public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alex Williamson <alex.williamson@redhat.com>
Cc: David Gibson <dwg@au1.ibm.com>,
	joerg.roedel@amd.com, dwmw2@infradead.org,
	iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
	chrisw@redhat.com, agraf@suse.de, scottwood@freescale.com,
	B08248@freescale.com
Subject: Re: [PATCH 1/4] iommu: Add iommu_device_group callback and iommu_group sysfs entry
Date: Fri, 02 Dec 2011 08:32:31 +1100	[thread overview]
Message-ID: <1322775151.3729.25.camel@pasglop> (raw)
In-Reply-To: <1322722110.26545.68.camel@bling.home>

On Wed, 2011-11-30 at 23:48 -0700, Alex Williamson wrote:

> See bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops).  It
> wasn't long ago that we had a global iommu_ops.

Right now, the dma_ops are per-device but the iommu populate/depopulate
hooks are system global, installed by the platform code at boot time, on
powerpc. We could try to "fit in" an iommu "driver" at that point.

In theory, you can connect separate IO chips on POWER server and in fact
it happens on high end boxes, tho they tend to have a similar "PE#"
mechanism, but with different constraints and resources capacities.
However we aren't concerned with that initially for KVM as we are
targetting only lower end machines with only one p7ioc for now.

But I can see more heterogenous setup showing up in embedded space..
 
> Are heterogeneous
> iommus using different drivers on the same bus_type really a possibility
> on your system, or are we dealing with hypothetical situations?  You'd
> currently need to multiplex iommu_ops callbacks between the drivers
> yourself.

We could.

Ben.



  parent reply	other threads:[~2011-12-01 21:33 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-21 19:55 [PATCH 0/4] iommu: iommu_ops group interface Alex Williamson
2011-10-21 19:56 ` [PATCH 1/4] iommu: Add iommu_device_group callback and iommu_group sysfs entry Alex Williamson
2011-11-30  2:42   ` David Gibson
2011-11-30  4:51     ` Benjamin Herrenschmidt
2011-11-30  5:25       ` Alex Williamson
2011-11-30  9:23         ` Benjamin Herrenschmidt
2011-12-01  0:06           ` David Gibson
2011-12-01  6:20           ` Alex Williamson
2011-12-01  0:03         ` David Gibson
2011-12-01  0:52           ` Chris Wright
2011-12-01  0:57             ` David Gibson
2011-12-01  1:04               ` Chris Wright
2011-12-01  1:50                 ` Benjamin Herrenschmidt
2011-12-01  2:00                   ` David Gibson
2011-12-01  2:05                   ` Chris Wright
2011-12-01  7:28                     ` Alex Williamson
2011-12-01 14:02                     ` Yoder Stuart-B08248
2011-12-01  6:48           ` Alex Williamson
2011-12-01 10:33             ` David Woodhouse
2011-12-01 14:34               ` Alex Williamson
2011-12-01 21:46                 ` Benjamin Herrenschmidt
2011-12-01 22:37                   ` Alex Williamson
2011-12-01 23:14                 ` David Woodhouse
2011-12-07  6:20                   ` Benjamin Herrenschmidt
2011-12-01 21:32             ` Benjamin Herrenschmidt [this message]
2011-10-21 19:56 ` [PATCH 2/4] intel-iommu: Implement iommu_device_group Alex Williamson
2011-11-08 17:23   ` Roedel, Joerg
2011-11-10 15:22     ` David Woodhouse
2011-10-21 19:56 ` [PATCH 3/4] amd-iommu: " Alex Williamson
2011-10-21 19:56 ` [PATCH 4/4] iommu: Add option to group multi-function devices Alex Williamson
2011-12-01  0:11   ` David Gibson
2011-10-21 20:34 ` [PATCH 0/4] iommu: iommu_ops group interface Woodhouse, David
2011-10-21 21:16   ` Alex Williamson
2011-10-21 22:39     ` Woodhouse, David
2011-10-21 22:34   ` Alex Williamson
2011-10-27 16:31 ` Alex Williamson
2011-11-15 15:51 ` Roedel, Joerg

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=1322775151.3729.25.camel@pasglop \
    --to=benh@kernel.crashing.org \
    --cc=B08248@freescale.com \
    --cc=agraf@suse.de \
    --cc=alex.williamson@redhat.com \
    --cc=chrisw@redhat.com \
    --cc=dwg@au1.ibm.com \
    --cc=dwmw2@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=joerg.roedel@amd.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=scottwood@freescale.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