wifi: ath9k: remove redundant assignment to variable ret

The variable ret is being assigned a value but it isn't being
read afterwards. The assignment is redundant and so ret can be
removed.

Cleans up clang scan build warning:
warning: Although the value stored to 'ret' is used in the
enclosing expression, the value is never actually read from
'ret' [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://msgid.link/20240116155452.2315351-1-colin.i.king@gmail.com

wifi: mac80211: rename ieee80211_tx_status() to ieee80211_tx_status_skb()

make htmldocs warns:

Documentation/driver-api/80211/mac80211:109: ./include/net/mac80211.h:5170: WARNING: Duplicate C declaration, also defined at mac80211:1117.
Declaration is '.. c:function:: void ieee80211_tx_status (struct ieee80211_hw *hw, struct sk_buff *skb)'.

This is because there's a function named ieee80211_tx_status() and a struct named
ieee80211_tx_status. This has been discussed previously but no solution found:

https://lore.kernel.org/all/20220521114629.6ee9fc06@coco.lan/

There's also a bug open for three years with no solution in sight:

https://github.com/sphinx-doc/sphinx/pull/8313

So I guess we have no other solution than to a workaround this in the code,
for example to rename the function to ieee80211_tx_status_skb() to avoid the
name conflict. I got the idea for the name from ieee80211_tx_status_noskb() in
which the skb is not provided as an argument, instead with
ieee80211_tx_status_skb() the skb is provided.

Compile tested only.

Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20231012114229.2931808-2-kvalo@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: ath9k: fix fortify warnings

When compiling with gcc 13.1 and CONFIG_FORTIFY_SOURCE=y,
I've noticed the following:

In function ‘fortify_memcpy_chk’,
inlined from ‘ath_tx_complete_aggr’ at drivers/net/wireless/ath/ath9k/xmit.c:556:4,
inlined from ‘ath_tx_process_buffer’ at drivers/net/wireless/ath/ath9k/xmit.c:773:3:
./include/linux/fortify-string.h:529:25: warning: call to ‘__read_overflow2_field’
declared with attribute warning: detected read beyond size of field (2nd parameter);
maybe use struct_group()? [-Wattribute-warning]
529 | __read_overflow2_field(q_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In function ‘fortify_memcpy_chk’,
inlined from ‘ath_tx_count_frames’ at drivers/net/wireless/ath/ath9k/xmit.c:473:3,
inlined from ‘ath_tx_complete_aggr’ at drivers/net/wireless/ath/ath9k/xmit.c:572:2,
inlined from ‘ath_tx_process_buffer’ at drivers/net/wireless/ath/ath9k/xmit.c:773:3:
./include/linux/fortify-string.h:529:25: warning: call to ‘__read_overflow2_field’
declared with attribute warning: detected read beyond size of field (2nd parameter);
maybe use struct_group()? [-Wattribute-warning]
529 | __read_overflow2_field(q_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In both cases, the compiler complains on:

memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);

which is the legal way to copy both 'ba_low' and following 'ba_high'
members of 'struct ath_tx_status' at once (that is, issue one 8-byte
'memcpy()' for two 4-byte fields). Since the fortification logic seems
interprets this trick as an attempt to overread 4-byte 'ba_low', silence
relevant warnings by using the convenient 'struct_group()' quirk.

Suggested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230620080855.396851-2-dmantipov@yandex.ru

wifi: ath9k: avoid using uninitialized array

In 'ath_tx_count_frames()', 'ba' array may be used uninitialized, so
add 'memset()' call similar to one used in 'ath_tx_complete_aggr()'.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230620080855.396851-1-dmantipov@yandex.ru

wifi: ath9k: fix per-packet TX-power cap for TPC

Fix incorrect usage of plain rate_idx as index into the max (power) per
rate lookup table.

For transmit power control (TPC), the ath9k driver maintains internal
tables (in struct ath_hw) to store the max allowed power level per rate.
They are used to limit a given TX-power according to regulatory and user
limits in the TX-path per packet. The tables are filled in a predefined
order, starting with values for CCK + OFDM rates and followed by the
values for MCS rates. Thus, the maximum power levels for MCS do not
start at index 0 in the table but are shifted by a fixed value.

The TX-power limiting in ath_get_rate_txpower currently does not apply
this shift, thus retrieves the incorrect maximum power level for a given
rate. In particular for MCS rates, the maximum power levels for CCK/OFDM
rates were used, e.g. maximum power for OFDM 0 was used for MCS 0. If
STBC is used, the power is mostly limited to 0 because the STBC table
is zeroed for legacy CCK/OFDM rates. Encountered this during testing of
our work-in-progress TPC per packet for ath9k.
This only has an effect when TPC is enabled in ath9k (tpc_enabled in
struct ath_hw) which defaults to false. In this case it has a
significant impact on the used TX-power, throughput + RSSI. Otherwise
the affected code is just skipped and TX-power is limited with the
hardware registers only. This patch fixes this table lookup.

Tested on OpenWrt (kernel 5.15.98, but backported ath9k driver) with
small desk setup using ath9k chips AR9280 and AR9580. Cap of TX-power is
working properly for all rates now, throughput and RSSI as expected,
equal to as if TPC was disabled.
Compile-tested with latest 6.3 kernel + allyesconfig.

Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230330132159.758088-1-jelonek.jonas@gmail.com

wifi: ath9k: remove most hidden macro dependencies on ah

Adds an explicit _ah parameter to most macros that previously had a
hidden dependency on ah. This makes the code more compliant with the
style guide.

This change does not appear to affect the final binary.

Signed-off-by: Wenli Looi <wlooi@ucalgary.ca>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/c8369317-cf84-f0e3-fe8-9b6e22e43a6a@ucalgary.ca

wifi: ath9k: remove variable sent

Variable sent is just being incremented and it's never used
anywhere else. The variable and the increment are redundant so
remove it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20221024153954.2168503-1-colin.i.king@gmail.com

wifi: mac80211: make smps_mode per-link

The SMPS power save mode needs to be per-link rather than being shared
for all links. As such, move it into struct ieee80211_link_sta.

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: fix ath_get_rate_txpower() to respect the rate list end tag

Stop reading (and copying) from ieee80211_tx_rate to ath_tx_info.rates
after list end tag (count == 0, idx < 0), prevents copying of garbage
to card registers.

Note: no need to write to the remaining ath_tx_info.rates entries
as the complete ath_tx_info struct is already initialized to zero from
both call sites.

Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20220402153014.31332-1-ps.report@gmx.net

mac80211: prepare sta handling for MLO support

Currently in mac80211 each STA object is represented
using sta_info datastructure with the associated
STA specific information and drivers access ieee80211_sta
part of it.

With MLO (Multi Link Operation) support being added
in 802.11be standard, though the association is logically
with a single Multi Link capable STA, at the physical level
communication can happen via different advertised
links (uniquely identified by Channel, operating class,
BSSID) and hence the need to handle multiple link
STA parameters within a composite sta_info object
called the MLD STA. The different link STA part of
MLD STA are identified using the link address which can
be same or different as the MLD STA address and unique
link id based on the link vif.

To support extension of such a model, the sta_info
datastructure is modified to hold multiple link STA
objects with link specific params currently within
sta_info moved to this new structure. Similarly this is
done for ieee80211_sta as well which will be accessed
within mac80211 as well as by drivers, hence trivial
driver changes are expected to support this.

For current non MLO supported drivers, only one link STA
is present and link information is accessed via 'deflink'
member.

For MLO drivers, we still need to define the APIs etc. to
get the correct link ID and access the correct part of
the station info.

Currently in mac80211, all link STA info are accessed directly
via deflink. These will be updated to access via link pointers
indexed by link id with MLO support patches, with link id
being 0 for non MLO supported cases.

Except for couple of macro related changes, below spatch takes
care of updating mac80211 and driver code to access to the
link STA info via deflink.

@ieee80211_sta@
struct ieee80211_sta *s;
struct sta_info *si;
identifier var = {supp_rates, ht_cap, vht_cap, he_cap, he_6ghz_capa, eht_cap, rx_nss, bandwidth, txpwr};
@@

(
s->
- var
+ deflink.var
|
si->sta.
- var
+ deflink.var
)

@sta_info@
struct sta_info *si;
identifier var = {gtk, pcpu_rx_stats, rx_stats, rx_stats_avg, status_stats, tx_stats, cur_max_bandwidth};
@@

(
si->
- var
+ deflink.var
)

Signed-off-by: Sriram R <quic_srirrama@quicinc.com>
Link: https://lore.kernel.org/r/1649086883-13246-1-git-send-email-quic_srirrama@quicinc.com
[remove MLO-drivers notes from commit message, not clear yet; run spatch]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: Fix usage of driver-private space in tx_info

The ieee80211_tx_info_clear_status() helper also clears the rate counts and
the driver-private part of struct ieee80211_tx_info, so using it breaks
quite a few other things. So back out of using it, and instead define a
ath-internal helper that only clears the area between the
status_driver_data and the rates info. Combined with moving the
ath_frame_info struct to status_driver_data, this avoids clearing anything
we shouldn't be, and so we can keep the existing code for handling the rate
information.

While fixing this I also noticed that the setting of
tx_info->status.rates[tx_rateindex].count on hardware underrun errors was
always immediately overridden by the normal setting of the same fields, so
rearrange the code so that the underrun detection actually takes effect.

The new helper could be generalised to a 'memset_between()' helper, but
leave it as a driver-internal helper for now since this needs to go to
stable.

Cc: stable@vger.kernel.org
Reported-by: Peter Seiderer <ps.report@gmx.net>
Fixes: 037250f0a45c ("ath9k: Properly clear TX status area before reporting to mac80211")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Peter Seiderer <ps.report@gmx.net>
Tested-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220404204800.2681133-1-toke@toke.dk

ath9k: Properly clear TX status area before reporting to mac80211

The ath9k driver was not properly clearing the status area in the
ieee80211_tx_info struct before reporting TX status to mac80211. Instead,
it was manually filling in fields, which meant that fields introduced later
were left as-is.

Conveniently, mac80211 actually provides a helper to zero out the status
area, so use that to make sure we zero everything.

The last commit touching the driver function writing the status information
seems to have actually been fixing an issue that was also caused by the
area being uninitialised; but it only added clearing of a single field
instead of the whole struct. That is now redundant, though, so revert that
commit and use it as a convenient Fixes tag.

Fixes: cc591d77aba1 ("ath9k: Make sure to zero status.tx_time before reporting TX status")
Reported-by: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220330164409.16645-1-toke@toke.dk

ath9k: switch to rate table based lookup

This patch changes mac80211 rate control for the ath9k driver. The rate lookup
per packet is changed from legacy usage of ieee80211_get_tx_rates() to the new
rate table based lookup in struct ieee80211_sta->rates.

The most recent rate control API, introduced with commit 0d528d85c519
("mac80211: improve the rate control API"), allows drivers to directly get
rates from ieee80211_sta->rates. This is not used by every driver yet, the
translation/merge is currently performed in ieee80211_get_tx_rates. This patch
changes the behaviour and avoids the call to ieee80211_get_tx_rates and
subsequent calls. ath9k now directly reads rates from sta->rates into its rate
table. Cause ath9k does not expect rate selection in SKB->CB, the table merge
does not consider rate array in SKB->CB except for the first entry (used for
probing).

Tested with a 8devices Rambutan with QCA9558 SoC by performing two runs, one
without the patch and one with. Generated traffic between AP and multiple STAs
in each run, measured throughput and captured rc_stats. Comparison of both
runs resulted in same rate selection and no performance loss or other negative
effects.

Co-developed-by: Thomas Huehn <thomas.huehn@hs-nordhausen.de>
Signed-off-by: Thomas Huehn <thomas.huehn@hs-nordhausen.de>
Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20211128090753.958-1-jelonek.jonas@gmail.com

Revert "ath9k: fix ath_tx_process_buffer() potential null ptr dereference"

This reverts commit a56c14bb21b296fb6d395164ab62ef2e419e5069.

ath_tx_process_buffer() doesn't dereference or check sta and passes it
to ath_tx_complete_aggr() and ath_tx_complete_buf().

ath_tx_complete_aggr() checks the pointer before use. No problem here.

ath_tx_complete_buf() doesn't check or dereference sta and passes it on
to ath_tx_complete(). ath_tx_complete() doesn't check or dereference sta,
but assigns it to tx_info->status.status_driver_data[0]

ath_tx_complete_buf() is called from ath_tx_complete_aggr() passing
null ieee80211_sta pointer.

