[PATCH net-next v4 0/4] RGMII Internal delay common property

[PATCH net-next v4 0/4] RGMII Internal delay common property

[Dan Murphy]

Hello

The RGMII internal delay is a common setting found in most RGMII capable PHY
devices.  It was found that many vendor specific device tree properties exist
to do the same function. This creates a common property to be used for PHY's
that have tunable internal delays for the Rx and Tx paths.

Dan Murphy (4):
  dt-bindings: net: Add tx and rx internal delays
  net: phy: Add a helper to return the index for of the internal delay
  dt-bindings: net: Add RGMII internal delay for DP83869
  net: dp83869: Add RGMII internal delay configuration

 .../bindings/net/ethernet-controller.yaml     | 14 ++++
 .../devicetree/bindings/net/ti,dp83869.yaml   | 16 ++++
 drivers/net/phy/dp83869.c                     | 82 ++++++++++++++++++-
 drivers/net/phy/phy_device.c                  | 51 ++++++++++++
 include/linux/phy.h                           |  2 +
 5 files changed, 162 insertions(+), 3 deletions(-)

-- 
2.26.2

[PATCH net-next v4 1/4] dt-bindings: net: Add tx and rx internal delays

[Dan Murphy]

tx-internal-delays and rx-internal-delays are a common setting for RGMII
capable devices.

These properties are used when the phy-mode or phy-controller is set to
rgmii-id, rgmii-rxid or rgmii-txid.  These modes indicate to the
controller that the PHY will add the internal delay for the connection.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
---
 .../bindings/net/ethernet-controller.yaml          | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/ethernet-controller.yaml b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
index ac471b60ed6a..70702a4ef5e8 100644
--- a/Documentation/devicetree/bindings/net/ethernet-controller.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
@@ -143,6 +143,20 @@ properties:
       Specifies the PHY management type. If auto is set and fixed-link
       is not specified, it uses MDIO for management.
 
+  rx-internal-delay-ps:
+    $ref: /schemas/types.yaml#definitions/uint32
+    description: |
+      RGMII Receive PHY Clock Delay defined in pico seconds.  This is used for
+      PHY's that have configurable RX internal delays.  This property is only
+      used when the phy-mode or phy-connection-type is rgmii-id or rgmii-rxid.
+
+  tx-internal-delay-ps:
+    $ref: /schemas/types.yaml#definitions/uint32
+    description: |
+      RGMII Transmit PHY Clock Delay defined in pico seconds.  This is used for
+      PHY's that have configurable TX internal delays.  This property is only
+      used when the phy-mode or phy-connection-type is rgmii-id or rgmii-txid.
+
   fixed-link:
     allOf:
       - if:
-- 
2.26.2

Re: [PATCH net-next v4 1/4] dt-bindings: net: Add tx and rx internal delays

[Rob Herring]

On Wed, May 27, 2020 at 11:49:31AM -0500, Dan Murphy wrote:
> tx-internal-delays and rx-internal-delays are a common setting for RGMII
> capable devices.
> 
> These properties are used when the phy-mode or phy-controller is set to
> rgmii-id, rgmii-rxid or rgmii-txid.  These modes indicate to the
> controller that the PHY will add the internal delay for the connection.
> 
> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
>  .../bindings/net/ethernet-controller.yaml          | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/ethernet-controller.yaml b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
> index ac471b60ed6a..70702a4ef5e8 100644
> --- a/Documentation/devicetree/bindings/net/ethernet-controller.yaml
> +++ b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
> @@ -143,6 +143,20 @@ properties:
>        Specifies the PHY management type. If auto is set and fixed-link
>        is not specified, it uses MDIO for management.
>  
> +  rx-internal-delay-ps:
> +    $ref: /schemas/types.yaml#definitions/uint32
> +    description: |
> +      RGMII Receive PHY Clock Delay defined in pico seconds.  This is used for
> +      PHY's that have configurable RX internal delays.  This property is only
> +      used when the phy-mode or phy-connection-type is rgmii-id or rgmii-rxid.

