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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-23 14:18:07 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-23 14:18:07 -0700
commit43c9fad942b5afb9e03801c0721d83160fa5b0dd (patch)
treec2002d29d5579196b0f54fd78e47ab02efced394 /Documentation/devicetree
parentMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial (diff)
parentMerge branch 'pm-cpuidle' (diff)
downloadlinux-dev-43c9fad942b5afb9e03801c0721d83160fa5b0dd.tar.xz
linux-dev-43c9fad942b5afb9e03801c0721d83160fa5b0dd.zip
Merge tag 'pm+acpi-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI updates from Rafael Wysocki: "The rework of backlight interface selection API from Hans de Goede stands out from the number of commits and the number of affected places perspective. The cpufreq core fixes from Viresh Kumar are quite significant too as far as the number of commits goes and because they should reduce CPU online/offline overhead quite a bit in the majority of cases. From the new featues point of view, the ACPICA update (to upstream revision 20150515) adding support for new ACPI 6 material to ACPICA is the one that matters the most as some new significant features will be based on it going forward. Also included is an update of the ACPI device power management core to follow ACPI 6 (which in turn reflects the Windows' device PM implementation), a PM core extension to support wakeup interrupts in a more generic way and support for the ACPI _CCA device configuration object. The rest is mostly fixes and cleanups all over and some documentation updates, including new DT bindings for Operating Performance Points. There is one fix for a regression introduced in the 4.1 cycle, but it adds quite a number of lines of code, it wasn't really ready before Thursday and you were on vacation, so I refrained from pushing it on the last minute for 4.1. Specifics: - ACPICA update to upstream revision 20150515 including basic support for ACPI 6 features: new ACPI tables introduced by ACPI 6 (STAO, XENV, WPBT, NFIT, IORT), changes related to the other tables (DTRM, FADT, LPIT, MADT), new predefined names (_BTH, _CR3, _DSD, _LPI, _MTL, _PRR, _RDI, _RST, _TFP, _TSN), fixes and cleanups (Bob Moore, Lv Zheng). - ACPI device power management core code update to follow ACPI 6 which reflects the ACPI device power management implementation in Windows (Rafael J Wysocki). - rework of the backlight interface selection logic to reduce the number of kernel command line options and improve the handling of DMI quirks that may be involved in that and to make the code generally more straightforward (Hans de Goede). - fixes for the ACPI Embedded Controller (EC) driver related to the handling of EC transactions (Lv Zheng). - fix for a regression related to the ACPI resources management and resulting from a recent change of ACPI initialization code ordering (Rafael J Wysocki). - fix for a system initialization regression related to ACPI introduced during the 3.14 cycle and caused by running the code that switches the platform over to the ACPI mode too early in the initialization sequence (Rafael J Wysocki). - support for the ACPI _CCA device configuration object related to DMA cache coherence (Suravee Suthikulpanit). - ACPI/APEI fixes and cleanups (Jiri Kosina, Borislav Petkov). - ACPI battery driver cleanups (Luis Henriques, Mathias Krause). - ACPI processor driver cleanups (Hanjun Guo). - cleanups and documentation update related to the ACPI device properties interface based on _DSD (Rafael J Wysocki). - ACPI device power management fixes (Rafael J Wysocki). - assorted cleanups related to ACPI (Dominik Brodowski, Fabian Frederick, Lorenzo Pieralisi, Mathias Krause, Rafael J Wysocki). - fix for a long-standing issue causing General Protection Faults to be generated occasionally on return to user space after resume from ACPI-based suspend-to-RAM on 32-bit x86 (Ingo Molnar). - fix to make the suspend core code return -EBUSY consistently in all cases when system suspend is aborted due to wakeup detection (Ruchi Kandoi). - support for automated device wakeup IRQ handling allowing drivers to make their PM support more starightforward (Tony Lindgren). - new tracepoints for suspend-to-idle tracing and rework of the prepare/complete callbacks tracing in the PM core (Todd E Brandt, Rafael J Wysocki). - wakeup sources framework enhancements (Jin Qian). - new macro for noirq system PM callbacks (Grygorii Strashko). - assorted cleanups related to system suspend (Rafael J Wysocki). - cpuidle core cleanups to make the code more efficient (Rafael J Wysocki). - powernv/pseries cpuidle driver update (Shilpasri G Bhat). - cpufreq core fixes related to CPU online/offline that should reduce the overhead of these operations quite a bit, unless the CPU