[PATCH v2 11/12] riscv: dts: starfive: visionfive-v1: Enable gmac and setup phy

[Cristian Ciocaltea]

The StarFive VisionFive V1 SBC has a Motorcomm YT8521 PHY supporting
RGMII-ID, but requires manual adjustment of the RX internal delay to
work properly.

The default RX delay provided by the driver is 1.95 ns, which proves to
be too high. Applying a 50% reduction seems to mitigate the issue.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea at collabora.com>
---
 .../starfive/jh7100-starfive-visionfive-v1.dts  | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/arch/riscv/boot/dts/starfive/jh7100-starfive-visionfive-v1.dts b/arch/riscv/boot/dts/starfive/jh7100-starfive-visionfive-v1.dts
index e82af72f1aaf..e043a27f7612 100644
--- a/arch/riscv/boot/dts/starfive/jh7100-starfive-visionfive-v1.dts
+++ b/arch/riscv/boot/dts/starfive/jh7100-starfive-visionfive-v1.dts
@@ -18,3 +18,20 @@ gpio-restart {
 		priority = <224>;
 	};
 };
+
+&gmac {
+	phy-handle = <&phy>;
+	phy-mode = "rgmii-id";
+	status = "okay";
+
+	mdio {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "snps,dwmac-mdio";
+
+		phy: ethernet-phy at 0 {
+			reg = <0>;
+			rx-internal-delay-ps = <900>;
+		};
+	};
+};
-- 
2.42.0