Re: [PATCH v6 7/8] arm64: dts: qcom: mahua: Add QREF regulator supplies to TCSR
From: Qiang Yu
Date: Mon Jun 29 2026 - 08:28:34 EST
On Mon, Jun 29, 2026 at 12:34:10PM +0200, Konrad Dybcio wrote:
> On 6/22/26 3:31 PM, Qiang Yu wrote:
> > On Mon, Jun 22, 2026 at 02:18:54PM +0200, Konrad Dybcio wrote:
> >> On 6/22/26 7:11 AM, Qiang Yu wrote:
> >>> Mahua has a different PCIe QREF topology from glymur. Override the TCSR
> >>> compatible to qcom,mahua-tcsr in mahua.dtsi, and wire up the required
> >>> LDO supplies for the PCIe clkref paths on the CRD board.
> >>>
> >>> Signed-off-by: Qiang Yu <qiang.yu@xxxxxxxxxxxxxxxx>
> >>> ---
> >>> arch/arm64/boot/dts/qcom/mahua-crd.dts | 15 +++++++++++++++
> >>> arch/arm64/boot/dts/qcom/mahua.dtsi | 4 ++++
> >>> 2 files changed, 19 insertions(+)
> >>>
> >>> diff --git a/arch/arm64/boot/dts/qcom/mahua-crd.dts b/arch/arm64/boot/dts/qcom/mahua-crd.dts
> >>> index 9c8244e892dd..8b42f5174b31 100644
> >>> --- a/arch/arm64/boot/dts/qcom/mahua-crd.dts
> >>> +++ b/arch/arm64/boot/dts/qcom/mahua-crd.dts
> >>> @@ -19,3 +19,18 @@ / {
> >>> model = "Qualcomm Technologies, Inc. Mahua CRD";
> >>> compatible = "qcom,mahua-crd", "qcom,mahua";
> >>> };
> >>> +
> >>> +&tcsr {
> >>> + vdda-qrefrpt0-0p9-supply = <&vreg_l2f_e1_0p83>;
> >>> + vdda-qrefrpt1-0p9-supply = <&vreg_l2f_e1_0p83>;
> >>> + vdda-qrefrpt2-0p9-supply = <&vreg_l2f_e1_0p83>;
> >>> + vdda-qrefrpt3-0p9-supply = <&vreg_l1f_e1_0p82>;
> >>> + vdda-qrefrpt4-0p9-supply = <&vreg_l2h_e0_0p72>;
> >>> + vdda-qrefrpt5-0p9-supply = <&vreg_l2h_e0_0p72>;
> >>> + vdda-qrefrx1-0p9-supply = <&vreg_l2f_e1_0p83>;
> >>> + vdda-qrefrx2-0p9-supply = <&vreg_l2f_e1_0p83>;
> >>> + vdda-qrefrx3-0p9-supply = <&vreg_l2h_e0_0p72>;
> >>> + vdda-qreftx1-0p9-supply = <&vreg_l1f_e1_0p82>;
> >>> + vdda-refgen3-0p9-supply = <&vreg_l1f_e1_0p82>;
> >>> + vdda-refgen3-1p2-supply = <&vreg_l4f_e1_1p08>;
> >>
> >> The supplies are correct, but QREF uses refgen4 on Mahua
> >>
> >
> > The instance is REFGEN4, but its regulator name is refgen3_xxx. Do you
> > think rename the supplies as vdda-refgen4-0p9-supply is better?
>
> Ah, I overlooked this. Maybe 4 could be better here, since the supplies
> that end up being assigned there match what we call refgen4 on Glymur.
>
> But there's no good answer, both options are terrible. Let's add a
> comment somewhere (in bindings?) describing this mess, perhaps like:
>
> # On Mahua, the REFGEN4 block is supplied through pads named REFGEN3
Okay, it's better to metion this in commit msg.
- Qiang Yu