Commit Graph

57 Commits

Author SHA1 Message Date
Adrian Chadd
1ca3996828 [ath] Add ast_tsfoor to the sysctl statistics array. 2021-05-22 15:54:16 -07:00
Mateusz Guzik
9966c0f962 ath: clean up empty lines in .c and .h files 2020-09-01 21:41:07 +00:00
Adrian Chadd
8c01c3dc46 [ath] [ath_hal] Propagate the HAL_RESET_TYPE through to the chip reset; set it during ath_reset()
Although I added the reset type field to ath_hal_reset() years ago,
I never finished adding it both throughout the HALs and in if_ath.c.

This will eventually deprecate the ath_hal force_full_reset option
because it can be requested at the driver layer.

So:

* Teach ar5416ChipReset() and ar9300_chip_reset() about the HAL type
* Use it in ar5416Reset() and ar9300_reset() when doing a full chip reset
* Extend ath_reset() to include the HAL_RESET_TYPE parameter added in the above functions
* Use HAL_RESET_NORMAL in most calls to ath_reset()
* .. but use HAL_RESET_BBPANIC for the BB panics, and HAL_RESET_FORCE_COLD during fatal, beacon miss and other hardware related hangs.

This should be a glorified no-op outside of actual hardware issues.
I've tested things with ath_hal force_full_reset set to 1 for years now,
so I know that feature and a full reset works (albeit much slower than
a warm reset!) and it does unwedge hardware.

The eventual aim is to use this for all the places where the driver
detects a potential hang as well as if long calibration - ie, noise floor
calibration - fails to complete. That's one of the big hardware related
things that causes station mode operation to hang without easy recovery.

Differential Revision:	https://reviews.freebsd.org/D24981
2020-05-25 22:31:45 +00:00
Pawel Biernacki
08f5e6bb81 Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (7 of many)
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all low hanging fruits as MPSAFE.

Reviewed by:	markj
Approved by:	kib (mentor, blanket)
Differential Revision:	https://reviews.freebsd.org/D23626
2020-02-21 16:32:17 +00:00
Pedro F. Giffuni
718cf2ccb9 sys/dev: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 14:52:40 +00:00
Adrian Chadd
729ecfbb8e [ath] report node queue overflows.
I need to also update athstats to report this too.
2016-06-09 21:59:36 +00:00
Adrian Chadd
3c6b488b01 [ath] Add counters for STBC TX and LDPC TX.
This is a big no-op until the TX path changes to enable LDPC TX are
added.
2016-04-29 01:51:27 +00:00
John Baldwin
cbc4d2db75 Remove taskqueue_enqueue_fast().
taskqueue_enqueue() was changed to support both fast and non-fast
taskqueues 10 years ago in r154167.  It has been a compat shim ever
since.  It's time for the compat shim to go.

Submitted by:	Howard Su <howard0su@gmail.com>
Reviewed by:	sephe
Differential Revision:	https://reviews.freebsd.org/D5131
2016-03-01 17:47:32 +00:00
Gleb Smirnoff
7a79cebfba Replay r286410. Change KPI of how device drivers that provide wireless
connectivity interact with the net80211 stack.

Historical background: originally wireless devices created an interface,
just like Ethernet devices do. Name of an interface matched the name of
the driver that created. Later, wlan(4) layer was introduced, and the
wlanX interfaces become the actual interface, leaving original ones as
"a parent interface" of wlanX. Kernelwise, the KPI between net80211 layer
and a driver became a mix of methods that pass a pointer to struct ifnet
as identifier and methods that pass pointer to struct ieee80211com. From
user point of view, the parent interface just hangs on in the ifconfig
list, and user can't do anything useful with it.

Now, the struct ifnet goes away. The struct ieee80211com is the only
KPI between a device driver and net80211. Details:

- The struct ieee80211com is embedded into drivers softc.
- Packets are sent via new ic_transmit method, which is very much like
  the previous if_transmit.
- Bringing parent up/down is done via new ic_parent method, which notifies
  driver about any changes: number of wlan(4) interfaces, number of them
  in promisc or allmulti state.
- Device specific ioctls (if any) are received on new ic_ioctl method.
- Packets/errors accounting are done by the stack. In certain cases, when
  driver experiences errors and can not attribute them to any specific
  interface, driver updates ic_oerrors or ic_ierrors counters.

Details on interface configuration with new world order:
- A sequence of commands needed to bring up wireless DOESN"T change.
- /etc/rc.conf parameters DON'T change.
- List of devices that can be used to create wlan(4) interfaces is
  now provided by net.wlan.devices sysctl.

