aboutsummaryrefslogtreecommitdiff
path: root/Documentation/cpu-freq/core.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/cpu-freq/core.txt')
-rw-r--r--Documentation/cpu-freq/core.txt29
1 files changed, 29 insertions, 0 deletions
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