There is a potential for dereference later on, if and when the
tx_info->status.status_driver_data[0]is referenced. In addition, the
rcu read lock might be released before referencing the contents.

ath_tx_complete_buf() should be fixed to check sta perhaps? Worth
looking into.

Reverting this patch because it doesn't solve the problem and introduces
memory leak by skipping buffer completion if the pointer (sta) is NULL.

Fixes: a56c14bb21b2 ("ath9k: fix ath_tx_process_buffer() potential null ptr dereference")
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210217211801.22540-1-skhan@linuxfoundation.org

ath9k: fix ath_tx_process_buffer() potential null ptr dereference

ath_tx_process_buffer() references ieee80211_find_sta_by_ifaddr()
return pointer (sta) outside null check. Fix it by moving the code
block under the null check.

This problem was found while reviewing code to debug RCU warn from
ath10k_wmi_tlv_parse_peer_stats_info() and a subsequent manual audit
of other callers of ieee80211_find_sta_by_ifaddr() that don't hold
RCU read lock.

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/43ed9abb9e8d7112f3cc168c2f8c489e253635ba.1613090339.git.skhan@linuxfoundation.org

ath9k: fix transmitting to stations in dynamic SMPS mode

When transmitting to a receiver in dynamic SMPS mode, all transmissions that
use multiple spatial streams need to be sent using CTS-to-self or RTS/CTS to
give the receiver's extra chains some time to wake up.
This fixes the tx rate getting stuck at <= MCS7 for some clients, especially
Intel ones, which make aggressive use of SMPS.

Cc: stable@vger.kernel.org
Reported-by: Martin Kennedy <hurricos@gmail.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210214184911.96702-1-nbd@nbd.name

mac80211: Fix setting txpower to zero

With multiple VIFS ath10k, and probably others, tries to find the
minimum txpower for all vifs and uses that when setting txpower in
the firmware.

If a second vif is added and starts to scan, it's txpower is not
initialized yet and it set to zero.

ath10k had a patch to ignore zero values, but then it is impossible
to actually set txpower to zero.

So, instead initialize the txpower to INT_MIN in mac80211, and let
drivers know that means the power has not been set and so should
be ignored.

This should fix regression in:

commit 88407beb1b1462f706a1950a355fd086e1c450b6
Author: Ryan Hsu <ryanhsu@qca.qualcomm.com>
Date: Tue Dec 13 14:55:19 2016 -0800

ath10k: fix incorrect txpower set by P2P_DEVICE interface

Tested on ath10k 9984 with ath10k-ct firmware.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Link: https://lore.kernel.org/r/20191217183057.24586-1-greearb@candelatech.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: Remove some set but not used variables

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/wireless/ath/ath9k/xmit.c: In function 'ath_tx_count_frames':
drivers/net/wireless/ath/ath9k/xmit.c:413:25: warning: variable 'fi' set but not used [-Wunused-but-set-variable]
drivers/net/wireless/ath/ath9k/xmit.c: In function 'ath_tx_complete_aggr':
drivers/net/wireless/ath/ath9k/xmit.c:449:24: warning: variable 'hdr' set but not used [-Wunused-but-set-variable]
drivers/net/wireless/ath/ath9k/xmit.c: In function 'ath_tx_start':
drivers/net/wireless/ath/ath9k/xmit.c:2274:18: warning: variable 'avp' set but not used [-Wunused-but-set-variable]
drivers/net/wireless/ath/ath9k/xmit.c:2269:24: warning: variable 'hdr' set but not used [-Wunused-but-set-variable]

These variables are not used any more
and can be removed.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: Don't trust TX status TID number when reporting airtime

As already noted a comment in ath_tx_complete_aggr(), the hardware will
occasionally send a TX status with the wrong tid number. If we trust the
value, airtime usage will be reported to the wrong AC, which can cause the
deficit on that AC to become very low, blocking subsequent attempts to
transmit.

To fix this, account airtime usage to the TID number from the original skb,
instead of the one in the hardware TX status report.

Reported-by: Miguel Catalan Cid <miguel.catalan@i2cat.net>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

mac80211: make ieee80211_schedule_txq schedule empty TXQs

Currently there is no way for the driver to signal to mac80211 that it should
schedule a TXQ even if there are no packets on the mac80211 part of that queue.
This is problematic if the driver has an internal retry queue to deal with
software A-MPDU retry.

This patch changes the behavior of ieee80211_schedule_txq to always schedule
the queue, as its only user (ath9k) seems to expect such behavior already:
it calls this function on tx status and on powersave wakeup whenever its
internal retry queue is not empty.

Also add an extra argument to ieee80211_return_txq to get the same behavior.

This fixes an issue on ath9k where tx queues with packets to retry (and no
new packets in mac80211) would not get serviced.

Fixes: 89cea7493a346 ("ath9k: Switch to mac80211 TXQ scheduling and airtime APIs")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: Make sure to zero status.tx_time before reporting TX status

Since ath9k reports airtime usage directly using the
ieee80211_report_airtime() callback, it shouldn't also report it using the
tx_time in status. Make sure the field is zeroed before TX status is
reported to avoid spurious airtime being accounted by bits being left over
from earlier uses of the cb.

Fixes: 89cea7493a34 ("ath9k: Switch to mac80211 TXQ scheduling and airtime APIs")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: Switch to mac80211 TXQ scheduling and airtime APIs

This moves the ath9k driver to use the mac80211 TXQ scheduling and
airtime accounting APIs, removing the corresponding state tracking
inside the driver.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
[rmanohar@codeaurora.org: fixed checkpatch error and warnings]
Signed-off-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: make ewma estimation faster

In order to make propagation time estimation faster,
use current sample as ewma output value during 'late ack'
tracking

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix RX_STAT_INC() etc macros

A couple of macros that deal with statistics in ath9k rely on the
declaration of the 'sc' variable, which they dereference.

However, when the statistics are disabled, the new instance in
ath_cmn_process_fft() causes a warning for an unused variable:

drivers/net/wireless/ath/ath9k/common-spectral.c: In function 'ath_cmn_process_fft':
drivers/net/wireless/ath/ath9k/common-spectral.c:474:20: error: unused variable 'sc' [-Werror=unused-variable]

It's better if those macros only operate on their arguments instead of
known variable names, and adding a cast to (void) kills off that warning.

Fixes: 03224678c013 ("ath9k: add counters for good and errorneous FFT/spectral frames")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: add back support for using active monitor interfaces for tx99

Various documented examples on how to set up tx99 with ath9k rely
on setting up a regular monitor interface for setting the channel.
My previous patch "ath9k: fix tx99 with monitor mode interface" made
it possible to set it up this way again. However, it was removing support
for using an active monitor interface, which is required for controlling
the bitrate as well, since the bitrate is not passed down with a regular
monitor interface.

This patch partially reverts the previous one, but keeps support for using
a regular monitor interface to keep documented steps working in cases
where the bitrate does not matter

Fixes: d9c52fd17cb48 ("ath9k: fix tx99 with monitor mode interface")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix tx99 with monitor mode interface

Tx99 is typically configured via a monitor mode interface, which does
not get added to the driver as a vif. Since the code currently expects
a configured virtual interface for tx99, enabling tx99 via debugfs fails.
Since the vif is not needed anyway, remove all checks for it.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
[kvalo@codeaurora.org: s/CPTCFG/CONFIG/]
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix more-data flag for buffered multicast packets

The flag needs to be cleared for the last packet in the list, not the
first one. Fixes some issues with multicast packet loss for powersave
clients connected to an ath9k AP.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix block-ack window tracking issues

Ensure that a buffer gets tracked as part of the block-ack window as
soon as it's dequeued from the tid for the first time. Ensure that
double calls to ath_tx_addto_baw (e.g. on retransmission) don't cause
any issues.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: report tx status on EOSP

Fixes missed indications of end of U-APSD service period to mac80211

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: clear potentially stale EOSP status bit in intermediate queues

Prevents spurious ieee80211_sta_eosp calls.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix moredata bit in PS buffered frame release

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

treewide: Align function definition open/close braces

Some functions definitions have either the initial open brace and/or
the closing brace outside of column 1.

Move those braces to column 1.

This allows various function analyzers like gnu complexity to work
properly for these modified functions.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

ath9k: Protect queue draining by rcu_read_lock()

When ath9k was switched over to use the mac80211 intermediate queues,
node cleanup now drains the mac80211 queues. However, this call path is
not protected by rcu_read_lock() as it was previously entirely internal
to the driver which uses its own locking.

This leads to a possible rcu_dereference() without holding
rcu_read_lock(); but only if a station is cleaned up while having
packets queued on the TXQ. Fix this by adding the rcu_read_lock() to the
caller in ath9k.

Fixes: 50f08edf9809 ("ath9k: Switch to using mac80211 intermediate software queues.")
Cc: stable@vger.kernel.org
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

Revert "mac80211: Add TXQ scheduling API"

This reverts commit e937b8da5a591f141fe41aa48a2e898df9888c95.

Turns out that a new driver (mt76) is coming in through
Kalle's tree, and will conflict with this. It also has some
conflicting requirements, so we'll revisit this later.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Add TXQ scheduling API

This adds an API to mac80211 to handle scheduling of TXQs and changes the
interface between driver and mac80211 for TXQ handling as follows:

- The wake_tx_queue callback interface no longer includes the TXQ. Instead,
the driver is expected to retrieve that from ieee80211_next_txq()

- Two new mac80211 functions are added: ieee80211_next_txq() and
ieee80211_schedule_txq(). The former returns the next TXQ that should be
scheduled, and is how the driver gets a queue to pull packets from. The
latter is called internally by mac80211 to start scheduling a queue, and
the driver is supposed to call it to re-schedule the TXQ after it is
finished pulling packets from it (unless the queue emptied).

The ath9k and ath10k drivers are changed to use the new API.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: clean up and fix ath_tx_count_airtime

ath_tx_count_airtime is doing a lot of unnecessary work:

- Redundant station lookup
- Redundant rcu_read_lock/unlock
- Useless memcpy of bf->rates
- Useless NULL check of bf->bf_mpdu
- Redundant lookup of the skb tid

Additionally, it tries to look up the mac80211 queue index from the txq,
which fails if the frame was delivered via the power save queue.

This patch fixes all of these issues by passing down the right set of
pointers instead of doing extra work

Cc: stable@vger.kernel.org
Fixes: 63fefa050477 ("ath9k: Introduce airtime fairness scheduling between stations")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: rename tx_complete_work to hw_check_work

Also include common MAC alive check. This should make the hang checks
more reliable for modes where beacons are not sent and is used as a
starting point for further hang check improvements

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: do not return early to fix rcu unlocking

Starting with commit d94a461d7a7d ("ath9k: use ieee80211_tx_status_noskb
where possible") the driver uses rcu_read_lock() && rcu_read_unlock(), yet on
returning early in ath_tx_edma_tasklet() the unlock is missing leading to stalls
and suspicious RCU usage:

===============================
[ INFO: suspicious RCU usage. ]
4.9.0-rc8 #11 Not tainted
-------------------------------
kernel/rcu/tree.c:705 Illegal idle entry in RCU read-side critical section.!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
1 lock held by swapper/7/0:
#0:
(
rcu_read_lock
){......}
, at:
[<ffffffffa06ed110>] ath_tx_edma_tasklet+0x0/0x450 [ath9k]

stack backtrace:
CPU: 7 PID: 0 Comm: swapper/7 Not tainted 4.9.0-rc8 #11
Hardware name: Acer Aspire V3-571G/VA50_HC_CR, BIOS V2.21 12/16/2013
ffff88025efc3f38 ffffffff8132b1e5 ffff88017ede4540 0000000000000001
ffff88025efc3f68 ffffffff810a25f7 ffff88025efcee60 ffff88017edebdd8
ffff88025eeb5400 0000000000000091 ffff88025efc3f88 ffffffff810c3cd4
Call Trace:
<IRQ>
[<ffffffff8132b1e5>] dump_stack+0x68/0x93
[<ffffffff810a25f7>] lockdep_rcu_suspicious+0xd7/0x110
[<ffffffff810c3cd4>] rcu_eqs_enter_common.constprop.85+0x154/0x200
[<ffffffff810c5a54>] rcu_irq_exit+0x44/0xa0
[<ffffffff81058631>] irq_exit+0x61/0xd0
[<ffffffff81018d25>] do_IRQ+0x65/0x110
[<ffffffff81672189>] common_interrupt+0x89/0x89
<EOI>
[<ffffffff814ffe11>] ? cpuidle_enter_state+0x151/0x200
[<ffffffff814ffee2>] cpuidle_enter+0x12/0x20
[<ffffffff8109a6ae>] call_cpuidle+0x1e/0x40
[<ffffffff8109a8f6>] cpu_startup_entry+0x146/0x220
[<ffffffff810336f8>] start_secondary+0x148/0x170

Signed-off-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Fixes: d94a461d7a7d ("ath9k: use ieee80211_tx_status_noskb where possible")
Cc: <stable@vger.kernel.org> # v4.9
Acked-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: Turn ath_txq_lock/unlock() into static inlines.

