kern/45903: ath supports Atheros 9285, but presents timeout messages

[arthurmaciel%gmail.com@localhost]

>Number:         45903
>Category:       kern
>Synopsis:       ath supports Atheros 9285, but presents timeout messages
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          support
>Submitter-Id:   net
>Arrival-Date:   Wed Feb 01 01:10:00 +0000 2012
>Originator:     Arthur
>Release:        5.99.6
>Organization:
>Environment:
NetBSD thunder 5.99.60 NetBSD 5.99.60 (GENERIC) #0: Mon Jan 16 20:19:16 UTC 
2012  
builds%b6.netbsd.org@localhost:/home/builds/ab/HEAD/i386/201201161300Z-obj/home/builds/ab/HEAD/src/sys/arch/i386/compile/GENERIC
 i386
>Description:
NetBSD 5.1 does not support Atheros 9285, but -current (5.99.6) does. 

However it presents this spontaneously from time to time (txintrperiod varies):

ath0: device timeout (txq 1, txintrperiod 5)
ath0: device timeout (txq 1, txintrperiod 4)
ath0: device timeout (txq 1, txintrperiod 3)
ath0: device timeout (txq 1, txintrperiod 2)

Medium priority is justified by manual pages say (note last sentence):
"ath%d: device timeout  A frame dispatched to the hardware for transmission did 
not complete in time.  The driver will reset the hardware and continue. This 
should not happen."

and because of lags:

$ ping yahoo.com
PING yahoo.com (209.191.122.70): 52 data bytes
64 bytes from 209.191.122.70: icmp_seq=0 ttl=48 time=196.944 ms
64 bytes from 209.191.122.70: icmp_seq=2 ttl=48 time=219.091 ms
64 bytes from 209.191.122.70: icmp_seq=6 ttl=47 time=195.358 ms
64 bytes from 209.191.122.70: icmp_seq=8 ttl=47 time=191.264 ms
64 bytes from 209.191.122.70: icmp_seq=9 ttl=48 time=202.473 ms
64 bytes from 209.191.122.70: icmp_seq=10 ttl=47 time=198.441 ms
64 bytes from 209.191.122.70: icmp_seq=11 ttl=47 time=199.610 ms
^C
----yahoo.com PING Statistics----
12 packets transmitted, 7 packets received, 41.7% packet loss
round-trip min/avg/max/stddev = 191.264/200.455/219.091/8.934 ms

Thank you!
>How-To-Repeat:
Just boot with this card and kernel 5.99.6 and wait to see at console or at 
dmesg output.
>Fix: