Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

MFC: r243857 (partial)

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

MFC r226173, r227843, r227848 and r227908:
Use DEVMETHOD_END to mark end of device methods.
Remove superfluous device methods.
Add some missing __FBSBID() macros.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

- 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@

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

- Hook into the existing stat timer to drive the transmit watchdog instead
of using if_watchdog and if_timer.
- Reorder detach to call ether_ifdetach() before anything else in tl(4)
and wb(4).

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

shutdown returns an int

Call pcn_start_locked() instead of pcn_start() where the softc lock is
already held.

Approved by: rwatson (mentor)
MFC after: 3 weeks

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 pcn driver from sys/pci to sys/dev/pcn.

o break newbus api: add a new argument of type driver_filter_t to
bus_setup_intr()

o add an int return code to all fast handlers

o retire INTR_FAST/IH_FAST

For more info: http://docs.freebsd.org/cgi/getmsg.cgi?fetch=465712+0+current/freebsd-current

Reviewed by: many
Approved by: re@

- Allow multiple (external) PHYs with Am79C97{2,6}, which actually
only support external PHYs (besides not connectable internal ones
which respond at the usual addresses, but which don't hurt if we
let them show up) and don't wedge when isolating PHYs. Actually,
this change special cases limiting PHYs to Am79C97{3,5,8}, for
which this driver doesn't implement swiching between the internal
and external PHYs, yet, and Am79C971, where isolating the external
PHY (at least in case it's a DP83840A) wedges the chip. Together
with sys/dev/mii/acphy.c rev. 1.21 this adds support for the
100baseFX port of AT-2700 series adaptors, which use two AC101,
one for the copper and one for the fibre port (there might be
variants which only use one PHY though).
- Fix a bug in the previous revision that prevented the address of
the used (external) PHY to be actually recorded.
- Don't bother to set if_mtu to ETHERMTU, ether_ifattach() does that.

MFC after: 1 week

- Clear the PCN_MISC_ASEL bit so the media port can be actually set
via the PCN_CSR_MODE register. Along with sys/dev/mii/nsphy.c 1.26
this fixes the case of certain Am79c971-based HP cards and on-board
ones in IBM machines reporting link but not actually passing any
traffic. [1]
- Add support for the internal 10baseT PHY, which actually is used on
at least said HP cards (together with an external DP83840A in a
multiple PHYs configuration). With cards that don't make use of this
internal PHY it'll also show up in FreeBSD but not cause any harm.
This is still missing support for multiple PHYs configuration using
the internal 100baseTX and/or HomePNA PHYs together with external
PHYs or multiple external PHYs though.
- In pcn_ifmedia_upd() call pcn_reset() as otherwise the Am79C971 of
at least said HP cards can wedge when switching from the internal
10baseT PHY to the external PHY. This means that we need to also
initialize and possibly start the chip again in pcn_ifmedia_upd(),
which isn't that bad though as for setting the media port the chip
has to be powered down or stopped anyway and unlike documented
doesn't take effect until the next initialization.

PR: 27995, 25959, 72966 (likely) [1]
MFC after: 2 weeks

- Don't bother to include IDs of PCnet chips which are not supported
by this driver and largely are not even PCI devices in pcn_chipid.
- Use device_printf(9)/if_printf(9) rather than implementing their
functionality with printf(9).
- Sprinkle some const.

Replace references to lnc(4) with references to le(4) (so far the notes
still apply to le(4)) now that lnc(4) is removed and le(4) is going to
replace it.

Do not touch ifp->if_baudrate in miibus aware drivers.

- Store pointer to the link-level address right in "struct ifnet"
rather than in ifindex_table[]; all (except one) accesses are
through ifp anyway. IF_LLADDR() works faster, and all (except
one) ifaddr_byindex() users were converted to use ifp->if_addr.

- Stop storing a (pointer to) Ethernet address in "struct arpcom",
and drop the IFP2ENADDR() macro; all users have been converted
to use IF_LLADDR() instead.

In detach method, move if_free() after bus_teardown_intr().