Most drivers in this change were converted by me, except of wpi(4),
that was done by Andriy Voskoboinyk. Big thanks to Kevin Lo for testing
changes to at least 8 drivers. Thanks to pluknet@, Oliver Hartmann,
Olivier Cochard, gjb@, mmoll@, op@ and lev@, who also participated in
testing.

Reviewed by:	adrian
Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2015-08-27 08:56:39 +00:00
Adrian Chadd
ba2c1fbc03 Revert the wifi ifnet changes until things are more baked and tested.
* 286410
* 286413
* 286416

The initial commit broke a variety of debug and features that aren't
in the GENERIC kernels but are enabled in other platforms.
2015-08-08 01:10:17 +00:00
Gleb Smirnoff
79d2c5e857 Change KPI of how device drivers that provide wireless connectivity interact
with the net80211 stack.

Historical background: originally wireless devices created an interface,
just like Ethernet devices do. Name of an interface matched the name of
the driver that created. Later, wlan(4) layer was introduced, and the
wlanX interfaces become the actual interface, leaving original ones as
"a parent interface" of wlanX. Kernelwise, the KPI between net80211 layer
and a driver became a mix of methods that pass a pointer to struct ifnet
as identifier and methods that pass pointer to struct ieee80211com. From
user point of view, the parent interface just hangs on in the ifconfig
list, and user can't do anything useful with it.

Now, the struct ifnet goes away. The struct ieee80211com is the only
KPI between a device driver and net80211. Details:

- The struct ieee80211com is embedded into drivers softc.
- Packets are sent via new ic_transmit method, which is very much like
  the previous if_transmit.
- Bringing parent up/down is done via new ic_parent method, which notifies
  driver about any changes: number of wlan(4) interfaces, number of them
  in promisc or allmulti state.
- Device specific ioctls (if any) are received on new ic_ioctl method.
- Packets/errors accounting are done by the stack. In certain cases, when
  driver experiences errors and can not attribute them to any specific
  interface, driver updates ic_oerrors or ic_ierrors counters.

Details on interface configuration with new world order:
- A sequence of commands needed to bring up wireless DOESN"T change.
- /etc/rc.conf parameters DON'T change.
- List of devices that can be used to create wlan(4) interfaces is
  now provided by net.wlan.devices sysctl.

Most drivers in this change were converted by me, except of wpi(4),
that was done by Andriy Voskoboinyk. Big thanks to Kevin Lo for testing
changes to at least 8 drivers. Thanks to Olivier Cochard, gjb@, mmoll@,
op@ and lev@, who also participated in testing. Details here:

https://wiki.freebsd.org/projects/ifnet/net80211

Still, drivers: ndis, wtap, mwl, ipw, bwn, wi, upgt, uath were not
tested. Changes to mwl, ipw, bwn, wi, upgt are trivial and chances
of problems are low. The wtap wasn't compilable even before this change.
But the ndis driver is complex, and it is likely to be broken with this
commit. Help with testing and debugging it is appreciated.

Differential Revision:	D2655, D2740
Sponsored by:	Nginx, Inc.
Sponsored by:	Netflix
2015-08-07 11:43:14 +00:00
Adrian Chadd
52f5515397 Wake up the hardware before doing anything in sysctl.
This stops the panics that occur on MIPS platforms when doing say,
'sysctl dev.ath.0' whilst the MAC is asleep.  The MIPS platform is
rather unforgiving in getting power-save register access wrong and you
will get all kinds of odd failures if you don't have things woken
up at the right times.

Tested:

* QCA9558 (TP-Link Archer C7 v2)
* AR9331 (Carambola 2)

.. with no VAPs configured and ath0 down (thus the MAC is definitely
   asleep.)

PR:		kern/201117
2015-07-04 02:59:30 +00:00
Adrian Chadd
70bd9518f1 Bump the valid GPIO range for rfkill up from 8 to 16.
AR5416 and later NICs have more than 8 (Well, more than 6) GPIO pins.
So to support rfkill on these NICs we need to bump this up or the
rfkill GPIO pin may get reset to the wrong value.

Noticed by: Anthony Jenkins <scoobi_doo@yahoo.com>
2014-12-23 18:48:45 +00:00
Adrian Chadd
67aaf73997 Modify the RX path to keep the previous RX descriptor around once it's
used.

