ML403, root=/dev/xsa3 rw, bonnie++

[Grant Likely]

On 4/24/07, Andrei Konovalov <akonovalov at ru.mvista.com> wrote:
> Hi Grant,
>
> I've discovered the IBM Microdrive fits perfectly into the ML403 CF slot :)
> So I've repeated the bonnie++ stress test on ML403 with the hard disk.
> The log is below.
> The test completed OK, but there was one message from the driver in the middle
> of the test:
> "[  776.712206] xsysace xsa: kicking stalled fsm; state=3 task=3 iter=7829 dc=0"

I added a kernel timer to the sysace driver to give the state machine
a nudge if there is no activity after a short amount of time; for
example, if an interrupt is missed.  It is a rare condition, but if it
happens, then the timer keeps the driver from hanging up completely.

I don't know how to avoid the condition.  It seems to be related to
the CFBSY and DATARDY status bits.  It seems that sometimes the sysace
raises a DATARDY irq, but the driver cannot do anything because CFBSY
is set.  Then, after clearing that condition and yielding for a bit a
subsequent DATARDY irq is lost and the state machine stalls.

Thanks for the testing, it's a big help.

Cheers,
g.

-- 
Grant Likely, B.Sc. P.Eng.
Secret Lab Technologies Ltd.
grant.likely at secretlab.ca
(403) 399-0195