Re: [ath5k-devel] [PATCH v2] ath5k: disable ASPM

[Maxim Levitsky <maximlevitsky@gmail.com>]

On Mon, 2010-06-21 at 13:37 -0700, Luis R. Rodriguez wrote: 
> On Mon, Jun 21, 2010 at 1:16 PM, Maxim Levitsky <maximlevitsky@gmail.com> wrote:
> > Luis, let me explain again, exactly the situation:
> >
> > First of all AR5001 and AR5001X devices (former was usualy listed as
> > AR2425, and I have it, later I don't know about much), don't work well
> > with ASPM L0s enabled.
> 
> Thanks for the clarification. David, do you see this as well on your end?
> 
> > I told that many times, but I tell again.
> > As soon as card it put on medium to high transmit load
> > (for example even if transmission consists mostly of TCP ACK packets),
> > it dies.
> >
> > Usualy it will stop transmitting, and then after few seconds it will
> > send RXORN intrrupt to the host, even though the channel was idle.
> > (Tested by sending a stream of UDP packets on channel that is neighbor
> > free).
> >
> > I didn't see it, but some users reported seeing jumbo frames at this
> > time as well.
> > Overall it doesn't matter because card just goes south.
> >
> > A reset sometimes brings card to life, sometimes causes another storm of
> > RXORN and sometimes just results in quiet dead card.
> > A next reset might bring it to life, or not.
> >
> > Card (at least mine) advertises its as a 'pre pci 1.1 device'.
> > Therefore if I enable CONFIG_PCIEASPM, the pci core will automaticly
> > disable ASPM (both L0s and L1) on this card.
> > I won't be surprised that windows does the same.
> 
> I am not sure when L0s was enabled as per the spec as mandatory, I
> thought it was optional. Interesting to hear this behavior on Linux
> with CONFIG_PCIEASPM. That Kconfig description and code really need
> some spit shining.
> 
> > Therefore the patch I sent it useless because it only works when
> > CONFIG_PCIEASPM is enabled.
> 
> How so ? Your patch disables L0s, I can use ASPM with L0s and L1 with
> or without CONFIG_PCIEASPM. If I added your calls to ath9k I would
> disable L0s.
Because due to card advertisement, CONFIG_PCIEASPM already disables L0s
and L1 on the card, therefore my patch does nothing.



Best regards,
Maxim Levitsky