On 11/14/2025 5:30 PM, Akhil P Oommen wrote:
> On 11/10/2025 1:21 PM, Krzysztof Kozlowski wrote:
>> On Fri, Nov 07, 2025 at 02:20:08AM +0530, Akhil P Oommen wrote:
>>> From: Jie Zhang <[email protected]>
>>>
>>> RGMU a.k.a Reduced Graphics Management Unit is a small state machine
>>> with the sole purpose of providing IFPC (Inter Frame Power Collapse)
>>> support. Compared to GMU, it doesn't manage GPU clock, voltage
>>> scaling, bw voting or any other functionalities. All it does is detect
>>> an idle GPU and toggle the GDSC switch. As it doesn't access DDR space,
>>> it doesn't require iommu.
>>>
>>> So far, only Adreno 612 GPU has an RGMU core. Document RGMU in the GMU's
>>> schema.
>>>
>>> Signed-off-by: Jie Zhang <[email protected]>
>>> Signed-off-by: Akhil P Oommen <[email protected]>
>>> ---
>>> .../devicetree/bindings/display/msm/rgmu.yaml | 131
>>> +++++++++++++++++++++
>>> MAINTAINERS | 1 +
>>> 2 files changed, 132 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/display/msm/rgmu.yaml
>>> b/Documentation/devicetree/bindings/display/msm/rgmu.yaml
>>> new file mode 100644
>>> index 000000000000..7621556477d0
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/display/msm/rgmu.yaml
>>
>> Filename matching compatible, so qcom,adreno-rgmu.yaml
>>
>>
>>> @@ -0,0 +1,131 @@
>>> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
>>> +# Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
>>> +%YAML 1.2
>>> +---
>>> +
>>> +$id: http://devicetree.org/schemas/display/msm/rgmu.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: RGMU attached to certain Adreno GPUs
>>> +
>>> +maintainers:
>>> + - Rob Clark <[email protected]>
>>> +
>>> +description: |
>>
>> Do not need '|' unless you need to preserve formatting.
>>
>>> + RGMU (Reduced Graphics Management Unit) IP is present in some GPUs that
>>> + belong to Adreno A6xx family. It is a small state machine that helps to
>>> + toggle the GX GDSC (connected to CX rail) to implement IFPC feature and
>>> save
>>> + power.
>>> +
>>> +properties:
>>> + compatible:
>>> + items:
>>> + - const: qcom,adreno-rgmu-612.0
>>> + - const: qcom,adreno-rgmu
>>> +
>>> + reg:
>>> + items:
>>> + - description: Core RGMU registers
>>> +
>>> + reg-names:
>>> + items:
>>> + - const: gmu
>>
>> Drop reg-names, useless for one entry with same name as the block name.
>
> Just to confirm, drop only reg-names, but keep 'reg'?
Wait. We should keep 'reg'.
If we remove 'reg-names' here, we cannot use reg-names in DT too because
we are setting additionalProperties to False, right?
-Akhil.
>
> -Akhil
>
>>
>>> +
>>> + clocks:
>>> + items:
>>> + - description: GMU clock
>>> + - description: GPU CX clock
>>> + - description: GPU AXI clock
>>> + - description: GPU MEMNOC clock
>>> + - description: GPU SMMU vote clock
>>> +
>>> + clock-names:
>>> + items:
>>> + - const: gmu
>>> + - const: cxo
>>> + - const: axi
>>> + - const: memnoc
>>> + - const: smmu_vote
>>> +
>>> + power-domains:
>>> + items:
>>> + - description: CX GDSC power domain
>>> + - description: GX GDSC power domain
>>> +
>>> + power-domain-names:
>>> + items:
>>> + - const: cx
>>> + - const: gx
>>> +
>>> + interrupts:
>>> + items:
>>> + - description: GMU OOB interrupt
>>> + - description: GMU interrupt
>>> +
>>> + interrupt-names:
>>> + items:
>>> + - const: oob
>>> + - const: gmu
>>> +
>>> + operating-points-v2: true
>>> + opp-table:
>>> + type: object
>>> +
>>> +required:
>>
>> compatible
>>
>>> + - reg
>>> + - reg-names
>>> + - clocks
>>> + - clock-names
>>> + - power-domains
>>> + - power-domain-names
>>> + - interrupts
>>> + - interrupt-names
>>
>> Keep the same order as in properties.
>>
>>> + - operating-points-v2
>>> +
>>> +additionalProperties: false
>>> +
>>> +examples:
>>> + - |
>>> + #include <dt-bindings/clock/qcom,qcs615-gpucc.h>
>>> + #include <dt-bindings/clock/qcom,qcs615-gcc.h>
>>> + #include <dt-bindings/interrupt-controller/arm-gic.h>
>>> + #include <dt-bindings/power/qcom,rpmhpd.h>
>>> +
>>> + rgmu: rgmu@506a000 {
>>
>> Drop label.
>>
>> Node names should be generic. See also an explanation and list of
>> examples (not exhaustive) in DT specification:
>> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
>> If you cannot find a name matching your device, please check in kernel
>> sources for similar cases or you can grow the spec (via pull request to
>> DT spec repo).
>>
>> Best regards,
>> Krzysztof
>>
>
