[PATCH v3 10/10] arm64: dts: st: Add I/O sync to eth pinctrl in stm32mp25-pinctrl.dtsi

[Antonio Borneo <antonio.borneo@foss.st.com>]

On board stm32mp257f-ev1, the propagation delay between eth1/eth2
and the external PHY requires a compensation to guarantee that no
packet get lost in all the working conditions.

Add I/O synchronization properties in pinctrl on all the RGMII
data pins, activating re-sampling on both edges of the clock.

Co-developed-by: Christophe Roullier <christophe.roullier@foss.st.com>
Signed-off-by: Christophe Roullier <christophe.roullier@foss.st.com>
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp25-pinctrl.dtsi | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/st/stm32mp25-pinctrl.dtsi b/arch/arm64/boot/dts/st/stm32mp25-pinctrl.dtsi
index e0d102eb61769..7906b3c585a2d 100644
--- a/arch/arm64/boot/dts/st/stm32mp25-pinctrl.dtsi
+++ b/arch/arm64/boot/dts/st/stm32mp25-pinctrl.dtsi
@@ -38,6 +38,7 @@ pins1 {
 			bias-disable;
 			drive-push-pull;
 			slew-rate = <3>;
+			st,io-sync = <4>;
 		};
 		pins2 {
 			pinmux = <STM32_PINMUX('H', 9, AF10)>, /* ETH_RGMII_CLK125 */
@@ -53,6 +54,7 @@ pins3 {
 				 <STM32_PINMUX('H', 13, AF10)>, /* ETH_RGMII_RXD3 */
 				 <STM32_PINMUX('A', 11, AF10)>; /* ETH_RGMII_RX_CTL */
 			bias-disable;
+			st,io-sync = <4>;
 		};
 		pins4 {
 			pinmux = <STM32_PINMUX('A', 14, AF10)>; /* ETH_RGMII_RX_CLK */
@@ -142,6 +144,7 @@ pins1 {
 			bias-disable;
 			drive-push-pull;
 			slew-rate = <3>;
+			st,io-sync = <4>;
 		};
 		pins2 {
 			pinmux = <STM32_PINMUX('F', 8, AF10)>, /* ETH_RGMII_CLK125 */
@@ -164,6 +167,7 @@ pins4 {
 				 <STM32_PINMUX('C', 11, AF10)>, /* ETH_RGMII_RXD3 */
 				 <STM32_PINMUX('C', 3, AF10)>; /* ETH_RGMII_RX_CTL */
 			bias-disable;
+			st,io-sync = <4>;
 		};
 		pins5 {
 			pinmux = <STM32_PINMUX('F', 6, AF10)>; /* ETH_RGMII_RX_CLK */
-- 
2.34.1