Re: [PATCH 1/3] PCI: Rework default handling of suspend and resume

From: Linus Torvalds
Date: Sat Dec 06 2008 - 13:01:30 EST




On Sat, 6 Dec 2008, Rafael J. Wysocki wrote:
>
> So, to fix the issue at hand, I'd like the $subject patch to go first. Then,
> there is a major update of the new framework waiting for .29 in the Greg's
> tree (that's the main reason why nobody uses it so far, BTW) and I'd really
> prefer it to go next. After it's been merged, I'm going to add the mandatory
> suspend-resume things (save state and go to a low power state on suspend,
> restore state on resume) to the new framework in a separete patch.
>
> Is this plan acceptable?

Sounds good to me. And assuming Jesse/Greg are all aboard, I'll just wait
for the pull requests from Jesse and Greg.

The only thing I'll do right now is to send off my "print out ICH6+
LPC resources" patch again to Jesse, with a changelog etc. It can probably
go in as-is (it really just adds printk's), but since it didn't matter
anyway we migth as well just do it as a PCI thing for 2.6.29 too.

On a similar note, I wonder what we should do about the whole "transparent
bridge resource allocation" thing. It also didn't end up really mattering,
even if it apparently made a difference for Frans. The question is just
whether we would be better off with IO windows for transparent buses (the
way we try to set things up now), or with a simpler PCI resource tree that
just takes advantage of the transparency.

The bridge windows _may_ result in better PCI throughput behind such a
bridge, so there is some argument for keeping them. On the other hand,
transparent bridges aren't generally for high-performance stuff anyway,
and one advantage of the transparency is the flexibility it allows (ie we
don't _need_ to set up the static bridging windows).

I dunno. I wonder what Windows does. Following Windows in areas like this
tends to have the advantage that it's what the firmware and the hardware
has generally been tested with most. At the same time, I'm not sure this
is necessarily a very bug-prone area for either firmware or hardware. If
there's actual bridge bugs wrt the windows, I suspect such a bridge would
be broken enough to be unusable regardless.

Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/