Linux ath9k doesn't have this issue as it doesn't try queuing multi-
descriptor frames to the hardware.
Before, I was only setting the first and last descriptor in the final
frame correctly - and that was done by accident. The first descriptor in
the last sub-frame was being correctly updated by ath_tx_setds_11n();
the last descriptor in the last sub-frame was being correctly updated
by ath_buf_set_rate(). But both of those are "incorrect".
The correct behaviour is:
* AR_IsAggr is set for all descriptors for all subframes in an aggregate.
* AR_MoreAggr is set for all descriptors for all non-final sub-frames
in an aggregate.
Ie, all descriptors in the last sub-frame of an aggregate must have this
field set to 0.
I still need to do a couple of extra passes to ensure the pad delimiter
field is being correctly handled in all descriptors in the last sub-frame.
Right now ath_txq_sched() is mainly called from the TX ath_tx_processq()
routine, which is (mostly) done as part of the taskqueue. It shouldn't
be called outside the taskqueue.
But now that I'm about to flip back on BAR TX, I'm going to start
stressing the ath_tx_tid_pause() and ath_tx_tid_resume() paths.
What I don't want to have happen is a reschedule of the TID traffic
_during_ the completion of TX frames.
Ideally I'd like to have a way to flag back up to the processing code
that the current hardware queue should be rechecked for software TID
queue frames. But for now, this should suffice for the BAR TX case.
I may eventually delete this code once I've brought some further
sanity to the general TX queue/completion path.
within the BAW.
This regression was introduced in ane earlier commit by me to fix the
BAW seqno allocation-but-not-insertion-into-BAW race. Since it was only
ever using the to-be allocated sequence number, any frame retries
with the first frame in the BAW still in the software queue would
have constantly failed, as ni_txseqs[tid] would always be outside
the BAW.
TODO:
* Extract out the mostly common code here in the agg and non-agg ADDBA
case and stuff it into a single function.
PR: kern/166357
I see traffic stalls.
It turns out that the bug isn't because the first and last frame in the
BAW is in the software queue. It is more likely that it's because
the first frame in the BAW is still in the software queue and thus there's
no more room to allocate and do subsequent TX.
PR: kern/166357
This is not entirely correct as it simply resets the channel, flushing
whatever is in the TX/RX queue. This can and will break aggregation
BAW tracking. But the alternative (HT40 frames being sent with the hardware
in HT20 mode) is even worse.
There's still a small window between the htinfo being received (and the ni_chw
field being updated) which could cause problems. I'll look at fleshing this
out in follow-up commits.
PR: kern/166286
is queued to the hardware.
Because multiple concurrent paths can execute ath_start(), multiple
concurrent paths can push frames into the software/hardware TX queue
and since preemption/interrupting can occur, there's the possibility
that a gap in time will occur between allocating the sequence number
and queuing it to the hardware.
Because of this, it's possible that a thread will have allocated a
sequence number and then be preempted by another thread doing the same.
If the second thread sneaks the frame into the BAW, the (earlier) sequence
number of the first frame will be now outside the BAW and will result
in the frame being constantly re-added to the tail of the queue.
There it will live until the sequence numbers cycle around again.
This also creates a hole in the RX BAW tracking which can also cause
issues.
This patch delays the sequence number allocation to occur only just before
the frame is going to be added to the BAW. I've been wanting to do this
anyway as part of a general code tidyup but I've not gotten around to it.
This fixes the PR.
However, it still makes it quite difficult to try and ensure in-order
queuing and dequeuing of frames. Since multiple copies of ath_start()
can be run at the same time (eg one TXing process thread, one TX completion
task/one RX task) the driver may end up having frames dequeued and pushed
into the hardware slightly/occasionally out of order.
And, to make matters more annoying, net80211 may have the same behaviour -
in the non-aggregation case, the TX code allocates sequence numbers
before it's thrown to the driver. I'll open another PR to investigate
this and potentially introduce some kind of final-pass TX serialisation
before frames are thrown to the hardware. It's also very likely worthwhile
adding some debugging code into ath(4) and net80211 to catch when/if this
does occur.