Isn't this a property of the phy (this is the controller schema)? Looks 
like we have similar properties already and they go in phy nodes. Would 
be good to have a standard property, but let's be clear where it goes.

We need to add '-ps' as a standard unit suffix (in dt-schema) and then a 
type is not needed here.

Rob

Re: [PATCH net-next v4 1/4] dt-bindings: net: Add tx and rx internal delays

[Dan Murphy]

Rob

On 5/29/20 1:25 PM, Rob Herring wrote:
> On Wed, May 27, 2020 at 11:49:31AM -0500, Dan Murphy wrote:
>> tx-internal-delays and rx-internal-delays are a common setting for RGMII
>> capable devices.
>>
>> These properties are used when the phy-mode or phy-controller is set to
>> rgmii-id, rgmii-rxid or rgmii-txid.  These modes indicate to the
>> controller that the PHY will add the internal delay for the connection.
>>
>> Signed-off-by: Dan Murphy <dmurphy@ti.com>
>> ---
>>   .../bindings/net/ethernet-controller.yaml          | 14 ++++++++++++++
>>   1 file changed, 14 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/net/ethernet-controller.yaml b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
>> index ac471b60ed6a..70702a4ef5e8 100644
>> --- a/Documentation/devicetree/bindings/net/ethernet-controller.yaml
>> +++ b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
>> @@ -143,6 +143,20 @@ properties:
>>         Specifies the PHY management type. If auto is set and fixed-link
>>         is not specified, it uses MDIO for management.
>>   
>> +  rx-internal-delay-ps:
>> +    $ref: /schemas/types.yaml#definitions/uint32
>> +    description: |
>> +      RGMII Receive PHY Clock Delay defined in pico seconds.  This is used for
>> +      PHY's that have configurable RX internal delays.  This property is only
>> +      used when the phy-mode or phy-connection-type is rgmii-id or rgmii-rxid.
> Isn't this a property of the phy (this is the controller schema)? Looks
> like we have similar properties already and they go in phy nodes. Would
> be good to have a standard property, but let's be clear where it goes.
>
> We need to add '-ps' as a standard unit suffix (in dt-schema) and then a
> type is not needed here.

This is a PHY specific property.

I will move them.

Dumb question but you can just point me to the manual about how and 
where to add the '-ps' to the dt-schema

Dan


> Rob

Re: [PATCH net-next v4 1/4] dt-bindings: net: Add tx and rx internal delays

[Rob Herring]

On Fri, May 29, 2020 at 1:24 PM Dan Murphy <dmurphy@ti.com> wrote:
>
> Rob
>
> On 5/29/20 1:25 PM, Rob Herring wrote:
> > On Wed, May 27, 2020 at 11:49:31AM -0500, Dan Murphy wrote:
> >> tx-internal-delays and rx-internal-delays are a common setting for RGMII
> >> capable devices.
> >>
> >> These properties are used when the phy-mode or phy-controller is set to
> >> rgmii-id, rgmii-rxid or rgmii-txid.  These modes indicate to the
> >> controller that the PHY will add the internal delay for the connection.
> >>
> >> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> >> ---
> >>   .../bindings/net/ethernet-controller.yaml          | 14 ++++++++++++++
> >>   1 file changed, 14 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/net/ethernet-controller.yaml b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
> >> index ac471b60ed6a..70702a4ef5e8 100644
> >> --- a/Documentation/devicetree/bindings/net/ethernet-controller.yaml
> >> +++ b/Documentation/devicetree/bindings/net/ethernet-controller.yaml
> >> @@ -143,6 +143,20 @@ properties:
> >>         Specifies the PHY management type. If auto is set and fixed-link
> >>         is not specified, it uses MDIO for management.
> >>
> >> +  rx-internal-delay-ps:
> >> +    $ref: /schemas/types.yaml#definitions/uint32
> >> +    description: |
> >> +      RGMII Receive PHY Clock Delay defined in pico seconds.  This is used for
> >> +      PHY's that have configurable RX internal delays.  This property is only
> >> +      used when the phy-mode or phy-connection-type is rgmii-id or rgmii-rxid.
> > Isn't this a property of the phy (this is the controller schema)? Looks
> > like we have similar properties already and they go in phy nodes. Would
> > be good to have a standard property, but let's be clear where it goes.
> >
> > We need to add '-ps' as a standard unit suffix (in dt-schema) and then a
> > type is not needed here.
>
> This is a PHY specific property.
>
> I will move them.
>
> Dumb question but you can just point me to the manual about how and
> where to add the '-ps' to the dt-schema

Here[1], but looks like I already added it. I'd checked the old kernel
version (property-units.txt) which didn't have it.

Rob

[1] https://github.com/devicetree-org/dt-schema/blob/master/schemas/property-units.yaml#L48

[PATCH net-next v4 2/4] net: phy: Add a helper to return the index for of the internal delay

[Dan Murphy]

Add a helper function that will return the index in the array for the
passed in internal delay value.  The helper requires the array, size and
delay value.

The helper will then return the index for the exact match or return the
index for the index to the closest smaller value.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
---
 drivers/net/phy/phy_device.c | 51 ++++++++++++++++++++++++++++++++++++
 include/linux/phy.h          |  2 ++
 2 files changed, 53 insertions(+)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 6b30d205642f..3f3bd0fea53c 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -2661,6 +2661,57 @@ void phy_get_pause(struct phy_device *phydev, bool *tx_pause, bool *rx_pause)
 }
 EXPORT_SYMBOL(phy_get_pause);
 
+/**
+ * phy_get_delay_index - returns the index of the internal delay
+ * @phydev: phy_device struct
+ * @delay_values: array of delays the PHY supports
+ * @size: the size of the delay array
+ * @int_delay: the internal delay to be looked up
+ *
+ * Returns the index within the array of internal delay passed in.
+ * The array must be in ascending order.
+ * Return errno if the delay is invalid or cannot be found.
+ */
+s32 phy_get_delay_index(struct phy_device *phydev, const int *delay_values,
+			int size, int int_delay)
+{
+	int i;
+
+	if (int_delay < 0)
+		return -EINVAL;
+
+	if (size <= 0)
+		return -EINVAL;
+
+	if (int_delay < delay_values[0] || int_delay > delay_values[size - 1]) {
+		phydev_err(phydev, "Delay %d is out of range\n", int_delay);
+		return -EINVAL;
+	}
+
+	if (int_delay == delay_values[0])
+		return 0;
+
+	for (i = 1; i < size; i++) {
+		if (int_delay == delay_values[i])
+			return i;
+
+		/* Find an approximate index by looking up the table */
+		if (int_delay > delay_values[i - 1] &&
+		    int_delay < delay_values[i]) {
+			if (int_delay - delay_values[i - 1] <
+			    delay_values[i] - int_delay)
+				return i - 1;
+			else
+				return i;
+		}
+	}
+
+	phydev_err(phydev, "error finding internal delay index for %d\n",
+		   int_delay);
+	return -EINVAL;
+}
+EXPORT_SYMBOL(phy_get_delay_index);
+
 static bool phy_drv_supports_irq(struct phy_driver *phydrv)
 {
 	return phydrv->config_intr && phydrv->ack_interrupt;
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 2bcdf19ed3b4..2058ed11f7dd 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1408,6 +1408,8 @@ void phy_set_asym_pause(struct phy_device *phydev, bool rx, bool tx);
 bool phy_validate_pause(struct phy_device *phydev,
 			struct ethtool_pauseparam *pp);
 void phy_get_pause(struct phy_device *phydev, bool *tx_pause, bool *rx_pause);
+int phy_get_delay_index(struct phy_device *phydev, const int *delay_values,
+			int size, int delay);
 void phy_resolve_pause(unsigned long *local_adv, unsigned long *partner_adv,
 		       bool *tx_pause, bool *rx_pause);
 