in question is physically going away (Viresh Kumar, Saravana Kannan). - serialization of cpufreq governor callbacks to avoid race conditions in some cases (Viresh Kumar). - intel_pstate driver fixes and cleanups (Doug Smythies, Prarit Bhargava, Joe Konno). - cpufreq driver (arm_big_little, cpufreq-dt, qoriq) updates (Sudeep Holla, Felipe Balbi, Tang Yuantian). - assorted cleanups in cpufreq drivers and core (Shailendra Verma, Fabian Frederick, Wang Long). - new Device Tree bindings for representing Operating Performance Points (Viresh Kumar). - updates for the common clock operations support code in the PM core (Rajendra Nayak, Geert Uytterhoeven). - PM domains core code update (Geert Uytterhoeven). - Intel Knights Landing support for the RAPL (Running Average Power Limit) power capping driver (Dasaratharaman Chandramouli). - fixes related to the floor frequency setting on Atom SoCs in the RAPL power capping driver (Ajay Thomas). - runtime PM framework documentation update (Ben Dooks). - cpupower tool fix (Herton R Krzesinski)" * tag 'pm+acpi-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (194 commits) cpuidle: powernv/pseries: Auto-promotion of snooze to deeper idle state x86: Load __USER_DS into DS/ES after resume PM / OPP: Add binding for 'opp-suspend' PM / OPP: Allow multiple OPP tables to be passed via DT PM / OPP: Add new bindings to address shortcomings of existing bindings ACPI: Constify ACPI device IDs in documentation ACPI / enumeration: Document the rules regarding the PRP0001 device ID ACPI / video: Make acpi_video_unregister_backlight() private acpi-video-detect: Remove old API toshiba-acpi: Port to new backlight interface selection API thinkpad-acpi: Port to new backlight interface selection API sony-laptop: Port to new backlight interface selection API samsung-laptop: Port to new backlight interface selection API msi-wmi: Port to new backlight interface selection API msi-laptop: Port to new backlight interface selection API intel-oaktrail: Port to new backlight interface selection API ideapad-laptop: Port to new backlight interface selection API fujitsu-laptop: Port to new backlight interface selection API eeepc-laptop: Port to new backlight interface selection API dell-wmi: Port to new backlight interface selection API ...
Diffstat (limited to 'Documentation/devicetree')
-rw-r--r--Documentation/devicetree/bindings/power/opp.txt448
1 files changed, 444 insertions, 4 deletions
diff --git a/Documentation/devicetree/bindings/power/opp.txt b/Documentation/devicetree/bindings/power/opp.txt
index 74499e5033fc..0d5e7c978121 100644
--- a/Documentation/devicetree/bindings/power/opp.txt
+++ b/Documentation/devicetree/bindings/power/opp.txt
@@ -1,8 +1,19 @@
-* Generic OPP Interface
+Generic OPP (Operating Performance Points) Bindings
+----------------------------------------------------
-SoCs have a standard set of tuples consisting of frequency and
-voltage pairs that the device will support per voltage domain. These
-are called Operating Performance Points or OPPs.
+Devices work at voltage-current-frequency combinations and some implementations
+have the liberty of choosing these. These combinations are called Operating
+Performance Points aka OPPs. This document defines bindings for these OPPs
+applicable across wide range of devices. For illustration purpose, this document
+uses CPU as a device.
+
+This document contain multiple versions of OPP binding and only one of them
+should be used per device.
+
+Binding 1: operating-points
+============================
+
+This binding only supports voltage-frequency pairs.
Properties:
- operating-points: An array of 2-tuples items, and each item consists
@@ -23,3 +34,432 @@ cpu@0 {
198000 850000
>;
};
+
+
+Binding 2: operating-points-v2
+============================
+
+* Property: operating-points-v2
+
+Devices supporting OPPs must set their "operating-points-v2" property with
+phandle to a OPP table in their DT node. The OPP core will use this phandle to
+find the operating points for the device.
+
+Devices may want to choose OPP tables at runtime and so can provide a list of
+phandles here. But only *one* of them should be chosen at runtime. This must be
+accompanied by a corresponding "operating-points-names" property, to uniquely
+identify the OPP tables.
+
+If required, this can be extended for SoC vendor specfic bindings. Such bindings
+should be documented as Documentation/devicetree/bindings/power/<vendor>-opp.txt
+and should have a compatible description like: "operating-points-v2-<vendor>".
+
+Optional properties:
+- operating-points-names: Names of OPP tables (required if multiple OPP
+ tables are present), to uniquely identify them. The same list must be present
+ for all the CPUs which are sharing clock/voltage rails and hence the OPP
+ tables.
