diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/ABI/testing/sysfs-devices-system-cpu | 4 | ||||
-rw-r--r-- | Documentation/cpu-freq/core.txt | 29 | ||||
-rw-r--r-- | Documentation/cpu-freq/cpu-drivers.txt | 19 | ||||
-rw-r--r-- | Documentation/cpu-freq/index.txt | 4 | ||||
-rw-r--r-- | Documentation/power/opp.txt | 40 |
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 d5a0d33c571..acb9bfc89b4 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 0060d76b445..70933eadc30 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 48da5fdcb9f..b045fe54986 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 3d0b915035b..dc024ab4054 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 b8a907dc016..a9adad828cd 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 |