[mdio] Add MDIO support for "extended" registers as defined by IEEE 802.3 Clause 45.

2015-12-26T17:22:02Z

IEEE 802.3 Clause 45 added backwards-compatible support for 2^16 PHY registers through the addition of an additional device address frame. Clause 45 addressing is used in 10Gbe PHYs, 802.3az EEE registers, etc. It may make sense to provide a similar extension to the miibus interface, but I've refrained from unilaterally doing so here. Submitted by: Landon Fuller Differential Revision: https://reviews.freebsd.org/D4607

[mdio] migrate mdiobus out of etherswitch and into a top-level device of its own.

2015-12-26T02:31:39Z

The mdio driver interface is generally useful for devices that require MDIO without the full MII bus interface. This lifts the driver/interface out of etherswitch(4), and adds a mdio(4) man page. Submitted by: Landon Fuller Differential Revision: https://reviews.freebsd.org/D4606

src-test2/sys/dev/mdio, branch release/11.3.0

[mdio] Add MDIO support for "extended" registers as defined by IEEE 802.3 Clause 45.

[mdio] migrate mdiobus out of etherswitch and into a top-level device of its own.