From: Yong Wu <yong.wu@mediatek.com>
To: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>,
Matthias Brugger <matthias.bgg@gmail.com>,
Joerg Roedel <joro@8bytes.org>, Rob Herring <robh+dt@kernel.org>,
Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
David Airlie <airlied@linux.ie>,
"Mauro Carvalho Chehab" <mchehab@kernel.org>
Cc: Evan Green <evgreen@chromium.org>,
Robin Murphy <robin.murphy@arm.com>,
Tomasz Figa <tfiga@chromium.org>,
Will Deacon <will.deacon@arm.com>,
<linux-mediatek@lists.infradead.org>,
<srv_heupstream@mediatek.com>, <devicetree@vger.kernel.org>,
<linux-kernel@vger.kernel.org>,
<linux-arm-kernel@lists.infradead.org>,
<iommu@lists.linux-foundation.org>, <youlin.pei@mediatek.com>,
Matthias Kaehlcke <mka@chromium.org>, <anan.sun@mediatek.com>,
<yi.kuo@mediatek.com>, <acourbot@chromium.org>,
<linux-media@vger.kernel.org>, <dri-devel@lists.freedesktop.org>,
"Daniel Vetter" <daniel@ffwll.ch>,
Chun-Kuang Hu <chunkuang.hu@kernel.org>,
"Philipp Zabel" <p.zabel@pengutronix.de>,
Tiffany Lin <tiffany.lin@mediatek.com>,
Hsin-Yi Wang <hsinyi@chromium.org>,
Eizan Miyamoto <eizan@chromium.org>, <anthony.huang@mediatek.com>,
Frank Wunderlich <frank-w@public-files.de>
Subject: Re: [PATCH v8 04/12] iommu/mediatek: Add device_link between the consumer and the larb devices
Date: Sat, 16 Oct 2021 10:23:27 +0800 [thread overview]
Message-ID: <e4c98036dd73b91b8352a162f80240171e2b3f0f.camel@mediatek.com> (raw)
In-Reply-To: <e00b92db-0562-27ca-2f96-1f03ff824988@collabora.com>
On Mon, 2021-10-11 at 14:36 +0200, Dafna Hirschfeld wrote:
>
> On 29.09.21 03:37, Yong Wu wrote:
> > MediaTek IOMMU-SMI diagram is like below. all the consumer connect
> > with
> > smi-larb, then connect with smi-common.
> >
> > M4U
> > |
> > smi-common
> > |
> > -------------
> > | | ...
> > | |
> > larb1 larb2
> > | |
> > vdec venc
> >
> > When the consumer works, it should enable the smi-larb's power
> > which
> > also need enable the smi-common's power firstly.
> >
> > Thus, First of all, use the device link connect the consumer and
> > the
> > smi-larbs. then add device link between the smi-larb and smi-
> > common.
> >
> > This patch adds device_link between the consumer and the larbs.
> >
> > When device_link_add, I add the flag DL_FLAG_STATELESS to avoid
> > calling
> > pm_runtime_xx to keep the original status of clocks. It can avoid
> > two
> > issues:
> > 1) Display HW show fastlogo abnormally reported in [1]. At the
> > beggining,
> > all the clocks are enabled before entering kernel, but the clocks
> > for
> > display HW(always in larb0) will be gated after clk_enable and
> > clk_disable
> > called from device_link_add(->pm_runtime_resume) and rpm_idle. The
> > clock
> > operation happened before display driver probe. At that time, the
> > display
> > HW will be abnormal.
> >
> > 2) A deadlock issue reported in [2]. Use DL_FLAG_STATELESS to skip
> > pm_runtime_xx to avoid the deadlock.
> >
> > Corresponding, DL_FLAG_AUTOREMOVE_CONSUMER can't be added, then
> > device_link_removed should be added explicitly.
> >
> > [1]
> > https://lore.kernel.org/linux-mediatek/1564213888.22908.4.camel@mhfsdcap03/
> > [2] https://lore.kernel.org/patchwork/patch/1086569/
> >
> > Suggested-by: Tomasz Figa <tfiga@chromium.org>
> > Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> > Tested-by: Frank Wunderlich <frank-w@public-files.de> # BPI-
> > R2/MT7623
> > ---
> > drivers/iommu/mtk_iommu.c | 22 ++++++++++++++++++++++
> > drivers/iommu/mtk_iommu_v1.c | 20 +++++++++++++++++++-
> > 2 files changed, 41 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> > index d5848f78a677..a2fa55899434 100644
> > --- a/drivers/iommu/mtk_iommu.c
> > +++ b/drivers/iommu/mtk_iommu.c
> > @@ -560,22 +560,44 @@ static struct iommu_device
> > *mtk_iommu_probe_device(struct device *dev)
> > {
> > struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> > struct mtk_iommu_data *data;
> > + struct device_link *link;
> > + struct device *larbdev;
> > + unsigned int larbid;
> >
> > if (!fwspec || fwspec->ops != &mtk_iommu_ops)
> > return ERR_PTR(-ENODEV); /* Not a iommu client device
> > */
> >
> > data = dev_iommu_priv_get(dev);
> >
> > + /*
> > + * Link the consumer device with the smi-larb device(supplier)
> > + * The device in each a larb is a independent HW. thus only
> > link
> > + * one larb here.
