ath(4): always enable 11n

Enabling 11n for ath(4) so far was handled by a kernel option, which
was only enabled for certain kernel configurations.
In order to allow loading ath(4) as a module with 1

ath(4): always enable 11n

Enabling 11n for ath(4) so far was handled by a kernel option, which
was only enabled for certain kernel configurations.
In order to allow loading ath(4) as a module with 11n support on
all platforms, remove the kernel option and unconditionally enable
11n in ath(4).

Reported by: pkubaj
Discussed with: adrian in D43549.
Reviewed by: adrian, imp
Differential Revision: https://reviews.freebsd.org/D43964

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sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

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[ath] Add ath_hal_getnav and ath_hal_setnav so the driver layer
can check the NAV as appropriate.

[ath] do a cold reset if TSFOOR triggers

TSFOOR happens if a beacon with a given TSF isn't received within the
programmed/expected TSF value, plus/minus a fudge range. (OOR == out of range.)

If thi

[ath] do a cold reset if TSFOOR triggers

TSFOOR happens if a beacon with a given TSF isn't received within the
programmed/expected TSF value, plus/minus a fudge range. (OOR == out of range.)

If this happens then it could be because the baseband/mac is stuck, or
the baseband is deaf. So, do a cold reset and resync the beacon to
try and unstick the hardware.

It also happens when a bad AP decides to err, slew its TSF because they
themselves are resetting and they don't preserve the TSF "well."

This has fixed a bunch of weird corner cases on my 2GHz AP radio upstairs
here where it occasionally goes deaf due to how much 2GHz noise is up
here (and ANI gets a little sideways) and this unsticks the station
VAP.

For AP modes a hung baseband/mac usually ends up as a stuck beacon
and those have been addressed for a long time by just resetting the
hardware. But similar hangs in station mode didn't have a similar
recovery mechanism.

Tested:

* AR9380, STA mode, 2GHz/5GHz
* AR9580, STA mode, 5GHz
* QCA9344 SoC w/ on-board wifi (TL-WDR4300/3600 devices); 2GHz
STA mode

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[ath] also remove the magic size value here for the transmit antenna statistics.

ath: clean up empty lines in .c and .h files

[ath] [ath_rate] Extend ath_rate_sample to better handle 11n rates and aggregates.

My initial rate control code was .. suboptimal. I wanted to at least get MCS
rates sent, but it didn't do anywhere

[ath] [ath_rate] Extend ath_rate_sample to better handle 11n rates and aggregates.

My initial rate control code was .. suboptimal. I wanted to at least get MCS
rates sent, but it didn't do anywhere near enough to handle low signal level links
or remotely keep accurate statistics.

So, 8 years later, here's what I should've done back then.

* Firstly, I wasn't at all tracking packet sizes other than the two buckets
(250 and 1600 bytes.) So, extend it to include 4096, 8192, 16384, 32768 and
65536. I may go add 2048 at some point if I find it's useful.

This is important for a few reasons. First, when forming A-MPDU or AMSDU
aggregates the frame sizes are larger, and thus the TX time calculation
is woefully, increasingly wrong. Secondly, the behaviour of 802.11 channels
isn't some fixed thing, both due to channel conditions and radios themselves.
Notably, there was some observations done a few years ago on 11n chipsets
which noticed longer aggregates showed an increase in failed A-MPDU sub-frame
reception as you got further along in the transmit time. It could be due to
a variety of things - transmitter linearity, channel conditions changing,
frequency/phase drift, etc - but the observation was to potentially form
shorter aggregates to improve BER.

* .. and then modify the ath TX path to report the length of the aggregate sent,
so as the statistics kept would line up with the correct bucket.

* Then on the rate control look-up side - i was also only using the first frame
length for an A-MPDU rate control lookup which isn't good enough here.
So, add a new method that walks the TID software queue for that node to
find out what the likely length of data available is. It isn't ALL of the
data in the queue because we'll only ever send enough data to fit inside the
block-ack window, so limit how many bytes we return to roughly what ath_tx_form_aggr()
would do.

* .. and cache that in the first ath_buf in the aggregate so it and the eventual
AMPDU length can be returned to the rate control code.

* THEN, modify the rate control code to look at them both when deciding which bucket
to attribute the sent frame on. I'm erring on the side of caution and using the
size bucket that the lookup is based on.

Ok, so now the rate lookups and statistics are "more correct". However, MCS rates
are not the same as 11abg rates in that they're not a monotonically incrementing
set of faster rates and you can't assume that just because a given MCS rate fails,
the next higher one wouldn't work better or be a lower average tx time.

So, I had to do a bunch of surgery to the best rate and sample rate math.
This is the bit that's a WIP.

