Re: [PATCH v6 7/8] arm64: dts: qcom: mahua: Add QREF regulator supplies to TCSR

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 6/29/26 2:23 PM, Qiang Yu wrote:
> 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@oss.qualcomm.com>
>>>>> ---
>>>>>  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.

Doing so in both is good too!

Konrad