[PATCH v2 4/4] riscv: dts: spacemit: k1-bananapi-f3: Add vin-supply for PCIe 3.3V regulator

[Anand Moon]

Hi Chukun

On Wed, 13 May 2026 at 16:20, Chukun Pan <amadeus at jmu.edu.cn> wrote:
>
> Hi,
>
> > @@ -39,6 +39,7 @@ pcie_vcc_3v3: regulator-pcie-vcc3v3 {
> >               regulator-min-microvolt = <3300000>;
> >               regulator-max-microvolt = <3300000>;
> >               regulator-always-on;
> > +             vin-supply = <&reg_vcc5v0_sys>;
> >       };
>
> > Plese check power tree page 4
> >
> > USBVBUS->SY8386J UXXX -> PCIE_VCC3V3 for pcie vin source
> >
> > USBVBUS is power source from the typec port.
>
> So this isn't from VCC5V0_SYS. USBVBUS and DC_IN can be
> considered as the same power source.

I am not the hardware person. USBVBUS supplies 12V, and VCC5V0_SYS supplies 5V
As I understand it, SY8386J UXXX serves as a step-down DC/DC regulator
for your PCI device.

[1] https://datasheet4u.com/download_new.php?id=1604744

USBVBUS is the input for the PCIe source, so this should be vin-supply
= <&rreg_dc_in>;
It is as per the schematic

Thanks
-Anand