Ethernet not coming up on boot

Struggled working this for a few hours now, hoping for some insight into how I might be able to address. I have a custom carrier with the ethernet wired up the same as the stock carrier design. As expected the ethernet port works with the DTS defined in the p2888/p2822 dtsi files… However I am having an odd issue I cannot understand assuming it rooted in something separate from the phy0/2490000 device definition… When booting the box the ethernet port is showing no carrier, if I unplug and plug the interface back in everything comes up and all is well, if I keep unplugging and plugging it back in, every other plug in the interface comes back up…

If I use mii-tool to check I get “no link” either, again at every other plug event it is good… Since I did not touch the ethernet DTS related items I am at a bit of a loss here, not sure how to approach troubleshooting in more detail.


Are there any differences on Ethernet with P2822 desgin?
Are you using same 88E1512PB2 phy?

That made me realize you were right, we are using the KSZ9031RNXIA. In reading the forums it seems I am not the only one with this specific issue with this PHY, not sure how to approach at the moment. Made the change and the phy is being recognized, however it has the same issue…

phy0: ethernet-phy@0 {
			//compatible = "ethernet-phy-ieee802.3-c22";
			compatible = "micrel,ksz9031";
			reg = <0>;
			interrupt-parent = <&tegra_main_gpio>;
			interrupts = <TEGRA194_MAIN_GPIO(G, 4) IRQ_TYPE_LEVEL_LOW>;
			/* Setup LED[2] as interrupt pin (active low) */
			//marvell,reg-init = <0x03 0x12 0x7fff 0x880>;

Please tell that in the beginning because that is totally not same as stock carrier board design…

Are you able to see the mdio bus driver on device?

Please check this topic.

That was my mistake, I was under the impression it was…

In any case the manufacturer of the PHY confirmed a bug exists in the PHY… I applied a patch to the phy_driver.c file per an errata they have listed, which was posted to another thread on the same topic…

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