43 lines
1.4 KiB
Plaintext
43 lines
1.4 KiB
Plaintext
MSM device bandwidth device
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devbw is a device that represents a MSM device's BW requirements from its
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master port(s) to a different device's slave port(s) in a MSM SoC. This
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device is typically used to vote for BW requirements from a device's (Eg:
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CPU, GPU) master port(s) to the slave (Eg: DDR) port(s).
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Required properties:
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- compatible: Must be "qcom,devbw"
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- qcom,src-dst-ports: A list of tuples where each tuple consists of a bus
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master port number and a bus slave port number.
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- qcom,bw-tbl: A list of meaningful instantaneous bandwidth values
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(in MB/s) that can be requested from the device
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master port to the slave port. The list of values
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depend on the supported bus/slave frequencies and the
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bus width.
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Optional properties:
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- qcom,active-only: Indicates that the bandwidth votes need to be
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enforced only when the CPU subsystem is active.
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- governor: Initial governor to use for the device.
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Default: "performance"
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- qcom,ab-percent: Indicates a value in percent of instantaneous
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bandwidth which will be used to calculate the
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absolute/average bandwidth.
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Example:
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qcom,cpubw {
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compatible = "qcom,devbw";
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qcom,src-dst-ports = <1 512>, <2 512>;
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qcom,active-only;
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qcom,bw-tbl =
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< 572 /* 75 MHz */ >,
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< 1144 /* 150 MHz */ >,
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< 1525 /* 200 MHz */ >,
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< 2342 /* 307 MHz */ >,
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< 3509 /* 460 MHz */ >,
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< 4684 /* 614 MHz */ >,
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< 6103 /* 800 MHz */ >,
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< 7102 /* 931 MHz */ >;
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};
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