RE: Re: [RESEND v4 1/2] dt-bindings: imx6q-pcie: add one regulator used to power up pcie phy

From: Richard Zhu
Date: Fri May 07 2021 - 01:56:56 EST



> Subject: Re: [RESEND v4 1/2] dt-bindings: imx6q-pcie: add one
> regulator used to power up pcie phy
> On Thu, May 06, 2021 at 06:08:24PM +0200, Lucas Stach wrote:
> > Hi Lorenzo,
> >
> > have those two patches fallen through some crack? AFAICS they are gone
> > from patchwork, but I also can't find them in any branch in the usual
> > git repos.
>
> They were marked "accepted" in patchwork but must have fallen through the
> cracks. I reset them to "new" and assigned to Lorenzo.
[Richard Zhu] Thanks for your help.

>
> Neither one follows the subject line capitalization conventions.
>
> The subject line of this patch (1/2) doesn't really make sense. I
> *think* this adds a property ("vph-supply") to indicate which regulator supplys
> power to the PHY.
>
> > Am Dienstag, dem 30.03.2021 um 16:08 +0800 schrieb Richard Zhu:
> > > Both 1.8v and 3.3v power supplies can be used by i.MX8MQ PCIe PHY.
> > > In default, the PCIE_VPH voltage is suggested to be 1.8v refer to
> > > data sheet. When PCIE_VPH is supplied by 3.3v in the HW schematic
> > > design, the VREG_BYPASS bits of GPR registers should be cleared from
> > > default value 1b'1 to 1b'0. Thus, the internal 3v3 to 1v8 translator
> > > would be turned on.
>
> This commit log doesn't describe the patch, either. Maybe something like
> this:
>
> dt-bindings: imx6q-pcie: Add "vph-supply" for PHY supply voltage
>
> The i.MX8MQ PCIe PHY can use either a 1.8V or a 3.3V power supply.
> Add a "vph-supply" property to indicate which regulator supplies
> power for the PHY.
>
[Richard Zhu] Okay, will be changed as this way.

> > > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > > Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> > > ---
> > > Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt | 3 +++
> > > 1 file changed, 3 insertions(+)
> > >
> > > diff --git
> > > a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> > > b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> > > index de4b2baf91e8..d8971ab99274 100644
> > > --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> > > +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> > > @@ -38,6 +38,9 @@ Optional properties:
> > > The regulator will be enabled when initializing the PCIe host and
> > > disabled either as part of the init process or when shutting down the
> > > host.
> > > +- vph-supply: Should specify the regulator in charge of VPH one of
> > > +the three
> > > + PCIe PHY powers. This regulator can be supplied by both 1.8v and
> > > +3.3v voltage
> > > + supplies.
>
> Just going by examples for other drivers, I think this should say something like
> this:
>
> - vph-supply: Regulator for i.MX8MQ PCIe PHY. May supply either
> 1.8V or 3.3V.
>
> You mentioned "one of the three PCIe PHY powers"; I don't know what that
> means, so I don't know whether it's important to include.
>
> I also don't know what "vph" means; if the "ph" is part of "phy", it'd be nicer
> to include the "y", so it would be "vphy-supply".
[Richard Zhu] There are three power supplies in total required by the PHY.
- vp: PHY analog and digital supply
- vptxN: PHY transmit supply
-vph: High-voltage power supply.
Only vph is handled by SW here.

BR
Richard
>
> > > Additional required properties for imx6sx-pcie:
> > > - clock names: Must include the following additional entries: