This fix ensure the timers to be set at beacon interval boundaries.
Without this change timers can be set improperly resulting in the absence of beacons.
Signed-off-by: NFabrice Deyber <fabricedeyber@agilemesh.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Earlier beacon_interval is used to hold interval value and
some flags (ATH9K_BEACON_ENA &ATH9K_BEACON_PERIOD). So to
extract interval ATH9K_BEACON_PERIOD is used. Those flags
were completely removed. So masking beacon_interval is
not required.
Signed-off-by: NRajkumar Manoharan <rmanoharan@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>

rounding up the delta between last-beacon-tsf and tsf to intval is wrong
and can lead to misconfigured timers which breaks beacon transmission.
Fix this by adding intval and subtracting the offset of the tsf within the
current slot.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The Times They Are a-Changin'.
Signed-off-by: NSujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In ad-hoc mode, beacon timers are configured differently compared to AP
mode, and (depending on the scenario) can vary enough to make the beacon
tasklet not detect slot 0 based on the TSF.
Since staggered beacons are not (and cannot be) used in ad-hoc mode, it
makes more sense to just hardcode slot 0 here, avoiding unnecessary
TSF reads and calculations.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Reported-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The assumsion is that while processing ath9k tasklet,
interrupts were already disabled and it will be enabled
at the completion of ath9k tasklet. But whenever TSFOOR is raised,
the driver configures the beacon timers after having received a
beacon frame from the AP which inturn enables the interrupts.

Cc: stable@kernel.org
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Requesting beacon sync up to configure beacon timers properly
in hw, has be done after doing beacon config with default values.
Setting the flags in beacon config is causing the device to not
enter into network sleep on idle state.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

While leaving the oper channel, beacon generation is stopped
by mac80211 and beacon slots are marked as inactive.
During the scan, ath9k configures beacon timers
based on IEEE80211_CONF_OFFCHANNEL which inturn generates
beacon alert even though bslot is inactive.

ath9k fails to disable beacon alert while moving to offchannel
if none of the beacon slot is active. This is causing beacon
transmission on foreign channel. This patch enables swba
based on active bslots.

This issue was reported with two vifs (AP+STA) and triggered
scan in STA vif in unassociated state.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Request a re-configuration of Beacon related timers
on the receipt of the first Beacon frame has to be set only
for station mode. Setting beacon sync for IBSS is causing
wrong beacon slot selection on beacon generation.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The commit "ath9k: configure beacons based on hw opmode" introduced
a regression which leads to kernel panic. Failed to stop ani timer
during the driver unload while any of the beaconing vif is running.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Current ath9k code does not handle beacon timers on opmode
specific. One such example is that a STA beacon config overwrites
already configured AP vif's beacon timers during scan.

On multi station vif case, configure beacon timers beased
on primary vif selected. This also helps while moving back
to single STA vif from multi STA vifs, where the power save
is enabled and hw has to be reconfigured with proper
beacon and bssid/aid. Otherwise connection poll will be triggered
so frequently due to beacon loss.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Remove unused bssid from ath_vif and set av_bslot on beacon
alloc/return.
Signed-off-by: NRajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since the beacon timers are global, the individual vif type should not
be used to determine the beacon timer configuration mode, use the
global opmode instead.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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>