These are one-line functions that just call spin_lock/unlock_bh(); turn
them into static inlines to avoid the function call overhead.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: Introduce airtime fairness scheduling between stations

This reworks the ath9k driver to schedule transmissions to connected
stations in a way that enforces airtime fairness between them. It
accomplishes this by measuring the time spent transmitting to or
receiving from a station at TX and RX completion, and accounting this to
a per-station, per-QoS level airtime deficit. Then, an FQ-CoDel based
deficit scheduler is employed at packet dequeue time, to control which
station gets the next transmission opportunity.

Airtime fairness can significantly improve the efficiency of the network
when station rates vary. The following throughput values are from a
simple three-station test scenario, where two stations operate at the
highest HT20 rate, and one station at the lowest, and the scheduler is
employed at the access point:

Before / After
Fast station 1: 19.17 / 25.09 Mbps
Fast station 2: 19.83 / 25.21 Mbps
Slow station: 2.58 / 1.77 Mbps
Total: 41.58 / 52.07 Mbps

The benefit of airtime fairness goes up the more stations are present.
In a 30-station test with one station artificially limited to 1 Mbps,
we have seen aggregate throughput go from 2.14 to 17.76 Mbps.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: consistently use get_eeprom_rev(ah)

The AR5416_VER_MASK macro does the same as get_eeprom_rev, except that
one has to know the actual EEPROM type (and providing a reference to
that in a variable named "eep"). Additionally the eeprom_*.c
implementations used the same shifting logic multiple times to get the
eeprom revision which was also unnecessary duplication of
get_eeprom_rev.

Also use the AR5416_EEP_VER_MINOR_MASK macro where needed and introduce
a similar macro (AR5416_EEP_VER_MAJOR_MASK) for the major version.
Finally drop AR9287_EEP_VER_MINOR_MASK since it simply duplicates the
already defined AR5416_EEP_VER_MINOR_MASK.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: Switch to using mac80211 intermediate software queues.

This switches ath9k over to using the mac80211 intermediate software
queueing mechanism for data packets. It removes the queueing inside the
driver, except for the retry queue, and instead pulls from mac80211 when
a packet is needed. The retry queue is used to store a packet that was
pulled but can't be sent immediately.

The old code path in ath_tx_start that would queue packets has been
removed completely, as has the qlen limit tunables (since there's no
longer a queue in the driver to limit).

The mac80211 intermediate software queues offer significant latency
reductions, and this patch allows ath9k to realise them. The exact gains
from this varies with the test scenario, but in an access point scenario
we have seen latency reductions ranging from 1/3 to as much as an order
of magnitude. We also achieve slightly better aggregation.

Median latency (ping) figures with this patch applied at the access point,
with two high-rate stations and one low-rate station (HT20 5Ghz), running
a Flent rtt_fair_var_up test with one TCP flow and one ping flow going to
each station:

Fast station Slow station
Default pfifo_fast qdisc: 430.4 ms 638.7 ms
fq_codel qdisc on iface: 35.5 ms 211.8 ms
This patch set: 22.4 ms 38.2 ms

Median aggregation sizes over the same test:

Default pfifo_fast qdisc: 9.5 pkts 1.9 pkts
fq_codel qdisc on iface: 11.2 pkts 1.9 pkts
This patch set: 13.9 pkts 1.9 pkts

This patch is based on Tim's original patch set, but reworked quite
thoroughly.

Cc: Tim Shepard <shep@alum.mit.edu>
Cc: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: improve powersave filter handling

For non-aggregated frames, ath9k was leaving handling of powersave
filtered packets to mac80211. This can be too slow if the intermediate
queue is already filled with packets and mac80211 does not immediately
send a new packet via drv_tx().

Improve response time with filtered frames by triggering clearing the
powersave filter internally.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: use ieee80211_tx_status_noskb where possible

It removes the need for undoing the padding changes to skb->data and it
improves performance by eliminating one tx status lookup per MPDU in the
status path. It is also useful for preparing a follow-up fix to better
handle powersave filtering.

A side effect is that these counters, available via debugfs, become now invalid:

* dot11TransmittedFragmentCount
* dot11FrameDuplicateCount,
* dot11ReceivedFragmentCount
* dot11MulticastReceivedFrameCount

Signed-off-by: Felix Fietkau <nbd@nbd.name>
[kvalo@qca.qualcomm.com: add a note about counters, thanks to Zefir Kurtisi]
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

cfg80211: remove enum ieee80211_band

This enum is already perfectly aliased to enum nl80211_band, and
the only reason for it is that we get IEEE80211_NUM_BANDS out of
it. There's no really good reason to not declare the number of
bands in nl80211 though, so do that and remove the cfg80211 one.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: fix inconsistent indenting on return statement

minor change, indenting is one tab out.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: queue null frames in case of MCC

While mac80211 using null frames when connection polling,
we should queue this frames while NOA could be there, and
AP, P2P_GO could be not present.

Without this patch, with no traffic we often saw disconnections
while we try to send nullfunc when AP/GO wasn't present.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: add debug messages to aggr/chanctx funcs

Add/extend debug messages when chanctx used.

Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

ath9k: remove the sched field in struct ath_atx_tid

Use list_empty(&tid->list) instead

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: remove struct ath_atx_ac

struct ath_atx_ac contains a list of active TIDs belonging to one WMM AC.
This patch changes the code to track active station TIDs in the txq directly.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix moredata flag endianness in cabq tx

While compiling ath9k with some extra flags I've
found that:

ath9k/xmit.c +2473 ## 16: warning: restricted __le16 degrades to integer
ath9k/xmit.c +2474 ## 36: warning: invalid assignment: &=
ath9k/xmit.c +2474 ## 36: left side has type restricted __le16
ath9k/xmit.c +2474 ## 36: right side has type int

There's no way for frame ftype/stype to be
mistreated as the offending 'moredata' flag when
considering cab queue.

This could've however theoretically led sometimes
to increased power consumption on connected
stations as they would keep their Rx active
waiting for frames that would never come.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: make DMA stop related messages debug-only

A long time ago, ath9k had issues during reset where the DMA engine
would stay active and could potentially corrupt memory.
To debug those issues, the driver would print warnings whenever they
occur.

Nowadays, these issues are gone and the primary cause of these messages
is if the MAC is stuck during reset or busy processing a long
transmission. This is fairly harmless, yet these messages continue to
worry users.

To reduce the number of bogus bug reports, turn these messages into
debug messages and count their occurence in the "reset" debugfs file.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix per-packet tx power configuration

Do not use ieee80211_vif pointer in ath_get_rate_txpower() since it has been
overwritten by setup_frame_info() and it will result in a corrupted tx power
configuration. Set per-packet tx power in setup_frame_info() according to
current vif tx power.

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: add per-vif TX power capability to TX path

In order to add per-vif TX power capability cap per-packet TX power to vif
configured power if the latter is lower than per-rate TX power and mac80211
per-frame power. Use vif TX power if TPC has been disabled for current the
interface

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: Fix no-ack frame status

Check if the frame has been completed without any
error and use IEEE80211_TX_STAT_NOACK_TRANSMITTED to
indicate successful transmission of no-ack frames.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: add TPC to TX path for AR9002 based chips

Add TPC capability to TX descriptor path for AR9002 based chips. Scale
per-packet TX power according to eeprom power bias, power adjustments for
HT40 mode and open loop CCK rates. Cap per-packet TX power according to
TX power per-rate tables

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: fix typo

Fix typo

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

mac80211: Move IEEE80211_TX_CTL_PS_RESPONSE

Move IEEE80211_TX_CTL_PS_RESPONSE to info->control.flags since
this is used only in the TX path (by ath9k). This frees up
a bit which can be used for other purposes.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: add TPC capability to TX descriptor path

Add TPC capability to TX descriptor path. Cap per-packet TX power according to
TX power per-rate tables. Currently TPC is supported just by AR9003 based chips

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Enable HW queue control only for MCC

Enabling HW queue control for normal (non-mcc) mode
causes problems with queue management, resulting
in traffic stall. Since it is mainly required for
fairness in MCC mode, disable it for the general case.

Bug: https://dev.openwrt.org/ticket/18164

Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix sequence number assignment

Currently, ath9k uses a global counter for all
frames that need to be assigned a sequence number.
QoS-data frames are handled properly since they
have a per-tid counter. But, beacons and other
management frames use the same counter even if
multiple interfaces or contexts are present.

Fix this issue by making the counter per-interface
and using it when mac80211 sets IEEE80211_TX_CTL_ASSIGN_SEQ.

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

ath9k: fix getting tx duration for dynack

On AR9003, tx control and tx status are in separate descriptor rings.
Tx duration is extracted from the tx control descriptor data, which
ar9003_hw_proc_txdesc cannot access.

Fix getting the duration by adding a separate callback for it.

Acked-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Check early for HW reset

chan_lock is not required for checking if
we are in the middle of a HW reset, so do it
early. This also removes the small window
where the lock is dropped and reacquired.

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

ath9k: Fix offchannel queuing

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

ath9k: Use normal queues for offchannel frames

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

ath9k: Fix queue management

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

ath9k: add sampling methods for (tx|rx) timestamp

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: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix channel context events

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

ath9k: fix aggregation session lockup

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: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix pending tx frames accounting

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

ath9k: use separate HW queue for each channel context

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

ath9k: switch channel context for beaconing

Add a basic state machine for switch channel context
for beacon transmission.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Move beacon config to channel context

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

ath9k: Implement remain-on-channal support

Add remain on channel support in order to enable multi-channel
concurrency.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: channel context based transmission

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: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Add channel context worker thread

The channel context worker is used to switch to next requested
channel context.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Move acq to channel context

Add support to maintain per-channel ACs list.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: remove tid->paused flag

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

ath9k: move sc_flags to ath_common

we will need it for ath9k_htc, may be other drivers too

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix ready time of the multicast buffer queue

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

ath9k: Fix sequence number assignment for non-data frames

Since commit 558ff225de80ac95b132d3a115ddadcd64498b4f (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: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix invalid max frame length

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: Sylvain ROGER RIEUNIER <sylvain.roger.rieunier@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: move ath9k_init_channels_rates to common-init

and rename it to ath9k_cmn_init_channels_rates.
sbands are move to ath_common as well.

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix ps-poll responses under a-mpdu sessions

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

ath9k: protect tid->sched check

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=70551

Reported-and-tested-by: Max Sydorenko <maxim.stargazer@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: prepare for multi-interface CSA support

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: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Add a debugfs file "node_recv"

This would be useful when debugging RX performance issues.

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

ath9k: Fix max AMPDU size calculation

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

ath9k: simplify/fix tx packet TID handling

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

ath9k: fix duration calculation for non-aggregated packets

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: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: optimize ath_drain_all_txq

If the software has processed all packets, checking the hardware queue
is unnecessary.

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

ath9k: Fix TX99 config option usage

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

ath9k: add TX99 support

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: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: check for NULL rate when using ieee80211_get_rts_cts_rate()

ieee80211_get_rts_cts_rate() can return NULL, so don't rely
on its members when it does return NULL.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: remove sc->config.cabqReadyTime

It is not exposed as a configuration option anyway

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

ath9k_hw: remove direct accesses to channel mode flags

Use wrappers where available. Simplifies code and helps with further
improvements to the channel data structure

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

ath9k: fix powersave response handling for BA session packets

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

ath9k: Use bitops for calibration flags

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

ath9k: add txq locking for ath_tx_aggr_start

Prevents race conditions when un-aggregated frames are pending in the
driver.

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

ath9k: don't use BAW tracking on PS responses for non-AMPDU packets

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

ath9k: do not link bf_next across multiple A-MPDUs

This might trip up tx completion processing, although the condition that
triggers this should not (yet) occur in practice.

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

ath9k: fix stale flag handling on buffer clone

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

ath9k: enable CSA functionality in ath9k

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: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: reset buffer stale flag in ath_tx_get_tid_subframe

If that flag stays set for a buffer that already ran through the tx path
once, it might cause issues in tx completion processing. Better clear it
early to ensure that this does not happen

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

ath9k: simplify ath_tid_drain

ath_tid_drain is only called when a station entry is being removed, so
there is no point in still tracking BAW state. Remove some unnecessary
code and a bogus TODO comment related to this.

