path: root/Documentation/power
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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-06-03 23:13:20 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-06-03 23:13:20 +0200
commit057beb1de54d33ecfd3397ed219b1f4518e3b470 (patch)
tree7c67e9d8c88093a3d551111e56401826a964ffba /Documentation/power
parent42a09284fab8abc15c8554f2e2aa2368161c77c6 (diff)
parent5ece2399181a5abaf42a4cb607463770686778e6 (diff)
Merge branch 'pm-cpufreq'
* pm-cpufreq: (28 commits) cpufreq: handle calls to ->target_index() in separate routine cpufreq: s5pv210: drop check for CONFIG_PM_VERBOSE cpufreq: intel_pstate: Remove unused member name of cpudata cpufreq: Break out early when frequency equals target_freq cpufreq: Tegra: drop wrapper around tegra_update_cpu_speed() cpufreq: imx6q: Remove unused include cpufreq: imx6q: Drop devm_clk/regulator_get usage cpufreq: powernow-k8: Suppress checkpatch warnings cpufreq: powernv: make local function static cpufreq: Enable big.LITTLE cpufreq driver on arm64 cpufreq: nforce2: remove DEFINE_PCI_DEVICE_TABLE macro intel_pstate: Add CPU IDs for Broadwell processors cpufreq: Fix build error on some platforms that use cpufreq_for_each_* PM / OPP: Move cpufreq specific OPP functions out of generic OPP library PM / OPP: Remove cpufreq wrapper dependency on internal data organization cpufreq: Catch double invocations of cpufreq_freq_transition_begin/end intel_pstate: Remove sample parameter in intel_pstate_calc_busy cpufreq: Kconfig: Fix spelling errors cpufreq: Make linux-pm@vger.kernel.org official mailing list cpufreq: exynos: Use dev_err/info function instead of pr_err/info ...
Diffstat (limited to 'Documentation/power')
1 files changed, 5 insertions, 35 deletions
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

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