Commit Graph

544 Commits

Author SHA1 Message Date
Adrian Chadd
062cf7d90a Shut down RX before TX - in theory, this should make the chip less likely
to get upset.

The Qualcomm Atheros reference design code goes through significant
hacks to shut down RX before TX.  It doesn't even try do do it in the
driver - it actually makes the DMA stop routines in the HAL shut down
RX before shutting down TX.

So, to make this work for chips that aren't the AR9380 and later, do
it in the driver.  Shuffle the TX stop/drain HAL calls to be called
*after* the RX stop HAL call.

Tested:

* AR5413 (STA)
* AR5212 (STA)
* AR5416 (STA)
* AR9380 (STA)
* AR9331 (AP)
* AR9341 (AP)

TODO:

* test ar92xx series NIC and the AR5210/AR5211, in case there's something
  even odder about those.
2014-08-23 18:55:51 +00:00
Warner Losh
c737a387f5 an isn't used, so eliminate it. 2014-08-08 11:47:23 +00:00
Hans Petter Selasky
af3b2549c4 Pull in r267961 and r267973 again. Fix for issues reported will follow. 2014-06-28 03:56:17 +00:00
Glen Barber
37a107a407 Revert r267961, r267973:
These changes prevent sysctl(8) from returning proper output,
such as:

 1) no output from sysctl(8)
 2) erroneously returning ENOMEM with tools like truss(1)
    or uname(1)
 truss: can not get etype: Cannot allocate memory
2014-06-27 22:05:21 +00:00
Hans Petter Selasky
3da1cf1e88 Extend the meaning of the CTLFLAG_TUN flag to automatically check if
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.

Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.

MFC after:	2 weeks
Sponsored by:	Mellanox Technologies
2014-06-27 16:33:43 +00:00
Adrian Chadd
4b734a1c84 Wake up the hardware before calling ath_mode_init() in the ioctl() path.
Tested:

* AR5416, STA + powersave
2014-05-05 17:06:40 +00:00
Adrian Chadd
e5bd159ed5 Break out the multicast programming into its own hardware specific
call, which assumes the hardware is awake.

Turn ath_update_mcast() into a routine that's only called from the
net80211 layer - and it forces the hardware awake first.

This fixes a LOR from the EDMA RX path which calls ath_mode_init()
with the RX lock held - the driver lock can't also be grabbed.
This path assumes that the ath_mode_init() callers all wake up
the NIC first.

Tested:

* AR9485, STA mode, powersave
2014-05-05 08:12:21 +00:00
Adrian Chadd
7d567ed66f Add tracking for self-generated frames when the VAP is in sleep state.
The hardware can generate its own frames (eg RTS/CTS exchanges, other
kinds of 802.11 management stuff, especially when it comes to 802.11n)
and these also have PWRMGT flags.  So if the VAP is asleep but the
NIC is in force-awake for some reason, ensure that the self-generated
frames have PWRMGT set to 1.

Now, this (like basically everything to do with powersave) is still
racy - the only way to guarantee that it's all actually consistent
is to pause transmit and let it finish before transitioning the VAP
to sleep, but this at least gets the basic method of tracking and
updating the state debugged.

Tested:

* AR5416, STA mode
* AR9380, STA mode
2014-05-02 00:48:09 +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
Adrian Chadd
656380e725 Wrap the rate control re-init code in a lock, to serialise it with
concurrent updates from any completing transmits in other threads.

This was exposed when doing power save work - net80211 is constantly
doing reassociations and it's causing the rate control state to get
blanked out.  This could cause the rate control code to assert.

This should be MFCed to stable/10 as it's a stability fix.

Tested:

* AR5416, STA

MFC after:	7 days
2014-04-23 05:19:45 +00:00
Adrian Chadd
410302eb58 Don't call ath_init() inside the lock.
Yes, this means that sc_invalid is slightly racy, but there are other
issues here which need fixing.

This fixes a source of eventual LORs - ath_init() grabs ATH_LOCK to do
work and releases it before it calls ieee80211_start_all().
ieee80211_start_all() will grab the net80211 comlock to iterate over
the VAPs.

TODO:

* .. I should just migrate the ieee80211_start_all() work to a
  deferred task so it can be done later; it doesn't have to be
  immediately done.