Fix "struct ifnet" leaks when attach() fails in the middle, e.g.
when mii_phy_probe() or bus_setup_intr() fails. For drivers that
call their detach() in this case, call if_free() there to cover
this case too.

Fix obsolete comment.

MFC After: 2 days

Use callout_init_mtx() to simplify the stats callout.

MFC after: 3 days

Propagate rename of IFF_OACTIVE and IFF_RUNNING to IFF_DRV_OACTIVE and
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.

Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.

Reviewed by: pjd, bz
MFC after: 7 days

Fix up the locking in pcn(4) and mark it MPSAFE.
- Add locked versions of the init() and start() methods.
- Use callout_*() rather than timeout().
- Make the driver lock non-recursive.
- Push down locking in detach() and ioctl().
- Fix the tick routine to bail if the interface has been stopped and use
callout_drain() in detach() after the call to stop().
- Lock the driver lock in the ifmedia handlers.

Tested by: Ketrien I. Saihr-Kesenchedra ketrien at error404.nls.net
MFC after: 1 week

Modify device drivers supporting multicast addresses to lock if_addr_mtx
over iteration of their multicast address lists when synchronizing the
hardware address filter with the network stack-maintained list.

Problem reported by: Ed Maste (emaste at phaedrus dot sandvine dot ca>
MFC after: 1 week

Stop embedding struct ifnet at the top of driver softcs. Instead the
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.

This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.

Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.

Reviewed by: sobomax, sam

Remove bus_{mem,p}io.h and related code for a micro-optimization on i386
and amd64. The optimization is a trivial on recent machines.

Reviewed by: -arch (imp, marcel, dfr)

Invert conditional and use continue to reduce nesting.

Fix style(9) issues with __P removal.

Noticed by: bde

Return BUS_PROBE_DEFAULT instead of 0.

/* -> /*- for license, minor formatting changes

- Simplify pcn_probe() by moving vendor/device matching code to pcn_match().
- Avoid LOR in pcn_probe() by removing useless mutex stuff.

- Move chip ID code into separate function.
- Initialize sc->pcn_type during ATTACH as softc contents may not surivive
from PROBE.
- Print out chip-id to assist with ongoing pcn(4) debugging efforts.

Fix a couple of typos in comments

MFC after: 3 days

Tag a last set of PCI network interfaces as IFF_NEEDSGIANT until they
are either locked down or demonstrated MPSAFE.

Remove burn bridges code that saved/restored the pci config registers
that are now handled in the pci bus layer. They are no longer
necessary.

Replace handrolled CRC calculation with ether_crc32_[lb]e().

Add missing <sys/module.h> includes

Convert callers to the new bus_alloc_resource_any(9) API.

Submitted by: Mark Santcroos <marks@ripe.net>
Reviewed by: imp, dfr, bde

Announce ethernet MAC addresss in ether_ifattach().

Stop setting ifp->if_output to ether_output() since ether_ifattach()
does it for us already.

Don't use caddr_t in mchash(). Also use C99 spellings over BSD ones.

Requested by: bde,imp

Drop the driver lock around calls to if_input to avoid a LOR when
the packets are immediately returned for sending (e.g. when bridging
or packet forwarding). There are more efficient ways to do this
but for now use the least intrusive approach.

Reviewed by: imp, rwatson

Remove duplicate FBSDID's, move others to their right place.

Try to create some sort of consistency in how the routings to find the
multicast hash are written. There are still two distinct algorithms used,
and there actually isn't any reason each driver should have its own copy
of this function as they could all share one copy of it (if it grew an
additional argument).

Replace the if_name and if_unit members of struct ifnet with new members
if_xname, if_dname, and if_dunit. if_xname is the name of the interface
and if_dname/unit are the driver name and instance.

This change paves the way for interface renaming and enhanced pseudo
device creation and configuration symantics.

Approved By: re (in principle)
Reviewed By: njl, imp
Tested On: i386, amd64, sparc64
Obtained From: NetBSD (if_xname)

Prefer new location of pci include files (which have only been in the
tree for two or more years now), except in a few places where there's
code to be compatible with older versions of FreeBSD.

Due to extreme bogusness in the pci bus layer, these drivers were
forced to do slightly bogus power state manipulation. However, this
is one of those features that is preventing further progress, so mark
them as BURN_BIRDGES like I did for the drivers in sys/dev/...

This, like the other change, are a no-op unless you have BURN_BRIDGES
in your kernel.

Remove unused variables.
Remove now unused pointer to ether header.
Remove break after return

Found by: FlexeLint

Use newly minted device_is_attached rather than device_is_alive to see
if attach succeeded. device_is_alive just tells us that probe
succeeded. Since we were using it to do things like detach net
interfaces, this caused problems when there were errors in the attach
routine.

Symptoms of problem reported by: martin blapp

Explicitly declare 'int' parameters.

Revise attach/detach resource cleanup
- Unconditionally call *_stop() if device is in the tree. This is to
prevent callouts from happening after the device is gone. Checks for
bus_child_present() should be added in the future to keep from touching
potentially non-existent hardware in *_detach(). Found by iedowse@.
- Always check for and free miibus children, even if the device is not in
the tree since some failure cases could have gotten here.
- Call ether_ifdetach() in the irq setup failure case
- ti(4), xl(4): move ifmedia_init() calls to the beginning of attach so
that ifmedia_removeall() can be unconditionally called on detach. There
is no way to detect whether ifmedia has been initialized without using
a separate variable (as tl(4) does).
- Add comments to indicate assumptions of code path

Remove another unused variable.

Remove some code that managed to escape from my local repository.

- Don't call pci_enable_io() in drivers (unless needed for resume).
- Don't test memory/port status and emit an error message; the PCI
bus code will do this now.

- Express hard dependencies on bus (pci, isa, pccard) and
network layer (ether).
- Don't abuse module names to facilitate ifconfig module loading;
such abuse isn't really needed. (And if we do need type information
associated with a module then we should make it explicit and not
use hacks.)

Use __FBSDID rather than rcsid[].

Add missing ()'s so that these drivers all compile again.

Noticed by: jake
Tested on: i386 (compile)

Clean up locking and resource management for pci/if_*

- Remove locking of the softc in the attach method, instead depending on
bus_setup_intr being at the end of attach (delaying interrupt enable until
after ether_ifattach is called)
- Call *_detach directly in the error case of attach, depending on checking
in detach to only free resources that were allocated. This puts all
resource freeing in one place, avoiding thinkos that lead to memory leaks.
- Add bus_child_present check to calls to *_stop in the detach method to
be sure hw is present before touching its registers.
- Remove bzero softc calls since device_t should do this for us.
- dc: move interrupt allocation back where it was before. It was unnecessary
to move it. This reverts part of 1.88
- rl: move irq allocation before ether_ifattach. Problems might have been
caused by allocating the irq after enabling interrupts on the card.
- rl: call rl_stop before ether_ifdetach
- sf: call sf_stop before ether_ifdetach
- sis: add missed free of sis_tag
- sis: check errors from tag creation
- sis: move dmamem_alloc and dmamap_load to happen at same time as tag creation
- sk: remove duplicate initialization of sk_dev
- ste: add missed bus_generic_detach
- ti: call ti_stop before ether_ifdetach
- ti: add missed error setting in ti_rdata alloc failure
- vr: add missed error setting in I/O, memory mapping cases
- xl: add missed error setting in I/O, memory mapping cases
- xl: remove multi-level goto on attach failure
- xl: move dmamem_alloc and dmamap_load to happen at same time as tag creation
- Calls to free(9) are unconditional because it is valid to call free with a
null pointer.

Reviewed by: imp, mdodd

Back out M_* changes, per decision of the TRB.

Approved by: trb

Fix an oversight in some code I added to the last commit.

- Remove duplicate call to callout_handle_init() in pcn_attach().
- Conditionalize mtx_destroy() in pcn_attach().
- Assert driver lock in pcn_intr().

Submitted by: Hiten Pandya <hiten@unixdaemons.com>

Turn off interrupts in pcn_stop().

Consolidate resource release code on error condition.

Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.

o track either_ifattach/ether_ifdetach API changes
o use if_input for input packet processing
o don't strip the Ethernet header for input packets
o use BPF_* macros bpf tapping
o call ether_ioctl to handle default ioctl case
o track vlan changes

Reviewed by: many
Approved by: re

style:
put return values on a line by themselves.
fix some paste issues where whitespace was used instead of tabs.

Fix if_timer logic to make sure that there is always a timeout
pending if there are packets queued for transmission.

Several drivers still have the same problem.

MFC after: 3 days

Change callers of mtx_init() to pass in an appropriate lock type name. In
most cases NULL is passed, but in some cases such as network driver locks
(which use the MTX_NETWORK_LOCK macro) and UMA zone locks, a name is used.

Tested on: i386, alpha, sparc64

Remove __P.

Remove printf's on mbuf/cluster allocation failures. There are now
equivalent and less dangerous (rate limited) messages in
the mbuf allocation code.

MFC after: 3 days

Do not call mii_pollstat() from within device tick routines; the status
information is updated by mii_tick().

Pointed out by: wpaul (a while back)

Apply patch supplied by Jonathan Chen: use the correct arguments to
pci_enable_io(). We need to use SYS_RES_IOPORT/SYS_RES_MEMORY instead
of PCIM_CMD_PORTEN/PCIM_CMD_MEMEN.

Fix mindo:

PCN_BCR_CLRBIT(sc, PCN_BCR_MIICTL, PCN_MIICTL_DANAS);

should be:

PCN_BCR_SETBIT(sc, PCN_BCR_MIICTL, PCN_MIICTL_DANAS);

Turning this bit on is what disables MII autoneg, not turning it off.
Without this, manually setting the media doesn't work.

Noticed by: Jim Browne <jbrowne@jbrowne.com>

Workaround to prevent VMware from melting down. The pseudo PCnet interface
in VMware reports 0x00000000 in the PCI subsystem ID register, but
0x10001000 when you read the mirror registers in I/O space. This causes
pcn_probe() to think it's found a card in 32-bit mode, and performing
a 32-bit I/O access makes on a 16-bit port makes VMware go boom. Special
case the 0x10001000 value until somebody at VMware grows a clue.

Finally discovered by: Andrew Gallatin

Big round of minor updates:

- Use pci_get_powerstate()/pci_set_powerstate() in all the other drivers
that need them so we don't have to fiddle with the PCI power management
registers directly.
- Use pci_enable_busmaster()/pci_enable_io() to turn on busmastering and
PIO/memory mapped accesses.
- Add support to the RealTek driver for the D-Link DFE-530TX+ which has
a RealTek 8139 with its own PCI ID. (Submitted by Jason Wright)
- Have the SiS 900/National DP83815 driver be sure to disable PME
mode in sis_reset(). This apparently fixes a problem on some
motherboards where the DP83815 chip fails to receive packets.
(Submitted by Chuck McCrobie <mccrobie@cablespeed.com>)

Convert if_multiaddrs from LIST to TAILQ so that it can be traversed
backwards in the three drivers which want to do that.

Reviewed by: mikeh

Another round of the <sys/queue.h> FOREACH transmogriffer.

Created with: sed(1)
Reviewed by: md5(1)

Use LIST_FOREACH() to traverse ifp->if_multiaddrs list, instead of
<sys/queue.h> implementation details.

Created with: /usr/sbin/sed
Reviewed with: /sbin/md5

Implement MTX_RECURSE flag for mtx_init().
All calls to mtx_init() for mutexes that recurse must now include
the MTX_RECURSE bit in the flag argument variable. This change is in
preparation for an upcoming (further) mutex API cleanup.
The witness code will call panic() if a lock is found to recurse but
the MTX_RECURSE bit was not set during the lock's initialization.

The old MTX_RECURSE "state" bit (in mtx_lock) has been renamed to
MTX_RECURSED, which is more appropriate given its meaning.

The following locks have been made "recursive," thus far:
eventhandler, Giant, callout, sched_lock, possibly some others declared
in the architecture-specific code, all of the network card driver locks
in pci/, as well as some other locks in dev/ stuff that I've found to
be recursive.

