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Subject[PATCH net-next 1/6] ARM: dts: imx6qp-prtwd3: update RGMII delays for sja1105 switch
In the new behavior, the sja1105 driver expects there to be explicit
RGMII delays present on the fixed-link ports, otherwise it will complain
that it falls back to legacy behavior, which is to apply RGMII delays
incorrectly derived from the phy-mode string.

In this case, the legacy behavior of the driver is to apply both RX and
TX delays. To preserve that, add explicit 2 nanosecond delays, which are
identical with what the driver used to add (a 90 degree phase shift).
The delays from the phy-mode are ignored by new kernels (it's still
RGMII as long as it's "rgmii*" something), and the explicit
{rx,tx}-internal-delay-ps properties are ignored by old kernels, so the
change works both ways.

Signed-off-by: Vladimir Oltean <>
arch/arm/boot/dts/imx6qp-prtwd3.dts | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm/boot/dts/imx6qp-prtwd3.dts b/arch/arm/boot/dts/imx6qp-prtwd3.dts
index b92e0f2748a5..29dd59bfa73d 100644
--- a/arch/arm/boot/dts/imx6qp-prtwd3.dts
+++ b/arch/arm/boot/dts/imx6qp-prtwd3.dts
@@ -178,6 +178,8 @@ port@4 {
label = "cpu";
ethernet = <&fec>;
phy-mode = "rgmii-id";
+ rx-internal-delay-ps = <2000>;
+ tx-internal-delay-ps = <2000>;

fixed-link {
speed = <100>;
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