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

On 2/3/26 10:31 AM, Suzuki K Poulose wrote:

On 03/02/2026 09:00, Jie Gan wrote:

quoted

On 2/3/2026 4:50 PM, Konrad Dybcio wrote:

quoted

On 2/3/26 9:08 AM, Jie Gan wrote:

quoted

Document the platforms that fallback to using the qcom,sa8775p-ctcu
compatible for probing.

Signed-off-by: Jie Gan <redacted>
---
  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