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

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

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags in sys/dev.

Remove duplicate const specifiers in many drivers (I hope I got all of
them, please let me know if not). Most of these are of the form:

static const struct bzzt_type {
[...list of members...]
} const bzzt_devs[] = {
[...list of initializers...]
};

The second const is unnecessary, as arrays cannot be modified anyway,
and if the elements are const, the whole thing is const automatically
(e.g. it is placed in .rodata).

I have verified this does not change the binary output of a full kernel
build (except for build timestamps embedded in the object files).

Reviewed by: yongari, marius
MFC after: 1 week

- There's no need to overwrite the default device method with the default
one. Interestingly, these are actually the default for quite some time
(bus_generic_driver_added(9) since r52045 and bus_generic_print_child(9)
since r52045) but even recently added device drivers do this unnecessarily.
Discussed with: jhb, marcel
- While at it, use DEVMETHOD_END.
Discussed with: jhb
- Also while at it, use __FBSDID.

- Import the common MII bitbang'ing code from NetBSD and convert drivers to
take advantage of it instead of duplicating it. This reduces the size of
the i386 GENERIC kernel by about 4k. The only potential in-tree user left
unconverted is xe(4), which generally should be changed to use miibus(4)
instead of implementing PHY handling on its own, as otherwise it makes not
much sense to add a dependency on miibus(4)/mii_bitbang(4) to xe(4) just
for the MII bitbang'ing code. The common MII bitbang'ing code also is
useful in the embedded space for using GPIO pins to implement MII access.
- Based on lessons learnt with dc(4) (see r185750), add bus barriers to the
MII bitbang read and write functions of the other drivers converted in
order to ensure the intended ordering. Given that register access via an
index register as well as register bank/window switching is subject to the
same problem, also add bus barriers to the respective functions of smc(4),
tl(4) and xl(4).
- Sprinkle some const.

Thanks to the following testers:
Andrew Bliznak (nge(4)), nwhitehorn@ (bm(4)), yongari@ (sis(4) and ste(4))
Thanks to Hans-Joerg Sirtl for supplying hardware to test stge(4).

Reviewed by: yongari (subset of drivers)
Obtained from: NetBSD (partially)

- Remove attempts to implement setting of BMCR_LOOP/MIIF_NOLOOP
(reporting IFM_LOOP based on BMCR_LOOP is left in place though as
it might provide useful for debugging). For most mii(4) drivers it
was unclear whether the PHYs driven by them actually support
loopback or not. Moreover, typically loopback mode also needs to
be activated on the MAC, which none of the Ethernet drivers using
mii(4) implements. Given that loopback media has no real use (and
obviously hardly had a chance to actually work) besides for driver
development (which just loopback mode should be sufficient for
though, i.e one doesn't necessary need support for loopback media)
support for it is just dropped as both NetBSD and OpenBSD already
did quite some time ago.
- Let mii_phy_add_media() also announce the support of IFM_NONE.
- Restructure the PHY entry points to use a structure of entry points
instead of discrete function pointers, and extend this to include
a "reset" entry point. Make sure any PHY-specific reset routine is
always used, and provide one for lxtphy(4) which disables MII
interrupts (as is done for a few other PHYs we have drivers for).
This includes changing NIC drivers which previously just called the
generic mii_phy_reset() to now actually call the PHY-specific reset
routine, which might be crucial in some cases. While at it, the
redundant checks in these NIC drivers for mii->mii_instance not being
zero before calling the reset routines were removed because as soon
as one PHY driver attaches mii->mii_instance is incremented and we
hardly can end up in their media change callbacks etc if no PHY driver
has attached as mii_attach() would have failed in that case and not
attach a miibus(4) instance.
Consequently, NIC drivers now no longer should call mii_phy_reset()
directly, so it was removed from EXPORT_SYMS.
- Add a mii_phy_dev_attach() as a companion helper to mii_phy_dev_probe().
The purpose of that function is to perform the common steps to attach
a PHY driver instance and to hook it up to the miibus(4) instance and to
optionally also handle the probing, addition and initialization of the
supported media. So all a PHY driver without any special requirements
has to do in its bus attach method is to call mii_phy_dev_attach()
along with PHY-specific MIIF_* flags, a pointer to its PHY functions
and the add_media set to one. All PHY drivers were updated to take
advantage of mii_phy_dev_attach() as appropriate. Along with these
changes the capability mask was added to the mii_softc structure so
PHY drivers taking advantage of mii_phy_dev_attach() but still
handling media on their own do not need to fiddle with the MII attach
arguments anyway.
- Keep track of the PHY offset in the mii_softc structure. This is done
for compatibility with NetBSD/OpenBSD.
- Keep track of the PHY's OUI, model and revision in the mii_softc
structure. Several PHY drivers require this information also after
attaching and previously had to wrap their own softc around mii_softc.
NetBSD/OpenBSD also keep track of the model and revision on their
mii_softc structure. All PHY drivers were updated to take advantage
as appropriate.
- Convert the mebers of the MII data structure to unsigned where
appropriate. This is partly inspired by NetBSD/OpenBSD.
- According to IEEE 802.3-2002 the bits actually have to be reversed
when mapping an OUI to the MII ID registers. All PHY drivers and
miidevs where changed as necessary. Actually this now again allows to
largely share miidevs with NetBSD, which fixed this problem already
9 years ago. Consequently miidevs was synced as far as possible.
- Add MIIF_NOMANPAUSE and mii_phy_flowstatus() calls to drivers that
weren't explicitly converted to support flow control before. It's
unclear whether flow control actually works with these but typically
it should and their net behavior should be more correct with these
changes in place than without if the MAC driver sets MIIF_DOPAUSE.

