Re: [PATCH 28/28] arm64: dts: qcom: talos-evk: Fix swapped USB QMP PHY vdda-phy/vdda-pll supplies

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] This problem wasn't introduced by this patch, but the patch provides an incomplete fix that leaves several QMP PHYs incorrectly configured. The commit message states that the QMP PHY expects the `vdda-pll` supply to be 1.2V, and the patch correctly sets `usb_qmpphy_2` to use `vreg_l11a` (which is configured for 1.23V - 1.26V). However, it fails to fix `usb_qmpphy`, `ufs_mem_phy`, and `pcie_phy` in the same file (`talos-evk-som.dtsi`), all of which continue to use `vreg_l12a` (which is configured for 1.8V - 1.89V) for their PLL supply. Furthermore, the sibling board `qcs615-ride.dts` also leaves both `usb_qmpphy` and `usb_qmpphy_2` configured with `vreg_l12a` (1.8V). This leaves the remaining PHYs exposed to a significant overvoltage (1.8V instead of 1.2V).
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--- Patch [28]: [PATCH 28/28] arm64: dts: qcom: talos-evk: Fix swapped USB QMP PHY vdda-phy/vdda-pll supplies ---
commit a8da26c25bde26c79bbdbc3a2692464d3f213cfd
Author: Manivannan Sadhasivam <[email protected]>

arm64: dts: qcom: talos-evk: Fix swapped USB QMP PHY vdda-phy/vdda-pll supplies

This commit corrects the swapped vdda-phy and vdda-pll supplies for the USB
QMP PHY on the QCS615 Talos EVK board. The patch ensures the vdda-pll supply
is fed 1.2V instead of 0.9V.

> diff --git a/arch/arm64/boot/dts/qcom/talos-evk-som.dtsi b/arch/arm64/boot/dts/qcom/talos-evk-som.dtsi
> index 294354c034c37..6469c6fa9f634 100644
> --- a/arch/arm64/boot/dts/qcom/talos-evk-som.dtsi
> +++ b/arch/arm64/boot/dts/qcom/talos-evk-som.dtsi
> @@ -589,8 +589,8 @@ &usb_qmpphy {
>  };
>  
>  &usb_qmpphy_2 {
> -	vdda-phy-supply = <&vreg_l11a>;
> -	vdda-pll-supply = <&vreg_l5a>;
> +	vdda-phy-supply = <&vreg_l5a>;
> +	vdda-pll-supply = <&vreg_l11a>;

[Severity: High]
This isn't a bug introduced by this patch, but does this provide an
incomplete fix that leaves several other QMP PHYs incorrectly configured?

The commit message states that the QMP PHY expects the vdda-pll supply to
be 1.2V, and this patch updates usb_qmpphy_2 to use vreg_l11a (1.23V - 1.26V).

However, looking just above this block in talos-evk-som.dtsi, usb_qmpphy
still uses vreg_l12a (which is configured for 1.8V):

&usb_qmpphy {
        vdda-phy-supply = <&vreg_l5a>;
        vdda-pll-supply = <&vreg_l12a>;

Similarly, ufs_mem_phy and pcie_phy also continue to use vreg_l12a for their
vdda-pll-supply.

Additionally, the sibling reference board qcs615-ride.dts leaves both
usb_qmpphy and usb_qmpphy_2 configured with vreg_l12a (1.8V).

Since supplying 1.8V to a PLL expecting 1.2V could expose the PHYs to a
significant overvoltage, or alternatively undervolt usb_qmpphy_2 if the SoC
natively requires 1.8V, should the remaining PHYs and sibling boards
be updated to the correct voltage as well?

>  
>  	status = "okay";
>  };

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=28