spacemit: P1 PMIC support on Banana pi F3 testing

[Anand Moon]

Hi Alex

On Fri, 25 Jul 2025 at 15:19, Anand Moon <linux.amoon at gmail.com> wrote:
>
> Hi Alex,
>
> On Fri, 25 Jul 2025 at 07:26, Alex Elder <elder at riscstar.com> wrote:
> >
> > On 7/24/25 4:56 AM, Anand Moon wrote:
> > > Hi Alex,
> > >
> > > Thank you for your work on the P1 PMIC patch for Spacemit K1 SoC - Banana Pi F3.
> > >
> > > I've been testing your patch series for the Banana Pi F3 [0] to enable SD card
> > > and eMMC functionality,
> > >
> > > [0] https://patchew.org/linux/20250710175107.1280221-1-elder@riscstar.com/
> > >
> > > While debugging, I cross-referenced the patch with the BPI-F3-V3 board
> > > schematic [1]
> > > and noticed several discrepancies in the power configuration:
> > >
> > > [1] https://drive.google.com/file/d/19iLJ5xnCB_oK8VeQjkPGjzAn39WYyylv/view
> > >
> > > Incorrect Voltage Ranges: The minimum and maximum voltage values for
> > > multiple regulators
> > > (including BUCKs, ALDOs, and DLDOs) In the patch, do not match the
> > > specifications in
> > > the schematic's power tree.
> >
> > I really appreciate you checking this.
> >
> > The values I used were derived from the vendor code that I
> > started with.  I was assured that this baseline worked on
> > the Banana Pi BPI-F3.
> >
> I am just following examples from SoC like Rockchip and Samsung.
>
> > For the record, I *do* have a functioning SD card and eMMC.
> > I'm not sure just now what you are using differs from what
> > I am using.
> >
> > I would like to understand and reconcile the differences you
> > point out but I'm not able to do that at this time; maybe
> > next week.
>
> You are using the default  ranges  0.5~3.4V at 3.5A.
> But in the schematic's power tree, components such as P1 (U1401) and K1 (Uxxx)
> specify precise voltage ranges, for example:
> 0.9 V ± 1%
> 1.8 V ± 1%
> 3.3 V ± 1%
>

I might be mistaken, but I came across what seems to be the SpacemiT
P1 datasheet [0].
Unfortunately, I’m not able to understand Chinese.

[0] https://developer.spacemit.com/documentation?token=Q4uNwF9a6idIo5k9U0AcK4iXn3b&type=pdf

I suspect the driver configuration might still be incomplete, as there appear
to be certain register bits that need to be set for proper functionality.
That said, I could be mistaken.

If you have access to this document plz share.

Thanks
-Anand