It turns out that the RX DMA engine does the same last-descriptor-link-
pointer-re-reading trick that the TX DMA engine.  That is, the hardware
re-reads the link pointer before it moves onto the next descriptor.
Thus we can't free a descriptor before we move on; it's possible the
hardware will need to re-read the link pointer before we overwrite
it with a new one.

Tested:

* AR5416, STA mode

TODO:

* more thorough AP and STA mode testing!
* test on other pre-AR9380 NICs, just to be sure.
* Break out the RX descriptor grabbing bits from the RX completion
  bits, like what is done in the RX EDMA code, so ..
* .. the RX lock can be held during ath_rx_proc(), but not across
  packet input.
2014-05-06 01:15:42 +00:00
Adrian Chadd
f5c30c4e8d Bring over some initial power save management support, reset path
fixes and beacon programming / debugging into the ath(4) driver.

The basic power save tracking:

* Add some new code to track the current desired powersave state; and
* Add some reference count tracking so we know when the NIC is awake; then
* Add code in all the points where we're about to touch the hardware and
  push it to force-wake.

Then, how things are moved into power save:

* Only move into network-sleep during a RUN->SLEEP transition;
* Force wake the hardware up everywhere that we're about to touch
  the hardware.

The net80211 stack takes care of doing RUN<->SLEEP<->(other) state
transitions so we don't have to do it in the driver.

Next, when to wake things up:

* In short - everywhere we touch the hardware.
* The hardware will take care of staying awake if things are queued
  in the transmit queue(s); it'll then transit down to sleep if
  there's nothing left.  This way we don't have to track the
  software / hardware transmit queue(s) and keep the hardware
  awake for those.

Then, some transmit path fixes that aren't related but useful:

* Force EAPOL frames to go out at the lowest rate.  This improves
  reliability during the encryption handshake after 802.11
  negotiation.

Next, some reset path fixes!

* Fix the overlap between reset and transmit pause so we don't
  transmit frames during a reset.
* Some noisy environments will end up taking a lot longer to reset
  than normal, so extend the reset period and drop the raise the
  reset interval to be more realistic and give the hardware some
  time to finish calibration.
* Skip calibration during the reset path.  Tsk!

Then, beacon fixes in station mode!

* Add a _lot_ more debugging in the station beacon reset path.
  This is all quite fluid right now.
* Modify the STA beacon programming code to try and take
  the TU gap between desired TSF and the target TU into
  account.  (Lifted from QCA.)

Tested:

* AR5210
* AR5211
* AR5212
* AR5413
* AR5416
* AR9280
* AR9285

TODO:

* More AP, IBSS, mesh, TDMA testing
* Thorough AR9380 and later testing!
* AR9160 and AR9287 testing

Obtained from:	QCA
2014-04-30 02:19:41 +00:00
Gleb Smirnoff
76039bc84f The r48589 promised to remove implicit inclusion of if_var.h soon. Prepare
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.
2013-10-26 17:58:36 +00:00
Adrian Chadd
72910f03e5 Implement a separate hardware queue threshold for aggregate and non-aggr
traffic.

When transmitting non-aggregate traffic, we need to keep the hardware
busy whilst transmitting or small bursts in txdone/tx latency will
kill us.

This restores non-aggregate iperf performance, especially when doing
TDMA.

Tested:

* AR5416<->AR5416, TDMA
* AR5416 STA <-> AR9280 AP
2013-05-21 18:13:57 +00:00
Adrian Chadd
2c47932c88 Implement STBC receive frame statistics.
The AR9280 and later can receive STBC.  This adds some statistics
tracking to count these frames.

A patch to athstats will be forthcoming.
2013-05-08 01:11:25 +00:00
Adrian Chadd
7dcb2bea01 Re-work how transmit buffer limits are enforced - partly to fix the PR,
but partly to just tidy up things.

The problem here - there are too many TX buffers in the queue! By the
time one needs to transmit an EAPOL frame (for this PR, it's the response
to the group rekey notification from the AP) there are no ath_buf entries
free and the EAPOL frame doesn't go out.

Now, the problem!

* Enforcing the TX buffer limitation _before_ we dequeue the frame?
  Bad idea. Because..
* .. it means I can't check whether the mbuf has M_EAPOL set.

The solution(s):

* De-queue the frame first
* Don't bother doing the TX buffer minimum free check until after
  we know whether it's an EAPOL frame or not.
* If it's an EAPOL frame, allocate the buffer from the mgmt pool
  rather than the default pool.

