[PATCH] arm64: dts: ti: k3-am62d2-evm: Fix missing RX delay for DP83867 PHY

[PATCH] arm64: dts: ti: k3-am62d2-evm: Fix missing RX delay for DP83867 PHY

[Siddharth Vadapalli]

MAC Ports 1 and 2 of the CPSW3G Ethernet Switch in the AM62D2 SoC are both
connected to different instances of the DP83867 Ethernet PHY on the AM62D2
EVM, with the 'phy-mode' set to 'rgmii-id'. The DP83867 Ethernet PHY has to
add a 2 nanosecond delay on receive (from wire) based on the EVM design.

Since the device driver for the DP83867 Ethernet PHY coincidentally assumes
that the a 2 nanosecond receive delay has to be added in the absence of the
'ti,rx-internal-delay' property, Ethernet is functional.

However, since the device-tree is intended to describe the Hardware, and,
the device driver for the DP83867 Ethernet PHY may change in the future,
add the 'ti,rx-internal-delay' property and assign it the value
'DP83867_RGMIIDCTL_2_00_NS' which corresponds to a 2 nanosecond
delay.

Fixes: 1544bca2f188 ("arm64: dts: ti: Add support for AM62D2-EVM")
Cc: <stable@vger.kernel.org>
Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
---

Hello,

This patch is based on commit
24d479d26b25 Linux 6.19-rc6
of Mainline Linux.

Patch has been tested on the AM62D2 EVM verifying Ethernet functionality in
the form of NFS (Network File System) mounted using the CPSW3G Ethernet
interface 'eth0'. Test Logs:
https://gist.github.com/Siddharth-Vadapalli-at-TI/04c51da22c0a05f7fc930afc98997571

Regards,
Siddharth.

 arch/arm64/boot/dts/ti/k3-am62d2-evm.dts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts b/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts
index 2b233bc0323d..17c64af4f97b 100644
--- a/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts
+++ b/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts
@@ -649,12 +649,14 @@ &cpsw3g_mdio {
 
 	cpsw3g_phy0: ethernet-phy@0 {
 		reg = <0>;
+		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_00_NS>;
 		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
 		ti,min-output-impedance;
 	};
 
 	cpsw3g_phy1: ethernet-phy@3 {
 		reg = <3>;
+		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_00_NS>;
 		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
 		ti,min-output-impedance;
 	};
-- 
2.51.1

Re: [EXTERNAL] [PATCH] arm64: dts: ti: k3-am62d2-evm: Fix missing RX delay for DP83867 PHY

[Hari Prasath]

On 20/01/26 11:43 am, Siddharth Vadapalli wrote:
> MAC Ports 1 and 2 of the CPSW3G Ethernet Switch in the AM62D2 SoC are 
> both connected to different instances of the DP83867 Ethernet PHY on the 
> AM62D2 EVM, with the 'phy-mode' set to 'rgmii-id'. The DP83867 Ethernet 
> PHY has to add a 2 nanosecond
> ZjQcmQRYFpfptBannerStart
> This message was sent from outside of Texas Instruments.
> Do not click links or open attachments unless you recognize the source 
> of this email and know the content is safe.
> Report Suspicious
> <https://us-phishalarm-ewt.proofpoint.com/EWT/v1/G3vK! 
> uRdqXRfPtm07agZk_PPjvDYD9oe_mpoIkkjINUyRhGSu--0mQdy1pi4MPng- 
> ix3RK2L1V3y4DrnTdaCm8zj7QGx0QX2i$>
> ZjQcmQRYFpfptBannerEnd
> 
> MAC Ports 1 and 2 of the CPSW3G Ethernet Switch in the AM62D2 SoC are both
> connected to different instances of the DP83867 Ethernet PHY on the AM62D2
> EVM, with the 'phy-mode' set to 'rgmii-id'. The DP83867 Ethernet PHY has to
> add a 2 nanosecond delay on receive (from wire) based on the EVM design.
> 
> Since the device driver for the DP83867 Ethernet PHY coincidentally assumes
> that the a 2 nanosecond receive delay has to be added in the absence of the

'the' can be removed here.Verified this claim on default value in the 
driver without this DT property.

Reviewed-by: Hari Prasath Gujulan Elango <gehariprasath@ti.com>

> 'ti,rx-internal-delay' property, Ethernet is functional.
> 
> However, since the device-tree is intended to describe the Hardware, and,
> the device driver for the DP83867 Ethernet PHY may change in the future,
> add the 'ti,rx-internal-delay' property and assign it the value
> 'DP83867_RGMIIDCTL_2_00_NS' which corresponds to a 2 nanosecond
> delay.
> 
> Fixes: 1544bca2f188 ("arm64: dts: ti: Add support for AM62D2-EVM")
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
> ---
> 
> Hello,
> 
> This patch is based on commit
> 24d479d26b25 Linux 6.19-rc6
> of Mainline Linux.
> 
> Patch has been tested on the AM62D2 EVM verifying Ethernet functionality in
> the form of NFS (Network File System) mounted using the CPSW3G Ethernet
> interface 'eth0'. Test Logs:
> https://urldefense.com/v3/__https://gist.github.com/Siddharth-Vadapalli- 
> at-TI/04c51da22c0a05f7fc930afc98997571__;!!G3vK! 
> QTTK5TlfaumfenDPi727EMMDEuWq4go3k_u6HRWdaWchECwvYWQxiJzQtxgzKNMLr3FEjTj7x-zpSSw3CA$ <https://urldefense.com/v3/__https://gist.github.com/Siddharth-Vadapalli-at-TI/04c51da22c0a05f7fc930afc98997571__;!!G3vK!QTTK5TlfaumfenDPi727EMMDEuWq4go3k_u6HRWdaWchECwvYWQxiJzQtxgzKNMLr3FEjTj7x-zpSSw3CA$>
> 
> Regards,
> Siddharth.
> 
>   arch/arm64/boot/dts/ti/k3-am62d2-evm.dts | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts b/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts
> index 2b233bc0323d..17c64af4f97b 100644
> --- a/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts
> +++ b/arch/arm64/boot/dts/ti/k3-am62d2-evm.dts
> @@ -649,12 +649,14 @@ &cpsw3g_mdio {
>   
>   	cpsw3g_phy0: ethernet-phy@0 {
>   		reg = <0>;
> +		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_00_NS>;
>   		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
>   		ti,min-output-impedance;
>   	};
>   
>   	cpsw3g_phy1: ethernet-phy@3 {
>   		reg = <3>;
> +		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_00_NS>;
>   		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
>   		ti,min-output-impedance;
>   	};
> -- 
> 2.51.1
> 
> 