Obtained from: NetBSD (partially)
Reviewed by: yongari (earlier version), silence on arch@ and net@

Do a sweep of the tree replacing calls to pci_find_extcap() with calls to
pci_find_cap() instead.

sysctl(9) cleanup checkpoint: amd64 GENERIC builds cleanly.

Commit the rest of the devices.

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

It seems some old Sundace(now IC Plus Corp.) controllers do not
like memory mapped register access. Typical problem from the issue
was MII access returned unreliable values. I'm not sure this comes
from lack of register flushing in MII access after accessing
STE_PHYCTL register though.
To address the issue, read hints data that controls which type of
memory mapping should be used in driver. ste(4) still prefers
memory mapping to io mapping but honor hints entered by user except
for controllers that have problems with memory mapping.
The hint to use iomapping could be given by adding the following
line to /boot/device.hints file.

hint.ste.0.prefer_iomap="1"

PR: kern/149285
MFC after: 5 days

Make sure to store dma address of RX buffer in little endian form.
This fixes the last bug which keeps ste(4) from working on sparc64.

Fix EEPROM access code to return data in host byte order.
EEPROM on ST201 always returns 16bits data with little endian
format so conversion to host order is required.
This change fixes inversed ethernet address on sparc64.

Remove extraneous semicolons, no functional changes.

Submitted by: Marc Balmer <marc@msys.ch>
MFC after: 1 week

ether_ifattach sets if_mtu, remove unnecessary code.

Update if_iqdrops in case of RX buffer allocation failure.

Add suspend/resume support as well as basic WOL.
While I'm here simplify SIOCSIFCAP handler.

Implement RX interrupt moderation using one-shot timer interrupt.
Unlike TX interrupt, ST201 does not provide any mechanism to
suppress RX interrupts. ste(4) can generate more than 70k RX
interrupts under heavy RX traffics such that these excessive
interrupts make system useless to process other useful things.
Maybe this was the major reason why polling support code was
introduced to ste(4).
The STE_COUNTDOWN register provides a programmable counter that
will generate an interrupt upon its expiration. We program
STE_DMACTL register to use 3.2us clock rate to drive the counter
register. Whenever ste(4) serves RX interrupt, the driver rearm
the timer to expire after STE_IM_RX_TIMER_DEFAULT time and disables
further generation of RX interrupts. This trick seems to work well
and ste(4) generates less than 8k RX interrupts even under 64 bytes
UDP torture test. Combined with TX interrupts, the total number of
interrupts are less than 10k which looks reasonable on heavily
loaded controller.

The default RX interrupt moderation time is 150us. Users can change
the value at any time with dev.ste.%d.int_rx_mod sysctl node.
Setting it 0 effectively disables the RX interrupt moderation
feature. Now we have both TX/RX interrupt moderation code so remove
loop of interrupt handler which resulted in sub-optimal performance
as well as more register accesses.

