diff mbox series

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

Message ID 1617091701-6444-2-git-send-email-hongxing.zhu@nxp.com
State New
Headers show
Series add one regulator used to power up pcie phy | expand

Commit Message

Richard Zhu March 30, 2021, 8:08 a.m. UTC
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.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
---
 Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt | 3 +++
 1 file changed, 3 insertions(+)

Comments

Lucas Stach May 6, 2021, 4:08 p.m. UTC | #1
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.

Regards,
Lucas

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.
> 
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
> ---
>  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.
>  
> 
>  Additional required properties for imx6sx-pcie:
>  - clock names: Must include the following additional entries:
Bjorn Helgaas May 6, 2021, 9:01 p.m. UTC | #2
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.

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.

> > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
> > ---
> >  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".

> >  Additional required properties for imx6sx-pcie:
> >  - clock names: Must include the following additional entries:
diff mbox series

Patch

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