> > + */
> > + larbid = MTK_M4U_TO_LARB(fwspec->ids[0]);
>
> so larbid is always the same for all the ids of a device?
Yes. For me, each a dtsi node should represent a HW unit which can only
connect one larb.
> If so maybe it worth testing it and return error if this is not the
> case.
Thanks for the suggestion. This is very helpful. I did see someone put
the different larbs in one node. I will check this, and add return
EINVAL for this case.
>
> Thanks,
> Dafna
> >
_______________________________________________
Linux-mediatek mailing list
Linux-mediatek@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-mediatek
next prev parent reply other threads:[~2021-10-16 2:24 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-29 1:37 [PATCH v8 00/12] Clean up "mediatek,larb" Yong Wu
2021-09-29 1:37 ` [PATCH v8 01/12] dt-binding: mediatek: Get rid of mediatek, larb for multimedia HW Yong Wu
2021-09-29 1:37 ` [PATCH v8 02/12] iommu/mediatek-v1: Free the existed fwspec if the master dev already has Yong Wu
2021-09-29 1:37 ` [PATCH v8 03/12] iommu/mediatek: Add probe_defer for smi-larb Yong Wu
2021-09-29 16:33 ` Dafna Hirschfeld
2021-09-30 7:14 ` Yong Wu
2021-09-29 1:37 ` [PATCH v8 04/12] iommu/mediatek: Add device_link between the consumer and the larb devices Yong Wu
2021-10-11 12:36 ` Dafna Hirschfeld
2021-10-16 2:23 ` Yong Wu [this message]
2021-10-18 7:13 ` Dafna Hirschfeld
2021-10-25 3:57 ` Yong Wu
2021-09-29 1:37 ` [PATCH v8 05/12] media: mtk-jpeg: Get rid of mtk_smi_larb_get/put Yong Wu
2021-09-29 1:37 ` [PATCH v8 06/12] media: mtk-mdp: " Yong Wu
2021-09-29 1:37 ` [PATCH v8 07/12] drm/mediatek: Add pm runtime support for ovl and rdma Yong Wu
2021-09-29 1:37 ` [PATCH v8 08/12] drm/mediatek: Get rid of mtk_smi_larb_get/put Yong Wu
2021-09-29 1:37 ` [PATCH v8 09/12] media: mtk-vcodec: " Yong Wu
2021-09-29 12:13 ` Dafna Hirschfeld
2021-09-30 3:28 ` Yong Wu
2021-09-30 10:57 ` Dafna Hirschfeld
2021-10-07 2:57 ` Yong Wu
2021-09-29 1:37 ` [PATCH v8 10/12] memory: mtk-smi: " Yong Wu
2021-09-29 1:37 ` [PATCH v8 11/12] arm: dts: mediatek: Get rid of mediatek, larb for MM nodes Yong Wu
2021-09-29 1:37 ` [PATCH v8 12/12] arm64: " Yong Wu
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=e4c98036dd73b91b8352a162f80240171e2b3f0f.camel@mediatek.com \
--to=yong.wu@mediatek.com \
--cc=acourbot@chromium.org \
--cc=airlied@linux.ie \
--cc=anan.sun@mediatek.com \
--cc=anthony.huang@mediatek.com \
--cc=chunkuang.hu@kernel.org \
--cc=dafna.hirschfeld@collabora.com \
--cc=daniel@ffwll.ch \
--cc=devicetree@vger.kernel.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=eizan@chromium.org \
--cc=evgreen@chromium.org \
--cc=frank-w@public-files.de \
--cc=hsinyi@chromium.org \
--cc=iommu@lists.linux-foundation.org \
--cc=joro@8bytes.org \
--cc=krzysztof.kozlowski@canonical.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=matthias.bgg@gmail.com \
--cc=mchehab@kernel.org \
--cc=mka@chromium.org \
--cc=p.zabel@pengutronix.de \
--cc=robh+dt@kernel.org \
--cc=robin.murphy@arm.com \
--cc=srv_heupstream@mediatek.com \
--cc=tfiga@chromium.org \
--cc=tiffany.lin@mediatek.com \
--cc=will.deacon@arm.com \
--cc=yi.kuo@mediatek.com \
--cc=youlin.pei@mediatek.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).