The recent cleanups in the beacon code fixed SWBA backoff calculation,
however it did not remove a line of code that worked around the issues
from the earlier version of the code.
After the cleanup, the initial TSF based slot calculation now always
returns 0 instead of ATH_BCBUF-1, so the previous hack that reversed the
slot order needs to be removed, as ad-hoc mode does not use staggered
beacons.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Stuck beacon detection is supposed to trigger when 9 consecutive beacons
could not be sent by the hardware. When the driver runs only one active
AP mode interface, it still configures the hardware beacon timer for
4 (ATH_BCBUF) beacon slots slots, which causes stuck beacon detection
to be reset if ath9k_hw_stoptxdma clears the stuck frames between
SWBA intervals.
Fix this by not resetting the missed beacon count for empty slots and
multiplying the threshold not by the maximum number of beacon slots
but by the configured number of beacon interfaces.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Single missed (i.e. not transmitted) beacons in AP mode are not very rare
and not necessarily an indicator of strong interference, so only trigger
noise floor recalibration when multiple consecutive beacons could not
be transmitted.
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

AP mode beacon timers in ath9k are configured in milliseconds, which breaks
when increasing ATH_BCBUF to 8 instead of 4 (due to rounding errors).
Since the hardware timers are actually configured in microseconds, it's
better to let the driver use that unit directly.

To be able to do that, the beacon interval parameter abuse for passing
certain flags needs to be removed. This is easy to do, because those flags
are completely unnecessary anyway. ATH9K_BEACON_ENA is ignored,
ATH9K_BEACON_RESET_TSF can be replaced with calling ath9k_hw_reset_tsf
from the driver directly.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ath9k calls ath9k_hw_stoptxdma every time it sends a beacon, however there
is not much point in doing that if the previous beacon and mcast traffic
went out properly. On AR9380, calling that function too often can result
in an increase of stuck beacons due to differences in the handling of the
queue enable/disable functionality.

With this patch, the queue will only be explicitly stopped if the previous
data frames were not sent successfully. With the beacon code being the
only remaining user of ath9k_hw_stoptxdma, this function can be simplified
in order to remove the now pointless attempts at waiting for transmission
completion, which would never happen at this point due to the different
method of tx scheduling of the beacon queue.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Beaconing should be disabled before stopping beacon queue.
Not doing so could queue up beacons in hw that causes
failure to stop Tx DMA, due to pending frames in hw
and also unnecessary beacon tasklet schedule.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The variable appears in both ath_softc and ath_beacon_config.
The struct ath_beacon_config is embedded in ath_softc. The redundant
variable was added by commit id 57c4d7b4.
Signed-off-by: NSteve Brown <sbrown@cortland.com>
Reviewed-by: NMohammed Shafi <shafi.ath9k@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add few comments for not parsing DTIM period from mac80211
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When beacons are being added or removed for an interface, ieee80211_beacon_get
will sometimes not return a beacon. This is normal and should not result in
useless logspam.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When using a mixture of AP and Station interfaces,
the hardware mode was using the type of the
last VIF registered.  Instead, we should keep track
of the number of different types of vifs and set the
mode accordingly.

In addtion, use the vif type instead of hardware opmode
when dealing with beacons.

Attempt to move some of the common setup code into smaller
methods so we can re-use it when changing vif mode as
well as adding/deleting vifs.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some minor clean ups in assigning values to beacon config parameters
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Remove ath/debug.h and the includes of these files.
Coalesce long formats.
Correct a few misspellings and missing "\n"s from these logging messages.
Remove unnecessary trailing space before a newline.
Remove ARRAY_SIZE casts, use printf type %zu
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

So these errors are always emitted at KERN_ERR level.
Remove ARRAY_SIZE casts, use printf type %zu
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This feature is to mitigate the problem of certain 3
stream chips that exceed the PCIe power requirements.An EEPROM flag
controls which chips have APM enabled which is basically read from
miscellaneous configuration element of the EEPROM header.

This workaround will reduce power consumption by using 2 Tx chains for
Single and Double stream rates (5 GHz only).All self generated frames
(regardless of rate) are sent on 2 chains when this feature is
enabled(Chip Limitation).

Cc: Paul Shaw <paul.shaw@atheros.com>
Signed-off-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Tested-by: NMohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Merge initial processing for the CAB queue and regular tx.
Also move ath_tx_cabq() to beacon.c and make it static.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The current ath9k tx queue handling code showed a few issues that could
lead to locking issues, tx stalls due to stopped queues, and maybe even
DMA issues.

The main source of these issues is that in some places the queue is
selected via skb queue mapping in places where this mapping may no
longer be valid. One such place is when data frames are transmitted via
the CAB queue (for powersave buffered frames). This is made even worse
by a lookup WMM AC values from the assigned tx queue (which is
undefined for the CAB queue).

This messed up the pending frame counting, which in turn caused issues
with queues getting stopped, but not woken again.

To fix these issues, this patch removes an unnecessary abstraction
separating a driver internal queue number from the skb queue number
(not to be confused with the hardware queue number).

It seems that this abstraction may have been necessary because of tx
queue preinitialization from the initvals. This patch avoids breakage
here by pushing the software <-> hardware queue mapping to the function
that assigns the tx queues and redefining the WMM AC definitions to
match the numbers used by mac80211 (also affects ath9k_htc).

