From: Joerg Roedel <joerg.roedel@amd.com>
To: Ohad Ben-Cohen <ohad@wizery.com>
Cc: <iommu@lists.linux-foundation.org>,
<linux-kernel@vger.kernel.org>,
David Woodhouse <dwmw2@infradead.org>,
David Brown <davidb@codeaurora.org>,
Tony Lindgren <tony@atomide.com>,
Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
Stuart Yoder <b08248@gmail.com>,
Scott Wood <scottwood@freescale.com>,
Hiroshi Doyu <hdoyu@nvidia.com>
Subject: Re: [PATCH 2/6] iommu/amd: Implement DOMAIN_ATTR_GEOMETRY attribute
Date: Fri, 27 Jan 2012 14:03:29 +0100 [thread overview]
Message-ID: <20120127130329.GM19255@amd.com> (raw)
In-Reply-To: <CAK=WgbZQB+76FuJXK82x09CieDmF23zLQ8KbHbEtjnQsc_4axg@mail.gmail.com>
On Fri, Jan 27, 2012 at 01:00:02PM +0200, Ohad Ben-Cohen wrote:
> On Fri, Jan 27, 2012 at 12:26 PM, Joerg Roedel <joerg.roedel@amd.com> wrote:
> > But probably we can replace the 'void *data' with a 'union
> > domain_attr'? This will give us some type-safety.
>
> I was thinking that since the geometry concept is actually handled by
> the core itself, it could probably have its own dedicated function.
Note that only the read-side is handled by the core. An IOMMU driver may
decide to implement a write-side for the geometry which would be not in
the core then. Having a dedicated function for the write-side does not
make sense because (for now) there is only one upcoming driver requiring
this. So we either end up with an asymetric interface for read and write
or with an api function implemented by only one driver.
I think dedicated functions also make the API harder to use because a
developer first needs to find out if a property is read/written by a
dedicated function or the set/get-attr interface.
The next attribute I have in mind btw. is the default-domain attribute
which can be used set by the core to tell the iommu driver that dma-api
specific optimizations can be applied to this domain.
Joerg
--
AMD Operating System Research Center
Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach
General Managers: Alberto Bozzo
Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632
next prev parent reply other threads:[~2012-01-27 13:03 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-26 18:40 [PATCH 0/6 v2] IOMMU: Make IOMMU-API ready for GART-like hardware Joerg Roedel
2012-01-26 18:40 ` [PATCH 1/6] iommu: Add domain-attribute handlers Joerg Roedel
2012-01-26 18:40 ` [PATCH 2/6] iommu/amd: Implement DOMAIN_ATTR_GEOMETRY attribute Joerg Roedel
2012-01-27 7:08 ` Ohad Ben-Cohen
2012-01-27 10:26 ` Joerg Roedel
2012-01-27 11:00 ` Ohad Ben-Cohen
2012-01-27 13:03 ` Joerg Roedel [this message]
2012-01-28 20:44 ` Ohad Ben-Cohen
2012-01-30 14:49 ` Joerg Roedel
2012-01-30 15:42 ` Ohad Ben-Cohen
2012-01-26 18:40 ` [PATCH 3/6] iommu/vt-d: " Joerg Roedel
2012-01-26 18:40 ` [PATCH 4/6] iommu/omap: " Joerg Roedel
2012-01-26 18:40 ` [PATCH 5/6] iommu/msm: " Joerg Roedel
2012-01-27 0:07 ` David Brown
2012-01-26 18:40 ` [PATCH 6/6] iommu/tegra: " Joerg Roedel
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=20120127130329.GM19255@amd.com \
--to=joerg.roedel@amd.com \
--cc=b08248@gmail.com \
--cc=davidb@codeaurora.org \
--cc=dwmw2@infradead.org \
--cc=hdoyu@nvidia.com \
--cc=iommu@lists.linux-foundation.org \
--cc=laurent.pinchart@ideasonboard.com \
--cc=linux-kernel@vger.kernel.org \
--cc=ohad@wizery.com \
--cc=scottwood@freescale.com \
--cc=tony@atomide.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;
as well as URLs for NNTP newsgroup(s).