Clearing IEEE80211_TX_CTL_PS_RESPONSE in a frame
that is not in the current context doesn't seem right.
Instead make sure that we don't add such frames
to the UAPSD queue by using a local variable.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There is no reason why frames marked with
IEEE80211_TX_CTL_TX_OFFCHAN have to be sent using
the UAPSD queue. Since mac80211 makes sure that
RoC is done before pushing an offchannel frame
to the driver, we can use the normal TX queues
for transmission.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since we use IEEE80211_HW_QUEUE_CONTROL now, the
CAB/Offchannel queues are registered as the last
two queues. There is no need to check and reassign
the queues in the TX start()/done() routines.

CAB frames will not reach the tx() callback since
we set IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING and
pull the buffered frames during beacon transmission.
We also don't have a special HW queue for handling
off-channel frames.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add sampling methods for ACK RX timestamp in ath_rx_tasklet() and for TX frame
timestamp in ath_tx_complete_aggr() and in ath_tx_process_buffer(). These
samples will be used in dynack processing for ACK timeout estimation
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Check if channel context usage is enabled before
calling ath_chanctx_event() from various parts of the
driver. Also, make sure that ath_chanctx_event() is
compiled only when CONFIG_ATH9K_CHANNEL_CONTEXT is
enabled.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If an aggregation session fails, frames still end up in the driver queue
with IEEE80211_TX_CTL_AMPDU set.
This causes tx for the affected station/tid to stall, since
ath_tx_get_tid_subframe returning packets to send.

Fix this by clearing IEEE80211_TX_CTL_AMPDU as long as no aggregation
session is running.

Cc: stable@vger.kernel.org
Reported-by: NAntonio Quartulli <antonio@open-mesh.com>
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Packets originally buffered for the regular hardware tx queues can end
up being transmitted through the U-APSD queue (via PS-Poll or U-APSD).
When packets are dropped due to retransmit failures, the pending frames
counter is not always updated properly.
Fix this by keeping track of the queue that a frame was accounted for in
the ath_frame_info struct, and using that on completion to decide
whether the counter should be updated.
This fixes some spurious transmit queue hangs.

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

Use seperate tx queue for each AC in each channel context and expose
these information to mac80211 to avoid stopping one channel context
leads to stopping the entire traffic for that AC even on other contexts.
Signed-off-by: NRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add a basic state machine for switch channel context
for beacon transmission.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add remain on channel support in order to enable multi-channel
concurrency.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Force queueing of all frames that belong to a virtual interface on
a different channel context, to ensure that they are sent on the
correct channel.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The channel context worker is used to switch to next requested
channel context.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add support to maintain per-channel ACs list.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There are some corner cases where the driver could get stuck with a full
tid queue that is paused, leading to a software tx queue hang.

Since the tx queueing rework, pausing per-tid queues on aggregation
session setup is no longer necessary. The driver will assign sequence
numbers to buffered frames when a new session is established, in order
to get the correct starting sequence number.

mac80211 prevents new frames from entering the queue during setup.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

we will need it for ath9k_htc, may be other drivers too
Signed-off-by: NOleksij Rempel <linux@rempel-privat.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

qi->tqi_readyTime is written directly to registers that expect
microseconds as unit instead of TU.
When setting the CABQ ready time, cur_conf->beacon_interval is in TU, so
convert it to microseconds before passing it to ath9k_hw.

This should hopefully fix some Tx DMA issues with buffered multicast
frames in AP mode.

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

Since commit 558ff225 (ath9k: fix
ps-poll responses under a-mpdu sessions) non-data frames would have
gotten a sequence number from a TIDs sequence counter instead of
using the global sequence counter.

This can lead to instable connections.

To fix this only select the correct TID if we are processing a
data frame. Furthermore, prevent non-data frames to get a sequence
number from a TID sequence counter by adding a check to
ath_tx_setup_buffer.

Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Acked-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

According to 802.11n-2012 standard in paragraph PPDU Fromat(20.3.2) HT-mixed
format  Hearder PPDU contains : L_STF, L_LTF, L_SIG, HT_SIG, HT_STF, HT_LTF
they are symbols in the preamble, there are in time unit(us) that's for why
it can't be computed in bytes
Signed-off-by: NSylvain ROGER RIEUNIER <sylvain.roger.rieunier@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

and rename it to ath9k_cmn_init_channels_rates.
sbands are move to ath_common as well.
Signed-off-by: NOleksij Rempel <linux@rempel-privat.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When passing tx frames to the U-APSD queue for powersave poll responses,
the ath_atx_tid pointer needs to be passed to ath_tx_setup_buffer for
proper sequence number accounting.

This fixes high latency and connection stability issues with ath9k
running as AP and a few kinds of mobile phones as client, when PS-Poll
is heavily used

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

We check tid->sched without a lock taken on ath_tx_aggr_sleep(). That
is race condition which can result of doing list_del(&tid->list) twice
(second time with poisoned list node) and cause crash like shown below:

[424271.637220] BUG: unable to handle kernel paging request at 00100104
[424271.637328] IP: [<f90fc072>] ath_tx_aggr_sleep+0x62/0xe0 [ath9k]
...
[424271.639953] Call Trace:
[424271.639998]  [<f90f6900>] ? ath9k_get_survey+0x110/0x110 [ath9k]
[424271.640083]  [<f90f6942>] ath9k_sta_notify+0x42/0x50 [ath9k]
[424271.640177]  [<f809cfef>] sta_ps_start+0x8f/0x1c0 [mac80211]
[424271.640258]  [<c10f730e>] ? free_compound_page+0x2e/0x40
[424271.640346]  [<f809e915>] ieee80211_rx_handlers+0x9d5/0x2340 [mac80211]
[424271.640437]  [<c112f048>] ? kmem_cache_free+0x1d8/0x1f0
[424271.640510]  [<c1345a84>] ? kfree_skbmem+0x34/0x90
[424271.640578]  [<c10fc23c>] ? put_page+0x2c/0x40
[424271.640640]  [<c1345a84>] ? kfree_skbmem+0x34/0x90
[424271.640706]  [<c1345a84>] ? kfree_skbmem+0x34/0x90
[424271.640787]  [<f809dde3>] ? ieee80211_rx_handlers_result+0x73/0x1d0 [mac80211]
[424271.640897]  [<f80a07a0>] ieee80211_prepare_and_rx_handle+0x520/0xad0 [mac80211]
[424271.641009]  [<f809e22d>] ? ieee80211_rx_handlers+0x2ed/0x2340 [mac80211]
[424271.641104]  [<c13846ce>] ? ip_output+0x7e/0xd0
[424271.641182]  [<f80a1057>] ieee80211_rx+0x307/0x7c0 [mac80211]
[424271.641266]  [<f90fa6ee>] ath_rx_tasklet+0x88e/0xf70 [ath9k]
[424271.641358]  [<f80a0f2c>] ? ieee80211_rx+0x1dc/0x7c0 [mac80211]
[424271.641445]  [<f90f82db>] ath9k_tasklet+0xcb/0x130 [ath9k]

Bug report:
https://bugzilla.kernel.org/show_bug.cgi?id=70551Reported-and-tested-by: NMax Sydorenko <maxim.stargazer@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Soon mac80211 will support multi-interface CSA so
using sc->csa_vif is not an option.

Instead just depend on vif->csa_active. Calling
ieee80211_csa_finish() multiple number of times
should not be an issue.
Signed-off-by: NMichal Kazior <michal.kazior@tieto.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This would be useful when debugging RX performance issues.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The maximum A-MPDU size is calculated in ath_tx_aggr_start(),
so there is no need to do it in node_attach() too. Also, make
sure that the correct size is calculated as described in
8.4.2.58.3.
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

mac80211 guarantees that skb->priority is set to the TID, so use it
instead of trying to parse the QoS header manually.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When not aggregating packets, fi->framelen should be passed in as length
to calculate the duration. Before the tx path rework, ath_tx_fill_desc
was called for either one aggregate, or one single frame, with the
length of the packet or the aggregate as a parameter.
After the rework, ath_tx_sched_aggr can pass a burst of single frames to
ath_tx_fill_desc and sets len=0.
Fix broken duration calculation by overriding the length in ath_tx_fill_desc
before passing it to ath_buf_set_rate.

Cc: stable@vger.kernel.org
Reported-by: NSimon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If the software has processed all packets, checking the hardware queue
is unnecessary.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Use CONFIG_ATH9K_TX99 to properly enclose the tx99 code
and make sure that it is not compiled as part of the driver
when it is not selected. Move the tx99 code to a new file tx99.c
and also add ATH9K_DEBUGFS as a dependency in Kconfig.

This reduces the module size on platforms like OpenWrt where
ATH9K_DEBUGFS is selected, but TX99 might be disabled.

Cc: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

TX99 support enables Specific Absorption Rate (SAR) testing.
SAR is the unit of measurement for the amount of radio frequency(RF)
absorbed by the body when using a wireless device. The RF
exposure limits used are expressed in the terms of SAR, which is a
measure of the electric and magnetic field strength and power density
for transmitters operating at frequencies from 300 kHz to 100 GHz.

Regulatory bodies around the world require that wireless device
be evaluated to meet the RF exposure limits set forth in the
governmental SAR regulations.

In the examples below, for more bit rate options see the iw TX bitrate
setting documentation:

http://wireless.kernel.org/en/users/Documentation/iw#Modifying_transmit_bitrates

Example usage:

iw phy phy0 interface add moni0 type monitor
ip link set dev moni0 up

iw dev moni0 set channel 36 HT40+
iw set bitrates mcs-5 4

echo 10 > /sys/kernel/debug/ieee80211/phy0/ath9k/tx99_power
echo 1  > /sys/kernel/debug/ieee80211/phy0/ath9k/tx99
Signed-off-by: NRajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: NLuis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ieee80211_get_rts_cts_rate() can return NULL, so don't rely
on its members when it does return NULL.
Signed-off-by: NRajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: NLuis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

It is not exposed as a configuration option anyway
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Use wrappers where available. Simplifies code and helps with further
improvements to the channel data structure
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When a packet is passed from mac80211 to the driver with the
IEEE80211_TX_CTL_PS_RESPONSE flag set, it bypasses the normal driver
internal queueing and goes directly to the UAPSD queue.

When that happens, packets that are part of a BlockAck session still
need to be tracked as such inside the driver, otherwise it will create
discrepancies in the receiver BA reorder window, causing traffic stalls.
This only happens in AP mode with powersave-enabled clients.

This patch fixes the regression introduced in the commit
"ath9k: use software queues for un-aggregated data packets"
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NSujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Prevents race conditions when un-aggregated frames are pending in the
driver.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When .release_buffered_frames was implemented, only A-MPDU packets were
buffered internally. Now that this has changed, the BUF_AMPDU flag needs
to be checked before calling ath_tx_addto_baw
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This might trip up tx completion processing, although the condition that
triggers this should not (yet) occur in practice.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fixes a regression from commit
"ath9k: shrink a few data structures by reordering fields"

When cloning a buffer, the stale flag (part of bf_state now) needs to be
reset after copying the state to prevent tx processing hangs.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

CSA is only enabled for one interface, but the same limitation applies
for mac80211 too. It checks whether the beacon has been sent (different
approaches for non-EDMA-enabled and EDMA-enabled devices), and completes
the channel switch after that.
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NMathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>