Whilst I'm here:

* Add a tweak to limit how many buffers a single node can acquire.
* Don't enforce that for EAPOL frames.
* .. set that to default to 1/4 of the available buffers, or 32,
  whichever is more sane.

This doesn't fix issues due to a sleeping node or a very poor performing
node; but this doesn't make it worse.

Tested:

* AR5416 STA, TX'ing 100+ mbit UDP to an AP, but only 50mbit being received
  (thus the TX queue fills up.)
* .. with CCMP / WPA2 encryption configured
* .. and the group rekey time set to 10 seconds, just to elicit the
  behaviour very quickly.

PR:		kern/138379
2013-05-07 07:52:18 +00:00
Adrian Chadd
b837332d0a Overhaul the TXQ locking (again!) as part of some beacon/cabq timing
related issues.

Moving the TX locking under one lock made things easier to progress on
but it had one important side-effect - it increased the latency when
handling CABQ setup when sending beacons.

This commit introduces a bunch of new changes and a few unrelated changs
that are just easier to lump in here.

The aim is to have the CABQ locking separate from other locking.
The CABQ transmit path in the beacon process thus doesn't have to grab
the general TX lock, reducing lock contention/latency and making it
more likely that we'll make the beacon TX timing.

The second half of this commit is the CABQ related setup changes needed
for sane looking EDMA CABQ support.  Right now the EDMA TX code naively
assumes that only one frame (MPDU or A-MPDU) is being pushed into each
FIFO slot.  For the CABQ this isn't true - a whole list of frames is
being pushed in - and thus CABQ handling breaks very quickly.

The aim here is to setup the CABQ list and then push _that list_ to
the hardware for transmission.  I can then extend the EDMA TX code
to stamp that list as being "one" FIFO entry (likely by tagging the
last buffer in that list as "FIFO END") so the EDMA TX completion code
correctly tracks things.

Major:

* Migrate the per-TXQ add/removal locking back to per-TXQ, rather than
  a single lock.

* Leave the software queue side of things under the ATH_TX_LOCK lock,
  (continuing) to serialise things as they are.

* Add a new function which is called whenever there's a beacon miss,
  to print out some debugging.  This is primarily designed to help
  me figure out if the beacon miss events are due to a noisy environment,
  issues with the PHY/MAC, or other.

* Move the CABQ setup/enable to occur _after_ all the VAPs have been
  looked at.  This means that for multiple VAPS in bursted mode, the
  CABQ gets primed once all VAPs are checked, rather than being primed
  on the first VAP and then having frames appended after this.

Minor:

* Add a (disabled) twiddle to let me enable/disable cabq traffic.
  It's primarily there to let me easily debug what's going on with beacon
  and CABQ setup/traffic; there's some DMA engine hangs which I'm finally
  trying to trace down.

* Clear bf_next when flushing frames; it should quieten some warnings
  that show up when a node goes away.

Tested:

* AR9280, STA/hostap, up to 4 vaps (staggered)
* AR5416, STA/hostap, up to 4 vaps (staggered)

TODO:

* (Lots) more AR9380 and later testing, as I may have missed something here.
* Leverage this to fix CABQ hanling for AR9380 and later chips.
* Force bursted beaconing on the chips that default to staggered beacons and
  ensure the CABQ stuff is all sane (eg, the MORE bits that aren't being
  correctly set when chaining descriptors.)
2013-03-24 00:03:12 +00:00
Adrian Chadd
1ab002f461 Print out the current fifo queue depth correctly - not just the max
queue depth.

Silly hat to me.
2013-03-18 02:29:57 +00:00
Adrian Chadd
eefc93a947 Dump out information about the RX descriptor free list and FIFO information. 2013-03-18 01:12:36 +00:00
Adrian Chadd
629ce2188a Implement "holding buffers" per TX queue rather than globally.
When working on TDMA, Sam Leffler found that the MAC DMA hardware
would re-read the last TX descriptor when getting ready to transmit
the next one.  Thus the whole ATH_BUF_BUSY came into existance -
the descriptor must be left alone (very specifically the link pointer
must be maintained) until the hardware has moved onto the next frame.

He saw this in TDMA because the MAC would be frequently stopping during
active transmit (ie, when it wasn't its turn to transmit.)

Fast-forward to today.  It turns out that this is a problem not with
a single MAC DMA instance, but with each QCU (from 0->9).  They each
maintain separate descriptor pointers and will re-read the last
descriptor when starting to transmit the next.