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

ath9k: shrink a few data structures by reordering fields

Also reduce the size of a few fields where possible

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

ath9k: use software queueing for multicast traffic

Create a per-vif dummy node entry for keeping the multicast software
queues. This helps in setups with a lot of mulitcast traffic that could
otherwise potentially drown out unicast traffic to stations.

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

ath9k: improve tx scheduling fairness

Instead of trying to schedule the same TID multiple times in a loop,
iterate over other TIDs/stations first.

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

ath9k: use software queues for un-aggregated data packets

This is a first step for improving fairness between legacy and 802.11n
traffic, and it should also improve reliability of resets and channel
changes by keeping the hardware queue depth very short.

When an aggregation session is torn down, all packets in the retry queue
will be removed from the BAW and freed.

For all subframes that have not been transmitted yet, the A-MPDU flag
will be cleared, and a sequence number allocated. This ensures that the
next A-MPDU session will get the correct initial sequence number.
This happens both on aggregation session start and stop.

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

ath9k: always clear ps filter bit on new assoc

Otherwise in some cases, EAPOL frames might be filtered during the
initial handshake, causing delays and assoc failures.

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

ath9k: fix clearing expired A-MPDU subframes in tx completion

When the tid aggregation state has been marked as inactive, free
completed tx packets immediately. When a new aggregation session has not
been initialized yet, the BAW checks do not recognize it as expired.

Might fix potential stalls in setting up a new aggregation session.

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

ath9k: prepare queueing code for handling unaggregated traffic

- Allow ath_tx_get_tid_subframe to return non-AMPDU subframes.
- Reset the tid paused state on aggregation stop
- Initialize software queues even when HT is not supported

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

ath9k: fix block ack window tracking check

When a packet has been tracked as part of the BlockAck window and added
to the hardware queue, it can end up back in the TID queue again with
fi->retries still set to 0 (e.g. if the frame was filtered). Keep an
extra bit for the BAW tracking status to fix this corner case.

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

ath9k: simplify ath_tx_form_aggr

The check for ATH_AMPDU_SUBFRAME_DEFAULT is unnecessary, since it's set
to half the maximum BlockAck Window size, which is already the maximum
value that h_baw could possibly have. Also remove unnecessary variables.

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

ath9k: add function for getting the tx tid for a packet

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

ath9k: split tid retry packets into a separate queue

Improves packet retry order and helps with further tx queueing
improvements.

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

ath9k: add utility functions for accessing tid queues

Useful for further fixes / cleanups

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

ath9k: Fix RTS threshold

Currently, RTS threshold is not handled for HT. Handle
user-specified threshold values for both aggregated
and unaggregated frames. Use the wiphy's threshold
parameter for now, it can be made per-VIF later on.

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

ath9k: fix tx pending frames accounting for dropped packets

When dropping packets that have gone far enough into the tx path, the
pending frame counter needs to be decreased.

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

ath9k: fix queue depth accounting in ath_tx_txqaddbuf

ath_tx_txqaddbuf assumes that all the linked buffers in the queue passed
to it are part of the same A-MPDU or MPDU. The CAB queue rework violates
this assumption, which can cause the internal queue depth to go
negative.
Fix this by increasing the counter for all slots of [bf, bf->bf_lastbf]

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

ath9k: fix an RCU issue in calling ieee80211_get_tx_rates

ath_txq_schedule is called outside of the drv_tx call, so it needs RCU
protection.

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

ath9k: limit multicast buffer hardware queue depth

The CAB (Content after Beacon) queue is used for beacon-triggered
transmission of buffered multicast frames. If lots of multicast frames
were buffered and this queue fills up, it drowns out all regular
traffic. To limit the damage that buffered traffic can do, try to limit
the queued data to becaon_interval / 8.

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

ath9k: implement support for .release_buffered_frames()

This adds support for PS-Poll and U-APSD driver-buffered frames (part of
an aggregation session).

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

ath9k: add support for IEEE80211_TX_CTL_PS_RESPONSE

Use the UAPSD hardware queue to get PS-Poll responses out as fast as
possible and without backoff.

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

ath9k: prevent aggregation session deadlocks

Waiting for all subframes of an existing aggregation session to drain
before allowing mac80211 to start a new one is fragile and deadlocks
caused by this behavior have been observed.

Since mac80211 has proper synchronization for aggregation session
start/stop handling, a better approach to session handling is to simply
allow mac80211 to start a new session at any time. This requires
changing the code to discard any packets outside of the BlockAck window
in the A-MPDU software retry code.

This patch implements the above and also simplifies the code.

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

ath9k: fix draining aggregation tid buffers

After a tx attempt, an A-MPDU subframe can still have fi->retries at 0
(if the retry count wasn't incremented due to powersave).
In that case it is still tracked as part of the block ack window, so
when draining the tid queue, its sequence number needs to be cleared
from the pending frame bitmap.

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

ath9k: fix rate handling/reporting

This patch fixes some issues introduced in the rate control API rework.
When not running aggregation, copy bf->rates into info->control.rates
before applying the rate control status to it.
In ath_lookup_rate, the rates need to be pulled from bf->rates, not the
tx info.

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

ath9k: fix aggregation stop/flush handling

When aggregation stop is requested, don't run the mac80211 aggregation
stop callback yet, while the session is still blocked.
Also, when aggregation flush is requested, don't run the callback at all.

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

ath9k: add support for the new rate control API

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

ath9k: merge ath_tx_start_dma into ath_tx_start

The split makes no sense and merging the functions makes further changes
easier to implement

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

ath9k: implement buffer holding handling for EDMA FIFO

Inside one FIFO slot queue, EDMA chipsets have the same link pointer
re-read race condition as older chipsets, so the same buffer holding
logic needs to be used in order to avoid use-after-free bugs.
Unlike on older chips, it can be skipped for the end of the queue.

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

ath9k_common: remove ath9k_cmn_padpos

It is equivalent to ieee80211_hdrlen

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

ath9k: Fix ATH9K_HW_CAP_HT usage

There are a few places where the station's HT capabilities
should be checked instead of ATH9K_HW_CAP_HT, which is a global
feature for the driver. Fix this.

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

ath9k: use ath_tx_process_buffer instead of open-coding similar code

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

ath9k: clean up processing of pending tx frames on reset

Dropping packets from aggregation sessions is usually not a good idea, as
it might upset the synchronization of the BlockAck receive window of the
remote node. The use of the retry_tx parameter to reset/tx-drain functions
also seemed a bit arbitrary.
This patch removes this parameter altogether and ensures that pending tx
frames are not dropped for no good reason.

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

ath9k: use the devres API for allocations/mappings

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Acked-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Remove redundant NULL assignment

'bf_next' is cleared using ATH_TXBUF_RESET() in both the
callsites of ath_tx_get_buffer().

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

ath9k: Replace WME_NUM_TID with IEEE80211_NUM_TIDS

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

ath9k: Fix the 'xmit' debugfs file

The 'xmit' debugfs file has become big and unwieldy, fix
multiple issues with its usage:

* Store TX counters/statistics only for the 4 Access Categories.
Use IEEE80211_NUM_ACS instead of ATH9K_NUM_TX_QUEUES.

* Move various utility macros to debug.h, they can be reused
elsewhere.

* Remove tx_complete_poll_work_seen.

* Remove code that accesses various internal queue-specific
variables without any locking whatsoever. HW/SW queue details
will be handled in a subsequent patch.

* Do not print internal values like txq_headidx and txq_headidx.
They were mostly unused anyway, considering code like:
PRX("txq_tailidx: ", txq_headidx);

* Handle 'txprocdesc' for EDMA too.

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

ath9k/ath9k_htc: Remove WME macros

Use the macros provided by mac80211 and remove redundant
declarations inside the drivers.

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

ath9k: Test for TID only in BlockAcks while checking tx status

The ath9k xmit functions for AMPDUs can send frames as non-aggregate in case
only one frame is currently available. The client will then answer using a
normal Ack instead of a BlockAck. This acknowledgement has no TID stored and
therefore the hardware is not able to provide us the corresponding TID.

The TID set by the hardware in the tx status descriptor has to be seen as
undefined and not as a valid TID value for normal acknowledgements. Doing
otherwise results in a massive amount of retransmissions and stalls of
connections.

Users may experience low bandwidth and complete connection stalls in
environments with transfers using multiple TIDs.

This regression was introduced in b11b160defc48e4daa283f785192ea3a23a51f8e
("ath9k: validate the TID in the tx status information").

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Cc: stable@vger.kernel.org
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix stale pointers potentially causing access to free'd skbs

bf->bf_next is only while buffers are chained as part of an A-MPDU
in the tx queue. When a tid queue is flushed (e.g. on tearing down
an aggregation session), frames can be enqueued again as normal
transmission, without bf_next being cleared. This can lead to the
old pointer being dereferenced again later.

This patch might fix crashes and "Failed to stop TX DMA!" messages.

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

ath9k: use ieee80211_free_txskb

Using ieee80211_free_txskb for tx frames is required, since mac80211 clones
skbs for which socket tx status is requested.

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

ath9k: Fix chainmask selection for AR9462

Force chain 1 to be used for CCK rates since the target power
table stored in EEPROM is too high to transmit with both chains.
This is needed to avoid regulatory violation.

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

ath9k: Fix TX filter usage

The TX filter bit for a station would be set by the HW
when a frame is not acked. A frame would be completed with
ATH9K_TXERR_FILT status only when the corresponding filter bit
for the destination station is already set.

Currently, un-acknowledged packets are added to the pending queue
and retried, but the "clear_dest_mask" bit in the descriptor is
set only when the TX status has been ATH9K_TXERR_FILT. This results
in packet loss and the log shows:

wlan0: dropped TX filtered frame, queue_len=0 PS=0 @4309746071
wlan0: dropped TX filtered frame, queue_len=0 PS=0 @4309746076
wlan0: dropped TX filtered frame, queue_len=0 PS=0 @4309746377
...
...

This issue can be resolved by making sure that the destination
mask is cleared when the packet is being retried and the earlier
TX status is ATH9K_TXERR_XRETRY.

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

ath9k: fix PA linearization calibration related crash

Before PAPRD training can run, the card needs to have sent a packet for
thermal calibration. Sending a dummy packet with the PAPRD training flag
set causes a crash under some circumstance.
Fix the code by replacing the dummy tx with a delay that waits for a
real packet tx to have occurred.

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

mac80211: move TX station pointer and restructure TX

Remove the control.sta pointer from ieee80211_tx_info to free up
sufficient space in the TX skb control buffer for the upcoming
Transmit Power Control (TPC).
Instead, the pointer is now on the stack in a new control struct
that is passed as a function parameter to the drivers' tx method.

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Signed-off-by: Alina Friedrichsen <x-alina@gmx.net>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[reworded commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: Fix race in reset-work usage

Using work_pending() to defer certain operations when
a HW-reset work has been queued is racy since the check
would return false when the work item is actually in
execution. Use SC_OP_HW_RESET instead to fix this race.
Also, unify the reset debug statistics maintenance.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Cleanup beacon queue configuration

Setup the beacon queue parameters after disabling
interrupts. Also, remove the redundant call in conf_tx()
for IBSS mode since the queue would be configured
with the appropriate cwmin/cwmax values when beaconing
is enabled.

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

ath9k: fix aggregate size limit based on queue TXOP limit

If the aggregate size exceeds the TXOP limit, it leads to lots of unnecessary
hardware and software retries.

The previous 4ms frame limit table was completely undocumented, the commit
that updated it only vaguely referenced and equation from the standard,
but I've been unable to replicate its results.

Fix this by using a formula based on the code in ath_pkt_duration, which is
more likely to be correct for this case.

Reported-by: Dave Täht <dave.taht@gmail.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: make per-WMM-AC queue sizes configurable via debugfs

Prepare for using different queue size defaults for each AC.

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

ath9k: raise aggregation limit to 64k for HT IBSS

mac80211 adds stations in HT IBSS as soon as a frame comes by,
even if the HT capabilities are not known yet (they are often
received later, e.g. in beacons). So far, ampdu factor/density
are only calculated when the station is initially added.

This patch changes this to update ampdu factor/density settings
when starting a blockack session.

Using this patch, we had performance boosts from 60 to 150 MBit/s
between two 2x2 Atheros devices in 5 GHz HT IBSS mode.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix invalid pointer access in the tx path

After setup_frame_info has been called, only info->control.rates is still
valid, other control fields have been overwritten by the ath_frame_info
data. Move the access to info->control.vif for checking short preamble
to setup_frame_info before it gets overwritten.

