K 10
svn:author
V 3
jhb
K 8
svn:date
V 27
2018-11-01T21:46:37.367714Z
K 7
svn:log
V 880
Add support for port unit wiring to cxgbe(4).

- Add a bus_child_location_str method to the nexus drivers that prints
  out 'port=N' as the location string exported via devinfo and the
  '%location' sysctl node.

- We can't use a bus_hint_device_unit to wire the unit numbers of
  devices with a fixed devclass as the device gets assigned a unit in
  make_device() before the device creator can set softc, etc.
  Instead, when adding a child device, use a helper function much like
  a bus_hint_device_unit method to look for wiring hints or to return
  -1 to let the system choose a unit number.  This function requires
  an "at" hint for the port pointing to the nexus device and a "port"
  hint listing the port number.  For example:

hint.cxl.4.at="t5nex0"
hint.cxl.4.port="0"

  wires cxl4 to the first port on the t5nex0 adapter.

Requested by:	gallatin
MFC after:	2 months

END