linux-kernel - Re: [PATCH v9 5/9] media: platform: Add Cedrus VPU decoder driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180907132620.lmsvlwpa3rzioj2h@flea>
Date:   Fri, 7 Sep 2018 15:26:20 +0200
From:   Maxime Ripard <maxime.ripard@...tlin.com>
To:     Hans Verkuil <hverkuil@...all.nl>
Cc:     Paul Kocialkowski <contact@...lk.fr>, linux-media@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, devel@...verdev.osuosl.org,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Chen-Yu Tsai <wens@...e.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Paul Kocialkowski <paul.kocialkowski@...tlin.com>,
        Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
        linux-sunxi@...glegroups.com, Randy Li <ayaka@...lik.info>,
        Ezequiel Garcia <ezequiel@...labora.com>,
        Tomasz Figa <tfiga@...omium.org>,
        Alexandre Courbot <acourbot@...omium.org>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        Sakari Ailus <sakari.ailus@...ux.intel.com>
Subject: Re: [PATCH v9 5/9] media: platform: Add Cedrus VPU decoder driver

Hi Hans,

On Fri, Sep 07, 2018 at 03:13:19PM +0200, Hans Verkuil wrote:
> On 09/07/2018 12:24 AM, Paul Kocialkowski wrote:
> > From: Paul Kocialkowski <paul.kocialkowski@...tlin.com>
> > 
> > This introduces the Cedrus VPU driver that supports the VPU found in
> > Allwinner SoCs, also known as Video Engine. It is implemented through
> > a V4L2 M2M decoder device and a media device (used for media requests).
> > So far, it only supports MPEG-2 decoding.
> > 
> > Since this VPU is stateless, synchronization with media requests is
> > required in order to ensure consistency between frame headers that
> > contain metadata about the frame to process and the raw slice data that
> > is used to generate the frame.
> > 
> > This driver was made possible thanks to the long-standing effort
> > carried out by the linux-sunxi community in the interest of reverse
> > engineering, documenting and implementing support for the Allwinner VPU.
> > 
> > Signed-off-by: Paul Kocialkowski <paul.kocialkowski@...tlin.com>
> > Acked-by: Maxime Ripard <maxime.ripard@...tlin.com>
> 
> One high-level comment:
> 
> Can you add a TODO file for this staging driver? This can be done in
> a follow-up patch.
> 
> It should contain what needs to be done to get this out of staging:
> 
> - Request API needs to stabilize
> - Userspace support for stateless codecs must be created

On that particular note, as part of the effort to develop the driver,
we've also developped two userspace components:

  - v4l2-request-test, that has a bunch of sample frames for various
    codecs and will rely solely on the kernel request api (and DRM for
    the display part) to test and bringup a particular driver
    https://github.com/bootlin/v4l2-request-test

  - libva-v4l2-request, that is a libva implementation using the
    request API
    https://github.com/bootlin/libva-v4l2-request

Did you have something else in mind?

Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)