PR: kern/166190
* printf -> device_printf
* print the buffer pointer and sequence number for any buffer that wasn't
correctly tidied up before it was freed. This is to aid in some
current SMP TX debugging stalls.
PR: kern/166190
Although access to the flags to check/set OACTIVE is racy due to how
the default if_start() function works, this should remove any races
with read/modify/write between threads.
don't setup the avp mcast queue.
This is a bit annoying though - it turns out the mcast queue isn't
initialised for STA mode but it's then touched to see whether anything
is in it. That should be fixed in a subsequent commit.
Noticed by: gperez@entel.upc.edu
PR: kern/165895
In a very noisy 2.4GHz environment (with HT/40 enabled, making it worse)
I saw the following occur:
* the air was considered "busy" a lot of the time;
* the cabq time is quite short due to staggered beacons being enabled;
* it just wasn't able to keep up TX'ing CABQ frames;
* .. and the cabq would swallow up all the TX ath_buf's.
This patch introduces a twiddle which allows the maximum cabq depth to be
set, forcing further frames to be dropped.
It defaults to the TX buffer count at the moment, so the default behaviour
isn't changed.
I've also started fleshing out a similar setup for the data path, so
it doesn't swallow up all the available TX buffers and preventing management
frames (such as ADDBA) out.
PR: kern/165895
frames with stations in power saving mode.
I'm not (yet) sure how to handle TX'ing aggregates frames to stations
that are in power saving mode, or whether that's even a feasible thing
to do. So in order to (mostly) not forget, leave a couple of comments
in the code.
The code presently assumes that the aggregation TID state for an ath_node
is locked not by the ath_node lock or a node+TID lock, but behind the
hardware queue said TID maps to. This assumption is going to be
incorrect for stations in power saving mode as we'll be TX'ing frames
on the multicast queue.
In any case, I'm afraid its a "later problem". :/
This function must be called with both the source and destination TXQs
locked or things will get hairy.
I added this as part of some debugging in a PR but it turned out to not
be the cause. I still think it's -correct- so, here it is.
the last buffer in the list.
The current behaviour (due to me, so pointy hat is firmly on my head here)
was incorrect - it was setting the link pointer to the last descriptor
of the _first_ buffer in the TXQ. Instead, it should have set it to the
last descriptor in the _last_ buffer in the TXQ.
This showed up as occasional TX stalls with frames in the TXQ but no
TX progress being made. Further inspection showed the TXQ looked like
it contained multiple "lists" of frames - there'd be a list of correct
frames, then a NULL link pointer, but there'd be a next buffer in the
list.
Since this code is only called upon an interface reset, it's likely
this only began showing up when I started doing stress testing
in environments which annoy the radios enough to cause lockups.
I've not yet any TX stalls with this patch applied.
PR: kern/165866
been bait-and-switched from the rate control code.
This will avoid the panic that I saw and will avoid sending invalid rates
(eg 11a/11g OFDM rates when in 11b, on 11b-only NICs (AR5211)) where the
rate table is not "big".
It also will point out situations where this occurs for the 11n NICs
which will have sufficiently large rate tables that "invalid rix" doesn't
occur.
I'll try to follow this up with a commit that adds a current operating mode
check. The "rix" is only relevant to the current operating mode and rate
table.
PR: kern/165475
* ath_reset() is being called in softclock context, which may have the
thing sleep on a lock. To avoid this, since we really _shouldn't_
be sleeping on any locks, break out the no-loss reset path into a tasklet
and call that from:
+ ath_calibrate()
+ ath_watchdog()
This has the added advantage that it'll end up also doing the frame
RX cleanup from within the taskqueue context, rather than the softclock
context.
* Shuffle around the taskqueue_block() call to be before we grab the lock
and disable interrupts.
The trouble here is that taskqueue_block() doesn't block currently
queued (but not yet running) tasks so calling it doesn't guarantee
no further tasks (that weren't running on _A_ CPU at the time of this
call) will complete. Calling taskqueue_drain() on these tasks won't
work because if any _other_ thread calls taskqueue_enqueue() for whatever
reason, everything gets very angry and stops working.
