Re: [PATCH 2/2] ARM: bcm2835: dt: Add the ethernet to the device tree

From: Stephen Warren
Date: Wed Feb 03 2016 - 11:11:22 EST


On 02/03/2016 08:02 AM, Lubomir Rintel wrote:
The hub and the ethernet in its port 1 are hardwired on the board.

Compared to the adapters that can be plugged into the USB ports, this
one has no serial EEPROM to store its MAC. Nevertheless, the Raspberry Pi
has the MAC address for this adapter in its ROM, accessible from its
firmware.

U-Boot can read out the address and set the local-mac-address property of the
node with "ethernet" alias. Let's add the node so that U-Boot can do its
business.

Good to see we're getting a standard for this.

Have you talked to the RPi Foundation about updating their binary bootloader to follow this protocol? I'll certainly ack changes to make this work for U-Boot, provided the USB core patch this relies upon is accepted.

diff --git a/arch/arm/boot/dts/bcm2835-rpi-b-plus.dts b/arch/arm/boot/dts/bcm2835-rpi-b-plus.dts

+&usb {
+ usb1@01 {
+ compatible = "usb1d6b,0002";
+ reg = <01>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ethernet: usbether@01 {
+ compatible = "usb0424,9514";
+ reg = <01>;

Ib both unit addresses and both reg properties, I would expect "1" not "01" since there's usually no leading 0 fill for those.

I'm curious why the VID values for the hub and Ethernet device don't match since those are part of the same combo chip. Is there a typo there, or did SMSC really do something odd in HW?