Tested:

* AR5416, STA mode
2014-03-20 04:47:34 +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
Rui Paulo
83bbd5ebf9 Move a lot of debugging printf's to DPRINTF.
Approved by:	adrian
MFC after:	2 weeks
2013-10-17 01:53:07 +00:00
Adrian Chadd
e95f34242c Use the new ieee80211_tx_complete() function. 2013-08-27 14:39:37 +00:00
Adrian Chadd
216ca2346f Migrate the LNA mixing diversity machinery from the AR9285 HAL to the driver.
The AR9485 chip and AR933x SoC both implement LNA diversity.
There are a few extra things that need to happen before this can be
flipped on for those chips (mostly to do with setting up the different
bias values and LNA1/LNA2 RSSI differences) but the first stage is
putting this code into the driver layer so it can be reused.

This has the added benefit of making it easier to expose configuration
options and diagnostic information via the ioctl API.  That's not yet
being done but it sure would be nice to do so.

Tested:

* AR9285, with LNA diversity enabled
* AR9285, with LNA diversity disabled in EEPROM
2013-06-12 14:52:57 +00:00
Adrian Chadd
b70f530bc7 Bring over the initial static bluetooth coexistence configuration
for the WB195 combo NIC - an AR9285 w/ an AR3011 USB bluetooth NIC.

The AR3011 is wired up using a 3-wire coexistence scheme to the AR9285.

The code in if_ath_btcoex.c sets up the initial hardware mapping
and coexistence configuration.  There's nothing special about it -
it's static; it doesn't try to configure bluetooth / MAC traffic priorities
or try to figure out what's actually going on.  It's enough to stop basic
bluetooth traffic from causing traffic stalls and diassociation from
the wireless network.

To use this code, you must have the above NIC.  No, it won't work
for the AR9287+AR3012, nor the AR9485, AR9462 or AR955x combo cards.

Then you set a kernel hint before boot or before kldload, where 'X'
is the unit number of your AR9285 NIC:

# kenv hint.ath.X.btcoex_profile=wb195

This will then appear in your boot messages:

[100482] athX: Enabling WB195 BTCOEX

This code is going to evolve pretty quickly (well, depending upon my
spare time) so don't assume the btcoex API is going to stay stable.

In order to use the bluetooth side, you must also load in firmware using
ath3kfw and the binary firmware file (ath3k-1.fw in my case.)

Tested:

* AR9280, no interference
* WB195 - AR9285 + AR3011 combo; STA mode; basic bluetooth inquiries
  were enough to cause traffic stalls and disassociations.  This has
  stopped with the btcoex profile code.

TODO:

* Importantly - the AR9285 needs ASPM disabled if bluetooth coexistence
  is enabled.  No, I don't know why.  It's likely some kind of bug to do
  with the AR3011 sending bluetooth coexistence signals whilst the device
  is asleep.  Since we don't actually sleep the MAC just yet, it shouldn't
  be a problem.  That said, to be totally correct:

  + ASPM should be disabled - upon attach and wakeup
  + The PCIe powersave HAL code should never be called

  Look at what the ath9k driver does for inspiration.

* Add WB197 (AR9287+AR3012) support
* Add support for the AR9485, which is another combo like the AR9285
* The later NICs have a different signaling mechanism between the MAC
  and the bluetooth device; I haven't even begun to experiment with
  making that HAL code work.  But it should be a lot more automatic.

* The hardware can do much more interesting traffic weighting with
  bluetooth and wifi traffic.  None of this is currently used.
  Ideally someone would code up something to watch the bluetooth traffic
  GPIO (via an interrupt) and then watch it go high/low; then figure out
  what the bluetooth traffic is and adjust things appropriately.

* If I get the time I may add in some code to at least track this stuff
  and expose statistics.  But it's up to someone else to experiment with
  the bluetooth coexistence support and add the interesting stuff (like
  "real" detection of bulk, audio, etc bluetooth traffic patterns and
  change wifi parameters appropriately - eg, maximum aggregate length,
  transmit power, using quiet time to control TX duty cycle, etc.)
2013-06-07 09:02:02 +00:00
Adrian Chadd
3df7a8ab08 Implement a bit of a hack to store the AR9285/AR9485 RX LNA configuration in
the RX antenna field.

The AR9285/AR9485 use an LNA mixer to determine how to combine the signals
from the two antennas.  This is encoded in the RSSI fields (ctl/ext) for
chain 2.  So, let's use that here.

This maps RX antennas 0->3 to the RX mixer configuration used to
receive a frame.  There's more that can be done but this is good enough
to diagnose if the hardware is doing "odd" things like trying to
receive frames on LNA2 (ie, antenna 2 or "alt" antenna) when there's
only one antenna connected.