This slightly changes the race condition enough to let ath_rx_tasklet()
run before we try disabling it, and thus quietens the warnings a bit.
The (more) true solution will be doing something like the following:
* having a taskqueue_blocked mask in ath_softc;
* having an interrupt_blocked mask in ath_softc;
* only calling taskqueue_drain() on each individual task _after_ the
lock has been acquired - that way no further tasklet scheduling
is going to occur.
* Then once the tasks have been blocked _and_ the interrupt has been
disabled, call taskqueue_drain() on each, ensuring that anything
that _was_ scheduled or running is removed.
The trouble is if something calls taskqueue_enqueue() on a task
after taskqueue_blocked() has been called but BEFORE taskqueue_drain()
has been called, ta_pending will be set to 1 and taskqueue_drain()
will sit there stuck in msleep() until you hard-kill the machine.
PR: kern/165382
PR: kern/165220
I'm not sure _why_ the ic is NULL here, but I've seen it occasionally do
this after I've been tinkering with things for a while. It ends up
crashing in a call to ath_chan_set() via the net80211 scan code and scan
task.
hold the lock.
This is part of my series of work to try and capture when net80211
locking isn't.
ObNote: it'd be nice to be able to mark a lock as "assert if the lock
is dropped", so I could capture functions which decide that dropping
and reacquiring the lock is a good idea (without re-checking the
sanity of the state protected by the lock.)
with RX/TX halting.
* Always disable/enable interrupts during a channel change, just to simply
things.
* Ensure that the ath taskqueue has completed and is paused before
continuing.
This dramatically reduces the instances of overlapping RX and reset
conditions.
PR: kern/165220
There are unfortunately a number of situations where vap->iv_bss is changed
or freed by some code in net80211. Because multiple threads can concurrently
be doing work (and the vap->iv_bss access isn't at all done behind any kind
of lock), it's quite possible that:
* a change will occur in one thread - eg, by a call through
ieee80211_sta_join1();
* a state change occurs in another thread - eg an RX is scheduled
in the ath tasklet and it calls ieee80211_input_mimo_all(), which
does dereference vap->iv_bss;
* these two executing concurrently, causing things to explode.
Another instance is ath_beacon_alloc() which takes an ieee80211_node *.
It's called with the vap->iv_bss node from ath_newstate(). If the node has
changed in the meantime (say it's been freed elsewhere) the reference
that it grabbed _before_ refcounting it may be stale.
I would _prefer_ that these sorts of things were serialised somewhere but
that may be a bit much to ask. Instead, the best we can (currently) hope
is that the underlying bss node is still (somewhat) valid.
There is a related PR (kern/164382) described by the first case above.
That should be fixed by properly serialising the RX path and reset path
so an RX can't occur at the same time as the vap free/shutdown path.
This is inspired by some related fixes in r212127.
PR: kern/165060
overridden at attach time.
Some 802.11n NICs may only have one physical antenna connected.
The radios will be very upset if you try enabling radios which aren't
connected to antennas.
This allows hints to override the TX and RX chainmask.
These hints are:
hint.ath.X.rx_chainmask
hint.ath.X.tx_chainmask
They can be set at either boot time or in kenv before the module is loaded.
This and the previous HAL commit were sponsored in late 2011 by Hobnob, Inc.
Sponsored by: Hobnob, Inc.
by capabilities.
Add an ar5416SetCapability() function, which contains logic to override
the chainmask and update the relevant stream.
This is designed to be called after the attach function, which presets
the TX/RX chainmask and stream.
TODO: check the chainmask against the hardware chainmask so non-existing
chains aren't enabled.
radar parameters for the AR5416 and later NICs.
These parameters have been tested on the following NICs:
* AR5416
* AR9160
* AR9220
* AR9280
And yes, these will return radar pulse parameters and (for AR9160 and later)
radar FFT information as PHY errors.
This is again not enough to do radar detection, it's just here to faciliate
development and validation of radar detection algorithms.