We don't need to generate DMA complete interrupt for every
transmitted frames. So request interrupt for every 16th frames. Due
to the limitation of hardware we can't suppress the interrupt as
driver should have to check TX status register. The TX status
register can store up to 31 TX status so driver can't send more
than 31 frames without reading TX status register.
With this change controller would not generate TX completion
interrupt for every frame, so reclaim transmitted frames in
ste_tick().

Correct STE_COUNTDOWN register offset. The datasheet was wrong.

Remove unused duplicated register definition. It seems the
definition was made to access STE_ASICCTL register as 16bits but
ste(4) always access the register as 32bits so it was never used
before.

Implement hardware MAC statistics counter support. The counters
could be accessed with dev.ste.0.stats sysctl node.

Report the correct result of mii_mediachg(). Previously it always
used to return success without respect to the result.
While I'm here use mii_mediachg() in ste_init_locked which allows
driver to use currently configured media. ste_ifmedia_upd() is
supposed to be called whenever user changes current media settings.

Don't report link status if driver is not running.

Overhaul RX filter programming.
o Let RX filter handler program promiscuous/multicast filter as
well as broadcasting.
o Remove unnecessary register access.
o Simplify ioctl handler and have set_rxfilter to handle
IFF_PROMISC and IFF_ALLMULTI change instead of directly
programming the controller.
o Removed unnecessary error variable reinitialization in ioctl
handler.
o Add IFF_DRV_RUNNING check before programming multicast filter.
o Configure maximum allowed frame length before enabling MAC.
Datasheet didn't say the exact ordering of programming sequence
but it looks more natural to set maximum allowed frame length
first prior to enabling controller.

Reimplement controller reset. Datasheet says full reset takes about
1ms. Since we switched to memory register mapping make sure to
flush PCI posted write by reading the register again.
While I'm here add additional delays in loop while driver waits the
completion of the reset.

Don't reinitialize controller if driver is already running. This
reduces number of link state UP/DOWN changes.

Reimplement Tx status error handler as recommended by datasheet.
If ste(4) encounter TX underrun or excessive collisions the TX MAC
of controller is stalled so driver should wake it up again. TX
underrun requires increasing TX threshold value to minimize
further TX underruns. Previously ste(4) used to reset controller
to recover from TX underrun, excessive collision and reclaiming
error. However datasheet says only TX underrun requires resetting
entire controller. So implement ste_restart_tx() that restarts TX
MAC and do not perform full reset except TX underrun case.
Now ste(4) uses CSR_READ_2 instead of CSR_READ_1 to read
STE_TX_STATUS register. This way ste(4) will also read frame id
value and we can write the same value back to STE_TX_FRAMEID
register instead of overwriting it to 0. The datasheet was wrong
in write back of STE_TX_STATUS so add some comments why we do so.
Also always invoke ste_txeoc() after ste_txeof() in ste_poll as
without reading TX status register can stall TX MAC.

Prefer bus_write_{1,2,4}/bus_read_{1,2,4} to
bus_space_write_{1,2,4}/bus_space_read_{1,2,4}.
Remove unused ste_bhandle and ste_btag in softc.

Prefer memory space register mapping over io space. If memory space
mapping fails fall back to old io space mapping.
While I'm here use PCIR_BAR macro.

Instead of relying on hard resetting of controller to stop
receiving incoming traffics, try harder to gracefully stop active
DMA cycles and then stop MACs. This is the way what datasheet
recommends and seems to work reliably. Resetting controller while
active DMAs are in progress is bad thing as we can't predict how
DMAs touche allocated TX/RX buffers. This change ensures controller
stop state before attempting to release allocated TX/RX buffers.
Also update MAC statistics which could have been updated during the
wait time of MAC stop.

While I'm here remove unnecessary controller resets in various
location. ste(4) no longer relies on hard controller reset to stop
controller and resetting controller also clears all configured
settings which makes it hard to implement WOL in near future.
Now resetting a controller is performed in ste_init_locked().

Reimplement miibus_statchg method. Don't rely on link state change
interrupt. If we want to use link state change interrupt ste(4)
should also implement auto-negotiation complete handler as well as
various PHY access handling. Now link state change is handled by
mii(4) polling so it will automatically update link state UP/DOWN
events which in turn make ste(4) usable with lagg(4).

r199559 added a private timer to drive watchdog and the timer also
used to drive MAC statistics update. Because the MAC statistics
update is called whenever statistics counter reaches near-full, it
drove watchdog timer too fast such that it caused false watchdog
timeouts under heavy TX traffic conditions.
Fix the regression by separating ste_stats_update() from driving
watchdog timer and introduce a new function ste_tick() that handles
periodic job such as driving watchdog, MAC statistics update and
link state check etc.
While I'm here clear armed watchdog timer in ste_stop().

