[PATCH v8 01/10] dt-bindings: opp: Introduce opp-peak-kBps and opp-avg-kBps bindings
From: Georgi Djakov <hidden>
Date: 2020-05-12 12:53:58
Also in:
linux-pm, lkml
Subsystem:
open firmware and flattened device tree bindings, operating performance points (opp), the rest · Maintainers:
Rob Herring, Krzysztof Kozlowski, Conor Dooley, Viresh Kumar, Nishanth Menon, Stephen Boyd, Linus Torvalds
From: Saravana Kannan <redacted> Interconnects often quantify their performance points in terms of bandwidth. So, add opp-peak-kBps (required) and opp-avg-kBps (optional) to allow specifying Bandwidth OPP tables in DT. opp-peak-kBps is a required property that replaces opp-hz for Bandwidth OPP tables. opp-avg-kBps is an optional property that can be used in Bandwidth OPP tables. Signed-off-by: Saravana Kannan <redacted> Reviewed-by: Sibi Sankar <redacted> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Georgi Djakov <redacted> --- v8: * Picked reviewed-by tags. * Changes on wording. Documentation/devicetree/bindings/opp/opp.txt | 17 ++++++++++++++--- .../devicetree/bindings/property-units.txt | 4 ++++ 2 files changed, 18 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 68592271461f..9d16d417e9be 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt@@ -83,9 +83,14 @@ properties. Required properties: - opp-hz: Frequency in Hz, expressed as a 64-bit big-endian integer. This is a - required property for all device nodes but devices like power domains. The - power domain nodes must have another (implementation dependent) property which - uniquely identifies the OPP nodes. + required property for all device nodes, unless another "required" property to + uniquely identify the OPP nodes exists. Devices like power domains must have + another (implementation dependent) property. + +- opp-peak-kBps: Peak bandwidth in kilobytes per second, expressed as an array + of 32-bit big-endian integers. Each element of the array represents the + peak bandwidth value of each interconnect path. The number of elements should + match the number of interconnect paths. Optional properties: - opp-microvolt: voltage in micro Volts.
@@ -132,6 +137,12 @@ Optional properties: - opp-level: A value representing the performance level of the device, expressed as a 32-bit integer. +- opp-avg-kBps: Average bandwidth in kilobytes per second, expressed as an array + of 32-bit big-endian integers. Each element of the array represents the + average bandwidth value of each interconnect path. The number of elements + should match the number of interconnect paths. This property is only + meaningful in OPP tables where opp-peak-kBps is present. + - clock-latency-ns: Specifies the maximum possible transition latency (in nanoseconds) for switching to this OPP from any other OPP.
diff --git a/Documentation/devicetree/bindings/property-units.txt b/Documentation/devicetree/bindings/property-units.txt
index e9b8360b3288..c80a110c1e26 100644
--- a/Documentation/devicetree/bindings/property-units.txt
+++ b/Documentation/devicetree/bindings/property-units.txt@@ -41,3 +41,7 @@ Temperature Pressure ---------------------------------------- -kpascal : kilopascal + +Throughput +---------------------------------------- +-kBps : kilobytes per second