
- if (!r)
- cpufreq_frequency_table_cpuinfo(policy, freq_table);
- /* Do other things */
- }
-
- NOTE: This function is available only if CONFIG_CPU_FREQ is enabled in
- addition to CONFIG_PM as power management feature is required to
- dynamically scale voltage and frequency in a system.
-
-dev_pm_opp_free_cpufreq_table - Free up the table allocated by dev_pm_opp_init_cpufreq_table
-
-7. Data Structures
+6. Data Structures
==================
Typically an SoC contains multiple voltage domains which are variable. Each
domain is represented by a device pointer. The relationship to OPP can be