The (pulse, not FFT) decoding code for AR5212, AR5416 and later NICs exist
in the HAL.
This code is disabled for now as generating radar PHY errors can quickly
cause issues in busy environment.s Some further debugging of the RX path
is needed.
Finally, these parameters are likely not useful for the AR5212 era NICs.
The madwifi-dfs branch should have suitable example parameters for the
11a era NICs.
* Override the TX/RX stream count if the EEPROM reports a single RX or
TX stream, rather than assuming the device will always be a 2x2 strea
device.
* For AR9280 devices, don't hard-code 2x2 stream. Instead, allow the
ar5416FillCapabilityInfo() routine to correctly determine things.
The latter should be done for all 11n chips now that
ar5416FillCapabilityInfo() will set the TX/RX stream count based on the
active TX/RX chainmask in the EEPROM.
Thanks to Maciej Milewski for donating some AR9281 NICs to me for
testing.
* For legacy NICs, the combined RSSI should be used.
For earlier AR5416 NICs, use control chain 0 RSSI rather than combined
RSSI.
For AR5416 > version 2.1, use the combined RSSI again.
* Add in a missing AR5212 HAL method (get11nextbusy) which may be called
by radar code.
This serves no functional change for what's currently in FreeBSD.
* Grab the net80211com lock when calling ieee80211_dfs_notify_radar().
* Use the tsf extend function to turn the 64 bit base TSF into a per-
frame 64 bit TSF. This will improve radiotap logging (which will
now have a (more) correct per-frame TSF, rather then the single TSF64
value read at the beginning of ath_rx_proc().
to being more generic.
Other embedded SoCs also throw the configuration/PCI register
info into flash.
For now I'm just hard-coding the AR9280 option (for on-board AR9220's on
AP94 and commercial designs (eg D-Link DIR-825.))
TODO:
* Figure out how to support it for all 11n SoC NICs by doing it in
ar5416InitState();
* Don't hard-code the EEPROM size - add another field which is set
by the relevant chip initialisation code.
* 'owl_eep_start_loc' may need to be overridden in some cases to 0x0.
I need to do some further digging.
where they've disabled all the wireless devices/framework.
This is just a build workaround. If you're actively using wireless,
you must still define AH_SUPPORT_AR5416 as I'm not sure what else
will break!
The real solution is to make the module build depend if AH_SUPPORT_AR5416
is defined, as well as make the 11n code in if_ath_tx.c and if_ath_tx_ht.c
completely optional (maybe depend upon ATH_SUPPORT_11N.)
This shows that the majority of the weird traffic I see here are probe
frames that haven't been sent out, but I can also trigger this condition
by doing ICMP w/ -i 0.3 - enough to trigger the TX during actual scanning,
but not fast enough to stop scanning from occuring.
PR: kern/163689
doing split software/hardware LED configuration, we can now simply
treat "softled" as an "output" mux type.
This works fine on this DWA-552. Previous generation (pre-11n NICs) don't
have a GPIO mux - only input/output configuration - so they ignore this
field.
The hardware (MAC) LED blinking involves a few things:
* Selecting which GPIO pins map to the MAC "power" and "network" lines;
* Configuring the MAC LED state (associated, scanning, idle);
* Configuring the MAC LED blinking type and speed.
The AR5416 HAL configures the normal blinking setup - ie, blink rate based
on TX/RX throughput. The default AR5212 HAL doesn't program in any
specific blinking type, but the default of 0 is the same.
This code introduces a few things:
* The hardware led override is configured via sysctl 'hardled';
* The MAC network and power LED GPIO lines can be set, or left at -1
if needed. This is intended to allow only one of the hardware MUX
entries to be configured (eg for PCIe cards which only have one LED
exposed.)
TODO:
* For AR2417, the software LED blinking involves software blinking the
Network LED. For the AR5416 and later, this can just be configured
as a GPIO output line. I'll chase that up with a subsequent commit.
* Add another software LED blink for "Link", separate from "activity",
which blinks based on the association state. This would make my
D-Link DWA-552 have consistent and useful LED behaviour (as they're
marked "Link" and "Activity."
* Don't expose the hardware LED override unless it's an AR5416 or later,
as the previous generation hardware doesn't have this multiplexing
setup.
Some of the NICs I have here power up with the LEDs blinking, which is
incorrect. The blinking should only occur when the NIC is attempting
to associate.
* On powerup, set the state to HAL_LED_INIT, which turns on the "Power" MAC
LED but leaves the "Network" MAC LED the way it is.
* On resume, also init it to HAL_LED_INIT unless in station mode, where
it's forced to HAL_LED_RUN. Hopefully the net80211 state machine will
call newstate() at some point, which will refiddle the LEDs.
I've tested this on a handful of 11n and pre-11n NICs. The blinking
behaviour is slightly more sensible now.
relying on what the register defaults are.
This forces the blink mode to be proportional to the TX and RX frames
which match the RX filter.
This (along with a few tweaks to if_ath_led.c to configure the correct
GPIO pins) allows my DWA-552 AR5416 NIC to blink the LEDs in a useful
fashion, however those LEDs are marked "Link" and "Act(ivity)", which
don't really map well to the "power" / "network" LED interface which
the MAC provides. Some further tinkering is needed to see what other
useful operating modes are possible.
state from correctly updating things.
The reference driver directly enables/disables the LED state as required,
rather than nailing it up like it currently is. That'll have to come
later by adding some further HAL methods.
Obtained from: Atheros
* Bring the AR5416 GPIO mux mask code in line with the code from the
HAL.
* Add HAL_DEBUG_GPIO debugging statements, to track what's going on.
* Add Kiwi GPIO specific changes for reading values back.
Obtained from: Atheros
* As a preparation for AR9287 GPIO support, add in the AR9287 GPIO mask.
* Fix the association mask values; these are post-shift values but were
being shifted in twice. This resulted in some garbage being written
in the wrong place and the link LED (at least on my d-link AR5416
NIC) giving totally incorrect blink patterns.
Some users were reporting concurrent resets _were_ occuring - ie,
either two ath_reset()s ran at the same time (likely one on each CPU)
or ath_reset() versus ath_chan_change().
Instead, this now tries to grab the serialisation semaphore and will
pause() for a while if it fails. It will always eventually succeed though
and will log an error if it hits the recursion situation.
All of this stuff needs to die a horrible death at some point and be
replaced with a properly serialising method of programming this stuff
(eg using the net80211 taskqueue for all of this stuff.) The trouble
is figuring out how to handle the concurrent ioctl() based things without
introducing more LORs (which is another reason why I haven't just wrapped
all of this stuff in large, long-lived locks, a-la what Linux can get
away with.)
MFC after: Absolutely, positively never.
This doesn't fix compilation w/out AH_SUPPORT_AR5416 as all of the software
aggregation support in if_ath_tx.c and 11n code in if_ath_tx_ht.c touches
the 11n specific fields. I'll work on that later.
going on with the occasional garbage rs_antenna field reported by AR9285
users.
I've discovered that the 11n NICs only fill out the entire RX status
descriptor on the final descriptor in an aggregate. Some of the fields
(notably RSSI) are complete nonsense for A-MPDU subframes. This may
be another example of this.
The driver doesn't currently toss out statistics for non-final aggregate
frames. It's likely that this should be done.
If any users hit this particular debugging message they should report it
immediately to freebsd-wireless@freebsd.org - please ensure you have
ATH_DEBUG enabled so it prints out the full receive descriptor.
PR: kern/163312
There's currently no public code which uses this feature and the
current reference driver doesn't enable this feature at all.
It's possible it was used by a previous version of the driver and
that indeed it should return HAL_STATUS; but at this point I'm
happy to require that they complain and submit a patch.
This was found by LLVM compile-time type checking.
