Re: [PATCH V2 1/3] arm64: dts: qcom: monaco: Move eMMC CQE support from SoC to board DT

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] Incomplete genericization of `sdhc_1` leaves conflicting eMMC-specific properties in the SoC DT, breaking SD card compatibility.
- [Medium] Removing the `supports-cqe` property from the SoC-level `monaco.dtsi` without explicitly adding it back to all eMMC-based boards causes a silent performance regression by disabling Command Queue Engine (CQE) support.
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commit 05fd7920ab031fea94cd493a589a30892353cf08
Author: Monish Chunara <monish.chunara@oss.qualcomm.com>

arm64: dts: qcom: monaco: Move eMMC CQE support from SoC to board DT

This commit removes the supports-cqe property from the generic Monaco SoC
device tree and moves it to the qcs8300-ride board device tree. The stated
goal is to allow SD card compatibility in the base SoC definition, since the
Command Queue Engine conflicts with SD card operation.

> diff --git a/arch/arm64/boot/dts/qcom/monaco.dtsi b/arch/arm64/boot/dts/qcom/monaco.dtsi
> index 7b1d57460f1e6..e5f316897706b 100644
> --- a/arch/arm64/boot/dts/qcom/monaco.dtsi
> +++ b/arch/arm64/boot/dts/qcom/monaco.dtsi
> @@ -4828,7 +4828,6 @@ &mc_virt SLAVE_EBI1 QCOM_ICC_TAG_ALWAYS>,
>  			qcom,dll-config = <0x000f64ee>;
>  			qcom,ddr-config = <0x80040868>;
>  			bus-width = <8>;
> -			supports-cqe;

[Severity: Medium]
Removing supports-cqe from the SoC DT without adding it back to all
eMMC-based boards appears to cause a performance regression by disabling the
Command Queue Engine for those boards.

For example, arch/arm64/boot/dts/qcom/monaco-monza-som.dtsi and
arch/arm64/boot/dts/qcom/monaco-evk.dts both configure sdhc_1 as an eMMC
device (using no-sd and non-removable). Since they rely on the SoC DT for
the supports-cqe property, won't omitting it from this patch silently degrade
their performance?

[Severity: High]
The commit message states the goal is to ensure the SoC definition remains
generic for SD card compatibility by removing supports-cqe. However, does
leaving the other eMMC-specific properties in the SoC DT defeat this purpose?

Properties like bus-width = <8>, mmc-hs400-1_8v, mmc-hs400-enhanced-strobe,
qcom,dll-config, and qcom,ddr-config remain in the base monaco.dtsi. Since
device tree overlays do not automatically delete base boolean properties or
override tuning parameters unless explicitly redefined, won't these
incorrectly inherit to SD card configurations and cause the MMC core to
misconfigure the interface?

Should these properties be moved to the eMMC-specific board files as well?

>  			dma-coherent;
>  
>  			mmc-ddr-1_8v;
> diff --git a/arch/arm64/boot/dts/qcom/qcs8300-ride.dts b/arch/arm64/boot/dts/qcom/qcs8300-ride.dts
> index e9a8553a8d821..3090eba0317ac 100644
> --- a/arch/arm64/boot/dts/qcom/qcs8300-ride.dts
> +++ b/arch/arm64/boot/dts/qcom/qcs8300-ride.dts
> @@ -719,6 +719,7 @@ &sdhc_1 {
>  	vmmc-supply = <&vreg_l8a>;
>  	vqmmc-supply = <&vreg_s4a>;
>  
> +	supports-cqe;
>  	non-removable;
>  	no-sd;
>  	no-sdio;

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260616130347.3096034-1-monish.chunara@oss.qualcomm.com?part=1