Hi Maxime,
On Thu, Jun 10, 2021 at 07:47:31PM +0200, Maxime Ripard wrote:
> New KMS properties come with a bunch of requirements to avoid each
> driver from running their own, inconsistent, set of properties,
> eventually leading to issues like property conflicts, inconsistencies
> between drivers and semantics, etc.
>
> Let's document what we expect.
>
> Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> Cc: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx>
> Cc: Alex Deucher <alexander.deucher@xxxxxxx>
> Cc: Alison Wang <alison.wang@xxxxxxx>
> Cc: Alyssa Rosenzweig <alyssa.rosenzweig@xxxxxxxxxxxxx>
> Cc: Andrew Jeffery <andrew@xxxxxxxx>
> Cc: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
> Cc: Anitha Chrisanthus <anitha.chrisanthus@xxxxxxxxx>
> Cc: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
> Cc: Ben Skeggs <bskeggs@xxxxxxxxxx>
> Cc: Boris Brezillon <bbrezillon@xxxxxxxxxx>
> Cc: Brian Starkey <brian.starkey@xxxxxxx>
> Cc: Chen Feng <puck.chen@xxxxxxxxxxxxx>
> Cc: Chen-Yu Tsai <wens@xxxxxxxx>
> Cc: Christian Gmeiner <christian.gmeiner@xxxxxxxxx>
> Cc: "Christian König" <christian.koenig@xxxxxxx>
> Cc: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
> Cc: Edmund Dea <edmund.j.dea@xxxxxxxxx>
> Cc: Eric Anholt <eric@xxxxxxxxxx>
> Cc: Fabio Estevam <festevam@xxxxxxxxx>
> Cc: Gerd Hoffmann <kraxel@xxxxxxxxxx>
> Cc: Haneen Mohammed <hamohammed.sa@xxxxxxxxx>
> Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
> Cc: "Heiko Stübner" <heiko@xxxxxxxxx>
> Cc: Huang Rui <ray.huang@xxxxxxx>
> Cc: Hyun Kwon <hyun.kwon@xxxxxxxxxx>
> Cc: Inki Dae <inki.dae@xxxxxxxxxxx>
> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
> Cc: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> Cc: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
> Cc: Joel Stanley <joel@xxxxxxxxx>
> Cc: John Stultz <john.stultz@xxxxxxxxxx>
> Cc: Jonas Karlman <jonas@xxxxxxxxx>
> Cc: Jonathan Hunter <jonathanh@xxxxxxxxxx>
> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
> Cc: Joonyoung Shim <jy0922.shim@xxxxxxxxxxx>
> Cc: Jyri Sarha <jyri.sarha@xxxxxx>
> Cc: Kevin Hilman <khilman@xxxxxxxxxxxx>
> Cc: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
> Cc: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
> Cc: Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx>
> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
> Cc: Liviu Dudau <liviu.dudau@xxxxxxx>
> Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> Cc: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>
> Cc: Marek Vasut <marex@xxxxxxx>
> Cc: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
> Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx>
> Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx>
> Cc: Maxime Ripard <mripard@xxxxxxxxxx>
> Cc: Melissa Wen <melissa.srw@xxxxxxxxx>
> Cc: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> Cc: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
> Cc: "Noralf Trønnes" <noralf@xxxxxxxxxxx>
> Cc: NXP Linux Team <linux-imx@xxxxxxx>
> Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
> Cc: Patrik Jakobsson <patrik.r.jakobsson@xxxxxxxxx>
> Cc: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> Cc: Philippe Cornu <philippe.cornu@xxxxxxxxxxx>
> Cc: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
> Cc: Qiang Yu <yuq825@xxxxxxxxx>
> Cc: Rob Clark <robdclark@xxxxxxxxx>
> Cc: Robert Foss <robert.foss@xxxxxxxxxx>
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Cc: Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx>
> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
> Cc: Roland Scheidegger <sroland@xxxxxxxxxx>
> Cc: Russell King <linux@xxxxxxxxxxxxxxx>
> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Cc: Sandy Huang <hjc@xxxxxxxxxxxxxx>
> Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> Cc: Sean Paul <sean@xxxxxxxxxx>
> Cc: Seung-Woo Kim <sw0312.kim@xxxxxxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> Cc: Stefan Agner <stefan@xxxxxxxx>
> Cc: Steven Price <steven.price@xxxxxxx>
> Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
> Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
> Cc: Tian Tao <tiantao6@xxxxxxxxxxxxx>
> Cc: Tomeu Vizoso <tomeu.vizoso@xxxxxxxxxxxxx>
> Cc: Tomi Valkeinen <tomba@xxxxxxxxxx>
> Cc: VMware Graphics <linux-graphics-maintainer@xxxxxxxxxx>
> Cc: Xinliang Liu <xinliang.liu@xxxxxxxxxx>
> Cc: Xinwei Kong <kong.kongxinwei@xxxxxxxxxxxxx>
> Cc: Yannick Fertre <yannick.fertre@xxxxxxxxxxx>
> Cc: Zack Rusin <zackr@xxxxxxxxxx>
> Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
>
> ---
>
> Changes from v2:
> - Take into account the feedback from Laurent and Lidiu to no longer
> force generic properties, but prefix vendor-specific properties with
> the vendor name
>
> Changes from v1:
> - Typos and wording reported by Daniel and Alex
> ---
> Documentation/gpu/drm-kms.rst | 27 +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst
> index 87e5023e3f55..bbe254dca635 100644
> --- a/Documentation/gpu/drm-kms.rst
> +++ b/Documentation/gpu/drm-kms.rst
> @@ -463,6 +463,33 @@ KMS Properties
> This section of the documentation is primarily aimed at user-space developers.
> For the driver APIs, see the other sections.
>
> +Requirements
> +------------
> +
> +KMS drivers might need to add extra properties to support new features.
> +Each new property introduced in a driver need to meet a few
> +requirements, in addition to the one mentioned above.:
> +
> +- Before the introduction of any vendor-specific properties, they must
> + be first checked against the generic ones to avoid any conflict or
> + redundancy.
> +
> +- Vendor-specific properties must be prefixed by the vendor's name,
> + following the syntax "$vendor:$property".
> +
> +- Generic properties must be standardized, with some documentation to
> + describe how the property can be used.
> +
> +- Generic properties must provide a generic helper in the core code to
> + register that property on the object it attaches to.
> +
> +- Generic properties content must be decoded by the core and provided in
> + the object's associated state structure. That includes anything
> + drivers might want to precompute, like :c:type:`struct drm_clip_rect
> + <drm_clip_rect>` for planes.
> +
> +- An IGT test should be submitted.
> +
> Property Types and Blob Property Support
> ----------------------------------------
Looks nice, thanks for the work!
Reviewed-by: Liviu Dudau <liviu.dudau@xxxxxxx>
Best regards,
Liviu
>
> --
> 2.31.1
>
--
====================
| I would like to |
| fix the world, |
| but they're not |
| giving me the |
\ source code! /
---------------
¯\_(ツ)_/¯
