[PATCH 1/4] arm64: dts: ti: k3-am642-{evm,sk}: add ti,min-output-impedance

[Siddharth Vadapalli]

The default impedance for the MAC I/O lines from the DP83867 Ethernet PHY
is 50 Ohm. Based on the board PCB traces, this impedance is relatively
higher than expected, resulting in CRC errors for packets being transmitted
and received. Hence, add the "ti,min-output-impedance" device-tree property
to set the impedance to its lowest possible value of 35 Ohm as described in
the DP83867 Datasheet [0].

[0]: https://www.ti.com/lit/ds/symlink/dp83867e.pdf

Signed-off-by: Siddharth Vadapalli <s-vadapalli at ti.com>
---
 arch/arm64/boot/dts/ti/k3-am642-evm.dts | 1 +
 arch/arm64/boot/dts/ti/k3-am642-sk.dts  | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/arch/arm64/boot/dts/ti/k3-am642-evm.dts b/arch/arm64/boot/dts/ti/k3-am642-evm.dts
index 88093ab74502..bc4347cf7114 100644
--- a/arch/arm64/boot/dts/ti/k3-am642-evm.dts
+++ b/arch/arm64/boot/dts/ti/k3-am642-evm.dts
@@ -601,6 +601,7 @@ cpsw3g_phy0: ethernet-phy at 0 {
 		reg = <0>;
 		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_00_NS>;
 		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
+		ti,min-output-impedance;
 	};
 };
 
diff --git a/arch/arm64/boot/dts/ti/k3-am642-sk.dts b/arch/arm64/boot/dts/ti/k3-am642-sk.dts
index 34bfa99bd4b8..d28a38c87f32 100644
--- a/arch/arm64/boot/dts/ti/k3-am642-sk.dts
+++ b/arch/arm64/boot/dts/ti/k3-am642-sk.dts
@@ -519,12 +519,14 @@ cpsw3g_phy0: ethernet-phy at 0 {
 		reg = <0>;
 		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_00_NS>;
 		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
+		ti,min-output-impedance;
 	};
 
 	cpsw3g_phy1: ethernet-phy at 1 {
 		reg = <1>;
 		ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_00_NS>;
 		ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
+		ti,min-output-impedance;
 	};
 };
 
-- 
2.51.1