Re: [PATCH v2 3/3] arm64: dts: qcom: eliza: Enable Eliza MTP board support

[Abel Vesa]

On 26-03-17 21:13:22, Abel Vesa wrote:
> On 26-03-17 17:10:17, Dmitry Baryshkov wrote:
> > On Tue, Mar 17, 2026 at 10:47:18AM +0200, Abel Vesa wrote:
> > > On 26-03-13 17:51:37, Dmitry Baryshkov wrote:
> > > > On Fri, Mar 13, 2026 at 03:23:52PM +0200, Abel Vesa wrote:
> > > > > The MTP is a one of the boards that comes with the Eliza SoC.
> > > > > So add dedicated board dts for it.
> > > > > 
> > > > > The initial support enables:
> > > > > - UART debug console
> > > > > - Ob-board UFS storage
> > > > > - Qualcomm RPMh regulators (PMIC) and VPH_PWR
> > > > > - board specific clocks & reserved GPIO ranges
> > > > > 
> > > > > Co-developed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
> > > > > Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxxxxx>
> > > > > Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxxxxxxxx>
> > > > > ---
> > > > >  arch/arm64/boot/dts/qcom/Makefile      |   1 +
> > > > >  arch/arm64/boot/dts/qcom/eliza-mtp.dts | 407 +++++++++++++++++++++++++++++++++
> > > > >  2 files changed, 408 insertions(+)
> > > > > 
> > > > > +
> > > > > +		vreg_l12b: ldo12 {
> > > > > +			regulator-name = "vreg_l12b";
> > > > > +			/*
> > > > > +			 * Skip voltage voting for UFS VCC.
> > > > 
> > > > Please continue with 'why?'
> > > 
> > > Actually, I think I'm going to drop the comment and add the voltages range
> > > in here.
> > > 
> > > For some reason, when I added these, I considered that if other platforms
> > > are skipping the voltage voting, Eliza should do that too. But now that I
> > > took another look, I really don't think the voltage voting should be
> > > skipped at all.
> > > 
> > > Downstream does the voting as well.
> > > 
> > > So I'm going to add the following in the next version:
> > > 
> > > regulator-min-microvolt = <2400000>;
> > > regulator-max-microvolt = <3300000>;
> > > 
> > > Thanks for pointing this out.
> > 
> > FWIW I consider boards with different UFS PHYs to be different boards
> > and so there should be an overlay changing the supplies for the
> > non-standard version.
> 
> Yep, me too.
> 
> I'll send the next version tomorrow with the range mentioned above in.

Sorry for the back and forth on this.

Just had this bit explained to me by the UFS folks.

So the MTP can have different UFS devices which support different
versions. The UFS devices, depending on the UFS version supported,
need different voltages. Bootloader will pick the right voltage
and we should rely on that. That is the reason for not describing the
voltage range.

Now, with this in mind, I think the overlay for each different UFS device
is a bit of an overkill. But maybe I'm wrong.

So if you are okay with this explanation, I'll fix the comment to
explain why and respin ...