- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

- Correct mispellings of the word necessary

Submitted by: Christoph Mallon <christoph.mallon@gmx.de> (via private mail)

Partially merge r223648, r223648 and r223949 from gem(4):
- Consistently use the newly introduced sc_mac_rxcfg throughout the driver
instead of reading the old content of CAS_MAC_RX_CONF.
- Increment if_iqdrops instead of if_ierrors in case of RX buffer allocation
failure.
- According to the Cassini datasheet the RX MAC should also be disabled in
cas_setladrf() before changing its configuration.
- Add error messages to gem_disable_{r,t}x() and take advantage of these
throughout the driver instead of duplicating their functionality all over
the place.

Convert the PHY drivers to honor the mii_flags passed down and convert
the NIC drivers as well as the PHY drivers to take advantage of the
mii_attach() introduced in r213878 to get rid of certain hacks. For
the most part these were:
- Artificially limiting miibus_{read,write}reg methods to certain PHY
addresses; we now let mii_attach() only probe the PHY at the desired
address(es) instead.
- PHY drivers setting MIIF_* flags based on the NIC driver they hang
off from, partly even based on grabbing and using the softc of the
parent; we now pass these flags down from the NIC to the PHY drivers
via mii_attach(). This got us rid of all such hacks except those of
brgphy() in combination with bce(4) and bge(4), which is way beyond
what can be expressed with simple flags.

While at it, I took the opportunity to change the NIC drivers to pass
up the error returned by mii_attach() (previously by mii_phy_probe())
and unify the error message used in this case where and as appropriate
as mii_attach() actually can fail for a number of reasons, not just
because of no PHY(s) being present at the expected address(es).

Reviewed by: jhb, yongari

- Change this driver to do taskqueue(9) based TX and interrupt
handling in order to reduce interrupt overhead which results in
better performance.
- Call ether_ifdetach(9) before stopping the controller and the
callouts detach in order to prevent active BPF listeners to clear
promiscuous mode which may lead to the tick callout being restarted
which will trigger a panic once it's actually gone.
- Add explicit IFF_DRV_RUNNING checking in order to prevent extra
link up/down events when using dhclient(8).
- Use the correct macro for deciding whether 2/3 of the available TX
descriptors are used.
- Wrap the RX fault printing in #ifdef CAS_DEBUG in order to not
unnecessarily frighten users and as debugging was the actual
intention. Real errors caused by these faults still will be
accumulated as input errors. It might be a good idea to later on
add driver specific counters for the faults though.

Submitted by: yongari (original patch)

Add cas(4), a driver for Sun Cassini/Cassini+ and National Semiconductor
DP83065 Saturn Gigabit Ethernet controllers. These are the successors
of the Sun GEM controllers and still have a similar but extended transmit
logic. As such this driver is based on gem(4).
Thanks to marcel@ for providing a Sun Quad GigaSwift Ethernet UTP (QGE)
card which was vital for getting this driver to work on architectures
not using Open Firmware.

Approved by: re (kib)
MFC after: 2 weeks