[PATCH v4 0/3] coresight: add static TPDM support

Jie Gan jie.gan at oss.qualcomm.com
Wed Nov 5 21:20:13 PST 2025



On 10/28/2025 6:11 PM, Jie Gan wrote:
> The static TPDM function as a dummy source, however, it is essential
> to enable the port connected to the TPDA and configure the element size.
> Without this, the TPDA cannot correctly receive trace data from the
> static TPDM. Since the static TPDM does not require MMIO mapping to
> access its registers, a clock controller is not mandatory for its
> operation.
> 
> Meanwhile, a function has been introduced to determine whether the
> current csdev is a static TPDM. This check enables the TPDA device
> to correctly read the element size and activate its port accordingly.
> Otherwise the TPDA cannot receive the trace data from the TPDM device.
> 

Gentle reminder.

> Changes in V4:
> 1. decouple from tpda driver code.
> 2. Introduce a new solution to identify static TPDM.
> Link to V3 - https://lore.kernel.org/all/20251013-add-static-tpdm-support-v3-0-a720b73e83db@oss.qualcomm.com/
> 
> Changes in V3:
> 1. rebased on next-20251010
> Link to V2 - https://lore.kernel.org/all/20250911-add_static_tpdm_support-v2-0-608559d36f74@oss.qualcomm.com/
> 
> Changes in V2:
> 1. Remove the dependency.
> 2. Collect tags from Rob and Konard for patchset 1 and patchset 3.
> Link to V1 - https://lore.kernel.org/all/20250822103008.1029-1-jie.gan@oss.qualcomm.com/
> 
> Signed-off-by: Jie Gan <jie.gan at oss.qualcomm.com>
> ---
> Jie Gan (3):
>        dt-bindings: arm: document the static TPDM compatible
>        coresight: tpdm: add static tpdm support
>        arm64: dts: qcom: lemans: enable static TPDM
> 
>   .../bindings/arm/qcom,coresight-tpdm.yaml          |  23 ++-
>   arch/arm64/boot/dts/qcom/lemans.dtsi               | 105 +++++++++++++
>   drivers/hwtracing/coresight/coresight-tpda.c       |   7 -
>   drivers/hwtracing/coresight/coresight-tpdm.c       | 174 +++++++++++++++++----
>   drivers/hwtracing/coresight/coresight-tpdm.h       |  12 ++
>   5 files changed, 279 insertions(+), 42 deletions(-)
> ---
> base-commit: f7d2388eeec24966fc4d5cf32d706f0514f29ac5
> change-id: 20251028-add_static_tpdm_support-1f62477857e2
> 
> Best regards,




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