Tested:

* AR9285, STA mode
2013-06-05 00:45:19 +00:00
Adrian Chadd
904e385eba Fix the order of TX shutdown and reset.
* Grab the reset lock first, so any subsequent interrupt, TX, RX work
  will fail

* Then shut down interrupts

* Then wait for TX/RX to finish running

At this point no further work will be running, so it's safe to do the
reset path code.

PR:		kern/179232
2013-06-03 19:39:37 +00:00
Adrian Chadd
32da86a0f1 Turn the reassociate debug print into a DPRINTF. 2013-05-29 05:10:11 +00:00
Adrian Chadd
cd7dffd058 Migrate ath(4) to now use if_transmit instead of the legacy if_start
and if queue mechanism; also fix up (non-11n) TX fragment handling.

This may result in a bit of a performance drop for now but I plan on
debugging and resolving this at a later stage.

Whilst here, fix the transmit path so fragment transmission works.

The TX fragmentation handling is a bit more special.  In order to
correctly transmit TX fragments, there's a bunch of corner cases that
need to be handled:

* They must be transmitted back to back, in the same order..
* .. ie, you need to hold the TX lock whilst transmitting this
  set of fragments rather than interleaving it with other MSDUs
  destined to other nodes;
* The length of the next fragment is required when transmitting, in
  order to correctly set the NAV field in the current frame to the
  length of the next frame; which requires ..
* .. that we know the transmit duration of the next frame, which ..
* .. requires us to set the rate of all fragments to the same length,
  or make the decision up-front, etc.

To facilitate this, I've added a new ath_buf field to describe the
length of the next fragment.  This avoids having to keep the mbuf
chain together.  This used to work before my 11n TX path work because
the ath_tx_start() routine would be handed a single mbuf with m_nextpkt
pointing to the next frame, and that would be maintained all the way
up to when the duration calculation was done.  This doesn't hold
true any longer - the actual queuing may occur at any point in the
future (think ath_node TID software queuing) so this information
needs to be maintained.

Right now this does work for non-11n frames but it doesn't at all
enforce the same rate control decision for all frames in the fragment.
I plan on fixing this in a followup commit.

RTS/CTS has the same issue, I'll look at fixing this in a subsequent
commit.

Finaly, 11n fragment support requires the driver to have fully
decided what the rate scenario setup is - including 20/40MHz,
short/long GI, STBC, LDPC, number of streams, etc.  Right now that
decision is (currently) made _after_ the NAV field value is updated.
I'll fix all of this in subsequent commits.

Tested:

* AR5416, STA, transmitting 11abg fragments
* AR5416, STA, 11n fragments work but the NAV field is incorrect for
  the reasons above.

TODO:

* It would be nice to be able to queue mbufs per-node and per-TID so
  we can only queue ath_buf entries when it's time to assemble frames
  to send to the hardware.

  But honestly, we should just do that level of software queue management
  in net80211 rather than ath(4), so I'm going to leave this alone for now.

* More thorough AP, mesh and adhoc testing.

* Ensure that net80211 doesn't hand us fragmented frames when A-MPDU has
  been negotiated, as we can't do software retransmission of fragments.

* .. set CLRDMASK when transmitting fragments, just to ensure.
2013-05-26 22:23:39 +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
dd6a574e09 Enable the use of TDMA on an 802.11n channel (with aggregation disabled,
of course.)

There's a few things that needed to happen:

* In case someone decides to set the beacon transmission rate to be
  at an MCS rate, use the MCS-aware version of the duration calculation
  to figure out how long the received beacon frame was.

* If TxOP enforcing is available on the hardware and we're doing TDMA,
  enable it after a reset and set the TDMA guard interval to zero.
  This seems to behave fine.

TODO:

* Although I haven't yet seen packet loss, the PHY errors that would be
  triggered (specifically Transmit-Override-Receive) aren't enabled
  by the 11n HAL.  I'll have to do some work to enable these PHY errors
  for debugging.

What broke:

* My recent changes to the TX queue handling has resulted in the driver
  not keeping the hardware queue properly filled when doing non-aggregate
  traffic.  I have a patch to commit soon which fixes this situation
  (albeit by reminding me about how my ath driver locking isn't working
  out, sigh.)

  So if you want to test this without updating to the next set of patches
  that I commit, just bump the sysctl dev.ath.X.hwq_limit from 2 to 32.

Tested:

* AR5416 <-> AR5416, with ampdu disabled, HT40, 5GHz, MCS12+Short-GI.
  I saw 30mbit/sec in both directions using a bidirectional UDP test.
2013-05-21 18:02:54 +00:00
Adrian Chadd
bd0edcac7c Since we're now using the ah pointer, always declare it.
This fixes non-DEBUG builds.
2013-05-19 00:53:06 +00:00
Adrian Chadd
9be82a4209 Be (very) careful about how to add more TX DMA work.
The list-based DMA engine has the following behaviour:

* When the DMA engine is in the init state, you can write the first
  descriptor address to the QCU TxDP register and it will work.

* Then when it hits the end of the list (ie, it either hits a NULL
  link pointer, OR it hits a descriptor with VEOL set) the QCU
  stops, and the TxDP points to the last descriptor that was transmitted.

* Then when you want to transmit a new frame, you can then either:
  + write the head of the new list into TxDP, or
  + you write the head of the new list into the link pointer of the
    last completed descriptor (ie, where TxDP points), then kick
    TxE to restart transmission on that QCU>

* The hardware then will re-read the descriptor to pick up the link
  pointer and then jump to that.

Now, the quirks:

* If you write a TxDP when there's been no previous TxDP (ie, it's 0),
  it works.

* If you write a TxDP in any other instance, the TxDP write may actually
  fail.  Thus, when you start transmission, it will re-read the last
  transmitted descriptor to get the link pointer, NOT just start a new
  transmission.

So the correct thing to do here is:

* ALWAYS use the holding descriptor (ie, the last transmitted descriptor
  that we've kept safe) and use the link pointer in _THAT_ to transmit
  the next frame.

* NEVER write to the TxDP after you've done the initial write.

* .. also, don't do this whilst you're also resetting the NIC.

With this in mind, the following patch does basically the above.

* Since this encapsulates Sam's issues with the QCU behaviour w/ TDMA,
  kill the TDMA special case and replace it with the above.

* Add a new TXQ flag - PUTRUNNING - which indicates that we've started
  DMA.

* Clear that flag when DMA has been shutdown.

* Ensure that we're not restarting DMA with PUTRUNNING enabled.

* Fix the link pointer logic during TXQ drain - we should always ensure
  the link pointer does point to something if there's a list of frames.
  Having it be NULL as an indication that DMA has finished or during
  a reset causes trouble.

Now, given all of this, i want to nuke axq_link from orbit.  There's now HAL
methods to get and set the link pointer of a descriptor, so what we
should do instead is to update the right link pointer.

* If there's a holding descriptor and an empty TXQ list, set the
  link pointer of said holding descriptor to the new frame.

* If there's a non-empty TXQ list, set the link pointer of the
  last descriptor in the list to the new frame.

* Nuke axq_link from orbit.

Note:

* The AR9380 doesn't need this.  FIFO TX writes are atomic.  As long as
  we don't append to a list of frames that we've already passed to the
  hardware, all of the above doesn't apply.  The holding descriptor stuff
  is still needed to ensure the hardware can re-read a completed
  descriptor to move onto the next one, but we restart DMA by pushing in
  a new FIFO entry into the TX QCU.  That doesn't require any real
  gymnastics.

Tested:

* AR5210, AR5211, AR5212, AR5416, AR9380 - STA mode.
2013-05-18 18:27:53 +00:00
Adrian Chadd
f2f6761490 Re-add some code to exclude transmitting if we're in reset.
This fixes some "transmitting during reset" bugs that crept in after
I messed around with this part of the transmit path.
2013-05-18 13:58:07 +00:00
Adrian Chadd
dfaf8de927 Dump out the holding buffer descriptor contents and addresses stopping DMA. 2013-05-16 17:45:01 +00:00
Adrian Chadd
22a3aee637 Implement my first cut at "correct" node power-save and
PS-POLL support.

This implements PS-POLL awareness i nthe

* Implement frame "leaking", which allows for a software queue
  to be scheduled even though it's asleep
* Track whether a frame has been leaked or not
* Leak out a single non-AMPDU frame when transmitting aggregates
* Queue BAR frames if the node is asleep
* Direct-dispatch the rest of control and management frames.
  This allows for things like re-association to occur (which involves
  sending probe req/resp as well as assoc request/response) when
  the node is asleep and then tries reassociating.
* Limit how many frames can set in the software node queue whilst
  the node is asleep.  net80211 is already buffering frames for us
  so this is mostly just paranoia.
* Add a PS-POLL method which leaks out a frame if there's something
  in the software queue, else it calls net80211's ps-poll routine.
  Since the ath PS-POLL routine marks the node as having a single frame
  to leak, either a software queued frame would leak, OR the next queued
  frame would leak. The next queued frame could be something from the
  net80211 power save queue, OR it could be a NULL frame from net80211.