So when your AP is busy transmitting from multiple TX queues, you'll
(more) frequently see one QCU stopped, waiting for a higher-priority QCU
to finsh transmitting, before it'll go ahead and continue.  If you mess
up the descriptor (ie by freeing it) then you're short of luck.

Thanks to rpaulo for sticking with me whilst I diagnosed this issue
that he was quite reliably triggering in his environment.

This is a reimplementation; it doesn't have anything in common with
the ath9k or the Qualcomm Atheros reference driver.

Now - it in theory doesn't apply on the EDMA chips, as long as you
push one complete frame into the FIFO at a time.  But the MAC can DMA
from a list of frames pushed into the hardware queue (ie, you concat
'n' frames together with link pointers, and then push the head pointer
into the TXQ FIFO.)  Since that's likely how I'm going to implement
CABQ handling in hostap mode, it's likely that I will end up teaching
the EDMA TX completion code about busy buffers, just to be "sure"
this doesn't creep up.

Tested - iperf ap->sta and sta->ap (with both sides running this code):

* AR5416 STA
* AR9160/AR9220 hostap

To validate that it doesn't break the EDMA (FIFO) chips:

* AR9380, AR9485, AR9462 STA

Using iperf with the -S <tos byte decimal value> to set the TCP client
side DSCP bits, mapping to different TIDs and thus different TX queues.

TODO:

* Make this work on the EDMA chips, if we end up pushing lists of frames
  to the hardware (eg how we eventually will handle cabq in hostap/ibss
  mode.)
2013-03-14 06:20:02 +00:00
Adrian Chadd
a54ecf784a Add an option to allow the minimum number of delimiters to be tweaked.
This is primarily for debugging purposes.

Tested:

* AR5416, STA mode
2013-02-21 06:38:49 +00:00
Adrian Chadd
4a502c332a Add a new option to limit the maximum size of aggregates.
The default is to limit them to what the hardware is capable of.

Add sysctl twiddles for both the non-RTS and RTS protected aggregate
generation.

Whilst here, add some comments about stuff that I've discovered during
my exploration of the TX aggregate / delimiter setup path from the
reference driver.
2013-02-21 06:18:40 +00:00
Adrian Chadd
c5239edb98 Implement frame (data) transmission using if_transmit(), rather than
if_start().

This removes the overlapping data path TX from occuring, which
solves quite a number of the potential TX queue races in ath(4).
It doesn't fix the net80211 layer TX queue races and it doesn't
fix the raw TX path yet, but it's an important step towards this.

This hasn't dropped the TX performance in my testing; primarily
because now the TX path can quickly queue frames and continue
along processing.

This involves a few rather deep changes:

* Use the ath_buf as a queue placeholder for now, as we need to be
  able to support queuing a list of mbufs (ie, when transmitting
  fragments) and m_nextpkt can't be used here (because it's what is
  joining the fragments together)

* if_transmit() now simply allocates the ath_buf and queues it to
  a driver TX staging queue.

* TX is now moved into a taskqueue function.

* The TX taskqueue function now dequeues and transmits frames.

* Fragments are handled correctly here - as the current API passes
  the fragment list as one mbuf list (joined with m_nextpkt) through
  to the driver if_transmit().

* For the couple of places where ath_start() may be called (mostly
  from net80211 when starting the VAP up again), just reimplement
  it using the new enqueue and taskqueue methods.

What I don't like (about this work and the TX code in general):

* I'm using the same lock for the staging TX queue management and the
  actual TX.  This isn't required; I'm just being slack.

* I haven't yet moved TX to a separate taskqueue (but the taskqueue is
  created); it's easy enough to do this later if necessary.  I just need
  to make sure it's a higher priority queue, so TX has the same
  behaviour as it used to (where it would preempt existing RX..)

* I need to re-review the TX path a little more and make sure that
  ieee80211_node_*() functions aren't called within the TX lock.
  When queueing, I should just push failed frames into a queue and
  when I'm wrapping up the TX code, unlock the TX lock and
  call ieee80211_node_free() on each.

* It would be nice if I could hold the TX lock for the entire
  TX and TX completion, rather than this release/re-acquire behaviour.
  But that requires that I shuffle around the TX completion code
  to handle actual ath_buf free and net80211 callback/free outside
  of the TX lock.  That's one of my next projects.

* the ic_raw_xmit() path doesn't use this yet - so it still has
  sequencing problems with parallel, overlapping calls to the
  data path.  I'll fix this later.

