Add support for standard tx-internal-delay-ps and rx-internal-delay-ps
properties on port nodes to allow fine-tuning of RGMII clock delays.
The GSWIP switch hardware supports delay values in 500 picosecond
increments from 0 to 3500 picoseconds, with a post-reset default of 2000
picoseconds for both TX and RX delays. The driver currently sets the
delay to 0 in case the PHY is setup to carry out the delay by the
corresponding interface modes ("rgmii-id", "rgmii-rxid", "rgmii-txid").
This corresponds to the driver changes that allow adjusting MII delays
using Device Tree properties instead of relying solely on the PHY
interface mode.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
v4:
* remove misleading defaults
v3:
* redefine ports node so properties are defined actually apply
* RGMII port with 2ps delay is 'rgmii-id' mode
.../bindings/net/dsa/lantiq,gswip.yaml | 31 +++++++++++++++++--
1 file changed, 28 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
index f3154b19af78..8ccbc8942eb3 100644
--- a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
+++ b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
@@ -6,8 +6,31 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
title: Lantiq GSWIP Ethernet switches
-allOf:
- - $ref: dsa.yaml#/$defs/ethernet-ports
+$ref: dsa.yaml#
+
+patternProperties:
+ "^(ethernet-)?ports$":
+ type: object
+ patternProperties:
+ "^(ethernet-)?port@[0-6]$":
+ $ref: dsa-port.yaml#
+ unevaluatedProperties: false
+
+ properties:
+ tx-internal-delay-ps:
+ enum: [0, 500, 1000, 1500, 2000, 2500, 3000, 3500]
+ description:
+ RGMII TX Clock Delay defined in pico seconds.
+ The delay lines adjust the MII clock vs. data timing.
+ If this property is not present the delay is determined by
+ the interface mode.
+ rx-internal-delay-ps:
+ enum: [0, 500, 1000, 1500, 2000, 2500, 3000, 3500]
+ description:
+ RGMII RX Clock Delay defined in pico seconds.
+ The delay lines adjust the MII clock vs. data timing.
+ If this property is not present the delay is determined by
+ the interface mode.
maintainers:
- Hauke Mehrtens <hauke@hauke-m.de>
@@ -113,8 +136,10 @@ examples:
port@0 {
reg = <0>;
label = "lan3";
- phy-mode = "rgmii";
+ phy-mode = "rgmii-id";
phy-handle = <&phy0>;
+ tx-internal-delay-ps = <2000>;
+ rx-internal-delay-ps = <2000>;
};
port@1 {
--
2.51.2On Thu, Oct 30, 2025 at 11:28:35AM +0000, Daniel Golle wrote:
> Add support for standard tx-internal-delay-ps and rx-internal-delay-ps
> properties on port nodes to allow fine-tuning of RGMII clock delays.
>
> The GSWIP switch hardware supports delay values in 500 picosecond
> increments from 0 to 3500 picoseconds, with a post-reset default of 2000
> picoseconds for both TX and RX delays. The driver currently sets the
> delay to 0 in case the PHY is setup to carry out the delay by the
> corresponding interface modes ("rgmii-id", "rgmii-rxid", "rgmii-txid").
>
> This corresponds to the driver changes that allow adjusting MII delays
> using Device Tree properties instead of relying solely on the PHY
> interface mode.
>
> Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> ---
> v4:
> * remove misleading defaults
>
> v3:
> * redefine ports node so properties are defined actually apply
> * RGMII port with 2ps delay is 'rgmii-id' mode
>
> .../bindings/net/dsa/lantiq,gswip.yaml | 31 +++++++++++++++++--
> 1 file changed, 28 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> index f3154b19af78..8ccbc8942eb3 100644
> --- a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> +++ b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> @@ -6,8 +6,31 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
>
> title: Lantiq GSWIP Ethernet switches
>
> -allOf:
> - - $ref: dsa.yaml#/$defs/ethernet-ports
I think you can keep this as you aren't adding custom properties.
> +$ref: dsa.yaml#
> +
> +patternProperties:
> + "^(ethernet-)?ports$":
> + type: object
> + patternProperties:
> + "^(ethernet-)?port@[0-6]$":
> + $ref: dsa-port.yaml#
> + unevaluatedProperties: false
And drop these lines. You may need 'additionalProperties: true' if the
tools warn.
> +
> + properties:
> + tx-internal-delay-ps:
> + enum: [0, 500, 1000, 1500, 2000, 2500, 3000, 3500]
> + description:
> + RGMII TX Clock Delay defined in pico seconds.
> + The delay lines adjust the MII clock vs. data timing.
> + If this property is not present the delay is determined by
> + the interface mode.
> + rx-internal-delay-ps:
> + enum: [0, 500, 1000, 1500, 2000, 2500, 3000, 3500]
> + description:
> + RGMII RX Clock Delay defined in pico seconds.
> + The delay lines adjust the MII clock vs. data timing.
> + If this property is not present the delay is determined by
> + the interface mode.
>
> maintainers:
> - Hauke Mehrtens <hauke@hauke-m.de>
> @@ -113,8 +136,10 @@ examples:
> port@0 {
> reg = <0>;
> label = "lan3";
> - phy-mode = "rgmii";
> + phy-mode = "rgmii-id";
> phy-handle = <&phy0>;
> + tx-internal-delay-ps = <2000>;
> + rx-internal-delay-ps = <2000>;
> };
>
> port@1 {
> --
> 2.51.2
On Thu, Oct 30, 2025 at 07:29:24PM -0500, Rob Herring wrote:
> On Thu, Oct 30, 2025 at 11:28:35AM +0000, Daniel Golle wrote:
> > Add support for standard tx-internal-delay-ps and rx-internal-delay-ps
> > properties on port nodes to allow fine-tuning of RGMII clock delays.
> >
> > The GSWIP switch hardware supports delay values in 500 picosecond
> > increments from 0 to 3500 picoseconds, with a post-reset default of 2000
> > picoseconds for both TX and RX delays. The driver currently sets the
> > delay to 0 in case the PHY is setup to carry out the delay by the
> > corresponding interface modes ("rgmii-id", "rgmii-rxid", "rgmii-txid").
> >
> > This corresponds to the driver changes that allow adjusting MII delays
> > using Device Tree properties instead of relying solely on the PHY
> > interface mode.
> >
> > Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> > ---
> > v4:
> > * remove misleading defaults
> >
> > v3:
> > * redefine ports node so properties are defined actually apply
> > * RGMII port with 2ps delay is 'rgmii-id' mode
> >
> > .../bindings/net/dsa/lantiq,gswip.yaml | 31 +++++++++++++++++--
> > 1 file changed, 28 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > index f3154b19af78..8ccbc8942eb3 100644
> > --- a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > +++ b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > @@ -6,8 +6,31 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
> >
> > title: Lantiq GSWIP Ethernet switches
> >
> > -allOf:
> > - - $ref: dsa.yaml#/$defs/ethernet-ports
>
> I think you can keep this as you aren't adding custom properties.
Nevermind, I see the next patch now...
On Thu, Oct 30, 2025 at 07:37:04PM -0500, Rob Herring wrote:
> On Thu, Oct 30, 2025 at 07:29:24PM -0500, Rob Herring wrote:
> > On Thu, Oct 30, 2025 at 11:28:35AM +0000, Daniel Golle wrote:
> > > Add support for standard tx-internal-delay-ps and rx-internal-delay-ps
> > > properties on port nodes to allow fine-tuning of RGMII clock delays.
> > >
> > > The GSWIP switch hardware supports delay values in 500 picosecond
> > > increments from 0 to 3500 picoseconds, with a post-reset default of 2000
> > > picoseconds for both TX and RX delays. The driver currently sets the
> > > delay to 0 in case the PHY is setup to carry out the delay by the
> > > corresponding interface modes ("rgmii-id", "rgmii-rxid", "rgmii-txid").
> > >
> > > This corresponds to the driver changes that allow adjusting MII delays
> > > using Device Tree properties instead of relying solely on the PHY
> > > interface mode.
> > >
> > > Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> > > ---
> > > v4:
> > > * remove misleading defaults
> > >
> > > v3:
> > > * redefine ports node so properties are defined actually apply
> > > * RGMII port with 2ps delay is 'rgmii-id' mode
> > >
> > > .../bindings/net/dsa/lantiq,gswip.yaml | 31 +++++++++++++++++--
> > > 1 file changed, 28 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > > index f3154b19af78..8ccbc8942eb3 100644
> > > --- a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > > +++ b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > > @@ -6,8 +6,31 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
> > >
> > > title: Lantiq GSWIP Ethernet switches
> > >
> > > -allOf:
> > > - - $ref: dsa.yaml#/$defs/ethernet-ports
> >
> > I think you can keep this as you aren't adding custom properties.
>
> Nevermind, I see the next patch now...
I suppose you mean [08/12] ("dt-bindings: net: dsa: lantiq,gswip: add
MaxLinear RMII refclk output property"), right?
The intention to divert from dsa.yaml#/$defs/ethernet-ports
already in this patch was to enforce the possible values of
{rx,tx}-internal-delay-ps.
Anyway, so you are saying I can keep the change in this patch? Or
should I just drop the constraints on the possible values of the
delays and only divert from dsa.yaml#/$defs/ethernet-ports once I'm
actually adding maxlinear,rmii-refclk-out?
On Fri, Oct 31, 2025 at 02:12:26AM +0000, Daniel Golle wrote:
> On Thu, Oct 30, 2025 at 07:37:04PM -0500, Rob Herring wrote:
> > On Thu, Oct 30, 2025 at 07:29:24PM -0500, Rob Herring wrote:
> > > On Thu, Oct 30, 2025 at 11:28:35AM +0000, Daniel Golle wrote:
> > > > Add support for standard tx-internal-delay-ps and rx-internal-delay-ps
> > > > properties on port nodes to allow fine-tuning of RGMII clock delays.
> > > >
> > > > The GSWIP switch hardware supports delay values in 500 picosecond
> > > > increments from 0 to 3500 picoseconds, with a post-reset default of 2000
> > > > picoseconds for both TX and RX delays. The driver currently sets the
> > > > delay to 0 in case the PHY is setup to carry out the delay by the
> > > > corresponding interface modes ("rgmii-id", "rgmii-rxid", "rgmii-txid").
> > > >
> > > > This corresponds to the driver changes that allow adjusting MII delays
> > > > using Device Tree properties instead of relying solely on the PHY
> > > > interface mode.
> > > >
> > > > Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> > > > ---
> > > > v4:
> > > > * remove misleading defaults
> > > >
> > > > v3:
> > > > * redefine ports node so properties are defined actually apply
> > > > * RGMII port with 2ps delay is 'rgmii-id' mode
> > > >
> > > > .../bindings/net/dsa/lantiq,gswip.yaml | 31 +++++++++++++++++--
> > > > 1 file changed, 28 insertions(+), 3 deletions(-)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > > > index f3154b19af78..8ccbc8942eb3 100644
> > > > --- a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > > > +++ b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
> > > > @@ -6,8 +6,31 @@ $schema: http://devicetree.org/meta-schemas/core.yaml#
> > > >
> > > > title: Lantiq GSWIP Ethernet switches
> > > >
> > > > -allOf:
> > > > - - $ref: dsa.yaml#/$defs/ethernet-ports
> > >
> > > I think you can keep this as you aren't adding custom properties.
> >
> > Nevermind, I see the next patch now...
>
> I suppose you mean [08/12] ("dt-bindings: net: dsa: lantiq,gswip: add
> MaxLinear RMII refclk output property"), right?
>
> The intention to divert from dsa.yaml#/$defs/ethernet-ports
> already in this patch was to enforce the possible values of
> {rx,tx}-internal-delay-ps.
>
> Anyway, so you are saying I can keep the change in this patch? Or
> should I just drop the constraints on the possible values of the
> delays and only divert from dsa.yaml#/$defs/ethernet-ports once I'm
> actually adding maxlinear,rmii-refclk-out?
You can keep it as-is, but strictly speaking, some of what's here is
only needed for [08/12]. Perhaps reverse the order of the patches. Then
it would be most of the changes here with the maxlinear,rmii-refclk-out
added, and then the 2nd patch is constraints on
{rx,tx}-internal-delay-ps.
Rob
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