* First, simplify the statistics updates (update_stats()) to do a single pass on
all rates.
* Next, make sure that each rate average tx time is updated based on /its/ failure/success.
Eg if you sent a frame with { MCS15, MCS12, MCS8 } and MCS8 succeeded, MCS15 and MCS
12 would have their average tx time updated for /their/ part of the transmission,
not the whole transmission.
* Next, EWMA wasn't being fully calculated based on the /failures/ in each of the
rate attempts. So, if MCS15, MCS12 failed above but MCS8 didn't, then ensure
that the statistics noted that /all/ subframes failed at those rates, rather than
the eventual set of transmitted/sent frames. This ensures the EWMA /and/ average
TX time are updated correctly.
* When picking a sample rate and initial rate, probe rates aroud the current MCS
but limit it to MCS0..7 /for all spatial streams/, rather than doing crazy things
like hitting MCS7 and then probing MCS8 - MCS8 is basically MCS0 but two spatial
streams. It's a /lot/ slower than MCS7. Also, the reverse is true - if we're at
MCS8 then don't probe MCS7 as part of it, it's not likely to succeed.
* Fix bugs in pick_best_rate() where I was /immediately/ choosing the highest MCS
rate if there weren't any frames yet transmitted. I was defaulting to 25% EWMA and
.. then each comparison would accept the higher rate. Just skip those; sampling
will fill in the details.

So, this seems to work a lot better. It's not perfect; I'm still seeing a lot of
instability around higher MCS rates because there are bursts of loss/retransmissions
that aren't /too/ bad. But i'll keep iterating over this and tidying up my hacks.

Ok, so why this still something I'm poking at? rather than porting minstrel_ht?

ath_rate_sample tries to minimise airtime, not maximise throughput. I have
extended it with an EWMA based on sub-frame success/failures - high MCS rates
that have partially successful receptions still show super short average frame
times, but a /lot/ of retransmits have to happen for that to work.
So for MCS rates I also track this EWMA and ensure that the rates I'm choosing
don't have super crappy packet failures. I don't mind not getting lower
peak throughput versus minstrel_ht; instead I want to see if I can make "minimise
airtime" work well.

Tested:

* AR9380, STA mode
* AR9344, STA mode
* AR9580, STA/AP mode

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MFHead @347527

Sponsored by: The FreeBSD Foundation

[ath] [ath_rate] Fix ANI calibration during non-ACTIVE states; start poking at rate control

These are some fun issues I've found with my upstairs wifi link at such a ridiculous
low signal level (lik

[ath] [ath_rate] Fix ANI calibration during non-ACTIVE states; start poking at rate control

These are some fun issues I've found with my upstairs wifi link at such a ridiculous
low signal level (like, < 5dB.)

* Add per-station tx/rx rssi statistics, in potential preparation to use that
in the RX rate control.

* Call the rate control on each received frame to let it potentially use
it as a hint for what rates to potentially use. It's a no-op right now.

* Do ANI calibration during scan as well. The ath_newstate() call was disabling the
ANI timer and only re-enabling it during transitions to _RUN. This has the
unfortunate side-effect that if ANI deafened the NIC because of interference
and it disassociated, it wouldn't be reset and the scan would never hear beacons.

The ANI configuration is stored at least globally on some HALs and per-channel
on others. Because of this a NIC reset wouldn't help; the ANI parameters would
simply be programmed back in.

Now, I have a feeling I also need to do this during AUTH/ASSOC too and maybe,
if I'm feeling clever, I need to reset the ANI parameters on a given channel
during a transition through INIT or if the VAP is destroyed/re-created.
However for now this gets me out of the immediate weeds with connectivity
upstairs (and thus I /can/ commit); I'll keep chipping away at tidying this
stuff up in subsequent commits.

Tested:

* AR9344 (Wasp), 2G STA mode

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[ath] [ath_hal] [ath_hal_9300] Extend the start PCU receive to handle resetting ANI.

One of the fun issues with scanning has been how the existing
ANI values were programmed into the hardware when c

[ath] [ath_hal] [ath_hal_9300] Extend the start PCU receive to handle resetting ANI.

One of the fun issues with scanning has been how the existing
ANI values were programmed into the hardware when channels were
changed. If you're on a really crappy channel and ANI has made
you deaf then when you scan you continue to be deaf on all channels.

This code passes in a flag to startpcureceive which in AR5416 and later
is also used to enable ANI. This allows it to know if it's a normal
operation or a scan operation.

This fixes my situation at home where a temporary spot of a device
going deaf due to interference starts scanning and .. can't hear
anything until I restart.

Now, this isn't the full fix - ideally:

(a) all the ANI config and per-channel information would be migrated
to the shared HAL stuff and enabled for all of the NICs;
(b) when a station reassociates and some other error conditions
(like missed beacons, NF calibration failures, etc) a knob
to reset ANI parameters would likely help recovery.

