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[PATCH 1/3] dt-binding: document QCOM platforms for CTCU device

Jie Gan posted 3 patches 6 days, 12 hours ago
There is a newer version of this series
[PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Jie Gan 6 days, 12 hours ago 
Document the platforms that fallback to using the qcom,sa8775p-ctcu
compatible for probing.

Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
---
 Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
index e002f87361ad..68853db52bef 100644
--- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
+++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
@@ -29,6 +29,10 @@ properties:
     oneOf:
       - items:
           - enum:
+              - qcom,glymur-ctcu
+              - qcom,hamoa-ctcu
+              - qcom,kaanapali-ctcu
+              - qcom,pakala-ctcu
               - qcom,qcs8300-ctcu
           - const: qcom,sa8775p-ctcu
       - enum:

-- 
2.34.1
Re: [PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Konrad Dybcio 6 days, 11 hours ago 
On 2/3/26 9:08 AM, Jie Gan wrote:
> Document the platforms that fallback to using the qcom,sa8775p-ctcu
> compatible for probing.
> 
> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
> ---
>  Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
> index e002f87361ad..68853db52bef 100644
> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
> @@ -29,6 +29,10 @@ properties:
>      oneOf:
>        - items:
>            - enum:
> +              - qcom,glymur-ctcu
> +              - qcom,hamoa-ctcu
> +              - qcom,kaanapali-ctcu
> +              - qcom,pakala-ctcu

Platforms with existing numeric compatibles should continue to use them,
so that the mess is somewhat containable

Konrad
Re: [PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Jie Gan 6 days, 11 hours ago 

On 2/3/2026 4:50 PM, Konrad Dybcio wrote:
> On 2/3/26 9:08 AM, Jie Gan wrote:
>> Document the platforms that fallback to using the qcom,sa8775p-ctcu
>> compatible for probing.
>>
>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>> ---
>>   Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>> index e002f87361ad..68853db52bef 100644
>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>> @@ -29,6 +29,10 @@ properties:
>>       oneOf:
>>         - items:
>>             - enum:
>> +              - qcom,glymur-ctcu
>> +              - qcom,hamoa-ctcu
>> +              - qcom,kaanapali-ctcu
>> +              - qcom,pakala-ctcu
> 
> Platforms with existing numeric compatibles should continue to use them,
> so that the mess is somewhat containable

Sure Konrad. So for Pakala, I will change it back to qcom,sm8750-ctcu

Thanks,
Jie

> 
> Konrad
Re: [PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Suzuki K Poulose 6 days, 10 hours ago 
On 03/02/2026 09:00, Jie Gan wrote:
> 
> 
> On 2/3/2026 4:50 PM, Konrad Dybcio wrote:
>> On 2/3/26 9:08 AM, Jie Gan wrote:
>>> Document the platforms that fallback to using the qcom,sa8775p-ctcu
>>> compatible for probing.
>>>
>>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>>> ---
>>>   Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 
>>> ++++
>>>   1 file changed, 4 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight- 
>>> ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight- 
>>> ctcu.yaml
>>> index e002f87361ad..68853db52bef 100644
>>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>> @@ -29,6 +29,10 @@ properties:
>>>       oneOf:
>>>         - items:
>>>             - enum:
>>> +              - qcom,glymur-ctcu
>>> +              - qcom,hamoa-ctcu
>>> +              - qcom,kaanapali-ctcu
>>> +              - qcom,pakala-ctcu
>>
>> Platforms with existing numeric compatibles should continue to use them,
>> so that the mess is somewhat containable
> 
> Sure Konrad. So for Pakala, I will change it back to qcom,sm8750-ctcu

Why do we need different compatibles for the others ? Are they not all 
compliant to the CTCU programming model ? i.e., sa8775p-ctcu ? or even,
a generic,

qcom,coresight-ctcu

Suzuki



> 
> Thanks,
> Jie
> 
>>
>> Konrad
>
Re: [PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Jie Gan 6 days, 10 hours ago 