-- 
2.26.2

[PATCH net-next v4 3/4] dt-bindings: net: Add RGMII internal delay for DP83869

[Dan Murphy]

Add the internal delay values into the header and update the binding
with the internal delay properties.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
---
 .../devicetree/bindings/net/ti,dp83869.yaml      | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/ti,dp83869.yaml b/Documentation/devicetree/bindings/net/ti,dp83869.yaml
index 5b69ef03bbf7..2971dd3fc039 100644
--- a/Documentation/devicetree/bindings/net/ti,dp83869.yaml
+++ b/Documentation/devicetree/bindings/net/ti,dp83869.yaml
@@ -64,6 +64,20 @@ properties:
        Operational mode for the PHY.  If this is not set then the operational
        mode is set by the straps. see dt-bindings/net/ti-dp83869.h for values
 
+  rx-internal-delay-ps:
+    $ref: "#/properties/rx-internal-delay-ps"
+    description: Delay is in pico seconds
+    enum: [ 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2250, 2500, 2750, 3000,
+            3250, 3500, 3750, 4000 ]
+    default: 2000
+
+  tx-internal-delay-ps:
+    $ref: "#/properties/tx-internal-delay-ps"
+    description: Delay is in pico seconds
+    enum: [ 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2250, 2500, 2750, 3000,
+            3250, 3500, 3750, 4000 ]
+    default: 2000
+
 required:
   - reg
 
@@ -80,5 +94,7 @@ examples:
         ti,op-mode = <DP83869_RGMII_COPPER_ETHERNET>;
         ti,max-output-impedance = "true";
         ti,clk-output-sel = <DP83869_CLK_O_SEL_CHN_A_RCLK>;
+        rx-internal-delay-ps = <2000>;
+        tx-internal-delay-ps = <2000>;
       };
     };
-- 
2.26.2

Re: [PATCH net-next v4 3/4] dt-bindings: net: Add RGMII internal delay for DP83869

[Rob Herring]

On Wed, May 27, 2020 at 11:49:33AM -0500, Dan Murphy wrote:
> Add the internal delay values into the header and update the binding
> with the internal delay properties.
> 
> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
>  .../devicetree/bindings/net/ti,dp83869.yaml      | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/ti,dp83869.yaml b/Documentation/devicetree/bindings/net/ti,dp83869.yaml
> index 5b69ef03bbf7..2971dd3fc039 100644
> --- a/Documentation/devicetree/bindings/net/ti,dp83869.yaml
> +++ b/Documentation/devicetree/bindings/net/ti,dp83869.yaml
> @@ -64,6 +64,20 @@ properties:
>         Operational mode for the PHY.  If this is not set then the operational
>         mode is set by the straps. see dt-bindings/net/ti-dp83869.h for values
>  
> +  rx-internal-delay-ps:
> +    $ref: "#/properties/rx-internal-delay-ps"

This just creates a circular reference which probably blows up.

> +    description: Delay is in pico seconds
> +    enum: [ 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2250, 2500, 2750, 3000,
> +            3250, 3500, 3750, 4000 ]
> +    default: 2000
> +
> +  tx-internal-delay-ps:
> +    $ref: "#/properties/tx-internal-delay-ps"
> +    description: Delay is in pico seconds
> +    enum: [ 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2250, 2500, 2750, 3000,
> +            3250, 3500, 3750, 4000 ]
> +    default: 2000
> +
>  required:
>    - reg
>  
> @@ -80,5 +94,7 @@ examples:
>          ti,op-mode = <DP83869_RGMII_COPPER_ETHERNET>;
>          ti,max-output-impedance = "true";
>          ti,clk-output-sel = <DP83869_CLK_O_SEL_CHN_A_RCLK>;
> +        rx-internal-delay-ps = <2000>;
> +        tx-internal-delay-ps = <2000>;
>        };
>      };
> -- 
> 2.26.2
> 

