From: "Jernej Škrabec" <jernej.skrabec@gmail.com>
To: Maxime Ripard <maxime@cerno.tech>
Cc: Mark Rutland <mark.rutland@arm.com>,
devicetree@vger.kernel.org, Joerg Roedel <joro@8bytes.org>,
iommu@lists.linux-foundation.org, Chen-Yu Tsai <wens@csie.org>,
Rob Herring <robh+dt@kernel.org>,
Frank Rowand <frowand.list@gmail.com>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 3/3] arm64: dts: allwinner: h6: Add IOMMU
Date: Mon, 27 Jan 2020 20:04:02 +0100 [thread overview]
Message-ID: <2140600.ElGaqSPkdT@jernej-laptop> (raw)
In-Reply-To: <20200127142339.crxsuunzec5drfe2@gilmour.lan>
Hi!
Dne ponedeljek, 27. januar 2020 ob 15:23:39 CET je Maxime Ripard napisal(a):
> Hi Jernej,
>
> On Fri, Jan 24, 2020 at 09:54:23PM +0100, Jernej Škrabec wrote:
> > Dne sreda, 22. januar 2020 ob 13:44:09 CET je Maxime Ripard napisal(a):
> > > Now that we have a driver for the IOMMU, let's start using it.
> > >
> > > Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> > > ---
> > >
> > > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 11 +++++++++++
> > > 1 file changed, 11 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi index
> > > 29824081b43b..8608bcf1c52c 100644
> > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > @@ -53,6 +53,7 @@
> > >
> > > de: display-engine {
> > >
> > > compatible = "allwinner,sun50i-h6-display-engine";
> > > allwinner,pipelines = <&mixer0>;
> > >
> > > + iommus = <&iommu 0>;
> > >
> > > status = "disabled";
> > >
> > > };
> >
> > Isn't iommu property of the mixer node? After all, mixer is the one which
> > reads one or more framebuffers. Once second mixer is defined, would you
> > put
> > another iommu phandle here?
>
> You're right. I added it during the early dev, and forgot to remove
> it. Thanks!
Remove it or move it? I guess enabling iommu support in each driver needs a
bit more work than just referencing iommu node, right? At least in such case
buffers don't need to be allocated by CMA, which sun4i-drm driver currently
use.
I just take another look at BSP kernel and it seems that only one channel is
used for whole display stack. That would mean that both mixers would have same
iommu phandle, right? Confusingly enough, DE2 iommu channel seems to be for
deinterlace core.
Best regards,
Jernej
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-01-27 19:04 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-22 12:44 [PATCH 0/3] iommu: Add Allwinner H6 IOMMU driver Maxime Ripard
2020-01-22 12:44 ` [PATCH 1/3] dt-bindings: iommu: Add Allwinner H6 IOMMU bindings Maxime Ripard
2020-01-23 14:44 ` Rob Herring
2020-01-22 12:44 ` [PATCH 2/3] iommu: Add Allwinner H6 IOMMU driver Maxime Ripard
2020-01-23 18:47 ` Robin Murphy
2020-01-27 14:22 ` Maxime Ripard
2020-01-27 19:01 ` Robin Murphy
2020-02-11 12:39 ` Maxime Ripard
2020-01-22 12:44 ` [PATCH 3/3] arm64: dts: allwinner: h6: Add IOMMU Maxime Ripard
2020-01-24 20:54 ` Jernej Škrabec
2020-01-27 14:23 ` Maxime Ripard
2020-01-27 19:04 ` Jernej Škrabec [this message]
2020-01-28 14:41 ` Robin Murphy
2020-01-29 17:27 ` Maxime Ripard
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=2140600.ElGaqSPkdT@jernej-laptop \
--to=jernej.skrabec@gmail.com \
--cc=devicetree@vger.kernel.org \
--cc=frowand.list@gmail.com \
--cc=iommu@lists.linux-foundation.org \
--cc=joro@8bytes.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=mark.rutland@arm.com \
--cc=maxime@cerno.tech \
--cc=robh+dt@kernel.org \
--cc=wens@csie.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).