From: Matthew Wilcox <matthew@wil.cx>
To: John Partridge <johnip@sgi.com>
Cc: Roland Dreier <rdreier@cisco.com>,
"Richard B. Johnson" <jmodem@AbominableFirebug.com>,
"Michael S. Tsirkin" <mst@mellanox.co.il>,
linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org,
jeff@garzik.org, openib-general@openib.org,
linux-pci@atrey.karlin.mff.cuni.cz,
David Miller <davem@davemloft.net>
Subject: Re: Ordering between PCI config space writes and MMIO reads?
Date: Wed, 1 Nov 2006 10:14:44 -0700 [thread overview]
Message-ID: <20061101171443.GI11399@parisc-linux.org> (raw)
In-Reply-To: <4548D478.2080704@sgi.com>
On Wed, Nov 01, 2006 at 11:08:08AM -0600, John Partridge wrote:
> So, if I understand correctly, you are saying because we cannot guarantee
> the "flush" a config write even by doing a config read of the same register
> (because the PPB can re-order) we have to make sure we block or spin on the
> config write completion at the lowest level of the config write ?
That's correct. And I'm also saying that the reason this hasn't
been thought about before is that other root bridges have a mechanism
(implicit on x86, explicit on parisc) for waiting for the config write
completion to come back.
Seems to me that Altix uses the SAL calls to access PCI config space
these days, so you can hide it in your firmware rather than patching
Linux.
next prev parent reply other threads:[~2006-11-01 17:14 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-10-24 19:13 Ordering between PCI config space writes and MMIO reads? Roland Dreier
2006-10-24 19:22 ` Jeff Garzik
2006-10-24 21:47 ` Matthew Wilcox
2006-10-24 21:51 ` Roland Dreier
2006-10-24 22:12 ` John Partridge
2006-10-24 22:36 ` Matthew Wilcox
2006-10-24 22:43 ` David Miller
2006-10-25 14:15 ` Roland Dreier
2006-10-31 19:02 ` Roland Dreier
2006-10-31 19:53 ` Michael S. Tsirkin
2006-10-31 19:53 ` Roland Dreier
2006-10-31 19:58 ` Matthew Wilcox
2006-10-31 20:28 ` Michael S. Tsirkin
2006-10-31 20:34 ` Richard B. Johnson
2006-10-31 20:47 ` Matthew Wilcox
2006-10-31 22:30 ` Roland Dreier
2006-11-01 16:27 ` John Partridge
2006-11-01 16:46 ` Matthew Wilcox
2006-11-01 17:08 ` John Partridge
2006-11-01 17:14 ` Matthew Wilcox [this message]
2006-11-01 23:04 ` David Miller
2006-11-02 1:08 ` John Partridge
2006-10-31 20:50 ` Michael S. Tsirkin
2006-10-24 22:59 ` [openib-general] " Jason Gunthorpe
2006-10-25 14:04 ` Roland Dreier
2006-10-24 23:09 ` Michael S. Tsirkin
2006-10-24 23:27 ` Jack Steiner
2006-10-25 14:05 ` Roland Dreier
2006-11-02 3:05 ` Jeremy Higdon
2006-10-24 21:01 ` [openib-general] " JWM
2006-10-24 21:24 ` Alan Cox
2006-10-24 21:29 ` Roland Dreier
2006-10-24 21:37 ` Jeff Garzik
2006-10-25 6:30 ` Grant Grundler
2006-10-25 14:11 ` Roland Dreier
2006-10-25 14:18 ` Matthew Wilcox
2006-10-25 17:15 ` [openib-general] " Jason Gunthorpe
2006-10-25 18:22 ` Michael S. Tsirkin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20061101171443.GI11399@parisc-linux.org \
--to=matthew@wil.cx \
--cc=davem@davemloft.net \
--cc=jeff@garzik.org \
--cc=jmodem@AbominableFirebug.com \
--cc=johnip@sgi.com \
--cc=linux-ia64@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@atrey.karlin.mff.cuni.cz \
--cc=mst@mellanox.co.il \
--cc=openib-general@openib.org \
--cc=rdreier@cisco.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox