With FBS enabled, we have no idea what command caused timeout.
Implement same logic as in siis(4) - wait for other commands
complete or timeout and then give some more time.
- introduce drbr_needs_enqueue that returns whether the interface/br needs
an enqueue operation: returns true if altq is enabled or there are
already packets in the ring (as we need to maintain packet order)
- update all drbr consumers
- fix drbr_flush
- avoid using the driver queue (IFQ_DRV_*) in the altq case as the
multiqueue consumer does not provide enough protection, serialize altq
interaction with the main queue lock
- make drbr_dequeue_cond work with altq
Discussed with: kmacy, yongari, jfv
MFC after: 4 weeks
It is belived that that pass s not needed anymore.
Specifically it is not required now for the reasons that were given
in the removed comment.
Discussed with: jhb
MFC after: 4 weeks
Some current systems dynamically load SSDT(s) when _PDC/_OSC method
of Processor is evaluated. Other devices in ACPI namespace may access
objects defined in the dynamic SSDT. Drivers for such devices might
have to have a rather high priority, because of other dependencies.
Good example is acpi_ec driver for EC.
Thus we attach to Processors as early as possible to load the SSDTs
before any other drivers may try to evaluate control methods.
It also seems to be a natural order for a processor in a device
hierarchy.
On the other hand, some child devices on acpi cpu bus need to access
other system resources like PCI configuration space of chipset devices,
so they need to be probed and attached rather late.
For this reason we probe and attach the cpu bus at
SI_SUB_CONFIGURE:SI_ORDER_MIDDLE SYSINIT level.
In the future this could be done more elegantly via multipass.
Please note that acpi drivers that might access ACPI namespace from
device_identify will do that before _PDC/_OSC of Processors are evaluated.
Legacy cpu driver is not affected by this change.
PR: kern/142561 (in part)
Reviewed by: jhb
Silence from: acpi@
MFC after: 5 weeks
The softc obtained in device probe wouldn't be the same one used in
device attach. Drivers should not assume any values stored in softc
structure in probe routine will be available for its attach routine.
brightness, wired LAN power and bass gain), and update the description of
one previously unknown feature (display contrast). While here, expand on
a comment and remove two defines left over from an old version of the code.
Also update man page to document the above changes, and correct grammar.
PR: kern/127581
_PDC was deprecated in favor of _OSC long time ago, but it
seems that they still peacefully coexist and in some case
only _PDC is present.
Still _OSC provides a reacher interface and is capable to
report back its status.
If the status is non-zero, then report it, we may find
it useful to understand what firmware expects from OS.
Also clean up some comments that became less useful over time.
Reviewed by: njl, jhb, rpaulo
MFC after: 3 weeks
numbers and handle types in rational way. This will better protect from
(unwittingly) dealing with stale handles/commands.
Fix the watchdog timeout code to better protect itself from mistakes.
If we run an abort on a putatively timed out command, the command
may in fact get completed, so check to make sure the command we're
timing it out is still around. If the abort succeeds, btw, the command
should get returned via a different path.
TNT5004 IC. This involved a major rewrite of a number of things, as
this chip no longer supports the NAT7210 legacy mode but requires the
host to use the (more modern) FIFO mode.
In theory, this also ought to work on the older TNT4882C chip. I'll
probably add this as optional support (perhaps by a device.hints flag)
later on. By now, FIFO mode is *only* activates iff a TNT5004 chip
has been detected (where the old code didn't work at all), while
everything else is supposed to use the old code.
MFC after: 2 weeks
no effect. Make sure to clear error bits by writing 1. [1]
While I'm here use predefined value instead of hardcodig magic
vlaue.
Submitted by: msaitoh at NetBSD [1]
lagg and vlan the vlan attach/detach event is not being
handed down to em, this caused some init code not to run,
and thus VLANs did not work. Ultimately having the event
get propagated would be nice, but for now the solution is
to have HWFILTER off by default, when this is the case
VLANs will work, ifconfig can be used to turn it on and
then get HW tag filtering.
available today.
This card is a low power 802.11bgn that only does 11n rates up to MCS 7
(that's 65 Mbps in 20Mhz mode and 135 in 40Mhz mode).
802.11n is not yet supported, but will be in the future.
The driver still has a problem regarding to the setting of txpower on
the card, so don't expect good performance yet. After fixing this
problem, an MFC is possible.
Special thanks to iXsystems and S Smirnov <tonve at yandex.ru> for help
with the purchase of a netbook with this card.
Sponsored by: iXsystems, Inc.
- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.
format is higher than 6-bit instead of relying VGA compatibility flag.
This fixes palette problem of NVIDIA GeForce 6600. Reduce code differences
between palette load/save functions while we are here.
Tested by: danfe
Also, account for a quirk of AMD/ATI HPET which reports number of timers
instead of id of the last timer as manadated by the specification.
Currently this has no effect on functionality but in the future we may
make actual use of the HPET timers, not only of its timecounter.
MFC after: 2 weeks
igb now has a queue notion that has a single interrupt
with an RX/TX pair, this will reduce the total interrupts
seen on a system. Both em and igb have a new watchdog
method. igb has fixes from Pyun Yong-Hyeon that have
improved stability, thank you :)
I wish to MFC this for 7.3 asap, please test if able.
Limit early revisions from 6Gb/s to 3Gb/s by default, or they negotiate
only 1.5Gbps, when 3Gb/s devices connected.
Add dummy driver for PATA part of these controllers, preventing generic
driver attach them. It causes system freeze when SATA controller used after
PATA was touched.
the intention of having two ttys pointing to the same cfe console device was.
Also we were not initializing the output[] array passed in as input to
tty_makedev() so one name of the ttys was garbage.
Fix the code that calls cfe_write() to deal with the case where only a partial
buffer is written out.
cfe_cngetc() needs to return if there is no character available as input.
If we don't do this then the cfe_timeout() function will spin forever
because cfe_cngetc() will only ever return if there is valid input.
Approved by: imp (mentor)
frontend uses the same uPD7210 backend as the pcii ISA frontend, so
the backend has to cope with both situations.
Also, hide the first printf in pcii_probe (address mismatch) behind
bootverbose as the ISA bus parent tries to probe all configured ISA
devices against each driver, so a the console has been cluttered with
this message for a bunch of unrelated driver probes.
MFC after: 3 days
. Properly allocate all IO space resources. These cards scatter their
IO addresses over a range of 0x1600 bytes, and they require an
additional address for "special interrupt handling".
. Implement the "special interrupt handling" per the GPIB-PCIIA
Technical Reference Manual; this was apparently not declared for the
clone card this driver has been originally implemented for, but it
turned out to be needed for both, an original NI brand PCII/PCIIA
card as well as the Axiom AX5488 clone.
. Add some diagnostic messages for various resource allocation etc.
failures during probe.
. Add some comments about the structure of the IO address space that
is used by these cards.
MFC after: 1 day
implementation of heartbeat interval was 2 but there was typo which
caused the heartbeat is sent approximately every 5 seconds. This
caused unintended controller reset by firmware because firmware
thought OS was crashed.
Submitted by: Floris Bos < info <> je-eigen-domein dot nl >
Tested by: Andrzej Tobola < ato <> iem dot pw dot edu dot pl >
loopback.
- Change the meaning of "mix" OSS control. Now it controls loopback level,
according to comments in soundcard.h.
- Allow AD1981HD codecs to use playback mixer. Now driver should be able to
really use it.
- Fix bug in shared muters operation.
frames to be accepted while the driver is resetting the hardware.
This failure is generally observed when broadcast frames are received
during driver load and will generate "Unable to write CTX memory"
errors.
- Small changes to driver flags display.
This is not only a prudent thing to do, but also makes sure that probe
method is not confused by non-NULL 'private', if the previous attach
attempt fails for any reason.
PR: kern/142561
Tested by: Alex Goncharov <alex-goncharov@comcast.net>
MFC after: 4 days
chains. This part of code is to enhance performance so failing the
collapsing should not free TX frames. Otherwise bge(4) will
unnecessarily drop frames which in turn can freeze the network
connection.
Reported by: Igor Sysoev (is <> rambler-co dot ru)
Tested by: Igor Sysoev (is <> rambler-co dot ru)
copper and fiber interfaces over GMII so an explicit check is
necessary to know whether it was configured for fiber interface.
This change make BCM5715S work.
Tested by: olli
MFC after: 1 week
over GMII, make sure to enable GMII. With this change brgphy(4) is
used to handle the dual mode PHY. Since we still don't have a sane
way to pass PHY specific information to mii(4) layer special
handling is needed in brgphy(4) to determine which mode of PHY was
configured in parent interface.
This change make BCM5715S work.
Tested by: olli
Obtained from: OpenBSD
MFC after: 1 week
o Don't enable BGE_FLAG_BER_BUG on both 5722 and 5756, and based
on their PCI IDs rather than their chip IDs.
Reported by: several PC-BSD users via kmoore
Reviewed by: yongari, imp, jhb, davidch
Sponsored by: iXsystems, Inc.
MFC after: 2 weeks
from standard 3G wireless units by supplying a raw IP/IPv6 endpoint rather than
using PPP over serial. uhsoctl(1) is used to initiate and close the WAN
connection.
Obtained from: Fredrik Lindberg <fli@shapeshifter.se>
as different nearby ones, and was grabbed by MIXER_xxx() handler.
While there, replace '(cmd & MIXER_xxx(0)) == MIXER_xxx(0)' expressions
with more correct '(cmd & ~0xff) == MIXER_READ(0)'. Use of bit operations
to compare numeric fields doesn't looks sane.
MFC after: 1 month
now due to unidentified synchonization problem. For 7.1 soundcards 5.1
support handled correctly via software upmix done by sound(4).
Stereo stream is no more duplicated to all ports. If you loose sound, check
you are using right connectors. Front speakers connector is usually green,
center/LFE - orange, rear - black, side - gray.
Pertinant highlights from Myricom CHANGES file include:
- Make sure invalid external smbus activity cannot affect performance
- Fix to avoid a bug where the link could sometimes stay reported as
up on after unplugging the cable.
- For 8B NIC, make smbus connection passive at init to avoid
possible address conflicts
- Increase number of slices to 17 for multi-slice fw
- Fix a bug where packets dropped because of link_overflow could
be occasionally reported as bad_crc32
- Add selectable failover strategy for dual-port chip: symmetric or primary/backup
- On failover, send RARP broadcast to make the change immediately
known to the network
- Change endianess for PCI Device Serial Number
- For dual-port NICs, time to failover is now a few microsecs
instead of a few millisecs.
MFC after: 3 days
I/O port access is implemented on Itanium by reading and writing to a
special region in memory. To hide details and avoid misaligned memory
accesses, a process did I/O port reads and writes by making a MD system
call. There's one fatal problem with this approach: unprivileged access
was not being prevented. /dev/io serves that purpose on amd64/i386, so
employ it on ia64 as well. Use an ioctl for doing the actual I/O and
remove the sysarch(2) interface.
Backward compatibility is not being considered. The sysarch(2) approach
was added to support X11, but support for FreeBSD/ia64 was never fully
implemented in X11. Thus, nothing gets broken that didn't need more work
to begin with.
MFC after: 1 week
register, nVidia chipsets have different oppinion, requiring every interrupt
to be acknowledged there.
While there, add interrupt descriptions in multi-vector MSI mode.
Pass the channel argument as a real argument and not through
RXON. The RXON version seems to have problem with both the older
228.57.2.23 firmware and the latest 228.61.2.24 version resulting
in device initialization errors like:
wpa_supplicant[2928]: Failed to initiate AP scan.
kernel: firmware error log:
kernel: error type = "SYSASSERT" (0x00000005)
kernel: program counter = 0x0000147C
kernel: source line = 0x0000058B
kernel: error data = 0x0000058B00000000
kernel: branch link = 0x0000145A00001492
kernel: interrupt link = 0x000006DE00000000
kernel: time = 7310
...
kernel: iwn0: iwn_config: could not set TX power
kernel: iwn0: iwn_init_locked: could not configure device, error 35
By passing the current channel to hal->set_txpower() the firmware
error is fixed, at least for the 4965 chipset of my Thinkpad and
the ones tested by Bernhard.
Submitted by: Bernhard Schmidt <bschmidt@techwires.net>
Approved by: rpaulo
warning message and attach without setting the Ethernet address to a
random address. It is not believed that this code can actually be
executed, and if it does, we're better off printing an error message than
faking up an Ethernet address.
PR: kern/133239
Reviewed by: yongari (earlier version of patch)
Approved by: ed (mentor)
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.
command in the usb_msctest routines, as well as a general tidyup.
This now properly ejects the ZTE MF636, Option Gi0322 and Novatel MC950D
devices I have on my desk.
pci_delete_child() function called by the cardbus driver. The new function
uses resource_list_unreserve() to release the BARs decoded by the device
being removed.
Reviewed by: imp
Tested by: brooks
This should fix some Thinkpad specific problems such as
connecting to a headphone jack is not functional on X41.
Reviewed by: takawata
MFC after: 1 week
same ASIC ID of BCM5758 such that r198318 incorecctly enabled TSO
on BCM5754.BCM5754M controllers. BCM5754/BCM5754M needs a special
firmware to enable TSO and bge(4) does not support firmware based
TSO.
Reported by: ed
Tested by: ed
If the NAA is type 2, the Node WWN is the Port WWN with the 12 bits
of port (48..60) cleared. This iff a wwn fetched from NVRAM is zero.
MFC after: 1 week
Unfortunately there are two slight problems with that:
- Yacc and lex might generate code that generates warnings because of
this. Require yacc and lex to be rebuilt during bootstrap. I'm not
incrementing __FreeBSD_version here, because I assume someone else
will do this eventually.
- When running `make buildkernel', it uses share/mk from the source
treeo to build aicasm. Because aicasm also depends on lex, this would
break. Lower WARNS to 5 for now. We should just increment it to 6
again somewhere in the very far future.
stored in a BAR since the CIS BAR is mapped before the PCI bus driver
enumerates all the BARs. Without this change, the PCI bus driver would
attempt to initialize a BAR that was already allocated resulting in a panic.
handling for the PCIR_BIOS decoding enable bit from the cardbus driver.
The PCIR_BIOS BAR does include type bits like other BARs. Instead, it is
always a 32-bit non-prefetchable memory BAR where the low bit is used as a
flag to enable decoding.
Reviewed by: imp
This replaces d_mmap() with the d_mmap2() implementation and also
changes the type of offset to vm_ooffset_t.
Purge d_mmap2().
All driver modules will need to be rebuilt since D_VERSION is also
bumped.
Reviewed by: jhb@
MFC after: Not in this lifetime...
get required command protocol. But they have no idea about new commands,
such as DATA SET MANAGEMENT (TRIM). As soon as this info any way provided
by CAM, give controller specific instructions.
* new firmware
* untested support for 1000 and 6000 series
* bgscan support
* remove unnecessary RXON changes
* allow setting of country/regdomain by enforcing channel flags read
from the EEPROM
* suspend/resume fixes
* RF kill switch fixes
* LED adjustments
* several bus_dma*() related fixes
* addressed some LORs
* many other bug fixes
Submitted by: Bernhard Schmidt <bschmidt at techwires.net>
Obtained from: Brandon Gooch <jamesbrandongooch at gmail dot com> (LED
related changes), Benjamin Kaduk <kaduk at mit dot edu>
(LOR fixes), OpenBSD
Fix some wrong usages.
Note: this does not affect generated binaries as this argument is not used.
PR: 137213
Submitted by: Eygene Ryabinkin (initial version)
MFC after: 1 month
blkif interface in Xen requires all I/O to be 512 byte aligned with each
segment bounded by a 4k page.
Note: This submission only documents the proper contraints for blkif I/O.
The alignment code in busdma does not yet handle alignment constraints
correctly in all cases.
* Correct a group of typos: for Core2 programmable events, check
user supplied umask values against the correct event descriptor
field.
Submitted by: Ryan Stone <rysto32 at gmail dot com>
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.
This brings hwpmc(4) support for 2nd and 3rd generation XScale cores.
Right now it's enabled by default to make sure we test this a bit.
When the time comes it can be disabled by default.
Tested on Gateworks boards.
A man page is coming.
Obtained from: //depot/user/rpaulo/xscalepmc/...
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().
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.
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.
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.
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.
is that the JBus to EBus bridges share the interrupt controller of a
sibling JBus to PCIe bridge (at least as far as the OFW device tree
is concerned, in reality they are part of the same chip) so we have to
probe and attach the latter first. That happens to be also the case
due to the fact that the JBus to PCIe bridges appear first in the OFW
device tree but it doesn't hurt to ensure the right order.
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().
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().
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().
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.
the leading underscores since they are now implemented.
- Implement the tcpi_rto and tcpi_last_data_recv fields in the tcp_info
structure.
Reviewed by: rwatson
MFC after: 2 weeks
This device only appears on the ACPI bus, so isn't caught by the current
entry for it in the uart(4) ISA attachment.
PR: kern/140172
Reviewed by: jhb, marcel
Approved by: ed (mentor)
MFC after: 2 weeks
causes additional MSIs messages sent if several ports asked for attention
same time. Time window before clearing is not important, as these interrupts
are level triggered by interrupt source.