From: Saravana Kannan <saravanak@xxxxxxxxxx> 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 <saravanak@xxxxxxxxxx> Signed-off-by: Georgi Djakov <georgi.djakov@xxxxxxxxxx> --- v7: * I have dropped Rob's Reviewed-by, because of the minor change below: * In order to store the bandwidth values for multiple paths, the opp-peak-kBps and opp-avg-kBps are now defined as arrays of integers, instead of just integers. * Improved wording (Viresh) v6: https://lore.kernel.org/r/20191207002424.201796-2-saravanak@xxxxxxxxxx Documentation/devicetree/bindings/opp/opp.txt | 20 ++++++++++++++++--- .../devicetree/bindings/property-units.txt | 4 ++++ 2 files changed, 21 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt index 68592271461f..a8a6a3bfcfcb 100644 --- a/Documentation/devicetree/bindings/opp/opp.txt +++ b/Documentation/devicetree/bindings/opp/opp.txt @@ -83,9 +83,17 @@ 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 except for devices like power domains + or bandwidth opp tables. The devices which don't have this property must have + another (implementation dependent) property which uniquely identifies the OPP + nodes. + + +- 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. This is a required property for + bandwidth OPP tables. Optional properties: - opp-microvolt: voltage in micro Volts. @@ -132,6 +140,12 @@ 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