Tested:

* Hostap - AR9280, AR9220
* STA - AR5212, AR9280, AR5416
2013-01-15 18:01:23 +00:00
Adrian Chadd
5f9fe65d64 Place 'dev.ath.X.debug' back under ATH_DEBUG, rather than ATH_DEBUG_ALQ. 2012-11-13 19:45:13 +00:00
Kevin Lo
f78d5b7e8a s/ATH_DEBUG/ATH_DEBUG_ALQ 2012-11-10 15:21:39 +00:00
Adrian Chadd
bbee93a84e Fix the build - fix up the ath_alq code to not compile by default. 2012-11-08 23:11:59 +00:00
Adrian Chadd
b69b0dcc24 Add some hooks into the driver to attach, detach and record EDMA descriptor
events.

This is primarily for the TX EDMA and TX EDMA completion. I haven't yet
tied it into the EDMA RX path or the legacy TX/RX path.

Things that I don't quite like:

* Make the pointer type 'void' in ath_softc and have if_ath_alq*()
  return a malloc'ed buffer.  That would remove the need to include
  if_ath_alq.h in if_athvar.h.
* The sysctl setup needs to be cleaned up.
2012-11-08 18:11:31 +00:00
Adrian Chadd
0368251456 Migrate the ath(4) KTR logging to use an ATH_KTR() macro.
This should eventually be unified with ATH_DEBUG() so I can get both
from one macro; that may take some time.

Add some new probes for TX and TX completion.
2012-09-24 20:35:56 +00:00
Adrian Chadd
f1bc738ece Implement my first cut at filtered frames in aggregation sessions.
The hardware can optionally "filter" frames if successive transmissions
to a given node (ie, "entry in the keycache") fail.  That way the hardware
can implement a kind of early abort of all the other frames queued to
that destination, rather than simply trying to TX each frame to that
destination (and failing.)

The background:

* If a frame comes back as being filtered, the hardware didn't try to
  TX it (or it was outside the TX burst opportunity.) So, take it as a hint
  that some (but not all, see below) frames to the destination may be
  filtered.

* If the CLRDMASK bit is set in a TX descriptor, the "filter to this
  destination" bit in the keycache entry is cleared and TX to that host
  will be unconditionally retried.

* Right now everything has the CLRDMASK bit set, so filtered frames
  tend to be aggregates and frames that fall outside of the WME burst
  window. It was a bit worse in the past as I had messed up the TX
  flags and CLRDMASK wasn't being set on aggregate frames.

The annoying bits:

* It's easy (ish) to do for aggregate session frames - firstly, they
  can be retried in any order as long as they're within the BAW, and
  there's already a bunch of infrastructure tracking how many frames
  the TID has queued to the hardware (tid->hwq_depth.) However, for
  frames that bypassed the software queue, hwq_depth doesn't get
  incremented. I'll fix that in a subsequent commit.

* For non-aggregate session frames, the only retries that can occur
  are ones for sequence numbers that hvaen't successfully been TXed yet.
  Since there's no re-ordering going on in non-aggregate sessions, if any
  subsequent seqno frames make it out, any filtered frames before that
  seqno need to be dropped.

  Hence why this initially is just for aggregate session frames.

* Since there may be intermediary frames to the destination that
  have CLRDMASK set - for example, any directly dispatched management
  frames to that destination - it's possible that there will be some
  filtered frames followed up by some non filtered frames.  Thus,
  it can't be assumed that once you see a filtered frame for the given
  destination node, all subsequent frames for all TIDs will be filtered.

Ok, with that in mind:

* Create a per-TID filtered frame queue for frames that the hardware
  returns as filtered.

* Track filtered frames per-tid, rather than per-node.  It just makes
  the locking much easier.

* When a filtered frame appears in the completion function, the node
  transitions to "filtered", and all subsequent completed error frames
  (filtered or otherwise) are put on the filtered frame queue.  The TID
  is paused once (during the transition from non-filtered to filtered).

* If a filtered frame retry count exceeds SWMAX_RETRIES, a BAR should be
  sent.

* Once all the frames queued to the hardware for the given filtered frame
  TID, transition back from filtered frame to non-filtered frame, which
  means pre-pending all the filtered frames onto the head of the software
  queue, clearing the filtered frame state and unpausing the TID.

Things get quite hairy around handling completion (aggr, non-aggr, norm,
direct-dispatched frames to a hardware queue); whether it's an "error",
"cleanup" or "BAR" state as well as filtered, which order to do things
in (eg do filtered BEFORE checking for BAR, as the filter completion
may be needed to actually transmit a BAR frame.)

