Re: [PATCH net-next v4 00/12] Add support for OPEN Alliance 10BASE-T1x MACPHY Serial Interface

From: Andrew Lunn
Date: Fri May 24 2024 - 17:27:46 EST


> In our MDIO functions, we do certain things based on PHY ID, also
> our driver deal with vendor specific register, MMS 12 (refer Table 6
> in section 9.1

That is a bad design. Vendor specific PHY registers should be in MMS 4
which is MMD 31, where the PHY driver can access them. Table 6 says:
"PHY – Vendor Specific" for MMS 4, so clearly that is where the
standards committee expected PHY vendor registers to be.

Anyway, does the PHY driver actually need to access MMS 12? Or can the
MAC driver do it? That is the same question i asked Ramón about the
Microchip part. We really should avoid layering violations as much as
we can, and we should not have the framework make it easy to violate
layering. We want all such horrible hacks hidden in the MAC driver
which needs such horrible hacks because of bad design.

Andrew