Re: [PATCH] MIPS: Loongson64: dts: fix phy-related definition of LS7A GMAC

[Thomas Bogendoerfer]

On Fri, Jan 02, 2026 at 11:52:43PM +0800, Icenowy Zheng wrote:
> Currently the LS7A GMAC device tree node lacks a proper phy-handle
> property pointing to the PHY node.
> 
> In addition, the phy-mode property specifies "rgmii" without any
> internal delay information, which means the board trace needs to add 2ns
> delay to the RGMII data lines; but that isn't known to happen on any
> Loongson board. The ACPI-based initialization codepath, which is used on
> LoongArch-based 3A5000 + 7A1000 hardwares, specifies "rgmii-id" phy
> mode, which should be the one we are using.
> 
> Add the lacking phy-handle property and set proper phy-mode.
> 
> Tested on a LS3A4000_7A1000_NUC_BOARD_V2.1 board with YT8521S PHY.
> 
> Signed-off-by: Icenowy Zheng <zhengxingda@xxxxxxxxxxx>
> ---
>  arch/mips/boot/dts/loongson/ls7a-pch.dtsi | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/mips/boot/dts/loongson/ls7a-pch.dtsi b/arch/mips/boot/dts/loongson/ls7a-pch.dtsi
> index ee71045883e7e..6dee85909f5a6 100644
> --- a/arch/mips/boot/dts/loongson/ls7a-pch.dtsi
> +++ b/arch/mips/boot/dts/loongson/ls7a-pch.dtsi
> @@ -199,7 +199,8 @@ gmac@3,0 {
>  					     <13 IRQ_TYPE_LEVEL_HIGH>;
>  				interrupt-names = "macirq", "eth_lpi";
>  				interrupt-parent = <&pic>;
> -				phy-mode = "rgmii";
> +				phy-mode = "rgmii-id";
> +				phy-handle = <&phy0>;
>  				mdio {
>  					#address-cells = <1>;
>  					#size-cells = <0>;
> @@ -222,7 +223,8 @@ gmac@3,1 {
>  					     <15 IRQ_TYPE_LEVEL_HIGH>;
>  				interrupt-names = "macirq", "eth_lpi";
>  				interrupt-parent = <&pic>;
> -				phy-mode = "rgmii";
> +				phy-mode = "rgmii-id";
> +				phy-handle = <&phy1>;
>  				mdio {
>  					#address-cells = <1>;
>  					#size-cells = <0>;
> -- 
> 2.52.0

applied to mips-next
Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]