This regression was introduced in commit d47a61aa
"ath9k: Fix multi-VIF BSS handling"

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Reported-by: Thomas Hühn <thomas@net.t-labs.tu-berlin.de>
Acked-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Cc: stable@vger.kernel.org [3.4]
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix a tx rate duration calculation bug

The rate pointer variable for a rate series is used in a loop before it is
initialized. This went unnoticed because it was used earlier for the RTS/CTS
rate. This bug can lead to the wrong PHY type being passed to the
duration calculation function.

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

ath9k: Fix powersave locking

The 'ps_flags' is used/accessed in a variety of contexts
and requires proper locking. Use 'sc_pm_lock' appropriately.

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

ath9k: Use atomic operations

The 'sc_flags' variable is being used in a number of places
with no locking whatsoever. This patch converts the usage
of sc_flags to atomic ops.

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

ath9k: Group link monitoring logic

Add link.c and move all the link/connection monitoring
code to it.

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

ath9k: fix a use-after-free-bug when ath_tx_setup_buffer() fails

ath_tx_setup_buffer() can fail if there is no ath_buf left, or if mapping DMA
failed. In this case it frees the skb passed to it.
If ath_tx_setup_buffer is called from ath_tx_form_aggr, the skb is still
linked into the tid buffer list and must be dequeued before being released.

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

ath9k: Fix TX fragmentation

Assigning sequence number for frames without taking care
of the fragment field breaks transmission of fragmented frames.
Fix this by assigning the fragment number properly.

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

ath9k_hw: remove ath9k_hw_gettxintrtxqs

The driver can just check the mask directly

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

ath9k_hw: clean up tx completion interrupt handling

TXQ_FLAG_TXOKINT_ENABLE and TXQ_FLAG_TXERRINT_ENABLE are always set and
used together, and they share the same bitmask in enum ath9k_tx_queue_flags.
Simplify the code that tests for these flags.

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

ath9k: Fix multi-VIF BSS handling

mac80211 provides short preamble information and ERP protection
information on a per-BSS basis, which can be used. Remove flags
stored in the driver, which was incorrect since they were being used
in a global manner.

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

ath9k: Remove aggregation flags

SC_OP_TXAGGR and SC_OP_RXAGGR are not really needed.
The HT capabilities of the station and HW can be used instead.

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

ath9k: fix drv_tx_last_beacon on AR9003 by processing beacon tx status

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

ath9k: Calculate ampdu limit using a helper

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

ath9k: fix tx queue sparse complaint

This fixes this rant from sparse:

CHECK drivers/net/wireless/ath/ath9k/xmit.c
drivers/net/wireless/ath/ath9k/xmit.c:107:13: warning: context imbalance in 'ath_txq_lock' - wrong count at exit
drivers/net/wireless/ath/ath9k/xmit.c:112:13: warning: context imbalance in 'ath_txq_unlock' - unexpected unlock
drivers/net/wireless/ath/ath9k/xmit.c:123:30: warning: context imbalance in 'ath_txq_unlock_complete' - unexpected unlock
CC [M] drivers/net/wireless/ath/ath9k/xmit.

Signed-off-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net: fix assignment of 0/1 to bool variables.

DaveM said:
Please, this kind of stuff rots forever and not using bool properly
drives me crazy.

Joe Perches <joe@perches.com> gave me the spatch script:

@@
bool b;
@@
-b = 0
+b = false
@@
bool b;
@@
-b = 1
+b = true

I merely installed coccinelle, read the documentation and took credit.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

ath9k: fix tx locking issues

The commit "ath9k: simplify tx locking" introduced a soft lockup triggered
by mac80211 sending a BAR frame triggered by a driver call to
ieee80211_tx_send_bar or ieee80211_tx_status.
Fix these issues by queueing processed tx status skbs and submitting them
to mac80211 outside of the lock.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath: Convert ath_dbg(bar, ATH_DBG_<FOO>, to ath_dbg(bar, FOO

Add ATH_DBG_ to macros to shorten the uses and
reduce the line count.

Coalesce ath_dbg formats.
Add missing spaces to coalesced formats.
Add missing newline terminations to ath_dbg formats.
Align ath_dbg arguments where appropriate.
Standardize ath_dbg formats without periods.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: avoid retransmitting aggregation frames that a BAR was sent for

The receiver will discard them anyway.

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

ath9k: simplify tx locking

Instead of releasing and taking back the lock over and over again in the
tx path, hold the lock a bit longer, requiring much fewer lock/unlock pairs.
This makes locking much easier to review and should not have any noticeable
performance/latency impact.

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

ath9k: remove bogus sequence number increment

tid->seq_next is initialized on A-MPDU start anyway, and the comment next
to this chunk of code seems to be bogus as well.

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

ath9k: reduce indentation level in a few places

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

ath9k: reduce the number of unnecessary BAR tx packets

When processing A-MPDU tx status, only send a BAR for the failed packet
with the highest sequence number.

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

ath9k: change maximum software retransmission handling

Instead of limiting a subframe to 10 A-MPDU software transmission attempts,
count hardware retransmissions as well and raise the limit a bit. That way
there will be fewer software retransmission attempts when traffic suffers
from lots of hardware retransmissions.

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

ath9k: always issue a full hw reset after waking up from full-sleep mode

After waking up from full sleep, registers are accessible, but rx/tx
typically fails. A fast channel change will not recover from this, so
ensure that a full-sleep -> wake transition is always followed by a full
reset.

The reason why this hasn't created any serious problems yet is that it's
hidden by the (wrong) behavior of enabling/disabling the radio when the
wiphy idle state changes.

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

ath9k: improve ath_tx_aggr_stop to avoid TID stuck in cleanup state

When tx agg is being stopped TID is flushed using ath_tx_flush_tid. It
is possible that ath_tx_flush_tid completelly flushes TID (if all
packets in this TID have already been retried). If this happened
ath_tx_aggr_stop would leave TID in cleanup state permanently.
Fix this by making ath_tx_flush_tid remove AGGR_ADDBA_COMPLETE and
AGGR_CLEANUP flags from TID status if TID is empty.

Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Add btcoex profile management support for AR9462

AR9462 chips have the capabilities to provoide bluetooth
profile information. For non-AR9462 btcoex chips, the BT
priority traffic was identified by periodically polling
the respective registers and updated dutycycle, stomptype,
etc. As AR9462 chip offers the BT profile informations,
let us make use of that to update aggregation limit,
dutycycle, stomptype and wieghtages.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix retry counting / BAR handling during queue flush

When tx is suspended temporarily and the queue is flushed, do not increase
the retry count or attempt to send out BAR frames. Instead simply retry
the affected subframes normally after the reset.

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

ath9k: improve PS filter clearing and retry counting for A-MPDU

Do not increment the retry counter if packets to a sleeping station
were not sent because of tx failure, instead of only checking the filter
flag.
Clear the PS filter only after an A-MPDU was reported as filtered,
otherwise the hardware might do some unnecessary extra retransmissions.

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

ath9k: keep track of what's triggering hardware resets

Export how many times each of the reset triggers has fired through debugfs.

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

ath9k: indicate which queues are blocked when stopping tx fails

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

ath9k: remove some bogus error handling code

If "axq_qnum >= ARRAY_SIZE(sc->tx.txq)", then the call to
ath9k_hw_releasetxqueue() would read beyond the end of the ah->txq[]
array and possibly corrupt memory. Fortunately,
ath9k_hw_setuptxqueue() doesn't return high values of "axq_qnum" and
this code can be removed.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: let drivers inform it about per TID buffered frames

For uAPSD implementation, it is necessary to know on
which ACs frames are buffered. mac80211 obviously
knows about the frames it has buffered itself, but
with aggregation many drivers buffer frames. Thus,
mac80211 needs to be informed about this.

For now, since we don't have APSD in any form, this
will unconditionally set the TIM bit for the station
but later with uAPSD only some ACs might cause the
TIM bit to be set.

ath9k is the only driver using this API and I only
modify it in the most basic way, it won't be able
to implement uAPSD with this yet. But it can't do
that anyway since there's no way to selectively
release frames to the peer yet.

Since drivers will buffer frames per TID, let them
inform mac80211 on a per TID basis, mac80211 will
then sort out the AC mapping itself.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Remove unnecessary AMPDU check at tx status

Fill the ampdu_[ack]_len for both aggregation and normal frames.
So that we could avoid unnecesary conditional at tx status.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: sync the dma buffer after changing the retry flag

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

ath9k: fix setting the IEEE80211_TX_CTL_CLEAR_PS_FILT flag

When the driver inserts padding between the 802.11 header and data, it
needs to set the hdr variable to the new header location.

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

Revert "ath9k: do not insert padding into tx buffers on AR9380+"

This reverts commit 4245d31347bdc99a608dc1d1cfe64e44aa3d1771.

ath9k: do not insert padding into tx buffers on AR9380+

With the new EDMA descriptor format, a single descriptor can contain up
to four buffer pointers. By splitting the buffer into two parts, we can
let the hardware add the padding internally instead of using memmove on
the skb data.

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

ath9k: optimize ath_tx_rc_status usage

The only flag that needs to be set when ath_tx_rc_status is called with
rc_update == false is the IEEE80211_TX_STAT_TX_FILTERED flag. All other
data is ignored in that case.
This flag can be set from ath_tx_complete_buf instead, so that we can
drop a few redundant calls to ath_tx_rc_status and remove the rc_update
function parameter

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

ath9k: remove a redundant check in ath_tx_form_aggr

ath_lookup_legacy now checks all the tx rate flags for MCS vs legacy

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

ath9k: use the new API for setting tx descriptors

With the new API, tx descriptors can be written in one single pass
instead of having to re-read and rewrite fields from multiple places.
This makes the code easier to read and also slightly improves performance
on embedded MIPS hardware.

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

ath9k: move ath_buf_set_rate to remove a forward declaration

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

ath9k: reduce the number of functions that access the tx descriptor

Makes it easier to clean up the ath9k_hw descriptor API

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

ath9k: remove ATH_TX_XRETRY and BUF_XRETRY flags

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

ath9k: always call ath_reset from workqueue context

This makes it much easier to add further rework to avoid race conditions
between reset and other work items.
Move other functions to make ath_reset static.

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

ath9k: eliminate common->{rx,tx}_chainmask

we already have ah->{rx,tx}chainmask for the same purpose

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

ath9k: fix checks for first subframe delimiter padding

The commit "ath9k_hw: Fix exceed transmission burst-time of 5GHz" added
a padding of 60 delimiters on the first subframe to work around an issue
on AR9380, but it lacked the checks to prevent it from being applied to
pre-AR9380, enterprise AR9380 or AR9580+

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: defer ath_tx_setup_buffer setup to the first tx attempt during aggr

With sequence number and buffer allocation deferred to when they're needed
for the first time, it becomes much easier to start dropping packets from
the tid queue if necessary, e.g. when latency suddenly increases. This can
lead to some future improvements in buffer management for better latency.

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

ath9k: move seqno allocation in the tx path to ath_tx_setup_buffer

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

ath9k: move the sequence number from ath_frame_info to ath_buf

It is only necessary for BAW tracking and moving it to the ath_buf
makes it easier to add further improvements, such as deferring
seqno allocation in the aggregation path.

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

ath9k: clean up the aggregation tid queue

Use a sk_buff_head instead containing skbs instead of a list_head
containing ath_bufs. This makes it easier to decouple the aggregation
code from the ath_buf struct

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

ath9k: fix regression in sending aggregated packets

The recent commit "ath9k: Send legacy rated frames as unaggregated"
introduced a check to ensure that packets with non-MCS rates set in
the rate series will not be aggregated. However, it failed to check
if the rate series is valid before testing the flags, thus breaking
aggregation for normal MCS-only packets if the last series is unset.

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

ath9k: Send legacy rated frames as unaggregated

Currently the aggregation is formed till the aggregation limit
is reached and the rate lookup is done for the first frame alone.
But there can be a legacy rated frames in tid queue. This patch
limits the subframe addition based on presence of legacy rate and
sends the legacy rated frames as unaggregated one.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Remove SC_OP_ENABLE_APM

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k_hw: Fix exceed transmission burst-time of 5GHz

The WAR which adds extra delimiters when using RTS/CTS
with aggregation and non-enterprise AR9003 chips.
This extra padding is done after doing all the 4ms limit
checks and hence the total aggregate sizes are exceeding
the allowed duration. This patch limits the aggregate
sizes appropriately after including these extra delimiters.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: avoid sending a-mpdu packets to sleeping stations

If the driver gets a tx status report for an A-MPDU sent to a station that
just went to sleep, that leaves a race condition where this tx status can
trigger another A-MPDU transmission.
To fix this, check if the station is sleeping before queueing the tid.

