Re: [PATCH] arm64: dts: qcom: sm8750: mark the ADSP fastrpc node as non-secure domain

[Konrad Dybcio]

On 11/7/26 4:26 AM, Qianhui Xu wrote:
> On SM8750 the ADSP fastrpc instance used by the sensor core (and by the
> other non-secure ADSP users) is the one the firmware exposes as
> non-secure; the CDSP fastrpc node already carries
> "qcom,non-secure-domain", the ADSP one does not.  With the fastrpc driver
> keying the secure/non-secure split off that property, the ADSP only
> instantiates /dev/fastrpc-adsp-secure and userspace never gets
> /dev/fastrpc-adsp, so libssc/hexagonrpcd cannot attach to the sensor PD
> (qrtr service 400) and iio-sensor-proxy reports no sensors at all.

Hm, this is a nuanced case - adding +Ekansh, +Dmitry and +Srini

> Observed on the Lenovo Legion Tab Y700 Gen4 (TB322FC), which is SM8750
> based: without this property /dev/fastrpc-adsp never appears and
> iio-sensor-proxy exposes neither accelerometer, ambient light nor
> proximity; with it, qrtr shows the "Snapdragon Sensor Core service"
> (id 400) and all three sensor types report as available.  The change is
> one property on one node, matching what the CDSP node already does.
> 
> Tested with `make CHECK_DTBS=y qcom/sm8750-mtp.dtb` (no new warnings; the
> single avoid_unnecessary_addr_size warning on dsi@ae96000 is present
> before and after).
> 
> *** AI-assistance disclosure ***
> This patch and its commit message were prepared with the help of an LLM
> coding assistant.  The author reviewed the change line by line, ran the
> checks quoted above on his own hardware and takes full responsibility
> for the content.

Please keep that under the --- line so it doesn't end up in the commit
log.

Konrad

> 
> Signed-off-by: Qianhui Xu <xiaqinghuan@xxxxxxxxxxxxxxxx>
> ---
>  arch/arm64/boot/dts/qcom/sm8750.dtsi | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sm8750.dtsi b/arch/arm64/boot/dts/qcom/sm8750.dtsi
> index cf947acc57..9302481b11 100644
> --- a/arch/arm64/boot/dts/qcom/sm8750.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8750.dtsi
> @@ -2571,6 +2571,7 @@ fastrpc {
>  					compatible = "qcom,fastrpc";
>  					qcom,glink-channels = "fastrpcglink-apps-dsp";
>  					label = "adsp";
> +					qcom,non-secure-domain;
>  					memory-region = <&adsp_rpc_remote_heap_mem>;
>  					qcom,vmids = <QCOM_SCM_VMID_LPASS
>  						      QCOM_SCM_VMID_ADSP_HEAP>;