Hi, On Thu, Sep 22, 2022 at 04:25:17PM +0200, Maxime Ripard wrote: > Here's a series aiming at improving the command line named modes support, > and more importantly how we deal with all the analog TV variants. > > The named modes support were initially introduced to allow to specify the > analog TV mode to be used. > > However, this was causing multiple issues: > > * The mode name parsed on the command line was passed directly to the > driver, which had to figure out which mode it was suppose to match; > > * Figuring that out wasn't really easy, since the video= argument or what > the userspace might not even have a name in the first place, but > instead could have passed a mode with the same timings; > > * The fallback to matching on the timings was mostly working as long as > we were supporting one 525 lines (most likely NSTC) and one 625 lines > (PAL), but couldn't differentiate between two modes with the same > timings (NTSC vs PAL-M vs NSTC-J for example); > > * There was also some overlap with the tv mode property registered by > drm_mode_create_tv_properties(), but named modes weren't interacting > with that property at all. > > * Even though that property was generic, its possible values were > specific to each drivers, which made some generic support difficult. > > Thus, I chose to tackle in multiple steps: > > * A new TV mode property was introduced, with generic values, each driver > reporting through a bitmask what standard it supports to the userspace; > > * This option was added to the command line parsing code to be able to > specify it on the kernel command line, and new atomic_check and reset > helpers were created to integrate properly into atomic KMS; > > * The named mode parsing code is now creating a proper display mode for > the given named mode, and the TV standard will thus be part of the > connector state; > > * Two drivers were converted and tested for now (vc4 and sun4i), with > some backward compatibility code to translate the old TV mode to the > new TV mode; > > Unit tests were created along the way. > > One can switch from NTSC to PAL now using (on vc4) > > modetest -M vc4 -s 53:720x480i -w 53:'TV mode':1 # NTSC > modetest -M vc4 -s 53:720x576i -w 53:'TV mode':4 # PAL > > Let me know what you think, > Maxime > > To: David Airlie > To: Daniel Vetter > To: Maarten Lankhorst > To: Maxime Ripard > To: Thomas Zimmermann > To: Emma Anholt > To: Jani Nikula > To: Joonas Lahtinen > To: Rodrigo Vivi > To: Tvrtko Ursulin > To: Ben Skeggs > To: Karol Herbst > To: Lyude Paul > To: Chen-Yu Tsai > To: Jernej Skrabec > To: Samuel Holland > Cc: Geert Uytterhoeven > Cc: Mateusz Kwiatkowski > Cc: "Noralf Trønnes" > Cc: Dave Stevenson > Cc: Dom Cobley > Cc: Phil Elwell > Cc: > Cc: linux-kernel@vger.kernel.org > Cc: intel-gfx@lists.freedesktop.org > Cc: nouveau@lists.freedesktop.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-sunxi@lists.linux.dev > Cc: Hans de Goede > Signed-off-by: Maxime Ripard > > --- > Changes in v3: > - Applied some of the fixes to vc4 and sun4i > - Renamed the old TV mode property to legacy_mode > - Fixed a bunch of bisection errors > - Removed most of the redundant TV modes > - Added a new None TV mode to not fall back on NTSC by mistake > - Fixed the mode generation function to match better what is expected > - Added some logging to the mode generation function > - Split the improvements to the named mode parsing logic into separate patches > - Added more checks to the TV atomic_check helper > - Link to v2: https://lore.kernel.org/dri-devel/20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech/ Sorry, this is obviously the v3... Maxime