On 2/3/2026 5:31 PM, Suzuki K Poulose wrote:
> On 03/02/2026 09:00, Jie Gan wrote:
>>
>>
>> On 2/3/2026 4:50 PM, Konrad Dybcio wrote:
>>> On 2/3/26 9:08 AM, Jie Gan wrote:
>>>> Document the platforms that fallback to using the qcom,sa8775p-ctcu
>>>> compatible for probing.
>>>>
>>>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>>>> ---
>>>>   Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 
>>>> ++++
>>>>   1 file changed, 4 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight- 
>>>> ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight- 
>>>> ctcu.yaml
>>>> index e002f87361ad..68853db52bef 100644
>>>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>> @@ -29,6 +29,10 @@ properties:
>>>>       oneOf:
>>>>         - items:
>>>>             - enum:
>>>> +              - qcom,glymur-ctcu
>>>> +              - qcom,hamoa-ctcu
>>>> +              - qcom,kaanapali-ctcu
>>>> +              - qcom,pakala-ctcu
>>>
>>> Platforms with existing numeric compatibles should continue to use them,
>>> so that the mess is somewhat containable
>>
>> Sure Konrad. So for Pakala, I will change it back to qcom,sm8750-ctcu
> 
> Why do we need different compatibles for the others ? Are they not all 
> compliant to the CTCU programming model ? i.e., sa8775p-ctcu ? or even,
> a generic,
> 
> qcom,coresight-ctcu

Hi Suzuki,

The platforms here have two ETR devices, using same "data" in driver. We 
also have platforms only contain one ETR device and we need create a new 
data for these platforms.

I have proposed previously to have generic compatible for CTCU device 
but I got comment for preferring use platform-specific compatible.

Is that acceptable to use qcom,coresight-ctcu-v1 for TWO ETR devices 
platform and qcom,coresight-ctcu-v2 for ONE ETR device platform?

I think it's better to avoid annoying dt-binding patches for the CTCU 
device.

Thanks,
Jie

> 
> Suzuki
> 
> 
> 
>>
>> Thanks,
>> Jie
>>
>>>
>>> Konrad
>>
>
Re: [PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Konrad Dybcio 6 days, 10 hours ago 
On 2/3/26 10:31 AM, Suzuki K Poulose wrote:
> On 03/02/2026 09:00, Jie Gan wrote:
>>
>>
>> On 2/3/2026 4:50 PM, Konrad Dybcio wrote:
>>> On 2/3/26 9:08 AM, Jie Gan wrote:
>>>> Document the platforms that fallback to using the qcom,sa8775p-ctcu
>>>> compatible for probing.
>>>>
>>>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>>>> ---
>>>>   Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 ++++
>>>>   1 file changed, 4 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight- ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight- ctcu.yaml
>>>> index e002f87361ad..68853db52bef 100644
>>>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>> @@ -29,6 +29,10 @@ properties:
>>>>       oneOf:
>>>>         - items:
>>>>             - enum:
>>>> +              - qcom,glymur-ctcu
>>>> +              - qcom,hamoa-ctcu
>>>> +              - qcom,kaanapali-ctcu
>>>> +              - qcom,pakala-ctcu
>>>
>>> Platforms with existing numeric compatibles should continue to use them,
>>> so that the mess is somewhat containable
>>
>> Sure Konrad. So for Pakala, I will change it back to qcom,sm8750-ctcu
> 
> Why do we need different compatibles for the others ? Are they not all compliant to the CTCU programming model ? i.e., sa8775p-ctcu ? or even,
> a generic,
> 
> qcom,coresight-ctcu

It's a huge anti-pattern with the DT maintainers, since a compatible is
the only way to effectively differentiate different implementations (i.e.
instances on different SoCs) of an IP block

This is important for the case where a DTB is shipped as part of firmware
and can not be replaced - if some quirk needs to be applied retroactively,
we can look for "qcom,glymur-ctcu" without affecting all the 50 other'
users of the effectively-identical IP block

In this case, we're already reducing the impact on the driver, as that
only looks for the single fallback compatible (qcom,sa8775p-ctcu)

Konrad
Re: [PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Suzuki K Poulose 6 days, 10 hours ago 
On 03/02/2026 09:36, Konrad Dybcio wrote:
> On 2/3/26 10:31 AM, Suzuki K Poulose wrote:
>> On 03/02/2026 09:00, Jie Gan wrote:
>>>
>>>
>>> On 2/3/2026 4:50 PM, Konrad Dybcio wrote:
>>>> On 2/3/26 9:08 AM, Jie Gan wrote:
>>>>> Document the platforms that fallback to using the qcom,sa8775p-ctcu
>>>>> compatible for probing.
>>>>>
>>>>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>>>>> ---
>>>>>    Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 ++++
>>>>>    1 file changed, 4 insertions(+)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight- ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight- ctcu.yaml
>>>>> index e002f87361ad..68853db52bef 100644
>>>>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>>> @@ -29,6 +29,10 @@ properties:
>>>>>        oneOf:
>>>>>          - items:
>>>>>              - enum:
>>>>> +              - qcom,glymur-ctcu
>>>>> +              - qcom,hamoa-ctcu
>>>>> +              - qcom,kaanapali-ctcu
>>>>> +              - qcom,pakala-ctcu
>>>>
>>>> Platforms with existing numeric compatibles should continue to use them,
>>>> so that the mess is somewhat containable
>>>
>>> Sure Konrad. So for Pakala, I will change it back to qcom,sm8750-ctcu
>>
>> Why do we need different compatibles for the others ? Are they not all compliant to the CTCU programming model ? i.e., sa8775p-ctcu ? or even,
>> a generic,
>>
>> qcom,coresight-ctcu
> 
> It's a huge anti-pattern with the DT maintainers, since a compatible is
> the only way to effectively differentiate different implementations (i.e.
> instances on different SoCs) of an IP block

Do you mean, same IP block integrated to different SoC ? Or are they
different implementations altogether ? Why are these not applicable for
other components ? (e.g., Tnoc, I-Tnoc, TPDA, TPDM etc ?)

> 
> This is important for the case where a DTB is shipped as part of firmware
> and can not be replaced - if some quirk needs to be applied retroactively,
> we can look for "qcom,glymur-ctcu" without affecting all the 50 other'
> users of the effectively-identical IP block

Fair enough, thank for the explanation.

Kind regards
Suzuki

> 
> In this case, we're already reducing the impact on the driver, as that
> only looks for the single fallback compatible (qcom,sa8775p-ctcu)
> 
> Konrad
Re: [PATCH 1/3] dt-binding: document QCOM platforms for CTCU device
Posted by Konrad Dybcio 6 days, 9 hours ago 
On 2/3/26 10:44 AM, Suzuki K Poulose wrote:
> On 03/02/2026 09:36, Konrad Dybcio wrote:
>> On 2/3/26 10:31 AM, Suzuki K Poulose wrote:
>>> On 03/02/2026 09:00, Jie Gan wrote:
>>>>
>>>>
>>>> On 2/3/2026 4:50 PM, Konrad Dybcio wrote:
>>>>> On 2/3/26 9:08 AM, Jie Gan wrote:
>>>>>> Document the platforms that fallback to using the qcom,sa8775p-ctcu
>>>>>> compatible for probing.
>>>>>>
>>>>>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>>>>>> ---
>>>>>>    Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 4 ++++
>>>>>>    1 file changed, 4 insertions(+)
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight- ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight- ctcu.yaml
>>>>>> index e002f87361ad..68853db52bef 100644
>>>>>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>>>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>>>>>> @@ -29,6 +29,10 @@ properties:
>>>>>>        oneOf:
>>>>>>          - items:
>>>>>>              - enum:
>>>>>> +              - qcom,glymur-ctcu
>>>>>> +              - qcom,hamoa-ctcu
>>>>>> +              - qcom,kaanapali-ctcu
>>>>>> +              - qcom,pakala-ctcu
>>>>>
>>>>> Platforms with existing numeric compatibles should continue to use them,
>>>>> so that the mess is somewhat containable
>>>>
>>>> Sure Konrad. So for Pakala, I will change it back to qcom,sm8750-ctcu
>>>
>>> Why do we need different compatibles for the others ? Are they not all compliant to the CTCU programming model ? i.e., sa8775p-ctcu ? or even,
>>> a generic,
>>>
>>> qcom,coresight-ctcu
>>
>> It's a huge anti-pattern with the DT maintainers, since a compatible is
>> the only way to effectively differentiate different implementations (i.e.
>> instances on different SoCs) of an IP block
> 
> Do you mean, same IP block integrated to different SoC ? Or are they
> different implementations altogether ? Why are these not applicable for
> other components ? (e.g., Tnoc, I-Tnoc, TPDA, TPDM etc ?)

The former.

I think coresight bindings are fully generic, since they have been in
place for about as long as the arm64 port, which precedes actual bindings
validation (yaml dt-bindings) and in those times the requirements were way
more lax

Konrad

>> This is important for the case where a DTB is shipped as part of firmware
>> and can not be replaced - if some quirk needs to be applied retroactively,
>> we can look for "qcom,glymur-ctcu" without affecting all the 50 other'
>> users of the effectively-identical IP block
> 
> Fair enough, thank for the explanation.
> 
> Kind regards
> Suzuki
> 
>>
>> In this case, we're already reducing the impact on the driver, as that
>> only looks for the single fallback compatible (qcom,sa8775p-ctcu)
>>
>> Konrad
>

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