On Fri, Jun 11, 2021 at 07:54:07AM +0200, Maxime Ripard wrote: > On Thu, Jun 10, 2021 at 11:00:05PM +0200, Daniel Vetter wrote: > > On Thu, Jun 10, 2021 at 7:47 PM Maxime Ripard <maxime@xxxxxxxxxx> 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 > > > > I'm pretty sure my r-b was without this ... > > Yeah, sorry. I wanted to tell you on IRC that you wanted to have a > second look, but I shouldn't have kept it and caught you by surprise > indeed. > > > Why exactly do we need this? KMS is meant to be fairly generic (bugs > > throw a wrench around here sometimes, and semantics can be tricky). If > > we open up the door to yolo vendor properties in upstream, then that > > goal is pretty much written off. And we've been there with vendor > > properties, it's a giantic mess. > > > > Minimally drop my r-b, I'm definitely not in support of this idea. > > So the argument Lidiu and Laurent made was that in some cases, getting a > generic property right with only a couple of users is hard. So they > advocated for the right to keep non-generic properties. I can get the > argument, and no-one else said that was wrong, so it felt like the > consensus was there. My argument was two-fold. On one hand, there's the issue of standardizing properties when we have a single example. I don't have a good solution for that chicken-and-egg issue, when we tell vendor they should standardize properties, and when they ask how, we tell them we don't know as it hasn't been done before. The option for allowing a staging playground for vendor properties here isn't something I like, but we'll need something similar one way or another. Perhaps at the cost of not guaranteeing userspace ABI for those properties, and converting them later to something standard (it won't be received well by vendor of course, and will make a push for mainline more difficult to sell, so it's not a great solution). On the other hand, there are esoteric vendor-specific features for which standardization really doesn't make sense. For those, I think vendor-specific properties are fine, as long as they're properly documented, with a design documentation merged at the same time as the property. A vendor prefix is really just a namespace clash handling tool here. > > If there's a strong consensus that we really need this then I'm not > > going to nack this, but this really needs a pile of acks from > > compositor folks that they're willing to live with the resulting > > fallout this will likely bring. Your cc list seems to have an absence > > of compositor folks, but instead every driver maintainer. That's > > backwards. We make uapi for userspace, not for kernel driver > > maintainers! > > Right, but it's mostly about in-kernel rules though? And you're the one > who mentionned CC'ing the driver maintainers in the first iteration? > > > ltdr; I'd go back to v2. And then cc compositor folks on this to get > > their ack. > > So, Pekka, Simon, is there anyone else I should Cc? -- Regards, Laurent Pinchart
