[PATCH 1/4] ARM: dts: imx6qdl-sabrelite: add mdio phy address 0

Francesco Dolcini francesco at dolcini.it
Tue May 12 00:51:20 PDT 2026


On Mon, May 11, 2026 at 05:04:56PM -0400, Frank Li wrote:
> According to IEEE 802.3 Clause 22.2.4.5.5 PHYAD (PHY Address), A PHY that
> is connected to the station management entity via the mechanical interface
> defined in 22.6 shall always respond to transactions addressed to PHY
> Address zero <00000>.
> 
> Use address 0 is safe because only one MDIO phy under mdio bus.

I do not think this is generally safe.

Not all ethernet phy answer to the 0 broadcast address. The one that I
have personally worked with consider 0 a unicast address.

Francesco




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