Re: [PATCH V8 2/3] OPP: Introduce "required-opp" property
From: Viresh Kumar <viresh.kumar@linaro.org>
Date: 2017-12-22 05:28:37
Also in:
linux-devicetree, lkml
Subsystem:
generic pm domains, open firmware and flattened device tree bindings, operating performance points (opp), the rest · Maintainers:
Ulf Hansson, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Viresh Kumar, Nishanth Menon, Stephen Boyd, Linus Torvalds
On 18-12-17, 15:51, Viresh Kumar wrote:
Devices have inter-dependencies some times. For example a device that needs to run at 800 MHz, needs another device (e.g. Its power domain) to be configured at a particular operating performance point. This patch introduces a new property "required-opp" which can be present directly in a device's node (if it doesn't need to change its OPPs), or in device's OPP nodes. More details on the property can be seen in the binding itself.
This is slightly updated based on Rob and Ulf's comments. Will apply it to the OPP tree with below diff. -- viresh -------------------------8<------------------------- Subject: [PATCH] OPP: Introduce "required-opp" property Devices have inter-dependencies some times. For example a device that needs to run at 800 MHz, needs another device (e.g. Its power domain) to be configured at a particular operating performance point. This patch introduces a new property "required-opp" which can be present directly in a device's node (if it doesn't need to change its OPPs), or in device's OPP nodes. More details on the property can be seen in the binding itself. Reviewed-by: Ulf Hansson <redacted> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- Changes: - s/opp_table/opp-table for node names. - s/parent/power for domain alias. Documentation/devicetree/bindings/opp/opp.txt | 8 +++ .../devicetree/bindings/power/power_domain.txt | 59 ++++++++++++++++++++++ 2 files changed, 67 insertions(+)
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index a3953a1bb1a1..4e4f30288c8b 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt@@ -159,6 +159,14 @@ properties. - status: Marks the node enabled/disabled. +- required-opp: This contains phandle to an OPP node in another device's OPP + table. It may contain an array of phandles, where each phandle points to an + OPP of a different device. It should not contain multiple phandles to the OPP + nodes in the same OPP table. This specifies the minimum required OPP of the + device(s), whose OPP's phandle is present in this property, for the + functioning of the current device at the current OPP (where this property is + present). + Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together. / {
diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt
index 61549840ab3b..f3355313c020 100644
--- a/Documentation/devicetree/bindings/power/power_domain.txt
+++ b/Documentation/devicetree/bindings/power/power_domain.txt@@ -126,4 +126,63 @@ The node above defines a typical PM domain consumer device, which is located inside a PM domain with index 0 of a power controller represented by a node with the label "power". +Optional properties: +- required-opp: This contains phandle to an OPP node in another device's OPP + table. It may contain an array of phandles, where each phandle points to an + OPP of a different device. It should not contain multiple phandles to the OPP + nodes in the same OPP table. This specifies the minimum required OPP of the + device(s), whose OPP's phandle is present in this property, for the + functioning of the current device at the current OPP (where this property is + present). + +Example: +- OPP table for domain provider that provides two domains. + + domain0_opp_table: opp-table0 { + compatible = "operating-points-v2"; + + domain0_opp_0: opp-1000000000 { + opp-hz = /bits/ 64 <1000000000>; + opp-microvolt = <975000 970000 985000>; + }; + domain0_opp_1: opp-1100000000 { + opp-hz = /bits/ 64 <1100000000>; + opp-microvolt = <1000000 980000 1010000>; + }; + }; + + domain1_opp_table: opp-table1 { + compatible = "operating-points-v2"; + + domain1_opp_0: opp-1200000000 { + opp-hz = /bits/ 64 <1200000000>; + opp-microvolt = <975000 970000 985000>; + }; + domain1_opp_1: opp-1300000000 { + opp-hz = /bits/ 64 <1300000000>; + opp-microvolt = <1000000 980000 1010000>; + }; + }; + + power: power-controller@12340000 { + compatible = "foo,power-controller"; + reg = <0x12340000 0x1000>; + #power-domain-cells = <1>; + operating-points-v2 = <&domain0_opp_table>, <&domain1_opp_table>; + }; + + leaky-device0@12350000 { + compatible = "foo,i-leak-current"; + reg = <0x12350000 0x1000>; + power-domains = <&power 0>; + required-opp = <&domain0_opp_0>; + }; + + leaky-device1@12350000 { + compatible = "foo,i-leak-current"; + reg = <0x12350000 0x1000>; + power-domains = <&power 1>; + required-opp = <&domain1_opp_1>; + }; + [1]. Documentation/devicetree/bindings/power/domain-idle-state.txt