But hey, I'm committing bits of code again! woo!

Tested:

* AR9344 (2G), STA operation

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[ath] Fix return value check to not complain.

Compilers complain more about things, so let's keep them happy.

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

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.

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Merge ^/head r313301 through r313643.

MFhead@r313380

[ath] prepare for station side quiet time support.

* Track the current quiet time configuration in the ath_vap struct.
* Add an accessor method for calling the quiet time HAL method.

[ath] add a new buf flag, marking a buffer as involved with ToA/ToD positioning.

[ath] include ath_hal accessor macro changes.

I missed this in the previous commit.

[ath] fix comments!

I keep asking myself "what do these fields mean" and so now I've clarified
it for myself.

Tested:

* Reading the comments, going "a-ha!" a couple times.

Approved by: re (gjb)

[ath] commit initial bluetooth coexistence support for the MCI NICs.

This is the initial framework to call into the MCI HAL routines and drive
the basic state engine.

The MCI bluetooth coex model u

[ath] commit initial bluetooth coexistence support for the MCI NICs.

This is the initial framework to call into the MCI HAL routines and drive
the basic state engine.

The MCI bluetooth coex model uses a command channel between wlan and
bluetooth, rather than a 2-wire or 3-wire signaling protocol to control things.
This means the wlan and bluetooth chip exchange a lot more information and
signaling, even at the per-packet level. The NICs in question can share
the input LNA and output PA on the die, so they absolutely can't stomp
on each other in a silly fashion. It also allows for the bluetooth side
to signal when profiles come and go, so the driver can take appropriate
control. There's also the possibility of dynamic bluetooth/wlan duty cycle
control which I haven't yet really played with.

It configures things up with a static "wlan wins everything" coexistence,
configures up the available 2GHz channel map for bluetooth, sets a static
duty cycle for bluetooth/wifi traffic priority and drives the basics needed to
keep the MCI HAL code happy.

It doesn't do any actual coexistence except to default to "wlan wins everything",
which at least demonstrates that things do indeed work. Bluetooth inquiry frames
still trump wifi (including beacons), so that demonstrates things really do
indeed seem to work.

Tested:

* AR9462 (WB222), STA mode + bt
* QCA9565 (WB335), STA mode + bt

TODO:

* .. the rest of coexistence. yes, bluetooth, not people. That stuff's hard.
* It doesn't do the initial BT side calibration, which requires a WLAN chip
reset. I'll fix up the reset path a bit more first before I enable that.
* The 1-ant and 2-ant configuration bits aren't being set correctly in
if_ath_btcoex.c - I'll dig into that and fix it in a subsequent commit.
* It's not enabled by default for WB222/WB225 even though I believe it now
can be - I'll chase that up in a subsequent commit.

Obtained from: Qualcomm Atheros, Linux ath9k

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dev/ath: minor spelling fixes in comments.

No functional change.

Reviewed by: adrian

[ath] add LDPC capability support and LDPC RX support.

This enables LDPC receive support for the AR9300 chips that support it.
It'll announce LDPC support via net80211.

Tested:

* AR9380, STA mode

[ath] add LDPC capability support and LDPC RX support.

This enables LDPC receive support for the AR9300 chips that support it.
It'll announce LDPC support via net80211.

Tested:

* AR9380, STA mode
* AR9331, (to verify the HAL didn't attach it to a chip which
doesn't support LDPC.)

TODO:

* Add in net80211 machinery to make this configurable at runtime.

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MFH r289384-r293170

Sponsored by: The FreeBSD Foundation

Catch up with head (r291075).

ath(4): begin fleshing out a "reset type" extension to force cold/warn resets.

Right now the only way to force a cold reset is:

* The HAL itself detects it's needed, or
* The sysctl, setting all re

ath(4): begin fleshing out a "reset type" extension to force cold/warn resets.

Right now the only way to force a cold reset is:

* The HAL itself detects it's needed, or
* The sysctl, setting all resets to be cold.

Trouble is, cold resets take quite a bit longer than warm resets.

However, there are situations where a cold reset would be nice.
Specifically, after a stuck beacon, BB/MAC hang, stuck calibration results,
etc.

The vendor HAL has a separate method to set the reset reason (which is
how HAL_RESET_BBPANIC gets set) which informs the HAL during the reset path
why it occured. This is almost but not quite the same; I may eventually
unify both approaches in the future.

This commit just extends HAL_RESET_TYPE to include both status (eg BBPANIC)
and type (eg do COLD.) None of the HAL code uses it yet though; that'll
come later.

It also is a big no-op in each HAL - I need to go teach each of the HALs
about cold/warm reset through this path.

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