Submitted by: dim
and sys/dev/ath/ath_hal/ar5416/ar5416_misc.c:
sys/dev/ath/ath_hal/ar5212/ar5212_misc.c:577:24: warning: implicit conversion from enumeration type 'HAL_STATUS' to different enumeration type 'HAL_BOOL' [-Wconversion]
return HAL_EINVAL;
~~~~~~ ^~~~~~~~~~
and:
sys/dev/ath/ath_hal/ar5416/ar5416_misc.c:164:9: warning: implicit conversion from enumeration type 'HAL_STATUS' to different enumeration type 'HAL_BOOL' [-Wconversion]
return HAL_OK;
~~~~~~ ^~~~~~
In both cases, enums HAL_BOOL and HAL_STATUS are mixed up.
MFC after: 1 week
and sys/dev/ath/ath_hal/ar5211/ar5211_power.c:
sys/dev/ath/ath_hal/ar5210/ar5210_power.c:36:3: warning: signed shift result (0x200000000) requires 35 bits to represent, but 'int' only has 32 bits [-Wshift-overflow]
OS_REG_RMW_FIELD(ah, AR_SCR, AR_SCR_SLE, AR_SCR_SLE_ALLOW);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sys/dev/ath/ath_hal/ah_internal.h:472:42: note: expanded from:
(OS_REG_READ(_a, _r) &~ (_f)) | (((_v) << _f##_S) & (_f)))
^
sys/dev/ath/ah_osdep.h:127:49: note: expanded from:
(bus_space_handle_t)(_ah)->ah_sh, (_reg), (_val))
^~~~
The AR_SCR_SLE_{WAKE,SLP,NORM} values are pre-shifted in ar5210reg.h and
ar5211reg.h, while they should be unshifted, like in ar5212reg.h. Then,
when the OS_REG_RMW_FIELD() macro shifts them again, the values will
overflow, becoming effectively zero.
MFC after: 1 week
attached this way.
The AR5212 based NICs have a variety of RF frontends, so there's a linker set
which the AR5212 attach routine calls. The same framework is used for the
AR5416 and later but as there's a fixed RF frontend for each 11n NIC, it
is just directly attached.
However in the case of compiling a cut down HAL (eg _just_ AR9130 WMAC support),
the linker set ends up being empty and this causes the compile to fail.
So this is just a workaround for that - it means those users who wish an 11n
only HAL can compile the 11n chipsets and RF frontend they need, and just
"ath_ar5212" for the AR5212/AR5416 common code, and it'll just work.
Sponsored by: Hobnob, Inc.
The calibrate callout is done with the sc lock held.
This only showed up when using an older NIC (AR5212) whose
radio/phy requires the rfgain adjustment.
Pointy-hat-to: adrian
Sponsored by: Hobnob, Inc.
* Failall is now named just that.
* Add TX ok and TX fail, for aggregate frame sub-frames.
This will break athstats; a followup commit wil resolve this.
Sponsored by: Hobnob, Inc.
This fixes panics that users have been seeing when operating in station mode,
where the interface undergoes a lot more resets then in hostap mode (ie whilst
doing channel scanning.)
Reported by: arundel, wblock@wonkity.com
Sponsored by: Hobnob, Inc.
mode configuration registers. This is apparently required for correct
behaviour, but also requires the chip to actually officially support it.
Sponsored by: Hobnob, Inc.
"correct" handling of frames in the RX pending queue during interface
transitions.
* ath_stoprecv() doesn't blank out the descriptor list - that's what
ath_startrecv() does. So, change a comment to reflect that.
* ath_stoprecv() does include a large (3ms) delay to let pending DMA
complete. However, I'm under the impression that the stopdma hal
method does check for a bit in the PCU to indicate DMA has stopped.
So, to help with fast abort and restart, modify ath_stoprecv() to take
a flag which indicates whether this is needed.
* Modify the uses of ath_stoprecv() to pass in a flag to support the
existing behaviour (ie, do the delay.)
* Remove some duplicate PCU teardown code (which wasn't shutting down DMA,
so it wasn't entirely correct..) and replace it with a call to
ath_stoprecv(sc, 0) - which disables the DELAY call.
The upshoot of this is now channel change doesn't simply drop completed
frames on the floor, but instead it cleanly handles those frames.
It still discards pending TX frames in the software and hardware queues
as there's no (current) logic which forcibly recalculates the rate control
information (or whether they're appropriate to be on the TX queue after
a channel change), that'll come later.