Re: [PATCH net-next v4 3/4] dt-bindings: net: Add RGMII internal delay for DP83869

[Dan Murphy]

Rob

On 5/29/20 2:03 PM, Rob Herring wrote:
> On Wed, May 27, 2020 at 11:49:33AM -0500, Dan Murphy wrote:
>> Add the internal delay values into the header and update the binding
>> with the internal delay properties.
>>
>> Signed-off-by: Dan Murphy <dmurphy@ti.com>
>> ---
>>   .../devicetree/bindings/net/ti,dp83869.yaml      | 16 ++++++++++++++++
>>   1 file changed, 16 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/net/ti,dp83869.yaml b/Documentation/devicetree/bindings/net/ti,dp83869.yaml
>> index 5b69ef03bbf7..2971dd3fc039 100644
>> --- a/Documentation/devicetree/bindings/net/ti,dp83869.yaml
>> +++ b/Documentation/devicetree/bindings/net/ti,dp83869.yaml
>> @@ -64,6 +64,20 @@ properties:
>>          Operational mode for the PHY.  If this is not set then the operational
>>          mode is set by the straps. see dt-bindings/net/ti-dp83869.h for values
>>   
>> +  rx-internal-delay-ps:
>> +    $ref: "#/properties/rx-internal-delay-ps"
> This just creates a circular reference which probably blows up.

dt_binding_check did not have an issue with this.

But I will remove it

Dan

[PATCH net-next v4 4/4] net: dp83869: Add RGMII internal delay configuration

[Dan Murphy]

Add RGMII internal delay configuration for Rx and Tx.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
---
 drivers/net/phy/dp83869.c | 82 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 79 insertions(+), 3 deletions(-)

diff --git a/drivers/net/phy/dp83869.c b/drivers/net/phy/dp83869.c
index cfb22a21a2e6..ba1e3d599888 100644
--- a/drivers/net/phy/dp83869.c
+++ b/drivers/net/phy/dp83869.c
@@ -64,6 +64,10 @@
 #define DP83869_RGMII_TX_CLK_DELAY_EN		BIT(1)
 #define DP83869_RGMII_RX_CLK_DELAY_EN		BIT(0)
 
+/* RGMIIDCTL */
+#define DP83869_RGMII_CLK_DELAY_SHIFT		4
+#define DP83869_CLK_DELAY_DEF			7
+
 /* STRAP_STS1 bits */
 #define DP83869_STRAP_OP_MODE_MASK		GENMASK(2, 0)
 #define DP83869_STRAP_STS1_RESERVED		BIT(11)
@@ -78,9 +82,6 @@
 #define DP83869_PHYCR_FIFO_DEPTH_MASK	GENMASK(15, 12)
 #define DP83869_PHYCR_RESERVED_MASK	BIT(11)
 
-/* RGMIIDCTL bits */
-#define DP83869_RGMII_TX_CLK_DELAY_SHIFT	4
-
 /* IO_MUX_CFG bits */
 #define DP83869_IO_MUX_CFG_IO_IMPEDANCE_CTRL	0x1f
 
@@ -99,6 +100,10 @@
 #define DP83869_OP_MODE_MII			BIT(5)
 #define DP83869_SGMII_RGMII_BRIDGE		BIT(6)
 
