[PATCH devicetree 3/3] arm64: dts: lx2160abluebox3: update RGMII delays for sja1105 switch

From: Vladimir Oltean
Date: Wed Oct 20 2021 - 07:36:48 EST


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 <vladimir.oltean@xxxxxxx>
---
arch/arm64/boot/dts/freescale/fsl-lx2160a-bluebox3.dts | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/fsl-lx2160a-bluebox3.dts b/arch/arm64/boot/dts/freescale/fsl-lx2160a-bluebox3.dts
index b21be03da0af..042c486bdda2 100644
--- a/arch/arm64/boot/dts/freescale/fsl-lx2160a-bluebox3.dts
+++ b/arch/arm64/boot/dts/freescale/fsl-lx2160a-bluebox3.dts
@@ -386,6 +386,8 @@ port@2 {
reg = <2>;
ethernet = <&dpmac17>;
phy-mode = "rgmii-id";
+ rx-internal-delay-ps = <2000>;
+ tx-internal-delay-ps = <2000>;

fixed-link {
speed = <1000>;
@@ -529,6 +531,8 @@ port@2 {
reg = <2>;
ethernet = <&dpmac18>;
phy-mode = "rgmii-id";
+ rx-internal-delay-ps = <2000>;
+ tx-internal-delay-ps = <2000>;

fixed-link {
speed = <1000>;
--
2.25.1