This still doesn't stop all the sources of queue stalls but it does
tidy up some of the code duplication.
To be complete, queue stalls now occur during normal behaviour -
they only occur after some kind of broken behaviour causes an interface
or node flush, upsetting the TX/RX BAW. Subsequent commits will
incrementally fix these and other related issues.
Sponsored by: Hobnob, Inc.
for the ath(4) driver.
Currently, there's nothing stopping reset, channel change and general
TX/RX from overlapping with each other. This wasn't a big deal with
pre-11n traffic as it just results in some dropped frames.
It's possible this may have also caused some inconsistencies and
badly-setup hardware.
Since locks can't be held across all of this (the Linux solution)
due to LORs with the network stack locks, some state counter
variables are used to track what parts of the code the driver is
currently in.
When the hardware is being reset, it disables the taskqueue and
waits for pending interrupts, tx, rx and tx completion before
it begins the reset or channel change.
TX and RX both abort if called during an active reset or channel
change.
Finally, the reset path now doesn't flush frames if ATH_RESET_NOLOSS
is set. Instead, completed TX and RX frames are passed back up to
net80211 before the reset occurs.
This is not without problems:
* Raw frame xmit are just dropped, rather than placed on a queue.
The net80211 stack should be the one which queues these frames
rather than the driver.
* It's all very messy. It'd be better if these hardware operations
were serialised on some kind of work queue, rather than hoping
they can be run in parallel.
* The taskqueue block/unblock may occur in parallel with the
newstate() function - which shuts down the taskqueue and restarts
it once the new state is known. It's likely these operations should
be refcounted so the taskqueue is restored once no other areas
in the code wish to suspend operations.
* .. interrupt disable/enable should likely be refcounted as well.
With this work, the driver does not drop frames during stuck beacon
or fatal errors and thus 11n traffic continues to run correctly.
Default and full resets however do still drop frames and it's possible
this may occur, causing traffic loss and session stalls.
Sponsored by: Hobnob, Inc.
I need to investigate this a little closer, but it seems that in noisy
environments the NF load takes longer than 5 * DELAY(10) and this is
messing up future NF calibrations. (The background: NF calibrations
begin at the value programmed in after the load has completed, so
if this is never loaded in, the NF calibrations only ever start at
the currently calibrated NF value, rather than starting at something
high (say -50.)
More investigation about the effect on 11n RX and calibration results
are needed.
Sponsored by: Hobnob, Inc.
The AR5416 MAC (which shows up in the AR5008, AR9001, AR9002 devices) has
issues with PCI transactions on SMP machines. This work-around enforces
that register access is serialised through a (global for now) spinlock.
This should stop the hangs people have seen with the AR5416 PCI devices
on SMP hosts.
Obtained by: Linux, Atheros
it's cloned and that clone is retransmitted. This means that the
ath_buf pointer squirreled away on the baw window array is suddenly
wrong and was causing all kinds of console output.
This updates the pointer in that particular BAW slot to the new
ath_buf after ensuring that:
* the new and old buffers have the same seqno;
* the current slot pointer matches the old buffer pointer.
This quietens the debugging output (again), restoring said debugging
to only signify when a broken condition has occured.
Sponsored by: Hobnob, Inc.
to fetch the current channel busy statistics, rather than duplicating
it here.
This forms the (very crude) basis for doing basic channel surveying.
Sponsored by: Hobnob, Inc.
enabled if required by STA operation.
This quietens a lot of OFDM errors seen in hostap mode, where
there are no beacon RSSI levels to tune the dynamic range of the
baseband.
This may reduce reception range at the fringes, but does increase
stability.
Sponsored by: Hobnob, Inc.
The 5ghz hostap mode (where DFS is being done) requires ANI to be disabled
or the radar detection parameters don't work as advertised (as they're based
on signal strength level, and tweaking ANI affects the signal strangth,
dynamic range and power increase the baseband is looking for in order to
detect it as a "signal".)
Obtained from: Linux, Atheros
Sponsored by: Hobnob, Inc.
