From: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
To: Thierry Reding <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Subject: Re: [PATCH 2/2] iommu: Implement a dummy bus_set_iommu()
Date: Wed, 22 Oct 2014 16:29:22 +0200 [thread overview]
Message-ID: <20141022142922.GH10074@8bytes.org> (raw)
In-Reply-To: <20141015091043.GA13162@ulmo>
On Wed, Oct 15, 2014 at 11:10:44AM +0200, Thierry Reding wrote:
> It seems like I never got back to you on this. The reason here is that
> for Tegra the IOMMU is part of a larger IP block. The IP block is
> primarily a memory controller with a bunch of configuration knobs for
> arbitration, prioritization and whatnot. A smaller part of the device
> does the IOMMU translation. Therefore the IOMMU implementation would
> be part of a larger driver, and having this dummy would reduce the
> amount of #ifdefs required.
>
> bus_set_iommu() is also the only function in include/linux/iommu.h that
> doesn't have a dummy, so it seemed like a natural thing to do.
>
> That said, I can work around this being absent for !IOMMU_API.
Or you make this "larger driver" just depend on IOMMU_API? Otherwise you
need the #ifdefs anyway to not carry around the iommu-ops functions in
the driver without having the iommu core enabled, no?
Joerg
next prev parent reply other threads:[~2014-10-22 14:29 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-01 12:45 [PATCH 1/2] iommu: Always define struct iommu_ops Thierry Reding
[not found] ` <1406897113-20099-1-git-send-email-thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2014-08-01 12:45 ` [PATCH 2/2] iommu: Implement a dummy bus_set_iommu() Thierry Reding
[not found] ` <1406897113-20099-2-git-send-email-thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2014-08-18 16:57 ` Joerg Roedel
2014-10-15 9:10 ` Thierry Reding
2014-10-22 14:29 ` Joerg Roedel [this message]
[not found] ` <20141022142922.GH10074-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
2014-10-23 8:09 ` Thierry Reding
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=20141022142922.GH10074@8bytes.org \
--to=joro-zlv9swrftaidnm+yrofe0a@public.gmane.org \
--cc=iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org \
--cc=linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \
--cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
/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).