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

ath9k: Remove virtual wiphy specific frame type

This patch cleanups virtual wiphy specific frametype structure

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix sparse warnings

drivers/net/wireless/ath/ath9k/init.c:199:21: warning: context imbalance
in 'ath9k_reg_rmw' - different lock contexts for basic block
drivers/net/wireless/ath/ath9k/xmit.c:1175:31: warning: context
imbalance in 'ath_drain_txq_list' - unexpected unlock
drivers/net/wireless/ath/ath9k/xmit.c:2047:23: warning: context
imbalance in 'ath_tx_process_buffer' - unexpected unlock
drivers/net/wireless/ath/ath9k/ar9003_eeprom.c:3041:24: warning: cast to
restricted __le32

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix tx throughput drops for AR9003 chips with AES encryption

While sending aggregated frames in AES, the AR5416 chips
required additional padding b/w subframes. This workaround
is not needed for edma (AR9003 family) chips. With this patch
~4Mbps thoughput improvement was observed in clear environment.

Cc: stable@kernel.org
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix locking issue during tx completion

The received tx status of aggregated frame without BlockAck may
cause deaf state in AR5416 cards. So the driver does a reset to
recover. When this happens, we release the pcu_lock before doing
a reset as ath_rest acquires pcu_lock. This is ugly and also not
atomic. Fixing this addresses the TX DMA failure also.

ath_tx_complete_aggr can be called from different paths which
takes different variants of spin_lock. This patch also addresses
the following warning.

WARNING: at kernel/timer.c:1011 del_timer_sync+0x4e/0x50()
Call Trace:
<IRQ> [<ffffffff8104be3a>] warn_slowpath_common+0x7a/0xb0
[<ffffffff8104be85>] warn_slowpath_null+0x15/0x20
[<ffffffff8105915e>] del_timer_sync+0x4e/0x50
[<ffffffffa03726be>] ath_reset+0x3e/0x210 [ath9k]
[<ffffffff8135cdaf>] ? _raw_spin_unlock_bh+0x1f/0x30
[<ffffffffa037760a>] ath_tx_complete_aggr.isra.26+0x54a/0xa40 [ath9k]

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net: remove mm.h inclusion from netdevice.h

Remove linux/mm.h inclusion from netdevice.h -- it's unused (I've checked manually).

To prevent mm.h inclusion via other channels also extract "enum dma_data_direction"
definition into separate header. This tiny piece is what gluing netdevice.h with mm.h
via "netdevice.h => dmaengine.h => dma-mapping.h => scatterlist.h => mm.h".
Removal of mm.h from scatterlist.h was tried and was found not feasible
on most archs, so the link was cutoff earlier.

Hope people are OK with tiny include file.

Note, that mm_types.h is still dragged in, but it is a separate story.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ath9k: unify edma and non-edma tx code, improve tx fifo handling

EDMA based chips (AR9380+) have 8 Tx FIFO slots, which are used to fix the
tx queue start/stop race conditions which have to be worked around for
earlier chips by keeping the last descriptor in the queue. The current code
stores all frames that do not fit onto the 8 FIFO slots in a separate
list. Whenever a FIFO slot is freed up, the next frame (or A-MPDU) from the
pending queue gets moved to that slot.

This process is not only inefficient, but also unnecessary. The code can
be improved visibly by keeping the pending queue fully linked, and moving
the contents of the entire queue to a FIFO slot as it becomes available.

This patch makes the necessary changes for that and also merges some code
that was duplicated for EDMA vs non-EDMA. It changes txq->axq_link to point
to the last descriptor instead of the link pointer, so that
ath9k_hw_set_desc_link can be used, which works on all chips.

With this patch, a small performance increase for non-aggregated traffic
was observed on AR9380 based embedded hardware.

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

ath9k: Drag the driver to the year 2011

The Times They Are a-Changin'.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix a regression in PS frame filter handling

Only leave filtering enabled for AP or VLAN interfaces, clear the
destination mask for all other interfaces.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Reported-by: Ben Greear <greearb@candelatech.com>
Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k_hw: remove aggregation protection mode

when aggregation protection mode is enabled the hardware needs
to send RTS/CTS for each HT frame. Currently its disabled so
remove the unused call backs.

Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: cleanup hw pll work handler

There is no reason why pll work handler should be part of xmit
file. move it to main.c so that reading hw check routines are
all in the same place.

Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: assign keycache slots to unencrypted stations

Frame filtering relies on having a valid destination index (keycache slot),
to keep track of the destination. Assigning a keycache slot (configured
to unencrypted, with no key data attached) improves powersave handling in
AP mode with no encryption.
The dummy keycache entry for a station is cleared, when a real key gets
added.

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

ath9k: fix powersave frame filtering/buffering in AP mode

This patch fixes a long standing issue of pending packets in the queue being
sent (and retransmitted many times) to sleeping stations.
This was made worse by aggregation through driver-internal retransmitting
of A-MDPU subframes.
Previously the hardware tx filter was cleared unconditionally for every
single packet - with this patch it uses the IEEE80211_TX_CTL_CLEAR_PS_FILT
for unaggregated frames.
A sta_notify driver op is added to stop aggregation for stations when they
enter powersave mode. Subframes stay buffered inside the driver, to ensure
that the BlockAck window keeps a sane state.
Since the driver uses software aggregation, the clearing of the tx filter
needs to be handled by the driver instead of mac80211 for aggregated frames.

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

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

ath9k_hw: remove pCap->tx_triglevel_max

It has the same purpose (and value) as ah->config.max_txtrig_level

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

ath9k: remove the pending frames ath_txq_schedule workaround

This workaround called ath_txq_schedule whenever there were still pending
frames for a queue, but the queue depth was zero. Because of its its high
false positive probability (e.g. with paused TIDs) and because it is in
the way of other pending work (AP powersave fixes), it is better to remove
this code entirely.

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

ath9k: Fix kernel panic in AR2427

Kernel panic occurs just after AR2427 establishes connection with AP.
Unless aggregation is enabled we don't initialize the TID structure.
Thus accesing the elements of the TID structure when aggregation is
disabled, leads to NULL pointer dereferencing.

[ 191.320358] Call Trace:
[ 191.320364] [<fd250ea7>] ? ath9k_tx+0xa7/0x200 [ath9k]
[ 191.320376] [<fd1ec7fc>] ? __ieee80211_tx+0x5c/0x1e0 [mac80211]
[ 191.320386] [<fd1edd2b>] ? ieee80211_tx+0x7b/0x90 [mac80211]
[ 191.320395] [<fd1edddd>] ? ieee80211_xmit+0x9d/0x1d0 [mac80211]
[ 191.320401] [<c014218f>] ? wake_up_state+0xf/0x20
[ 191.320405] [<c015dbc8>] ? signal_wake_up+0x28/0x40
[ 191.320410] [<c012a578>] ? default_spin_lock_flags+0x8/0x10
[ 191.320420] [<fd1ee308>] ? ieee80211_subif_start_xmit+0x2e8/0x7c0
[mac80211]
[ 191.320425] [<c058f905>] ? do_page_fault+0x295/0x3a0
[ 191.320431] [<c04c4a3d>] ? dev_hard_start_xmit+0x1ad/0x210
[ 191.320436] [<c04d96b5>] ? sch_direct_xmit+0x105/0x170
[ 191.320445] [<fd1f161a>] ? get_sta_flags+0x2a/0x40 [mac80211]
[ 191.320449] [<c04c780f>] ? dev_queue_xmit+0x37f/0x4b0
[ 191.320452] [<c04d75b0>] ? eth_header+0x0/0xb0
[ 191.320456] [<c04cc479>] ? neigh_resolve_output+0xe9/0x310
[ 191.320461] [<c053d295>] ? ip6_output_finish+0xa5/0x110
[ 191.320464] [<c053e354>] ? ip6_output2+0x134/0x250
[ 191.320468] [<c053f7dd>] ? ip6_output+0x6d/0x100
[ 191.320471] [<c0559665>] ? mld_sendpack+0x395/0x3e0
[ 191.320475] [<c0557f81>] ? add_grhead+0x31/0xa0
[ 191.320478] [<c055a83c>] ? mld_send_cr+0x1bc/0x2b0
[ 191.320482] [<c01535d9>] ? irq_exit+0x39/0x70
[ 191.320485] [<c055a940>] ? mld_ifc_timer_expire+0x10/0x40
[ 191.320489] [<c015b92e>] ? run_timer_softirq+0x13e/0x2c0
[ 191.320493] [<c0103a30>] ? common_interrupt+0x30/0x40
[ 191.320498] [<c055a930>] ? mld_ifc_timer_expire+0x0/0x40
[ 191.320502] [<c0153358>] ? __do_softirq+0x98/0x1b0
[ 191.320506] [<c01534b5>] ? do_softirq+0x45/0x50
[ 191.320509] [<c0153605>] ? irq_exit+0x65/0x70
[ 191.320513] [<c05917dc>] ? smp_apic_timer_interrupt+0x5c/0x8b
[ 191.320516] [<c0103df1>] ? apic_timer_interrupt+0x31/0x40
[ 191.320521] [<c016007b>] ? k_getrusage+0x12b/0x2f0
[ 191.320525] [<c039e384>] ? acpi_idle_enter_simple+0x117/0x148
[ 191.320529] [<c04a20da>] ? cpuidle_idle_call+0x7a/0x100
[ 191.320532] [<c01021d4>] ? cpu_idle+0x94/0xd0
[ 191.320536] [<c057ab88>] ? rest_init+0x58/0x60
[ 191.320541] [<c07a58ec>] ? start_kernel+0x351/0x357
[ 191.320544] [<c07a53c7>] ? unknown_bootoption+0x0/0x19e
[ 191.320548] [<c07a50aa>] ? i386_start_kernel+0xaa/0xb1
[ 191.320550] Code: 03 66 3d 00 03 0f 84 7c 02 00 00 83 c3 18 0f b6 03
8b 4d e0 89 c3 83 e3 0f 6b c3 48 89 5d d8 8d 04 06 8d 50 0c 89 55 d0 8b
40 20 <8b> 00 3b 01 0f 85 8e 02 00 00 f6 47 20 40 0f 84 29 ff ff ff 8b
[ 191.320634] EIP: [<fd2586d4>] ath_tx_start+0x474/0x770 [ath9k] SS:ESP
0068:c0761a90
[ 191.320642] CR2: 0000000000000000
[ 191.320647] ---[ end trace 9296ef23b9076ece ]---
[ 191.320650] Kernel panic - not syncing: Fatal exception in interrupt

Cc: stable@kernel.org
Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix aggregation related interoperability issues

Some clients seems to keep track of their reorder window even after an
aggregation session has been disabled. This causes issues if there are
still retried but not completed frames pending for the TID.
To ensure that rx does not stall in such situations, set sendbar to 1
for any frame purged from the TID queue on teardown.

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

ath9k: fix the .flush driver op implementation

This patch simplifies the flush op and reuses ath_drain_all_txq for
flushing out pending frames if necessary. It also uses a global timeout
of 200ms instead of the per-queue 60ms timeout.

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

ath9k: fix stopping tx dma on reset

In some situations, stopping Tx DMA frequently fails, leading to messages
like this:

ath: Failed to stop TX DMA in 100 msec after killing last frame
ath: Failed to stop TX DMA!

This patch uses a few MAC features to abort DMA globally instead of iterating
over all hardware queues and attempting to stop them individually.
Not only is that faster and works with a shorter timeout, it also makes the
process much more reliable.

With this change, I can no longer trigger these messages on AR9380,
and on AR9280 they become much more rare.

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

ath9k: Implement op_flush()

When op_flush() is called with no drop (drop=false), the driver
tries to tx as many frames as possible in about 100ms on every
hw queue. During this time period frames from sw queue are also
scheduled on to respective hw queue.

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

ath9k: Remove redundant beacon_interval

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 57c4d7b4c4986037be51476b8e3025d5ba18d8b8.

