Re: [PATCH v6 3/5] arm64: dts: qcom: kaanapali: bind traceNoC on the platform bus

[Konrad Dybcio]

On 7/10/26 4:39 AM, Jie Gan wrote:
> The traceNoC node used the "qcom,coresight-tnoc", "arm,primecell"
> compatible, which places the device on the AMBA bus. To bind an AMBA
> device, the bus reads the peripheral and component ID registers (PID/CID)
> at the top of the device's register block and matches them against the
> primecell ID. The traceNoC exposes the CID registers, but the Component ID
> value returned by the hardware is 0x00000000 instead of a valid AMBA
> Component ID, so the match never succeeds, the AMBA probe fails, and the
> device is left stuck in deferred probe indefinitely.
> 
> Drop the "arm,primecell" entry and use the standalone "qcom,coresight-tnoc"
> compatible, which binds via the platform driver by compatible string and
> does not rely on the component ID register at all. This lets the device
> probe on hardware that does not return a valid CID, while remaining an
> Aggregator TNOC that retains ATID functionality.
> 
> Fixes: f73959d86c15 ("arm64: dts: qcom: kaanapali: add coresight nodes")
> Signed-off-by: Jie Gan <jie.gan@xxxxxxxxxxxxxxxx>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>

Konrad