Re: [PATCH v4 4/5] arm64: dts: qcom: sm8250: Add JPEG encoder node

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Missing interconnect bandwidth configuration (`opp-peak-kBps`) in `jpeg_opp_table`
--

commit 616b7352b84f0f021a4d35b811588d48e0fe74d6
Author: Atanas Filipov <atanas.filipov@oss.qualcomm.com>

arm64: dts: qcom: sm8250: Add JPEG encoder node
    
Adds the JPEG encoder hardware node to the SM8250 device tree so the
qcom-jpeg V4L2 encoder driver can bind and operate on this platform.

> diff --git a/arch/arm64/boot/dts/qcom/sm8250.dtsi b/arch/arm64/boot/dts/qcom/sm8250.dtsi
> index 7076720413ab2..a089b706f60c6 100644
> --- a/arch/arm64/boot/dts/qcom/sm8250.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8250.dtsi
[ ... ]
> @@ -4649,6 +4654,82 @@ port@5 {
>  					reg = <5>;
>  				};
>  			};
> +
> +			jpeg-encoder@ac53000 {
> +				compatible = "qcom,sm8250-jenc";
[ ... ]
> +				interconnects = <&gem_noc MASTER_AMPSS_M0
> +						 QCOM_ICC_TAG_ACTIVE_ONLY
> +						 &config_noc SLAVE_CAMERA_CFG
> +						 QCOM_ICC_TAG_ACTIVE_ONLY>,
> +						<&mmss_noc MASTER_CAMNOC_HF
> +						 QCOM_ICC_TAG_ALWAYS
> +						 &mc_virt SLAVE_EBI_CH0
> +						 QCOM_ICC_TAG_ALWAYS>,
> +						<&mmss_noc MASTER_CAMNOC_SF
> +						 QCOM_ICC_TAG_ALWAYS
> +						 &mc_virt SLAVE_EBI_CH0
> +						 QCOM_ICC_TAG_ALWAYS>;
> +				interconnect-names = "cpu-cfg",
> +						     "hf-mnoc",
> +						     "sf-mnoc";
> +
> +				iommus = <&apps_smmu 0x2040 0x400>;
> +
> +				operating-points-v2 = <&jpeg_opp_table>;
> +
> +				jpeg_opp_table: opp-table {
> +					compatible = "operating-points-v2";
> +
> +					opp-100000000 {
> +						opp-hz = /bits/ 64 <400000000>,
> +							 /bits/ 64 <100000000>;
> +						required-opps = <&rpmhpd_opp_min_svs>;
> +					};

[Severity: High]
Does this missing opp-peak-kBps configuration cause interconnect bandwidth to
default to 0?

Since the interconnects are defined on the jpeg-encoder node, when the driver
dynamically sets an operating point via dev_pm_opp_set_opp() during runtime,
the OPP core will iterate over these interconnect paths and call icc_set_bw().

Without opp-peak-kBps, won't this vote for 0 bandwidth on the hf-mnoc, sf-mnoc,
and cpu-cfg interconnects? This could effectively disable or clock-gate the
memory buses, triggering NoC stalls, SMMU faults, or fatal bus errors when the
encoder subsequently attempts DMA memory access.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260706071113.383215-1-atanas.filipov@oss.qualcomm.com?part=4