[ath9k-devel] ath9k: spurious queue reset (beacon stuck) when joining an IBSS.

[Nicolas Cavallari <Nicolas.Cavallari@lri.fr>]

[resending, as no archive saw my previous message]

With an AR9382 (well, i think, its PCI-id is 168c:0030 rev 1/168c:3116),
each time I join an IBSS network, the driver repeatedly
resets the queue for a while, because of too many missed beacons.  After
some time, this stops and the card behave normally.  But many packets
are lost in the process.

The problem seems to aggravate when the number of IBSS nodes is higher :
When joining a IBSS network with only one node, Only a few (e.g. 4)
beacons are lost, and no reset takes places. When joining an IBSS
network with two nodes, the queues can be reset up to 224 times in 20
seconds. When joining large IBSS networks, it sometimes never stop
resetting.  Occasionally, when resetting, the driver fails to reset TX DMA

If i hack the driver to not reset when the beacon is stuck, the beacon
tx resumes quickly by itself after 80-200 misses and the network seems
to work normally (if not better). On large&clogged ad-hoc networks, the
card sometimes miss between 1 and 80 beacons, but it might be due to
background scanning i think.

What could be the problem here ? is ad-hoc beaconing kind of broken ?
I do not have the problem with AR9285.

Logs with compat-wireless 2012-09-16 showing an iteration of the reset
loop :

[346208.955736] ath: phy0: TS Start 0x35ac8000 End 0x35acc800 Virt
f5ac8000, Size 512
[346208.957662] ath: phy0: Enabled BB Watchdog timeout (25 ms)
[346208.957832] ath: phy0: IBSS nexttbtt: 102400 intval: 102400
conf_intval: 100
[346208.957876] ath: phy0: Set queue properties for: 9
[346208.957886] ath: phy0: Reset TX queue: 9
[346209.019579] ath: phy0: transmitting packet, skb: edc5a480
[346209.019600] ath: phy0: qnum: 2, txq depth: 0
[346209.019612] ath: phy0: TXDP[2] = 3082ff80 (f082ff80)
[346209.020968] ath: phy0: TX complete: skb: edc5a480
[346209.046911] ath: phy0: slot 0, tsf: 347602220263
[346209.046946] ath: phy0: Transmitting beacon for slot: 0
[346209.047083] ath: phy0: MAC Hang signature not found at DCU complete
[346209.047108] ath: phy0: missed 1 consecutive beacons
[346209.048182] ath: phy0: MAC Hang signature not found at DCU complete
[346209.048194] ath: phy0: missed 2 consecutive beacons
[346209.049231] ath: phy0: MAC Hang signature not found at DCU complete
[346209.049259] ath: phy0: missed 3 consecutive beacons
[346209.050449] ath: phy0: MAC Hang signature not found at DCU complete
[346209.050475] ath: phy0: missed 4 consecutive beacons
[346209.051748] ath: phy0: MAC Hang signature not found at DCU complete
[346209.051776] ath: phy0: missed 5 consecutive beacons
[346209.052776] ath: phy0: MAC Hang signature not found at DCU complete
[346209.052789] ath: phy0: missed 6 consecutive beacons
[346209.053789] ath: phy0: MAC Hang signature not found at DCU complete
[346209.053802] ath: phy0: missed 7 consecutive beacons
[346209.054817] ath: phy0: MAC Hang signature not found at DCU complete
[346209.054848] ath: phy0: missed 8 consecutive beacons
[346209.056082] ath: phy0: MAC Hang signature not found at DCU complete
[346209.056108] ath: phy0: beacon is officially stuck
[346209.056152] ath: phy0: reset work is pending, skip beaconing now
[346209.069038] ath: phy0: Reset TX queue: 0
[346209.069051] ath: phy0: Reset TX queue: 1
[346209.069061] ath: phy0: Reset TX queue: 2
[346209.069070] ath: phy0: Reset TX queue: 3
[346209.069080] ath: phy0: Reset TXQ, inactive queue: 4
[346209.069087] ath: phy0: Reset TXQ, inactive queue: 5
[346209.069095] ath: phy0: Reset TXQ, inactive queue: 6
[346209.069102] ath: phy0: Reset TXQ, inactive queue: 7
[346209.069110] ath: phy0: Reset TX queue: 8
[346209.069125] ath: phy0: Reset TX queue: 9
[346209.069158] ath: phy0: ah->misc_mode 0x10000004
[...]