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

[Hari Prasath <gehariprasath@ti.com>]

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
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> 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
> 
>