This work has definitely reminded me that I have to tidy up all the locking
and remove some of the ridiculous lock/unlock/lock/unlock going on in the
completion functions.

It's also reminded me that I should really split out TID versus hardware TXQ
locking, even if the underlying locking is still the destination hardware TXQ.

Finally, this is all pre-requisite for working on AP mode power save support
(PS-POLL, uAPSD) as well as improving performance to misbehaving nodes (as
they can transition into filter mode, stopping any TX until everything has
caught up.)

Finally (ish) - this should also be done for non-aggregate sessions as
there are still plenty of laptops and mobile devices that don't speak
802.11n but do wish for stable, useful power save AP support where packets
aren't simply dropped.  This requires software retransmission for
non-aggregate sessions to be implemented, which includes the caveats I've
mentioned above.

Finally finally - this doesn't yet do anything about the CLRDMASK bit in the
TX descriptor.  That's still unconditionally set to 1.  I'll debug the
current work (mostly ensuring I haven't busted up the hairy transitions
between BAR, filtered, error (all frames in an aggregate failing) and
cleanup (when transitioning from aggregation -> non-aggregation.))

Finally finally finally - this is all original work by yours truely, rather
than ported from the Atheros internal driver codebase or Linux ath9k.

Tested:
 * AR9280, AR5416 in STA mode
 * AR9280, AR9130 in hostap mode
 * Lots and lots of iperf testing in very marginal and non-marginal conditions,
   complete with inducing filtered frames + BAR TX conditions.
2012-09-18 10:14:17 +00:00
Adrian Chadd
edd3e98f13 Dump out the TX FIFO depth. 2012-08-14 22:34:22 +00:00
Adrian Chadd
c7f5bb7a4f Handle RX Keymiss events.
The AR9003 series NICs implement a separate RX error to signal that a
Keycache miss occured.  The earlier NICs would not set the key index
valid bit.

I'll dig into the difference between "no key index bit set" and "keycache
miss".
2012-07-15 20:51:41 +00:00
Adrian Chadd
23ced6c117 Implement a global (all non-mgmt traffic) TX ath_buf limitation when
ath_start() is called.

This (defaults to 10 frames) gives for a little headway in the TX ath_buf
allocation, so buffer cloning is still possible.

This requires a lot omre experimenting and tuning.

It also doesn't stop a node/TID from consuming all of the available
ath_buf's, especially when the node is going through high packet loss
or only talking at a low TX rate.  It also doesn't stop a paused TID
from taking all of the ath_bufs.  I'll look at fixing that up in subsequent
commits.

PR:	kern/168170
2012-06-14 00:51:53 +00:00
Adrian Chadd
af33d486ab Implement a separate, smaller pool of ath_buf entries for use by management
traffic.

* Create sc_mgmt_txbuf and sc_mgmt_txdesc, initialise/free them appropriately.
* Create an enum to represent buffer types in the API.
* Extend ath_getbuf() and _ath_getbuf_locked() to take the above enum.
* Right now anything sent via ic_raw_xmit() allocates via ATH_BUFTYPE_MGMT.
  This may not be very useful.
* Add ATH_BUF_MGMT flag (ath_buf.bf_flags) which indicates the current buffer
  is a mgmt buffer and should go back onto the mgmt free list.
* Extend 'txagg' to include debugging output for both normal and mgmt txbufs.
* When checking/clearing ATH_BUF_BUSY, do it on both TX pools.

Tested:

* STA mode, with heavy UDP injection via iperf.  This filled the TX queue
  however BARs were still going out successfully.

TODO:

* Initialise the mgmt buffers with ATH_BUF_MGMT and then ensure the right
  type is being allocated and freed on the appropriate list.  That'd save
  a write operation (to bf->bf_flags) on each buffer alloc/free.

* Test on AP mode, ensure that BAR TX and probe responses go out nicely
  when the main TX queue is filled (eg with paused traffic to a TID,
  awaiting a BAR to complete.)

PR:		kern/168170
2012-06-13 06:57:55 +00:00
Adrian Chadd
0e22ed0eb2 Migrate ath_debug and sc_debug from an int to a uint64_t / QUAD;
add some more BAR debugging logic.

* Change the definition of ath_debug and ath_softc.sc_debug  from
  int to uint64_t;
* Change the relevant sysctls;
* Add a new BAR TX debugging field;
* Use this in if_ath_tx.

