Re: [PATCH] ARM: dts: stm32: lxa-tac: reduce RGMII interface drive strength

[Alexandre TORGUE <alexandre.torgue@foss.st.com>]

Hi

On 1/29/24 12:46, Uwe Kleine-König wrote:
> From: Leonard Göhrs <l.goehrs@pengutronix.de>
> 
> This results in an improvement of EMI performance by reducing the
> 125MHz emission and its harmonics caused by the RGMII clock line.
> 
> Signed-off-by: Leonard Göhrs <l.goehrs@pengutronix.de>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
>   arch/arm/boot/dts/st/stm32mp15xc-lxa-tac.dtsi | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/st/stm32mp15xc-lxa-tac.dtsi b/arch/arm/boot/dts/st/stm32mp15xc-lxa-tac.dtsi
> index 7e835a7cf64a..cfaf8adde319 100644
> --- a/arch/arm/boot/dts/st/stm32mp15xc-lxa-tac.dtsi
> +++ b/arch/arm/boot/dts/st/stm32mp15xc-lxa-tac.dtsi
> @@ -471,6 +471,10 @@ switch: switch@0 {
>   		interrupt-parent = <&gpioa>;
>   		interrupts = <6 IRQ_TYPE_EDGE_RISING>;
>   
> +		/* Reduce RGMII EMI emissions by reducing drive strength */
> +		microchip,hi-drive-strength-microamp = <2000>;
> +		microchip,lo-drive-strength-microamp = <8000>;
> +
>   		ports {
>   			#address-cells = <1>;
>   			#size-cells = <0>;

Applied on stm32-next.

Thanks
Alex