Reviewed by: jhb

Initialize/grab the mutex earlier in the attach phase, so that
bailing out to the fail: label where we release/destroy the mutex
will work without exploding.

Update the probe some more to deal with 16/32 bit issues. If the chip
is already in 32-bit mode, we need to be able to detect this and still
read the chip ID code. Detecting 32-bit mode is actually a little
tricky, since we want to avoid turning it on accidentally. The easiest
way to do it is to just try and read the PCI subsystem ID from the
bus control registers using 16-bit accesses and compare that with the
value read from PCI config space. If they match, then we know we're in
16-bit mode, otherwise we assume 32-bit mode.

When checking the device code in the probe routine, leave the chip in
16-bit mode. Technically, pcn_probe() is destructive because once the
chip goes into 32-bit mode, the only way to get it out again is a
hardware reset. And once the device is in 32-bit mode, the lnc driver
won't be able to talk to it. So if pcn_probe() is called before the
lnc probe routine, and pcn_probe() rejects the chip as one it doesn't
support, the lnc driver will be SOL.

I don't like this. I think it's a design flaw that you can't switch
the chip out of 32-bit mode once it's selected. The only 'right'
solution is for the pcn driver to support all of the PCI devices
in 32-bit mode, however I don't have samples of all the PCnet series
cards for testing.

Create a pcn_setfilt() routine that twiddles the promiscuous mode
and nobroadcast bits in the mode register and call it both from
pcn_init() and pcn_ioctl(). Sometimes we need to force the state
of the nobroadcast bit after switching out of promisc mode.

Remove unneeded #include <machine/clock.h>

Use device_get_nameunit(dev) as the mutex string when calling
mtx_init() instead of hard-coded string constant. Also remember to do
the mutex changes to the ste driver, which I forgot in the first commit.

First round of converting network drivers from spls to mutexes. This
takes care of all the 10/100 and gigE PCI drivers that I've done.
Next will be the wireless drivers, then the USB ones. I may pick up
some stragglers along the way. I'm sort of playing this by ear: if
anyone spots any places where I've screwed up horribly, please let me
know.

When leaving suspend mode after enabling/disabling the promisc mode bit,
make sure the chip is restarted by issuing a start command to the command
register. Sometimes the receiver doesn't restart after leaving suspend
mode.

Add the card ID for the Am79c975 PCnet/FAST III card. This is a variant
of the Am79c973 with "AlertIT Technology," whatever that is. Also mention
support for the PCnet/FAST III cards in the documentation. The
PCnet/FAST III chips have integrated 10/100 PHYs.

Add support for the AMD Am79c976 PCnet/PRO controller chip. For now
this just involves adding the chip ID to the supported list: the PCnet/PRO
is compatible with the PCnet/FAST+ and friends and should "just work"
with this driver.

Also try to handle mbuf allocation failures in the receive handler
more gracefully.

Typo in comment (decent performances -> decent performance).

Make pcn_miibus_readreg() latch onto the first PHY that it finds (as
a result of mii_phy_probe()) and use that rather than hardcoding a
constant. The hardcoded way was too specific to the particular card
I had and caused PHY probing to fail on at least one laptop with a
built-in AMD chip.

Reported by: rjk@grauel.com (Richard J Kuhns)

Remove one debug line that snuck in by accident.

Add a new driver for the AMD PCnet/FAST, FAST+ and Home PCI adapters.
Previously, these cards were supported by the lnc driver (and they
still are, but the pcn driver will claim them first), which is fine
except the lnc driver runs them in 16-bit LANCE compatibility mode.
The pcn driver runs these chips in 32-bit mode and uses the RX alignment
feature to achieve zero-copy receive. (Which puts it in the same
class as the xl, fxp and tl chipsets.) This driver is also MI, so it
will work on the x86 and alpha platforms. (The lnc driver is still
needed to support non-PCI cards. At some point, I'll need to newbusify
it so that it too will me MI.)

The Am79c978 HomePNA adapter is also supported.