From: Leonard Göhrs <l.goehrs@pengutronix.de>
Date: Mon, 29 Jan 2024 11:46:49 +0000 (+0100)
Subject: ARM: dts: stm32: lxa-tac: reduce RGMII interface drive strength
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=7fd195f01ae52871b04b752447f865e1a6661487;p=linux.git

ARM: dts: stm32: lxa-tac: reduce RGMII interface drive strength

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>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
---

diff --git a/arch/arm/boot/dts/st/stm32mp15xc-lxa-tac.dtsi b/arch/arm/boot/dts/st/stm32mp15xc-lxa-tac.dtsi
index 7e835a7cf64a5..cfaf8adde319f 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 @@ baseboard_eeprom: &sip_eeprom {
 		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>;