diff mbox series

[v2,2/3] dt-bindings: opp: Add v2-qcom-adreno vendor bindings

Message ID 20241021-gpu-acd-v2-2-9c25a62803bc@quicinc.com
State New
Headers show
Series Support for GPU ACD feature on Adreno X1-85 | expand

Commit Message

Akhil P Oommen Oct. 21, 2024, 11:53 a.m. UTC
Add a new schema which extends opp-v2 to support a new vendor specific
property required for Adreno GPUs found in Qualcomm's SoCs. The new
property called "qcom,opp-acd-level" carries a u32 value recommended
for each opp needs to be shared to GMU during runtime.

Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
---
 .../bindings/opp/opp-v2-qcom-adreno.yaml           | 96 ++++++++++++++++++++++
 1 file changed, 96 insertions(+)

Comments

Akhil P Oommen Nov. 1, 2024, 4:24 p.m. UTC | #1
On 10/25/2024 11:58 AM, Dmitry Baryshkov wrote:
> On Thu, Oct 24, 2024 at 12:56:58AM +0530, Akhil P Oommen wrote:
>> On 10/22/2024 11:19 AM, Krzysztof Kozlowski wrote:
>>> On Mon, Oct 21, 2024 at 05:23:43PM +0530, Akhil P Oommen wrote:
>>>> Add a new schema which extends opp-v2 to support a new vendor specific
>>>> property required for Adreno GPUs found in Qualcomm's SoCs. The new
>>>> property called "qcom,opp-acd-level" carries a u32 value recommended
>>>> for each opp needs to be shared to GMU during runtime.
>>>>
>>>> Cc: Rob Clark <robdclark@gmail.com>
>>>> Signed-off-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
>>>> ---
>>>>  .../bindings/opp/opp-v2-qcom-adreno.yaml           | 96 ++++++++++++++++++++++
>>>>  1 file changed, 96 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/opp/opp-v2-qcom-adreno.yaml b/Documentation/devicetree/bindings/opp/opp-v2-qcom-adreno.yaml
>>>> new file mode 100644
>>>> index 000000000000..6d50c0405ef8
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/opp/opp-v2-qcom-adreno.yaml
>>>> @@ -0,0 +1,96 @@
>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>>> +%YAML 1.2
>>>> +---
>>>> +$id: http://devicetree.org/schemas/opp/opp-v2-qcom-adreno.yaml#
>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>> +
>>>> +title: Qualcomm Adreno compatible OPP supply
>>>> +
>>>> +description:
>>>> +  Adreno GPUs present in Qualcomm's Snapdragon chipsets uses an OPP specific
>>>> +  ACD related information tailored for the specific chipset. This binding
>>>> +  provides the information needed to describe such a hardware value.
>>>> +
>>>> +maintainers:
>>>> +  - Rob Clark <robdclark@gmail.com>
>>>> +
>>>> +allOf:
>>>> +  - $ref: opp-v2-base.yaml#
>>>> +
>>>> +properties:
>>>> +  compatible:
>>>> +    items:
>>>> +      - const: operating-points-v2-adreno
>>>> +      - const: operating-points-v2
>>>> +
>>>> +patternProperties:
>>>> +  '^opp-?[0-9]+$':
>>>
>>> '-' should not be optional. opp1 is not expected name.
>>
>> Agree. Will change this to '^opp-[0-9]+$'
>>
>>>
>>>> +    type: object
>>>> +    additionalProperties: false
>>>> +
>>>> +    properties:
>>>> +      opp-hz: true
>>>> +
>>>> +      opp-level: true
>>>> +
>>>> +      opp-peak-kBps: true
>>>> +
>>>> +      opp-supported-hw: true
>>>> +
>>>> +      qcom,opp-acd-level:
>>>> +        description: |
>>>> +          A positive value representing the ACD (Adaptive Clock Distribution,
>>>> +          a fancy name for clk throttling during voltage droop) level associated
>>>> +          with this OPP node. This value is shared to a co-processor inside GPU
>>>> +          (called Graphics Management Unit a.k.a GMU) during wake up. It may not
>>>> +          be present for some OPPs and GMU will disable ACD while transitioning
>>>> +          to that OPP. This value encodes a voltage threshold and few other knobs
>>>> +          which are identified by characterization of the SoC. So, it doesn't have
>>>> +          any unit.
>>>
>>> Thanks for explanation and other updates. I am still not happy with this
>>> property. I do not see reason why DT should encode magic values in a
>>> quite generic piece of code. This creates poor ABI, difficult to
>>> maintain or understand.
>>>
>>
>> Configuring GPU ACD block with its respective value is a requirement for each OPP.
>> So OPP node seems like the natural place for this data.
>>
>> If it helps to resolve your concerns, I can elaborate the documentation with
>> details on the GMU HFI interface where this value should be passed on to the
>> hardware. Also replace "few other knobs" with "Delay cycles & Calibration margin"
>> in the above doc.
> 
> Usually the preference for DT is to specify data in a sensible way
> rather than just the values being programmed to the register. Is it
> possible to implement this approach for ACD values?