This has been tested by using the sysctl program, which happily allows
for fields > 32 bits to be configured.
2012-05-15 23:39:37 +00:00
Adrian Chadd
9467e3f3fc Squirrel away SYNC interrupt debugging if it's enabled in the HAL.
Bus errors will show up as various SYNC interrupts which will be passed
back up to ath_intr().
2012-04-10 07:23:37 +00:00
Adrian Chadd
e2e4a2c2a1 Break out the legacy duration and protection code into routines,
call these after rate control selection is done.

The duration/protection code wasn't working - it expected the rix to
be valid.  Unfortunately after I moved the rate control selection into
late in the process, the rix value isn't valid and thus the protection/
duration code would get things wrong.

HT frames are now correctly protected with an RTS and for the AR5416,
this involves having the aggregate frames be limited to 8K.

TODO:

* Fix up the DMA sync to occur just before the frame is queued to the
  hardware.  I'm adjusting the duration here but not doing the DMA
  flush.

* Doubly/triply ensure that the aggregate frames are being limited to
  the correct size, or the AR5416 will get unhappy when TXing RTS-protected
  aggregates.
2012-04-07 05:48:26 +00:00
Adrian Chadd
9c85ff9164 Don't flood the cabq/mcastq with frames.
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
2012-03-10 04:14:04 +00:00
Gavin Atkinson
1748d1e513 Correct capitalization of "Hz" in user-visible text (manpages, printf(),
etc).

MFC after:	3 days
2012-02-28 13:19:34 +00:00
Adrian Chadd
3440495a52 Flesh out configurable hardware based LED blinking.
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.
2011-12-26 07:47:05 +00:00
Adrian Chadd
6558ffd99a Refactor out the software LED config code into a common function, called
ath_led_config().

The eventual aim is to have both software and hardware based LED
configuration done here.
2011-12-26 05:46:22 +00:00
Adrian Chadd
2d3d4776cd Flesh out the TX aggregation completion statistics.
* 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.
2011-11-23 05:00:25 +00:00
Adrian Chadd
ddbe3036e5 Introduce a work-around for issues with the AR5416 based MAC on SMP devices.
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
2011-11-09 22:39:44 +00:00
Adrian Chadd
d3054f72e0 Add a new HAL parameter which forces a full reset rather than warm reset.
This forces a full reset of the baseband/radio and seems needed to clear
some issues (with Merlin at least) when the baseband gets confused in a
very noisy environment.

Sponsored by:	Hobnob, Inc.
2011-11-09 05:30:24 +00:00
Adrian Chadd
517526efe8 In preparation for supporting 11n TX/RX properly, allow for TX queue draining
and interface resets to be marked as ATH_RESET_DEFAULT, ATH_RESET_FULL,
ATH_RESET_NOLOSS.

Currently a reset is still a reset - ie, all tx/rx frames in the hardware
queues are purged. This means that those frames will be lost to the 11n TX
and RX aggregation state tracking, breaking AMPDU sessions.

The (eventual) new semantics:

* ATH_RESET_DEFAULT:
      full reset, this is the default for reset situations
      which I haven't yet figured out what they should be.
* ATH_RESET_FULL:
      A full reset - for things such as channel changes.
* ATH_RESET_NOLOSS:
      Don't flush TX/RX queues - handle pending RX frames and leave TX
      frames where they are; restart TX DMA from where it was.
2011-11-08 18:56:52 +00:00
Adrian Chadd
6b349e5a86 Migrate the STAILQ lists to TAILQs.
A bunch of the 11n TX aggregation logic wants to traverse lists of buffers
in various ways. In order to provide O(1) behaviour in this instance,
use TAILQs.

This does blow out the memory footprint and CPU cycles slightly for some
of these operations. I may convert some of these back to STAILQs once
the rest of the software transmit queue handling has been stabilised.

Sponsored by:	Hobnob, Inc.
2011-11-08 17:08:12 +00:00
Adrian Chadd
3dd85b265f Begin merging in some of my 802.11n TX aggregation driver changes.
* Add a PCU lock, which isn't currently used but will eventually be
  used to serialise some of the driver access.

* Add in all the software TX aggregation state, that's kept per-node
  and per-TID.

* Add in the software and aggregation state to ath_buf.

* Add in hooks to ath_softc for aggregation state and the (upcoming)
  aggregation TX state calls.

* Add / fix the HAL access macros.

Obtained from:	Linux, ath9k
Sponsored by:	Hobnob, Inc.
2011-11-08 02:12:11 +00:00
Adrian Chadd
b390e40af3 As a prelude to bringing over the 11n work, include some extra statistics fields. 2011-10-26 16:09:05 +00:00