+
+* OPP Table Node
+
+This describes the OPPs belonging to a device. This node can have following
+properties:
+
+Required properties:
+- compatible: Allow OPPs to express their compatibility. It should be:
+ "operating-points-v2".
+
+- OPP nodes: One or more OPP nodes describing voltage-current-frequency
+ combinations. Their name isn't significant but their phandle can be used to
+ reference an OPP.
+
+Optional properties:
+- opp-shared: Indicates that device nodes using this OPP Table Node's phandle
+ switch their DVFS state together, i.e. they share clock/voltage/current lines.
+ Missing property means devices have independent clock/voltage/current lines,
+ but they share OPP tables.
+
+- status: Marks the OPP table enabled/disabled.
+
+
+* OPP Node
+
+This defines voltage-current-frequency combinations along with other related
+properties.
+
+Required properties:
+- opp-hz: Frequency in Hz
+
+Optional properties:
+- opp-microvolt: voltage in micro Volts.
+
+ A single regulator's voltage is specified with an array of size one or three.
+ Single entry is for target voltage and three entries are for <target min max>
+ voltages.
+
+ Entries for multiple regulators must be present in the same order as
+ regulators are specified in device's DT node.
+
+- opp-microamp: The maximum current drawn by the device in microamperes
+ considering system specific parameters (such as transients, process, aging,
+ maximum operating temperature range etc.) as necessary. This may be used to
+ set the most efficient regulator operating mode.
+
+ Should only be set if opp-microvolt is set for the OPP.
+
+ Entries for multiple regulators must be present in the same order as
+ regulators are specified in device's DT node. If this property isn't required
+ for few regulators, then this should be marked as zero for them. If it isn't
+ required for any regulator, then this property need not be present.
+
+- clock-latency-ns: Specifies the maximum possible transition latency (in
+ nanoseconds) for switching to this OPP from any other OPP.
+
+- turbo-mode: Marks the OPP to be used only for turbo modes. Turbo mode is
+ available on some platforms, where the device can run over its operating
+ frequency for a short duration of time limited by the device's power, current
+ and thermal limits.
+
+- opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
+ the table should have this.
+
+- status: Marks the node enabled/disabled.
+
+Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "arm,cortex-a9";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+
+ cpu@1 {
+ compatible = "arm,cortex-a9";
+ reg = <1>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+ };
+
+ cpu0_opp_table: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp00 {
+ opp-hz = <1000000000>;
+ opp-microvolt = <970000 975000 985000>;
+ opp-microamp = <70000>;
+ clock-latency-ns = <300000>;
+ opp-suspend;
+ };
+ opp01 {
+ opp-hz = <1100000000>;
+ opp-microvolt = <980000 1000000 1010000>;
+ opp-microamp = <80000>;
+ clock-latency-ns = <310000>;
+ };
+ opp02 {
+ opp-hz = <1200000000>;
+ opp-microvolt = <1025000>;
+ clock-latency-ns = <290000>;
+ turbo-mode;
+ };
+ };
+};
+
+Example 2: Single cluster, Quad-core Qualcom-krait, switches DVFS states
+independently.
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "qcom,krait";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+
+ cpu@1 {
+ compatible = "qcom,krait";
+ reg = <1>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 1>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply1>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+
+ cpu@2 {
+ compatible = "qcom,krait";
+ reg = <2>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 2>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply2>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+
+ cpu@3 {
+ compatible = "qcom,krait";
+ reg = <3>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 3>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply3>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+ };
+
+ cpu_opp_table: opp_table {
+ compatible = "operating-points-v2";
+
+ /*
+ * Missing opp-shared property means CPUs switch DVFS states
+ * independently.
+ */
+
+ opp00 {
+ opp-hz = <1000000000>;
+ opp-microvolt = <970000 975000 985000>;
+ opp-microamp = <70000>;
+ clock-latency-ns = <300000>;
+ opp-suspend;
+ };
+ opp01 {
+ opp-hz = <1100000000>;
+ opp-microvolt = <980000 1000000 1010000>;
+ opp-microamp = <80000>;
+ clock-latency-ns = <310000>;
+ };
+ opp02 {
+ opp-hz = <1200000000>;
+ opp-microvolt = <1025000>;
+ opp-microamp = <90000;
+ lock-latency-ns = <290000>;
+ turbo-mode;
+ };
+ };
+};
+
+Example 3: Dual-cluster, Dual-core per cluster. CPUs within a cluster switch
+DVFS state together.
