| Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) |
| 2 | %YAML 1.2 |
| 3 | --- |
| 4 | $id: http://devicetree.org/schemas/soc/qcom/qcom,rpm-master-stats.yaml# |
| 5 | $schema: http://devicetree.org/meta-schemas/core.yaml# |
| 6 | |
| 7 | title: Qualcomm Technologies, Inc. (QTI) RPM Master Stats |
| 8 | |
| 9 | maintainers: |
| 10 | - Konrad Dybcio <konrad.dybcio@linaro.org> |
| 11 | |
| 12 | description: | |
| 13 | The Qualcomm RPM (Resource Power Manager) architecture includes a concept |
| 14 | of "RPM Masters". They can be thought of as "the local gang leaders", usually |
| 15 | spanning a single subsystem (e.g. APSS, ADSP, CDSP). All of the RPM decisions |
| 16 | (particularly around entering hardware-driven low power modes: XO shutdown |
| 17 | and total system-wide power collapse) are first made at Master-level, and |
| 18 | only then aggregated for the entire system. |
| 19 | |
| 20 | The Master Stats provide a few useful bits that can be used to assess whether |
| 21 | our device has entered the desired low-power mode, how long it took to do so, |
| 22 | the duration of that residence, how long it took to come back online, |
| 23 | how many times a given sleep state was entered and which cores are actively |
| 24 | voting for staying awake. |
| 25 | |
| 26 | This scheme has been used on various SoCs in the 2013-2023 era, with some |
| 27 | newer or higher-end designs providing this information through an SMEM query. |
| 28 | |
| 29 | properties: |
| 30 | compatible: |
| 31 | const: qcom,rpm-master-stats |
| 32 | |
| 33 | qcom,rpm-msg-ram: |
| 34 | $ref: /schemas/types.yaml#/definitions/phandle-array |
| 35 | description: Phandle to an RPM MSG RAM slice containing the master stats |
| 36 | minItems: 1 |
| 37 | maxItems: 5 |
| 38 | |
| 39 | qcom,master-names: |
| 40 | $ref: /schemas/types.yaml#/definitions/string-array |
| 41 | description: |
| 42 | The name of the RPM Master which owns the MSG RAM slice where this |
| 43 | instance of Master Stats resides |
| 44 | minItems: 1 |
| 45 | maxItems: 5 |
| 46 | |
| 47 | required: |
| 48 | - compatible |
| 49 | - qcom,rpm-msg-ram |
| 50 | - qcom,master-names |
| 51 | |
| 52 | additionalProperties: false |
| 53 | |
| 54 | examples: |
| 55 | - | |
| 56 | stats { |
| 57 | compatible = "qcom,rpm-master-stats"; |
| 58 | qcom,rpm-msg-ram = <&apss_master_stats>, |
| 59 | <&mpss_master_stats>, |
| 60 | <&adsp_master_stats>, |
| 61 | <&cdsp_master_stats>, |
| 62 | <&tz_master_stats>; |
| 63 | qcom,master-names = "APSS", |
| 64 | "MPSS", |
| 65 | "ADSP", |
| 66 | "CDSP", |
| 67 | "TZ"; |
| 68 | }; |
| 69 | ... |