Introduce sc_flags member variable and use it to keep track of
link state and PHY related information.
Remove ste_link and ste_one_phy variable of softc as it's not used
anymore.
While I'm here add IFF_DRV_RUNNING check in ste_start_locked().

Add minimal dealy while ste(4) is waiting for the end of active DMA
cycle.

Add bus_dma(9) and endianness support to ste(4).
o Sorted includes and added missing header files.
o Added basic endianness support. In theory ste(4) should work on
any architectures.
o Remove the use of contigmalloc(9), contigfree(9) and vtophys(9).
o Added 8 byte alignment limitation of TX/RX descriptor.
o Added 1 byte alignment requirement for TX/RX buffers.
o ste(4) controllers does not support DAC. Limit DMA address space
to be within 32bit address.
o Added spare DMA map to gracefully recover from DMA map failure.
o Removed dead code for checking STE_RXSTAT_DMADONE bit. The bit
was already checked in each iteration of loop so it can't be true.
o Added second argument count to ste_rxeof(). It is used to limit
number of iterations done in RX handler. ATM polling is the only
consumer.
o Removed ste_rxeoc() which was added to address RX stuck issue
(cvs rev 1.66). Unlike TX descriptors, ST201 supports chaining
descriptors to form a ring for RX descriptors. If RX descriptor
chaining is not supported it's possible for controller to stop
receiving incoming frames once controller pass the end of RX
descriptor which in turn requires driver post new RX
descriptors to receive more frames. For TX descriptors which
does not support chaning, we exactly do manual chaining in
driver by concatenating new descriptors to the end of previous
TX chain.
Maybe the workaround was borrowed from other drivers that does
not support RX descriptor chaining, which is not valid for ST201
controllers. I still have no idea how this address RX stuck
issue and I can't reproduce the RX stuck issue on DFE-550TX
controller.
o Removed hw.ste_rxsyncs sysctl as the workaround was removed.
o TX/RX side bus_dmamap_load_mbuf_sg(9) support.
o Reimplemented optimized ste_encap().
o Simplified TX logic of ste_start_locked().
o Added comments for TFD/RFD requirements.
o Increased number of RX descriptors to 128 from 64. 128 gave much
better performance than 64 under high network loads.

Sort function prototyes.

style(9)

Remove trailing white spaces.

s/u_intXX_t/uintXX_t/g

o Remove unnecessary return statement.
o Remove register keyword.

Use ANSI function definations.

- Add a private timer to drive the transmit watchdog instead of using
if_watchdog and if_timer.
- Fix some issues in detach for sn(4), ste(4), and ti(4). Primarily this
means calling ether_ifdetach() before anything else.

Use if_maddr_rlock()/if_maddr_runlock() rather than IF_ADDR_LOCK()/
IF_ADDR_UNLOCK() across network device drivers when accessing the
per-interface multicast address list, if_multiaddrs. This will
allow us to change the locking strategy without affecting our driver
programming interface or binary interface.

For two wireless drivers, remove unnecessary locking, since they
don't actually access the multicast address list.

Approved by: re (kib)
MFC after: 6 weeks

When user_frac in the polling subsystem is low it is going to busy the
CPU for too long period than necessary. Additively, interfaces are kept
polled (in the tick) even if no more packets are available.
In order to avoid such situations a new generic mechanism can be
implemented in proactive way, keeping track of the time spent on any
packet and fragmenting the time for any tick, stopping the processing
as soon as possible.

In order to implement such mechanism, the polling handler needs to
change, returning the number of packets processed.
While the intended logic is not part of this patch, the polling KPI is
broken by this commit, adding an int return value and the new flag
IFCAP_POLLING_NOCOUNT (which will signal that the return value is
meaningless for the installed handler and checking should be skipped).

Bump __FreeBSD_version in order to signal such situation.

Reviewed by: emaste
Sponsored by: Sandvine Incorporated

Clean out some empty mergeinfo records, presumably by people doing local
cp/mv operations. The full repo-relative URL should be specified for the
source in these cases.

Move the ste driver from sys/pci to sys/dev/ste.