Re: [RFC][PATCH] thunderbolt: icm: Ignore mailbox errors in icm_suspend()

[Mika Westerberg <mika.westerberg@linux.intel.com>]

On Wed, Jul 26, 2017 at 07:05:01PM +0200, Rafael J. Wysocki wrote:
> On Wednesday, July 26, 2017 04:12:59 PM Mika Westerberg wrote:
> > On Wed, Jul 26, 2017 at 02:48:54PM +0200, Rafael J. Wysocki wrote:
> > > On Wednesday, July 26, 2017 11:32:44 AM Mika Westerberg wrote:
> > > > On Tue, Jul 25, 2017 at 06:10:57PM +0200, Rafael J. Wysocki wrote:
> > > > > On Tuesday, July 25, 2017 01:00:12 PM Mika Westerberg wrote:
> > > > > > On Tue, Jul 25, 2017 at 01:31:00AM +0200, Rafael J. Wysocki wrote:
> > > > > > > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > > > > > > 
> > > > > > > On one of my test machines nhi_mailbox_cmd() called from icm_suspend()
> > > > > > > times out and returnes an error which then is propagated to the
> > > > > > > caller and causes the entire system suspend to be aborted which isn't
> > > > > > > very useful.
> > > > > > > 
> > > > > > > Instead of aborting system suspend, print the error into the log
> > > > > > > and continue.
> > > > > > 
> > > > > > I agree, it should not prevent suspend but I wonder why it fails in the
> > > > > > first place? Can you check what is the return value?
> > > > > 
> > > > > As per the above, the error is a timeout, ie. -ETIMEDOUT.
> > > > 
> > > > Ah, right I somehow missed that.
> > > > 
> > > > Does it have Falcon Ridge controller or Alpine Ridge?
> > > 
> > > I'll check later today, but i guess you'll know (see below).
> > 
> > No need to check, it is Alpine Ridge (since it is Dell 9360).
> > 
> > > > Just to make sure, can you increase the timeout in nhi_mailbox_cmd()
> > > > to 1000ms or so. It should not take that long though but better to check.
> > > 
> > > Well, I can do that, but I don't think it will help.
> > > 
> > > It just looks like the chip is not responding at all at that point.
> > 
> > I see.
> > 
> > Then I think we should apply your patch now and we can investigate this
> > further offline and hopefully find the root cause for the problem.
> > 
> > For this patch:
> > 
> > Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> 
> OK
> 
> I guess I can apply it, then, or if anyone else in the CC wants to do that,
> please let me know.

Greg typically takes these but I'm fine either way.

(Eventually we should probably establish Thunderbolt tree/branch in
 kernel.org where we gather all Thunderbolt related patches and just send
 pull request to Greg or something like that).

> > > > Which system this is BTW?
> > > 
> > > It's the Dell 9360. :-)
> > > 
> > > Sometimes after a reboot or a power cycle it starts in a state in which the
> > > TBT controller and a USB one (which seem to be somehow connected)
> > > appear to be dead or at least really flaky.  Basically, the box needs to be
> > > power-cycled again to get rid of this condition and then everything works.
> > 
> > The xHCI controller is part of the Thunderbolt controller so whenever
> > you have normal USB-C device connected there, you should also see the
> > Alpine Ridge hierarchy in lspci output but the Thunderbolt host
> > controller is not there.
> 
> I don't have any USB-C devices, though, so I can't really test it this way ATM.
> 
> It's jjust never used now. :-)

OK. We have one 9365 which I think should be pretty similar. I'll give
it a try once I find it ;-)