+static const int dp83869_internal_delay[] = {250, 500, 750, 1000, 1250, 1500,
+					     1750, 2000, 2250, 2500, 2750, 3000,
+					     3250, 3500, 3750, 4000};
+
 enum {
 	DP83869_PORT_MIRRORING_KEEP,
 	DP83869_PORT_MIRRORING_EN,
@@ -108,6 +113,8 @@ enum {
 struct dp83869_private {
 	int tx_fifo_depth;
 	int rx_fifo_depth;
+	s32 rx_id_delay;
+	s32 tx_id_delay;
 	int io_impedance;
 	int port_mirroring;
 	bool rxctrl_strap_quirk;
@@ -232,6 +239,22 @@ static int dp83869_of_init(struct phy_device *phydev)
 				 &dp83869->tx_fifo_depth))
 		dp83869->tx_fifo_depth = DP83869_PHYCR_FIFO_DEPTH_4_B_NIB;
 
+	ret = of_property_read_u32(of_node, "rx-internal-delay-ps",
+				   &dp83869->rx_id_delay);
+	if (ret) {
+		dp83869->rx_id_delay =
+				dp83869_internal_delay[DP83869_CLK_DELAY_DEF];
+		ret = 0;
+	}
+
+	ret = of_property_read_u32(of_node, "tx-internal-delay-ps",
+				   &dp83869->tx_id_delay);
+	if (ret) {
+		dp83869->tx_id_delay =
+				dp83869_internal_delay[DP83869_CLK_DELAY_DEF];
+		ret = 0;
+	}
+
 	return ret;
 }
 #else
@@ -367,10 +390,35 @@ static int dp83869_configure_mode(struct phy_device *phydev,
 	return ret;
 }
 
+static int dp83869_get_delay(struct phy_device *phydev)
+{
+	struct dp83869_private *dp83869 = phydev->priv;
+	int delay_size = ARRAY_SIZE(dp83869_internal_delay);
+	int tx_delay;
+	int rx_delay;
+
+	tx_delay = phy_get_delay_index(phydev, &dp83869_internal_delay[0],
+				       delay_size, dp83869->tx_id_delay);
+	if (tx_delay < 0) {
+		phydev_err(phydev, "Tx internal delay is invalid\n");
+		return tx_delay;
+	}
+
+	rx_delay = phy_get_delay_index(phydev, &dp83869_internal_delay[0],
+				       delay_size, dp83869->rx_id_delay);
+	if (rx_delay < 0) {
+		phydev_err(phydev, "Rx internal delay is invalid\n");
+		return rx_delay;
+	}
+
+	return rx_delay | tx_delay << DP83869_RGMII_CLK_DELAY_SHIFT;
+}
+
 static int dp83869_config_init(struct phy_device *phydev)
 {
 	struct dp83869_private *dp83869 = phydev->priv;
 	int ret, val;
+	int delay;
 
 	ret = dp83869_configure_mode(phydev, dp83869);
 	if (ret)
@@ -394,6 +442,34 @@ static int dp83869_config_init(struct phy_device *phydev)
 				     dp83869->clk_output_sel <<
 				     DP83869_IO_MUX_CFG_CLK_O_SEL_SHIFT);
 
+	if (phy_interface_is_rgmii(phydev)) {
+		delay = dp83869_get_delay(phydev);
+		if (delay < 0)
+			return delay;
+
+		ret = phy_write_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIIDCTL,
+				    delay);
+		if (ret)
+			return ret;
+
+		val = phy_read_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIICTL);
+		val &= ~(DP83869_RGMII_TX_CLK_DELAY_EN |
+			 DP83869_RGMII_RX_CLK_DELAY_EN);
+
+		if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID)
+			val |= (DP83869_RGMII_TX_CLK_DELAY_EN |
+				DP83869_RGMII_RX_CLK_DELAY_EN);
+
+		if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID)
+			val |= DP83869_RGMII_TX_CLK_DELAY_EN;
+
+		if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID)
+			val |= DP83869_RGMII_RX_CLK_DELAY_EN;
+
+		ret = phy_write_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIICTL,
+				    val);
+	}
+
 	return ret;
 }
 
-- 
2.26.2