I am still checking about this. Will get back.

-Akhil

> 
>>  
>>>
>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/opp/opp-v2-qcom-adreno.yaml b/Documentation/devicetree/bindings/opp/opp-v2-qcom-adreno.yaml
new file mode 100644
index 000000000000..6d50c0405ef8
--- /dev/null
+++ b/Documentation/devicetree/bindings/opp/opp-v2-qcom-adreno.yaml
@@ -0,0 +1,96 @@ 
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/opp/opp-v2-qcom-adreno.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm Adreno compatible OPP supply
+
+description:
+  Adreno GPUs present in Qualcomm's Snapdragon chipsets uses an OPP specific
+  ACD related information tailored for the specific chipset. This binding
+  provides the information needed to describe such a hardware value.
+
+maintainers:
+  - Rob Clark <robdclark@gmail.com>
+
+allOf:
+  - $ref: opp-v2-base.yaml#
+
+properties:
+  compatible:
+    items:
+      - const: operating-points-v2-adreno
+      - const: operating-points-v2
+
+patternProperties:
+  '^opp-?[0-9]+$':
+    type: object
+    additionalProperties: false
+
+    properties:
+      opp-hz: true
+
+      opp-level: true
+
+      opp-peak-kBps: true
+
+      opp-supported-hw: true
+
+      qcom,opp-acd-level:
+        description: |
+          A positive value representing the ACD (Adaptive Clock Distribution,
+          a fancy name for clk throttling during voltage droop) level associated
+          with this OPP node. This value is shared to a co-processor inside GPU
+          (called Graphics Management Unit a.k.a GMU) during wake up. It may not
+          be present for some OPPs and GMU will disable ACD while transitioning
+          to that OPP. This value encodes a voltage threshold and few other knobs
+          which are identified by characterization of the SoC. So, it doesn't have
+          any unit.
+        $ref: /schemas/types.yaml#/definitions/uint32
+
+    required:
+      - opp-hz
+      - opp-level
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/power/qcom-rpmpd.h>
+
+    gpu_opp_table: opp-table {
+        compatible = "operating-points-v2-adreno", "operating-points-v2";
+
+        opp-687000000 {
+                opp-hz = /bits/ 64 <687000000>;
+                opp-level = <RPMH_REGULATOR_LEVEL_SVS_L1>;
+                opp-peak-kBps = <8171875>;
+                qcom,opp-acd-level = <0x882e5ffd>;
+        };
+
+        opp-550000000 {
+                opp-hz = /bits/ 64 <550000000>;
+                opp-level = <RPMH_REGULATOR_LEVEL_SVS>;
+                opp-peak-kBps = <6074219>;
+                qcom,opp-acd-level = <0xc0285ffd>;
+        };
+
+        opp-390000000 {
+                opp-hz = /bits/ 64 <390000000>;
+                opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
+                opp-peak-kBps = <3000000>;
+                qcom,opp-acd-level = <0xc0285ffd>;
+        };
+
+        opp-300000000 {
+                opp-hz = /bits/ 64 <300000000>;
+                opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS_D1>;
+                opp-peak-kBps = <2136719>;
+                /* Intentionally left out qcom,opp-acd-level property here */
+        };
+
+    };