Re: [PATCH] arm64: dts: ti: k3-am62d2-evm: Fix missing RX delay for DP83867 PHY

[Siddharth Vadapalli]

On Tue, 2026-01-20 at 18:33 +0530, Hari Prasath wrote:
> On 20/01/26 11:43 am, Siddharth Vadapalli wrote:
> > MAC Ports 1 and 2 of the CPSW3G Ethernet Switch in the AM62D2 SoC are 
> > both connected to different instances of the DP83867 Ethernet PHY on the 
> > AM62D2 EVM, with the 'phy-mode' set to 'rgmii-id'. The DP83867 Ethernet 
> > PHY has to add a 2 nanosecond
> > ZjQcmQRYFpfptBannerStart
> > This message was sent from outside of Texas Instruments.
> > Do not click links or open attachments unless you recognize the source 
> > of this email and know the content is safe.
> > Report Suspicious
> > <https://us-phishalarm-ewt.proofpoint.com/EWT/v1/G3vK! 
> > uRdqXRfPtm07agZk_PPjvDYD9oe_mpoIkkjINUyRhGSu--0mQdy1pi4MPng- 
> > ix3RK2L1V3y4DrnTdaCm8zj7QGx0QX2i$>
> > ZjQcmQRYFpfptBannerEnd
> > 
> > MAC Ports 1 and 2 of the CPSW3G Ethernet Switch in the AM62D2 SoC are both
> > connected to different instances of the DP83867 Ethernet PHY on the AM62D2
> > EVM, with the 'phy-mode' set to 'rgmii-id'. The DP83867 Ethernet PHY has to
> > add a 2 nanosecond delay on receive (from wire) based on the EVM design.
> > 
> > Since the device driver for the DP83867 Ethernet PHY coincidentally assumes
> > that the a 2 nanosecond receive delay has to be added in the absence of the
> 
> 'the' can be removed here.Verified this claim on default value in the 
> driver without this DT property.

Thank you for pointing this out. While rephrasing the sentence, I forgot to
remove 'the'.

> 
> Reviewed-by: Hari Prasath Gujulan Elango <gehariprasath@ti.com>

Thank you for reviewing the patch. I will fix the commit message and
include your tag in the v2 patch.

Regards,
Siddharth.

Re: [PATCH] arm64: dts: ti: k3-am62d2-evm: Fix missing RX delay for DP83867 PHY

[Siddharth Vadapalli]

On Tue, 2026-01-20 at 18:42 +0530, Siddharth Vadapalli wrote:
> On Tue, 2026-01-20 at 18:33 +0530, Hari Prasath wrote:
> > On 20/01/26 11:43 am, Siddharth Vadapalli wrote:
> > > MAC Ports 1 and 2 of the CPSW3G Ethernet Switch in the AM62D2 SoC are 
> > > both connected to different instances of the DP83867 Ethernet PHY on the 
> > > AM62D2 EVM, with the 'phy-mode' set to 'rgmii-id'. The DP83867 Ethernet 
> > > PHY has to add a 2 nanosecond
> > > ZjQcmQRYFpfptBannerStart
> > > This message was sent from outside of Texas Instruments.
> > > Do not click links or open attachments unless you recognize the source 
> > > of this email and know the content is safe.
> > > Report Suspicious
> > > <https://us-phishalarm-ewt.proofpoint.com/EWT/v1/G3vK! 
> > > uRdqXRfPtm07agZk_PPjvDYD9oe_mpoIkkjINUyRhGSu--0mQdy1pi4MPng- 
> > > ix3RK2L1V3y4DrnTdaCm8zj7QGx0QX2i$>
> > > ZjQcmQRYFpfptBannerEnd
> > > 
> > > MAC Ports 1 and 2 of the CPSW3G Ethernet Switch in the AM62D2 SoC are both
> > > connected to different instances of the DP83867 Ethernet PHY on the AM62D2
> > > EVM, with the 'phy-mode' set to 'rgmii-id'. The DP83867 Ethernet PHY has to
> > > add a 2 nanosecond delay on receive (from wire) based on the EVM design.
> > > 
> > > Since the device driver for the DP83867 Ethernet PHY coincidentally assumes
> > > that the a 2 nanosecond receive delay has to be added in the absence of the
> > 
> > 'the' can be removed here.Verified this claim on default value in the 
> > driver without this DT property.
> 
> Thank you for pointing this out. While rephrasing the sentence, I forgot to
> remove 'the'.
> 
> > 
> > Reviewed-by: Hari Prasath Gujulan Elango <gehariprasath@ti.com>
> 
> Thank you for reviewing the patch. I will fix the commit message and
> include your tag in the v2 patch.

I have posted the v2 patch at:
https://lore.kernel.org/r/20260121054552.1650926-1-s-vadapalli@ti.com

Regards,
Siddharth.