TODO:

* Don't transmit further BAR frames (eg via a timeout) if the node is
  currently asleep.  Otherwise we may end up exhausting management frames
  due to the lots of queued BAR frames.

  I may just undo this bit later on and direct-dispatch BAR frames
  even if the node is asleep.

* It would be nice to burst out a single A-MPDU frame if both ends
  support this.  I may end adding a FreeBSD IE soon to negotiate
  this power save behaviour.

* I should make STAs timeout of power save mode if they've been in power
  save for more than a handful of seconds.  This way cards that get
  "stuck" in power save mode don't stay there for the "inactivity" timeout
  in net80211.

* Move the queue depth check into the driver layer (ath_start / ath_transmit)
  rather than doing it in the TX path.

* There could be some naughty corner cases with ps-poll leaking.
  Specifically, if net80211 generates a NULL data frame whilst another
  transmitter sends a normal data frame out net80211 output / transmit,
  we need to ensure that the NULL data frame goes out first.
  This is one of those things that should occur inside the VAP/ic TX lock.
  Grr, more investigations to do..

Tested:

* STA: AR5416, AR9280
* AP: AR5416, AR9280, AR9160
2013-05-15 18:33:05 +00:00
Adrian Chadd
370f81fab6 Add ALQ beacon debugging. 2013-05-13 21:18:00 +00:00
Adrian Chadd
9b48fb4b32 Improve the debugging output - use the MAC address rather than various
pointer values everywhere.
2013-05-13 19:52:35 +00:00
Adrian Chadd
ba83edd45c Since the node state is 100% back under the TX lock, just kill the use
of atomics.

I'll re-think this nonsense later.
2013-05-13 19:03:12 +00:00
Adrian Chadd
4bed2b67ca Begin tidying up the reassociation and node sleep/wakeup paths.
* Move the node sleep/wake state under the TX lock rather than the
  node lock.  Let's leave the node lock protecting rate control only
  for now.

* When reassociating, various state needs to be cleared.  For example,
  the aggregate session needs to be torn down, including any pending
  aggregation negotiation and BAR TX waiting.

* .. and we need to do a "cleanup" pass since frames in the hardware
  TX queue need to be transmitted.

Modify ath_tx_tid_cleanup() to be called with the TX lock held and push
frames into a completion list.  This allows for the cleanup to be
done atomically for all TIDs in a node rather than grabbing and
releasing the TX lock each time.
2013-05-13 18:56:04 +00:00
Adrian Chadd
8328d6e4d4 Make sure the holding descriptor and link pointer are both freed during
a non-loss reset.

When the drain functions are called, the holding descriptor and link pointers
are NULLed out.

But when the processq function is called during a non-loss reset, this
doesn't occur.  So the next time a DMA occurs, it's chained to a descriptor
that no longer exists and the hardware gets angry.

Tested:

* AR5416, STA mode; use sysctl dev.ath.X.forcebstuck=1 to force a non-loss
  reset.

TODO:

* Further AR9380 testing just to check that the behaviour for the EDMA
  chips is sane.

PR:		kern/178477
2013-05-10 10:06:45 +00:00
Adrian Chadd
5e0185081d Fix the holding descriptor logic to actually be "right" (for values
of "right".)

Flip back on the "always continue TX DMA using the holding descriptor"
code - by always setting ATH_BUF_BUSY and never setting axq_link to NULL.

Since the holding descriptor is accessed via txq->axq_link and _that_
is done behind the TXQ lock rather than the TX path lock, the holding
descriptor stuff itself needs to be behind the TXQ lock.

So, do the mental gymnastics needed to do this.

I've not seen any of the hardware failures that I was seeing when
I last tried to do this.

Tested:

* AR5416, STA mode
2013-05-08 21:23:51 +00:00
Adrian Chadd
d3731e4b21 Revert a previous commit - this is causing hardware errors.
I'm not sure why this is failing.  The holding descriptor should be being
re-read when starting DMA of the next frame.  Obviously something here
isn't totally correct.

I'll review the TX queue handling and see if I can figure out why this
is failing.  I'll then re-revert this patch out and use the holding
descriptor again.
2013-05-08 07:30:33 +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
4136c09143 The holding buffer logic needs to be used for _all_ transmission, not
just "when the queue is busy."

