Add e6000sw driver supporting Marvell 88E6352, 88E6172, 88E6176 switches.
It needs to be attached to mdio interface, exporting SMI access
functionality. e6000sw supports port-based VLAN configuration, per-port
media changing, accessing PHY and switch registers.
e6000sw attaches miibuses and PHY drivers as children. Instead of typical
tick as callout, kthread-based tick is used. This combined with SX locks
allows MDIO read/write calls to sleep. It is expected, because this
hardware requires long delays in SMI read/write procedures, which can not
be handled by busy-waiting.
Reviewed by: adrian
Obtained from: Semihalf
Submitted by: Bartosz Szczepanek <bsz@semihalf.com>
Differential revision: https://reviews.freebsd.org/D3902
5420071d39