| Message ID | 20240129114649.2458468-2-u.kleine-koenig@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ARM: dts: stm32: lxa-tac: reduce RGMII interface drive strength | expand |
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
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>;