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "arm,cortex-a7";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cluster0_opp>;
+ };
+
+ cpu@1 {
+ compatible = "arm,cortex-a7";
+ reg = <1>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cluster0_opp>;
+ };
+
+ cpu@100 {
+ compatible = "arm,cortex-a15";
+ reg = <100>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 1>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply1>;
+ operating-points-v2 = <&cluster1_opp>;
+ };
+
+ cpu@101 {
+ compatible = "arm,cortex-a15";
+ reg = <101>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 1>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply1>;
+ operating-points-v2 = <&cluster1_opp>;
+ };
+ };
+
+ cluster0_opp: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp00 {
+ opp-hz = <1000000000>;
+ opp-microvolt = <970000 975000 985000>;
+ opp-microamp = <70000>;
+ clock-latency-ns = <300000>;
+ opp-suspend;
+ };
+ opp01 {
+ opp-hz = <1100000000>;
+ opp-microvolt = <980000 1000000 1010000>;
+ opp-microamp = <80000>;
+ clock-latency-ns = <310000>;
+ };
+ opp02 {
+ opp-hz = <1200000000>;
+ opp-microvolt = <1025000>;
+ opp-microamp = <90000>;
+ clock-latency-ns = <290000>;
+ turbo-mode;
+ };
+ };
+
+ cluster1_opp: opp_table1 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp10 {
+ opp-hz = <1300000000>;
+ opp-microvolt = <1045000 1050000 1055000>;
+ opp-microamp = <95000>;
+ clock-latency-ns = <400000>;
+ opp-suspend;
+ };
+ opp11 {
+ opp-hz = <1400000000>;
+ opp-microvolt = <1075000>;
+ opp-microamp = <100000>;
+ clock-latency-ns = <400000>;
+ };
+ opp12 {
+ opp-hz = <1500000000>;
+ opp-microvolt = <1010000 1100000 1110000>;
+ opp-microamp = <95000>;
+ clock-latency-ns = <400000>;
+ turbo-mode;
+ };
+ };
+};
+
+Example 4: Handling multiple regulators
+
+/ {
+ cpus {
+ cpu@0 {
+ compatible = "arm,cortex-a7";
+ ...
+
+ cpu-supply = <&cpu_supply0>, <&cpu_supply1>, <&cpu_supply2>;
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+ };
+
+ cpu0_opp_table: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp00 {
+ opp-hz = <1000000000>;
+ opp-microvolt = <970000>, /* Supply 0 */
+ <960000>, /* Supply 1 */
+ <960000>; /* Supply 2 */
+ opp-microamp = <70000>, /* Supply 0 */
+ <70000>, /* Supply 1 */
+ <70000>; /* Supply 2 */
+ clock-latency-ns = <300000>;
+ };
+
+ /* OR */
+
+ opp00 {
+ opp-hz = <1000000000>;
+ opp-microvolt = <970000 975000 985000>, /* Supply 0 */
+ <960000 965000 975000>, /* Supply 1 */
+ <960000 965000 975000>; /* Supply 2 */
+ opp-microamp = <70000>, /* Supply 0 */
+ <70000>, /* Supply 1 */
+ <70000>; /* Supply 2 */
+ clock-latency-ns = <300000>;
+ };
+
+ /* OR */
+
+ opp00 {
+ opp-hz = <1000000000>;
+ opp-microvolt = <970000 975000 985000>, /* Supply 0 */
+ <960000 965000 975000>, /* Supply 1 */
+ <960000 965000 975000>; /* Supply 2 */
+ opp-microamp = <70000>, /* Supply 0 */
+ <0>, /* Supply 1 doesn't need this */
+ <70000>; /* Supply 2 */
+ clock-latency-ns = <300000>;
+ };
+ };
+};
+
+Example 5: Multiple OPP tables
+
+/ {
+ cpus {
+ cpu@0 {
+ compatible = "arm,cortex-a7";
+ ...
+
+ cpu-supply = <&cpu_supply>
+ operating-points-v2 = <&cpu0_opp_table_slow>, <&cpu0_opp_table_fast>;
+ operating-points-names = "slow", "fast";
+ };
+ };
+
+ cpu0_opp_table_slow: opp_table_slow {
+ compatible = "operating-points-v2";
+ status = "okay";
+ opp-shared;
+
+ opp00 {
+ opp-hz = <600000000>;
+ ...
+ };
+
+ opp01 {
+ opp-hz = <800000000>;
+ ...
+ };
+ };
+
+ cpu0_opp_table_fast: opp_table_fast {
+ compatible = "operating-points-v2";
+ status = "okay";
+ opp-shared;
+
+ opp10 {
+ opp-hz = <1000000000>;
+ ...
+ };
+
+ opp11 {
+ opp-hz = <1100000000>;
+ ...
+ };
+ };
+};