After talking with the MAC team, it turns out that the linked list
implementation sometimes will not accept a TxDP update and will
instead re-read the link pointer.  So even if the hardware has
finished transmitting a chain and has hit EOL/VEOL, it may still
re-read the link pointer to begin transmitting again.

So, always set ATH_BUF_BUSY on the last buffer in the chain (to
mark the last descriptor as the holding descriptor) and never
blank the axq_link pointer.

Tested:

* AR5416, STA mode

TODO:

* much more thorough testing with the pre-11n NICs, just to verify
  that they behave the same way.
* test TDMA on the 11n and non-11n hardware.
2013-05-04 04:03:50 +00:00
Adrian Chadd
8d06054291 Debugging changes!
* That lock isn't actually held during reset - just the whole TX/RX path
  is paused.  So, remove the assertion.

* Log the TX queue status - how many hardware frames are active in the
  MAC and whether the queue is active.
2013-04-29 07:28:29 +00:00
Adrian Chadd
07187d1109 Conditionally compile this only if ATH_DEBUG is defined. 2013-04-26 22:22:38 +00:00
Adrian Chadd
ed261a611b Dump the entire TXQ descriptor contents during a reset, rather than only
completed descriptors.
2013-04-26 21:51:17 +00:00
Adrian Chadd
ff5b563430 Initialise the chainmask fields regardless of whether 11n support
is compiled in or not.

This fixes issues with people running -HEAD but who build modules
without doing a "make buildkernel KERNCONF=XXX", thus picking up
opt_*.h.  The resulting module wouldn't have 11n enabled and the
chainmask configuration would just be plain wrong.
2013-04-19 21:49:11 +00:00
Adrian Chadd
7904f51655 Add a debug statement to log the currently chosen chainmask configuration. 2013-04-19 08:06:45 +00:00
Adrian Chadd
b0bf95ff15 .. don't know how this snuck into this commit. Sorry.
Fix compile build before anyone notices.
2013-04-19 08:01:34 +00:00
Adrian Chadd
b661bd2e52 Print out the chainmask configuration. 2013-04-19 07:56:22 +00:00
Adrian Chadd
6f4fb2d8e6 Use uint32_t for fields that are fetched via ath_hal_getcapability(). 2013-04-19 06:59:10 +00:00
Adrian Chadd
5d4dedadb6 Use a per-RX-queue deferred list, rather than a single deferred list for
both queues.

Since ath_rx_pkt() does multi-mbuf frame recombining based on the RX queue,
this needs to occur.

Tested:

* AR9380 (XB112), hostap mode
2013-04-16 20:21:02 +00:00
Adrian Chadd
6961e9eda4 Always enable TXOK interrupts when setting up TX queues for EDMA NICs. 2013-04-11 22:02:35 +00:00
Adrian Chadd
a91ab3c099 Some TX dmamap cleanups.
* Don't use BUS_DMA_ALLOCNOW for descriptor DMA maps; we never use
  bounce buffers for the descriptors themselves.

* Add some XXX's to mark where the ath_buf has its mbuf ripped from
  underneath it without actually cleaning up the dmamap.  I haven't
  audited those particular code paths to see if the DMA map is guaranteed
  to be setup there; I'll do that later.

* Print out a warning if the descdma tidyup code is given some descriptors
  w/ maps to free.  Ideally the owner will free the mbufs and unmap
  the descriptors before freeing the descriptor/ath_buf pairs, but
  right now that's not guaranteed to be done.

Reviewed by:	scottl (BUS_DMA_ALLOCNOW tag)
2013-04-02 06:24:22 +00:00
Adrian Chadd
3f3a5dbd2c Ensure that we only call the busdma unmap/flush routines once, when
the buffer is being freed.

* When buffers are cloned, the original mapping isn't copied but it
  wasn't freeing the mapping until later.  To be safe, free the
  mapping when the buffer is cloned.

* ath_freebuf() now no longer calls the busdma sync/unmap routines.

* ath_tx_freebuf() now calls sync/unmap.

* Call sync first, before calling unmap.

Tested:

* AR5416, STA mode
2013-04-01 20:57:13 +00:00
Adrian Chadd
587feafb5a Remove an un-needed comment. 2013-04-01 20:44:21 +00:00
Adrian Chadd
09067b6e9a Use ATH_MAX_SCATTER rather than ATH_TXDESC.
ATH_MAX_SCATTER is used to size the ath_buf DMA segment array.
We thus should use it when checking sizes of things.
2013-04-01 20:12:21 +00:00