Re: [PATCH v3 5/6] dt-bindings: mmc: sdhci-cadence: SD6 support

From: Piyush Malgujar
Date: Fri Mar 24 2023 - 11:26:13 EST


Hi Rob,

Thanks for the review comments.

On Tue, Feb 28, 2023 at 09:46:48AM -0600, Rob Herring wrote:
> On Mon, Feb 27, 2023 at 10:31:50AM -0800, Piyush Malgujar wrote:
> > From: Jayanthi Annadurai <jannadurai@xxxxxxxxxxx>
> >
> > Add support for SD6 controller support.
>
> On what h/w?
>

This has been used and tested on Marvell CN10K series SOCs.

> >
> > Signed-off-by: Jayanthi Annadurai <jannadurai@xxxxxxxxxxx>
> > Signed-off-by: Piyush Malgujar <pmalgujar@xxxxxxxxxxx>
> > ---
> > .../devicetree/bindings/mmc/cdns,sdhci.yaml | 24 +++++++++++++++++--
> > 1 file changed, 22 insertions(+), 2 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml b/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
> > index 8b1a0fdcb5e3e2e8b87d8d7678e37f3dad447fc1..0dba17c4f17f82c8ae68e46225ed72418e8361ff 100644
> > --- a/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
> > +++ b/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
> > @@ -4,7 +4,7 @@
> > $id: http://devicetree.org/schemas/mmc/cdns,sdhci.yaml#
> > $schema: http://devicetree.org/meta-schemas/core.yaml#
> >
> > -title: Cadence SD/SDIO/eMMC Host Controller (SD4HC)
> > +title: Cadence SD/SDIO/eMMC Host Controller (SD4HC, SD6HC)
> >
> > maintainers:
> > - Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> > @@ -18,7 +18,9 @@ properties:
> > - enum:
> > - microchip,mpfs-sd4hc
> > - socionext,uniphier-sd4hc
> > - - const: cdns,sd4hc
> > + - enum:
> > + - cdns,sd4hc
> > + - cdns,sd6hc
>
> Other than FPGA implementations IP vendor compatible strings are pretty
> much useless. Define a compatible for your h/w.
>

ok, will use Marvell specific string here.

> >
> > reg:
> > maxItems: 1
> > @@ -111,6 +113,24 @@ properties:
> > minimum: 0
> > maximum: 0x7f
> >
> > + cdns,iocell-input-delay-ps:
> > + description: Delay in ps across the input IO cells
> > +
> > + cdns,iocell-output-delay-ps:
> > + description: Delay in ps across the output IO cells
> > +
> > + cdns,delay-element-ps:
> > + description: Delay element in ps used for calculating phy timings
> > +
> > + cdns,read-dqs-cmd-delay-ps:
> > + description: Command delay used in HS200 tuning
> > +
> > + cdns,tune-val-start-ps:
> > + description: Staring value of data delay used in HS200 tuning
> > +
> > + cdns,tune-val-step-ps:
> > + description: Incremental value of data delay used in HS200 tuning
>
> Wouldn't any controller implementation need these possibly? IIRC, we
> have some common properties for this. If not, survey what we do have and
> come up with something common. Or you can imply all this from the h/w
> specific compatible you are going to add.
>

These parameters are for sd6 cadence controller, will add sd6 in the property
string so to imply it's specific to sd6hc.

> Rob

Thanks,
Piyush