Signed-off-by: Steve Brown <sbrown@cortland.com>
Reviewed-by: Mohammed Shafi <shafi.ath9k@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix possible double free of PAPRD skb's

This patch reverts the following commit
ath9k: remove bfs_paprd_timestamp from struct ath_buf_state

Under high interference/noisy environment conditions where PAPRD frames
fails heavily introduces a possibility of double freeing skb's and causes
kernel panic after some time.This patch reverts back to the original approach
of using paprd_timestamp before freeing the PAPRD frame skb's

[ 194.193705] Pid: 0, comm: swapper Tainted: G D WC
2.6.35-22-generic #33-Ubuntu
[ 194.193712] Call Trace:
[ 194.193722] [<c05c6468>] ? printk+0x2d/0x35
[ 194.193732] [<c05c63c3>] panic+0x5a/0xd2
[ 194.193741] [<c05ca3ed>] oops_end+0xcd/0xd0
[ 194.193750] [<c0105f74>] die+0x54/0x80
[ 194.193758] [<c05c9a16>] do_trap+0x96/0xc0
[ 194.193837] [<c0103fb0>] ? do_invalid_op+0x0/0xa0
[ 194.193846] [<c010403b>] do_invalid_op+0x8b/0xa0
[ 194.193856] [<c020bd4c>] ? kfree+0xec/0xf0
[ 194.193866] [<c012ce18>] ? default_spin_lock_flags+0x8/0x10
[ 194.193877] [<c01de47a>] ? free_one_page+0x12a/0x2d0
[ 194.193888] [<c01e04dc>] ? __free_pages+0x1c/0x40
[ 194.193897] [<c05c97a7>] error_code+0x73/0x78
[ 194.193906] [<c020bd4c>] ? kfree+0xec/0xf0
[ 194.193915] [<c04ecdd0>] ? skb_release_data+0x70/0xa0
[ 194.193924] [<c04ecdd0>] skb_release_data+0x70/0xa0
[ 194.193933] [<c04ec997>] __kfree_skb+0x17/0x90
[ 194.193941] [<c04eca31>] consume_skb+0x21/0x40
[ 194.193964] [<f85e0b70>] ieee80211_tx_status+0x760/0x860 [mac80211]
[ 194.193979] [<f85caddf>] ath_tx_complete_buf+0x1bf/0x2c0 [ath9k]
[ 194.193988] [<c05c8b9f>] ? _raw_spin_lock_irqsave+0x2f/0x50
[ 194.193997] [<c04ec40e>] ? skb_queue_tail+0x3e/0x50
[ 194.194010] [<f85cc803>] ath_tx_complete_aggr+0x823/0x940 [ath9k]
[ 194.194021] [<c0108a28>] ? sched_clock+0x8/0x10
[ 194.194030] [<c016bf14>] ? sched_clock_local+0xa4/0x180
[ 194.194040] [<c0139f57>] ? enqueue_sleeper+0x1e7/0x2b0
[ 194.194051] [<c013a194>] ? enqueue_entity+0x174/0x200
[ 194.194064] [<f85ce83d>] ath_tx_edma_tasklet+0x2bd/0x3b0 [ath9k]
[ 194.194074] [<c05c8b9f>] ? _raw_spin_lock_irqsave+0x2f/0x50
[ 194.194088] [<f85c7b9f>] ath9k_tasklet+0x9f/0x190 [ath9k]
[ 194.194097] [<c01505d7>] tasklet_action+0xa7/0xb0
[ 194.194107] [<c015127c>] __do_softirq+0x9c/0x1b0
[ 194.194117] [<c01a7f64>] ? irq_to_desc+0x14/0x20
[ 194.194126] [<c0124fc4>] ? ack_apic_level+0x64/0x1f0
[ 194.194136] [<c01513d5>] do_softirq+0x45/0x50
[ 194.194145] [<c0151545>] irq_exit+0x65/0x70
[ 194.194153] [<c05cf665>] do_IRQ+0x55/0xc0
[ 194.194162] [<c016a6c7>] ? hrtimer_start+0x27/0x30
[ 194.194171] [<c0103630>] common_interrupt+0x30/0x38
[ 194.194181] [<c012c21a>] ? native_safe_halt+0xa/0x10
[ 194.194268] [<c010a2f9>] default_idle+0x49/0xb0
[ 194.194277] [<c0101fcc>] cpu_idle+0x8c/0xd0
[ 194.194286] [<c05b2431>] rest_init+0x71/0x80
[ 194.194295] [<c081981a>] start_kernel+0x36e/0x374
[ 194.194305] [<c08199dd>] ? pass_all_bootoptions+0x0/0xa
[ 194.194314] [<c08190d7>] i386_start_kernel+0xd7/0xdf
[ 194.194364] panic occurred, switching back to text console

Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix a locking related issue.

Spin_lock has been tried to be acquired twice from ath9k_tasklet
to ath_reset which resulted in a machine freeze.

Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix a PLL hang issue observed with AR9485.

When this PLL hang issue is seen, both Rx and Tx fail to work.
The sqsum_dvc needs to be below 2000 for a good chip. During
this issue the sqsum_dvc value is beyond 80000 and only a
full reset can solve this problem.

Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix tx queue index confusion in debugfs code

Various places printing tx queue information used various different ways to
get a tx queue index for printing statistics. Most of these ways were wrong.

ATH_TXQ_AC_* cannot be used as an index for sc->tx.txq, because it is only
used internally for queue assignment.

One place used WME_AC_* as a queue index for sc->debug.stats.txstats, however
this array uses the ath9k_hw queue number as well.

Fix all of this by always using the ath9k_hw queue number as an index, and
always looking it up by going through sc->tx.txq_map.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fold struct ath_wiphy into struct ath_softc

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

ath9k: remove the bf->aphy field

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

ath9k: remove support for virtual wiphys

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

ath9k: clean up the code that wakes the mac80211 queues

Instead of spreading ath_wake_mac80211_queue() calls over multiple places
in the tx path that process the tx queue for completion, call it only
where the pending frames counter gets decremented, eliminating some
redundant checks.
To prevent queue draining from waking the queues prematurely (e.g. during
a hardware reset), reset the queue stop state when draining all queues,
as the caller in main.c will run ieee80211_wake_queues(hw) anyway.

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

ath9k: fix misplaced debug code

The commit 'ath9k: Add more information to debugfs xmit file.' added more
debug counters to ath9k and also added some lines of code to ath9k_hw.

Since ath9k_hw is also used by ath9k_htc, its code must not depend on ath9k
data structures. In this case it was not fatal, but it's still wrong, so
the code needs to be moved back to ath9k.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: clean up enums and unused macros

Remove unused macros and cleanup buffer_type enumeration

Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Try more than one queue when scheduling new aggregate.

Try all xmit queues until the hardware buffers are full.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Restart xmit logic in xmit watchdog.

The system can get into a state where the xmit queue
is stopped, but there are no packets pending, so
the queue will not be restarted.

Add logic to the xmit watchdog to attempt to restart
the xmit logic if this situation is detected.

Example 'dmesg' output:

ath: txq: f4e723e0 axq_qnum: 2, mac80211_qnum: 2 axq_link: f4e996c8 pending frames: 1 axq_acq empty: 1 stopped: 0 axq_depth: 0 Attempting to restart tx logic.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Add counters to distinquish AMPDU enqueues.

Show counters for pkts sent directly to hardware and
those queued in software.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Ensure xmit makes progress.

If the txq->axq_q is empty, the code was breaking out
of the tx_processq logic without checking to see if it should
transmit other queued AMPDU frames (txq->axq_acq).

This patches ensures ath_txq_schedule is called.

This needs review.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Add more information to debugfs xmit file.

Should help debug strange tx lockup type issues.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: add missing ps wakeup/restore calls

There are several places where ath_reset() was called without proper
calls to ath9k_ps_wakeup/ath9k_ps_restore. To fix this, add those calls
directly to ath_reset and drop them from callers where it makes sense.

Also add them to the config callback around ath_update_txpow to fix a
crash that happens when the tx power changed before any vif is brought up.

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

ath9k: fix excessive BAR sending when a frame exceeds its retry limit

Because the sendbar variable was not reset to zero, the stack would send
Block ACK requests for all subframes following the one that failed, which
could mess up the receiver side block ack window.

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

ath9k: try more than one tid when scheduling a new aggregate

Sometimes the first TID in the first AC's list is not available for forming
a new aggregate (the BAW might not allow it), however other TIDs may have
data available for sending.
Prevent a slowdown of other TIDs by going through multiple entries until
we've either hit the last one or enough AMPDUs are pending in the hardware
queue.

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

ath9k: reinitialize block ack window data when starting aggregation

There might be some old stale data left, which could confuse tracking
of pending tx frames.

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

ath9k: fix initial sequence number after starting an ampdu session

txtid->seq_start may not always be up to date, when there is HT non-AMPDU
traffic just before starting an AMPDU session. Relying on txtid->seq_next
is better, since it is also used to generate the sequence numbers for
all QoS data frames.

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

ath9k: fix bogus sequence number increases on aggregation tid flush

When a tid pointer is passed to ath_tx_send_normal(), it increases the
starting sequence number for the next AMPDU action frame, which should
only be done if the sequence number assignment is fresh. In this case
it is clearly not.

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

ath9k: fix queue depth check for forming new aggregates

To improve aggregation length, there should not be more than two fully formed
A-MPDU frames in the hardware queue. To ensure this, the code checks the tx
queue length before forming new A-MPDUs. This can reduce the throughput (or
maybe even starve out A-MPDU traffic) when too many non-aggregated frames are
in the queue.
Fix this by keeping track of pending A-MPDU frames (even when they're sent out
as single frames), but exclude rate control probing frames to improve
performance.

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

ath9k: fix sequence number assigment for non-AMPDU QoS data frames

wireless-testing commit 04caf863750bc7e042d1e8d57e5ce9d6326ab435
('ath9k: more tx setup cleanups') merged tx path code for HT vs
non-HT frames, however it did not pass the tid pointer to
ath_tx_send_normal, causing an inconsistency between AMPDU vs
non-AMPDU sequence number handling.
Fix this by always passing in the tid pointer for all QoS data frames.

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

ath9k: Check for NULL sta in ath_tx_start

It can be NULL according to docs, and logging showed it
to be NULL in practice.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath: Convert ath_print to ath_dbg

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: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath: Convert ath_print(.., ATH_DBG_FATAL to ath_err

So these errors are always emitted at KERN_ERR level.
Remove ARRAY_SIZE casts, use printf type %zu

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix a DMA related race condition on reset

When ath_drain_all_txq fails to stop DMA, it issues a hw reset. This reset
happens at a very problematic point in time, when the hardware rx path has
not been stopped yet. This could lead to memory corruption, hardware hangs
or other issues.
To fix these issues, simply remove the reset entirely and check the tx DMA
stop status to prevent problems with fast channel changes.

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

ath9k: Add support for Adaptive Power Management

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: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Tested-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix software retry counter tracking

The recent tx path cleanups moved the software retry count tracking
from the ath_buf to the skb cb, however the actual counter update
referred to the wrong location, confusing block-ack window tracking.
Fix this by using the retries counter in the struct ath_frame_info.

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

ath9k: fix recursive locking in the tx flush path

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: store frame information used by aggregation inside the skb tx info

Since the pointers after the rates in the tx info cannot be used anymore
after frames have been queued, this area can be used to store information
that was previously stored in the ath_buf. With these changes, we can delay
the ath_buf assignment in the aggregation code until aggregates are formed.

That will not only make it possible to simplify DMA descriptor setup to
do less rewriting of uncached memory, but will also make it easier to
move aggregation out of the core of the ath9k tx path.

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

ath9k: more tx setup cleanups

- remove the BUF_HT flag, and instead check for IEEE80211_TX_CTL_AMPDU
before calling ath_tx_send_ampdu.
- remove a few unused variables
- calculate frame length before adding the frame padding
- merge the misnamed ath_tx_start_dma function into ath_tx_start
- remove an unused argument for assign_aggr_tid_seqno

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

ath9k: clean up code duplication around ath_tx_start

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

ath9k: remove bf_tx_aborted from struct ath_buf

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

ath9k: remove bfs_frmlen from struct ath_buf_state

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

ath9k: remove bfs_nframes from struct ath_buf_state

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

ath9k: remove bfs_al from struct ath_buf_state

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

ath9k: remove bfs_keyix from struct ath_buf_state

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

ath9k: remove bfs_paprd_timestamp from struct ath_buf_state

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

ath9k: remove bfs_keytype from struct ath_buf_state

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

ath9k: remove bfs_tidno from struct ath_buf_state

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

ath9k: remove bfs_seqno from struct ath_buf_state

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

ath9k: fix PA predistortion training frame setup

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

ath9k: clean up tx buffer setup

Merge ath_tx_send_normal and ath_tx_send_ht_normal.
Move the paprd state initialization and sequence number assignment
to reduce the number of redundant checks.

This not only simplifies buffer allocation error handling, but also
removes a small inconsistency in the buffer HT flag.
This flag should only be set if the frame is also a QoS data frame.