To ensure consistency wrt. pending frame count tracking, these counters
are moved to the ath_txq struct, updated with the txq lock held, but
only where the tx queue selected by the skb queue map actually matches
the tx queue used by the driver for the frame.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Reported-by: NBjörn Smedman <bjorn.smedman@venatech.se>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

OProfile showed that ath9k was spending way too much time in
ath9k_hw_set_interrupts. Since most of the interrupt mask changes only
need to globally enable/disable interrupts, it makes sense to split
this part into separate functions, replacing all calls to
ath9k_hw_set_interrupts(ah, 0) with ath9k_hw_disable_interrupts(ah).

ath9k_hw_set_interrupts(ah, ah->imask) only gets changed to
ath9k_hw_enable_interrupts(ah), whenever ah->imask was not changed
since the point where interrupts were disabled.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since aggregation is usually triggered by tx completion, a hardware
reset (because of beacon stuck, tx hang or baseband hang) can
significantly delay the transmission of the next AMPDU (until the next
tx completion event).
Fix this by rescheduling aggregation after such a reset.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This doesn't fix any problem that I'm aware of, but should
make it harder to add use-after-free type bugs in the
future.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The bf_dmacontext seems to be totally useless and duplicated
by bf_buf_addr.  Remove it entirely, use bf_buf_addr in its
place.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When beacons get stuck in AP mode, the most likely cause is interference.
Such interference can often go on for a while, and too many consecutive
beacon misses can lead to connected clients getting dropped.

Since connected clients might not be subjected to the same interference
if that happens to be very local, the AP should try to deal with it as
good as it can. One way to do this is to trigger an NF calibration with
automatic baseband update right after the beacon miss. In my tests with
very strong interference, this allowed the AP to continue transmitting
beacons after only 2-3 misses, which allows a normal client to stay
connected.

With some of the newer - really sensitive - chips, the maximum noise
floor limit is very low, which can be problematic during very strong
interference. To avoid an endless loop of stuck beacons -> nfcal ->
periodic calibration -> stuck beacons, the beacon miss event also sets
a flag, which allows the calibration code to bypass the chip specific
maximum NF value. This flag is automatically cleared, as soon as the
first NF median goes back below the limits for all chains.

In my tests, this allowed an ath9k AP to survive very strong interference
(measured NF: -68, or sometimes even higher) without losing connectivity
to its clients. Even under these conditions, I was able to transmit
several mbits/s through the interface.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Stuck beacons are a useful indicator for debugging various PHY
issues such as calibration. Putting them on the same debug level
as the other beacon stuff makes it hard to spot them in huge amounts
of spam.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

With VEOL, Beacon transmission in ad-hoc does not currently work.
I believe for larger ad-hoc networks, VEOL is too unreliable, as
it can get beacon transmissions stuck during synchronization.
Use SWBA based beacon trasmission similar to AP mode instead.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Acked-by: NBenoit Papillault <benoit.papillault@free.fr>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This fixes IBSS beacon transmissions without VEOL enabled
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add ah variable in the functions that didn't have it and used sc->imask.
Replace sc->sc_ah with ah in those functions.
Signed-off-by: NPavel Roskin <proski@gnu.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In AP mode, ath_beacon_config_ap only restarts the timer if a TSF
restart is requested. Apparently this was added, because this function
unconditionally sets the flag for TSF reset.

The problem with this is, that ath9k_hw_reset() clobbers the timer
registers (specified in the initvals), thus effectively disabling the
SWBA interrupt whenever a card reset without TSF reset is issued
(happens in a few places in the code).

This patch fixes ath_beacon_config_ap to only issue the TSF reset flag
when necessary, but reinitialize the timer unconditionally. Tests show,
that this is enough to keep the SWBA interrupt going after a call to
ath_reset()
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Instead of hardcoding the lowest rate for Beacon frames, use the rate
index specified in the mac80211 TX info in AP mode.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

beacons configuration SHOULD be done only if the STA is associated.
Signed-off-by: NSenthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Previously ath9k left the initialization of slot timing and ACK/CTS
timeout to the mode specific initvals. This does not handle short vs
long slot in 2.4 GHz and uses a rather strange value for the 2.4 GHz
ACK timeout (64 usec).
This patch uses the proper ath9k_hw functions for setting slot time and
timeouts and also implements the switch between short and long slot
time in 2.4 GHz
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Update the beacon queue parameters with best effort queue parameters for
IBSS mode. This reduces the number of beacons generated by ath9k and
ensures a fair beacon distribution when there are multiple IBSS stations.
Also CWmin is quadrupled to achieve the expected percentage of
distribution.
Signed-off-by: NVivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch changes ath9k to pass proper MCS indexes and flags
between the RC and the rest of the driver code.
sc->cur_rate_table remains, as it's used by the RC code internally,
but the rest of the driver code no longer uses it, so a potential
new RC for ath9k would not have to update it.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

And move it to hw code on mac.c where it belongs.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ath9k uses this for now, ath9k_htc is expected to re-use this
as well. We lave ath5k as is, but it certainly can also be
converted later.

The ath9k module parameter and debugfs entry is kept.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the TSF is reset power save state is disabled and
then restored. The helpers to disable power save and restore
it use a lock provided by the driver core. Move the callers
of the helpers outside of the hw code.

We reset the TSF when mac80211 tells us and on the beacon.c
helper ath9k_hw_beaconinit() when it is made explicitly required.
Add a helper on beacon.c which will deal with ps awake/restore
if we need to reset the TSF upon ath9k_hw_beaconinit().
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>