Re: [PATCH v6 0/5] Fix traceNoC probe issue on multiple QCOM platforms

[Suzuki K Poulose]

On 09/11/2026 01:25, Jie Gan wrote:
> On 7/10/2026 10:38 AM, Jie Gan wrote:
> > The CoreSight TNOC (Trace Network-On-Chip) binding so far only allowed 
> > the
> > two-string AMBA form "qcom,coresight-tnoc", "arm,primecell". That form
> > forces the device onto the AMBA bus, where the driver must read the
> > peripheral ID from the device registers during probe. On several QCOM
> > platforms this AMBA peripheral-ID probing fails, so the traceNoC device
> > never probes and its trace path is unavailable.
> >
> > This series drops the "arm,primecell" entry and turns "qcom,coresight- 
> > tnoc"
> > into a standalone platform compatible. Without "arm,primecell" the device
> > is created on the platform bus and probes through the platform driver by
> > compatible string, bypassing the AMBA peripheral-ID read while 
> > remaining a
> > fully functional Aggregator TNOC that allocates a system trace ID (ATID).
> >
> > The series is organized as: binding first, then the driver support for 
> > the
> > platform-bus compatible, followed by the per-platform DT fixes that 
> > switch
> > the affected nodes over to it.
> >
> > - Patch 1 (dt-bindings) drops "arm,primecell" and makes
> > "qcom,coresight-tnoc" a single standalone compatible, and updates the
> > example node accordingly.
> > - Patch 2 (driver) adds "qcom,coresight-tnoc" to the platform driver's
> > match table and renames the itnoc-specific names to generic tnoc names,
> > since the platform driver now serves both the Interconnect and Aggregator
> > TNOC. It also restricts the ATID-unsupported handling to
> > "qcom,coresight-itnoc" only, so the Aggregator TNOC on the platform 
> > bus is
> > no longer wrongly covered and correctly allocates a trace ID.
> > - Patches 3-4 (kaanapali, sm8750) drop the "arm,primecell" entry on the
> > traceNoC nodes and use the standalone "qcom,coresight-tnoc" compatible,
> > fixing the probe failure on those platforms.
> > - Patch 5 (glymur) switches the node from "qcom,coresight-itnoc" to
> > "qcom,coresight-tnoc". This node is actually an Aggregator TNOC (its
> > tn_ag_* endpoints show aggregation), so it should expose a system trace
> > ID rather than being treated as an Interconnect TNOC.
>
> Gentle ping.

Apologies for missing this. Please could you resend it based on v7.4-rc,
as this doesn't apply cleanly on coresight/next

Cheers
Suzuki