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

ath9k: remove the tx info padding byte abuse

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

ath9k: handle tx underrun in the driver instead of rate control

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

ath9k: remove the unnecessary private xretry tx flag

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

ath9k: rework tx queue selection and fix queue stopping/waking

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: Felix Fietkau <nbd@openwrt.org>
Reported-by: Björn Smedman <bjorn.smedman@venatech.se>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: content DMA start / stop through the PCU lock

This helps align resets / RX enable & disable / TX stop / start.
Locking around the PCU is important to ensure the hardware doesn't
get stale data when working with DMA'able data.

This is part of a series of patches which fix stopping
TX DMA completley when requested on the driver.
For more details about this issue refer to this thread:

http://marc.info/?l=linux-wireless&m=128629803703756&w=2

Tested-by: Ben Greear <greearb@candelatech.com>
Cc: Kyungwan Nam <kyungwan.nam@atheros.com>
Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: move the PCU lock to the sc structure

The PCU lock should be used to contend TX DMA as well,
this will be done next.

This is part of a series of patches which fix stopping
TX DMA completley when requested on the driver.
For more details about this issue refer to this thread:

http://marc.info/?l=linux-wireless&m=128629803703756&w=2

Tested-by: Ben Greear <greearb@candelatech.com>
Cc: Kyungwan Nam <kyungwan.nam@atheros.com>
Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: simplify hw reset locking

The new PCU lock is better placed so we can just contend
against that when trying to reset hardware.

This is part of a series of patches which fix stopping
TX DMA completley when requested on the driver.
For more details about this issue refer to this thread:

http://marc.info/?l=linux-wireless&m=128629803703756&w=2

Tested-by: Ben Greear <greearb@candelatech.com>
Cc: Kyungwan Nam <kyungwan.nam@atheros.com>
Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix tx aggregation flush on AR9003

Completing aggregate frames can lead to new buffers being pushed into
the tid queues due to software retransmission.
When the tx queues are being drained, all pending aggregates must be
completed before the tid queues get drained, otherwise buffers might be
leaked.

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

ath9k: resume aggregation immediately after a hardware reset

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

ath9k: fix handling of rate control probe frames

The ath9k aggregation code was already checking the rate control probe flag
to prevent starting an aggregate frame with a sampling rate. What was missing
was closing an aggregate before adding a probing frame to it.
Without that, rate control cannot have precise control over probing, which
delays using faster rates when the channel conditions improve.

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

ath9k: Null out references to stale pointers.

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: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Remove bf_dmacontext.

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: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Fix potential use-after-free.

The ath_debug_stat_tx references bf->bf_mpdu, which
is the skb consumed by ath_tx_complete. So, call
the ath_debug_stat_tx method first.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: A-MPDU rate control info fix

This patch fixes the following problems with the rate control feedback
generated by ath9k for A-MPDU frames:

1. Rate control feedback is carried on the first frame of an aggregate
that is either ACKed, or has execeeded the software retry count and is
considered failed. However, ath9k would incorrectly assume the aggregate
had the length 1 if one of these conditions did not apply to the first
frame of the aggregate, but instead a later frame. This fix therefor
copies the bf_nframes field of the buffer in the same manner as the rates
field of the tx status.

2. Sometimes the ampdu_len and ampdu_ack_len fields of the tx status was
left uninitialized eventhough the IEEE80211_TX_STAT_AMPDU flag was set.
This is now avoid by setting flag and fields in the same place.

3. Even if a frame has been selected for aggregation by mac80211 and
marked with the IEEE80211_TX_CTL_AMPDU flag it can sometimes happen that
ath9k transmits the frame without aggregation. In these cases the
ampdu_ack_len field could be incorrectly computed because the nbad
parameter to ath_tx_rc_status was incorrect.

Cc: <stable@kernel.org>
Signed-off-by: Björn Smedman <bjorn.smedman@venatech.se>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: remove unnecessary power save flags.

drv_config callback is called only after the ack for the nullframe
is received and so driver need not do anything special for this.

So remove NULLFUNC_COMPLETED, PS_ENABLED flags and bf_isnullfunc
flags from ath9k as mac80211 already handles them properly.

Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211/ath9k: Support AMPDU with multiple VIFs.

The old ieee80211_find_sta_by_hw method didn't properly
find VIFS when there was more than one per AP. This caused
AMPDU logic in ath9k to get the wrong VIF when trying to
account for transmitted SKBs.

This patch changes ieee80211_find_sta_by_hw to take a
localaddr argument to distinguish between VIFs with the
same AP but different local addresses. The method name
is changed to ieee80211_find_sta_by_ifaddr.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: move ath_tx_aggr_check() to the rate control module

It is not used anywhere else and can be made static

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

ath9k: clean up / fix aggregation session flush

The tid aggregation cleanup is a bit fragile, as it discards failed
subframes in some places, and retransmits them in others. This could
block the cleanup of an existing aggregation session, if a retransmission
for a tid is issued, yet the tid is never scheduled again because of
the cleanup state.

Fix this by getting rid of as many subframes as possible, as early
as possible, and immediately transmitting pending subframes as regular
HT frames instead of waiting for the cleanup to complete.

Drop all pending subframes while keeping track of the Block ACK window
during aggregate tx completion to prevent sending out stale subframes,
which could confuse the receiver side.

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

ath9k: fix an aggregation start related race condition

A new aggregation session start can be issued by mac80211, even when the
cleanup of the previous session has not completed yet. Since the data structure
for the session is not recreated, this could corrupt the block ack window
and lock up the aggregation session. Fix this by delaying the new session
until the old one has been cleaned up.

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

ath9k: clean up block ack window handling

There's no reason to keep pointers to pending tx buffers around, if they're
only used to keep track of which frames are still pending. Use a bitfield
instead.

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

ath9k: remove duplicate get_hw_crypto_keytype()

Use ath9k_cmn_get_hw_crypto_keytype() instead which is
already exported and shared, and does exactly the same thing.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix an issue in ath_atx_tid paused flag management

I noticed a possible issue in the paused flag management of the
ath_atx_tid data structure. In particular, in a noisy environment and
under heavy load, I observed that the AGGR session establishment could
fail several times consecutively causing values of the paused flag
greater than one for this TID (ath_tx_pause_tid is called more than
once from ath_tx_aggr_start).

Considering that the session for this TID can not be established also
after the mac80211 stack calls the ieee80211_agg_tx_operational() since
the ath_tx_aggr_resume() lowers the paused flag only by one.

This patch also replaces some BUG_ON calls with WARN_ON, as even if
these unlikely conditions happen, it's not fatal enough to justify a
BUG_ON.

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k_hw: clean up per-channel calibration data

The noise floor history buffer is currently not kept per channel, which
can lead to problems when changing channels from a clean channel to a
noisy one. Also when switching from HT20 to HT40, the noise floor
history buffer is full of measurements, but none of them contain data
for the extension channel, which it needs quite a bit of time to recover
from.

This patch puts all the per-channel calibration data into a single data
structure, and gives the the driver control over whether that is used
per-channel or even not used for some channels.

For ath9k_htc, I decided to keep this per-channel in order to avoid
creating regressions.

For ath9k, the data is kept only for the operating channel, which saves
some space. ath9k_hw takes care of wiping old data when the operating
channel or its channel flags change.

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

ath9k: fix yet another buffer leak in the tx aggregation code

When an aggregation session is being cleaned up, while the tx status
for some frames is being processed, the TID is flushed and its buffers
are sent out.

Unfortunately that left the pending un-acked frames unprocessed, thus
leaking buffers. Fix this by reordering the code so that those frames
are processed first, before the TID is flushed.

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

ath9k: Fix inconsistency between txq->stopped and the actual queue state

Sometimes txq state(txq->stopped) can be marked as started but the actual
queue may not be started (in ATH_WIPHY_SCAN state, for example). Fix this.

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

ath9k: another fix for the A-MPDU buffer leak

The patch 'ath9k: fix a buffer leak in A-MPDU completion' addressed the
issue of running out of buffers/descriptors in the tx path if a STA is
deleted while tx status feedback is still pending.
The remaining issue is that the skbs of the buffers are not reclaimed,
leaving a memory leak.
This patch fixes this issue by running the buffers through
ath_tx_complete_buf(), ensuring that the pending frames counter is also
updated.

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

ath9k: validate the TID in the tx status information

Occasionally the hardware can send out tx status information with the wrong
TID. In that case, the BA status cannot be trusted and the aggregate
must be retransmitted.

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

ath9k: fix a buffer leak in A-MPDU completion

When ath_tx_complete_aggr() is called, it's responsible for returning
all buffers in the linked list. This was not done when the STA lookup
failed, leading to a race condition that could leak a few buffers when
a STA just disconnected.
Fix this by immediately returning all buffers to the free list in this case.

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

ath9k: fix a potential buffer leak in the STA teardown path

It looks like it might be possible for a TID to be paused, while still
holding some queued buffers, however ath_tx_node_cleanup currently only
iterates over active TIDs.
Fix this by always checking every allocated TID for the STA that is being
cleaned up.

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

ath9k: fix retry count for A-MPDU rate control status reports

The 'bf_retries' field of the ath_buf structure was used for both
software retries (AMPDU subframes) and hardware retries (legacy
frames). This led to a wrong retry count being reported for the A-MPDU
rate control stats.
This patch changes the code to no longer use bf_retries for reporting
retry counts, but instead always using the real on-chip retry count
from the ath_tx_status.
Additionally, if the first subframe of an A-MPDU was not acked, the tx
status report is submitted along with the first acked subframe, which
may not contain the correct rates in the tx info.
This is easily corrected by saving the tx rate info before looping over
subframes, and then copying it back once the A-MPDU status report is
submitted.
In my tests this change improves throughput visibly.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Reported-by: Björn Smedman <bjorn.smedman@venatech.se>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: Remove unused paprd_txok

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

ath9k: Fix bug in paprd

It is possbile that the transmission of paprd test frame
might not get completed in 100ms if tx is stuck. Freeing
this skb upon timeout in ath_paprd_calibrate() will result
in accessing already freed memory when the associated pending
buffer is drained in txq. This patch fixes this issue.

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

ath9k: implement PA predistortion support

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: fix queue stopping threshold

ath9k tries to prevent WMM queue tx buffer starvation caused by
traffic on different queues by limiting the number of pending frames
in a tx queue (tracked in the ath_buf structure). This had a leak
issue, because the a skb can be reassigned to a different ath_buf
in the tx path, causing the pending frame counter to become inaccurate.

To fix this, track the number of frames in an array in the softc,
using the mac80211 queue mapping as index.

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

ath9k: remove duplicate WMM AC definitions

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

ath9k: fix mac80211 queue lookup for waking up queues

ath_get_mac80211_qnum() expects the queue 'subtype'
(internal ID for the WMM AC) as argument when looking up
the mac80211 queue, however ath_wake_mac80211_queue provides
txq->axq_qnum instead, which contains the hardware queue
number. Fix this by keeping track of the WMM class ID in
the txq data structure.

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

ath9k: fix queue stop/start based on the number of pending frames

Because there is a limited number of tx buffers available, once the
queue has been filled to a certain point, ath9k needs to stop accepting
new frames from mac80211. In order to prevent a full WMM queue from
stopping another queue with fewer frames, this patch limits the number
of queued frames to a quarter of the total available tx buffers, minus
some reserved frames to be used for other purposes (e.g. beacons).

Because tx buffers are reserved for frames when they're staged in
software queues as well, the actual queue depth cannot be used for
this, so this patch stores a reference to the tx queue in the ath_buf
struct and keeps track of the total number of pending frames.

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

ath9k: Make sure null func frame is acked before going into PS for ar9003

Add missing code to handle nullfunc frame completion in
ath_tx_edma_tasklet().

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

ath9k: Fix bug in the way "bf_tx_aborted" of struct ath_buf is used

This bug was introduced by the following commit

Author: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Date: Thu Apr 15 17:38:46 2010 -0400

ath9k: Remove ATH9K_TX_SW_ABORTED and introduce a bool for this purpose

Wrong buffer is checked for bf_tx_aborted field in ath_tx_num_badfrms(),
this may result in a rate scaling with wrong feedback (number
of unacked frames in this case). It is the last one in the chain
of buffers for an aggregate frame that should be checked.

Also it misses the initialization of this field in the buffer,
this may lead to a situation where we stop the sw retransmission
of failed subframes associated to this buffer.

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

ath9k: Fix ath_print in xmit for hardware reset.

ath_print in xmit.c should say "Reseting hardware"
instead of Resetting HAL!(since HAL is being fazed out).
dmesg shows:
[ 8660.899624] ath: Failed to stop TX DMA in 100 msec after killing last frame
[ 8660.899676] ath: Unable to stop TxDMA. Reset HAL!

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>