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Diffstat (limited to 'Documentation/gpu/todo.rst')
| -rw-r--r-- | Documentation/gpu/todo.rst | 140 |
1 files changed, 93 insertions, 47 deletions
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index 41a264bf84ce..256d0d1cb216 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -37,7 +37,7 @@ Audit each individual driver, make sure it'll work with the generic implementation (there's lots of outdated locking leftovers in various implementations), and then remove it. -Contact: Daniel Vetter, respective driver maintainers +Contact: Simona Vetter, respective driver maintainers Level: Intermediate @@ -61,7 +61,7 @@ do by directly using the new atomic helper driver callbacks. .. [2] https://lwn.net/Articles/653071/ .. [3] https://lwn.net/Articles/653466/ -Contact: Daniel Vetter, respective driver maintainers +Contact: Simona Vetter, respective driver maintainers Level: Advanced @@ -75,7 +75,7 @@ helper should also be moved from drm_plane_helper.c to the atomic helpers, to avoid confusion - the other helpers in that file are all deprecated legacy helpers. -Contact: Ville Syrjälä, Daniel Vetter, driver maintainers +Contact: Ville Syrjälä, Simona Vetter, driver maintainers Level: Advanced @@ -97,7 +97,7 @@ with the current helpers: - Then we could go through all the drivers and remove the more-or-less confused checks for plane_state->fb and plane_state->crtc. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Advanced @@ -116,7 +116,30 @@ Somewhat related is the legacy_cursor_update hack, which should be replaced with the new atomic_async_check/commit functionality in the helpers in drivers that still look at that flag. -Contact: Daniel Vetter, respective driver maintainers +Contact: Simona Vetter, respective driver maintainers + +Level: Advanced + +Rename drm_atomic_state +----------------------- + +The KMS framework uses two slightly different definitions for the ``state`` +concept. For a given object (plane, CRTC, encoder, etc., so +``drm_$OBJECT_state``), the state is the entire state of that object. However, +at the device level, ``drm_atomic_state`` refers to a state update for a +limited number of objects. + +The state isn't the entire device state, but only the full state of some +objects in that device. This is confusing to newcomers, and +``drm_atomic_state`` should be renamed to something clearer like +``drm_atomic_commit``. + +In addition to renaming the structure itself, it would also imply renaming some +related functions (``drm_atomic_state_alloc``, ``drm_atomic_state_get``, +``drm_atomic_state_put``, ``drm_atomic_state_init``, +``__drm_atomic_state_free``, etc.). + +Contact: Maxime Ripard <mripard@kernel.org> Level: Advanced @@ -146,7 +169,7 @@ interfaces to fix these issues: ``_helper_funcs`` since they are not part of the core ABI. There's a ``FIXME`` comment in the kerneldoc for each such case in ``drm_crtc.h``. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Intermediate @@ -171,7 +194,7 @@ performance-critical drivers it might also be better to go with a more fine-grained per-buffer object and per-context lockings scheme. Currently only the ``msm`` and `i915` drivers use ``struct_mutex``. -Contact: Daniel Vetter, respective driver maintainers +Contact: Simona Vetter, respective driver maintainers Level: Advanced @@ -220,19 +243,6 @@ Contact: Maintainer of the driver you plan to convert Level: Intermediate -Convert drivers to use drm_fbdev_generic_setup() ------------------------------------------------- - -Most drivers can use drm_fbdev_generic_setup(). Driver have to implement -atomic modesetting and GEM vmap support. Historically, generic fbdev emulation -expected the framebuffer in system memory or system-like memory. By employing -struct iosys_map, drivers with frambuffers in I/O memory can be supported -as well. - -Contact: Maintainer of the driver you plan to convert - -Level: Intermediate - Reimplement functions in drm_fbdev_fb_ops without fbdev ------------------------------------------------------- @@ -241,7 +251,7 @@ being rewritten without dependencies on the fbdev module. Some of the helpers could further benefit from using struct iosys_map instead of raw pointers. -Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Simona Vetter Level: Advanced @@ -287,7 +297,7 @@ Various hold-ups: version of the varios drm_gem_fb_create functions. Maybe called drm_gem_fb_create/_with_dirty/_with_funcs as needed. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Intermediate @@ -319,7 +329,7 @@ everything after it has done the write-protect/mkwrite trickery: Might be good to also have some igt testcases for this. -Contact: Daniel Vetter, Noralf Tronnes +Contact: Simona Vetter, Noralf Tronnes Level: Advanced @@ -349,7 +359,7 @@ between setting up the &drm_driver structure and calling drm_dev_register(). - Once all drivers are converted, remove the load/unload callbacks. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Intermediate @@ -412,7 +422,7 @@ The task is to use struct iosys_map where it makes sense. * TTM might benefit from using struct iosys_map internally. * Framebuffer copying and blitting helpers should operate on struct iosys_map. -Contact: Thomas Zimmermann <tzimmermann@suse.de>, Christian König, Daniel Vetter +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Christian König, Simona Vetter Level: Intermediate @@ -459,30 +469,50 @@ Contact: Thomas Zimmermann <tzimmermann@suse.de> Level: Starter -Clean up checks for already prepared/enabled in panels ------------------------------------------------------- +Remove disable/unprepare in remove/shutdown in panel-simple and panel-edp +------------------------------------------------------------------------- + +As of commit d2aacaf07395 ("drm/panel: Check for already prepared/enabled in +drm_panel"), we have a check in the drm_panel core to make sure nobody +double-calls prepare/enable/disable/unprepare. Eventually that should probably +be turned into a WARN_ON() or somehow made louder. + +At the moment, we expect that we may still encounter the warnings in the +drm_panel core when using panel-simple and panel-edp. Since those panel +drivers are used with a lot of different DRM modeset drivers they still +make an extra effort to disable/unprepare the panel themsevles at shutdown +time. Specifically we could still encounter those warnings if the panel +driver gets shutdown() _before_ the DRM modeset driver and the DRM modeset +driver properly calls drm_atomic_helper_shutdown() in its own shutdown() +callback. Warnings could be avoided in such a case by using something like +device links to ensure that the panel gets shutdown() after the DRM modeset +driver. + +Once all DRM modeset drivers are known to shutdown properly, the extra +calls to disable/unprepare in remove/shutdown in panel-simple and panel-edp +should be removed and this TODO item marked complete. -In a whole pile of panel drivers, we have code to make the -prepare/unprepare/enable/disable callbacks behave as no-ops if they've already -been called. To get some idea of the duplicated code, try:: +Contact: Douglas Anderson <dianders@chromium.org> - git grep 'if.*>prepared' -- drivers/gpu/drm/panel - git grep 'if.*>enabled' -- drivers/gpu/drm/panel +Level: Intermediate -In the patch ("drm/panel: Check for already prepared/enabled in drm_panel") -we've moved this check to the core. Now we can most definitely remove the -check from the individual panels and save a pile of code. +Transition away from using mipi_dsi_*_write_seq() +------------------------------------------------- -In adition to removing the check from the individual panels, it is believed -that even the core shouldn't need this check and that should be considered -an error if other code ever relies on this check. The check in the core -currently prints a warning whenever something is relying on this check with -dev_warn(). After a little while, we likely want to promote this to a -WARN(1) to help encourage folks not to rely on this behavior. +The macros mipi_dsi_generic_write_seq() and mipi_dsi_dcs_write_seq() are +non-intuitive because, if there are errors, they return out of the *caller's* +function. We should move all callers to use mipi_dsi_generic_write_seq_multi() +and mipi_dsi_dcs_write_seq_multi() macros instead. + +Once all callers are transitioned, the macros and the functions that they call, +mipi_dsi_generic_write_chatty() and mipi_dsi_dcs_write_buffer_chatty(), can +probably be removed. Alternatively, if people feel like the _multi() variants +are overkill for some use cases, we could keep the mipi_dsi_*_write_seq() +variants but change them not to return out of the caller. Contact: Douglas Anderson <dianders@chromium.org> -Level: Starter/Intermediate +Level: Starter Core refactorings @@ -528,7 +558,7 @@ This is a really varied tasks with lots of little bits and pieces: <https://lore.kernel.org/lkml/1446217392-11981-1-git-send-email-alexandru.murtaza@intel.com/>`_ for some example code that could be reused. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Advanced @@ -557,7 +587,7 @@ There's a bunch of issues with it: this (together with the drm_minor->drm_device move) would allow us to remove debugfs_init. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Intermediate @@ -578,7 +608,7 @@ Both these problems can be solved by switching over to drmm_kzalloc(), and the various convenience wrappers provided, e.g. drmm_crtc_alloc_with_planes(), drmm_universal_plane_alloc(), ... and so on. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Intermediate @@ -598,7 +628,7 @@ cache is also tied to &drm_gem_object.import_attach. Meanwhile we paper over this problem for USB devices by fishing out the USB host controller device, as long as that supports DMA. Otherwise importing can still needlessly fail. -Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Simona Vetter Level: Advanced @@ -679,7 +709,7 @@ Plan to fix this: 2. In all, only look at one of the three status bits set by the above helpers. 3. Remove the other two status bits. -Contact: Daniel Vetter +Contact: Simona Vetter Level: Intermediate @@ -804,6 +834,22 @@ Contact: Javier Martinez Canillas <javierm@redhat.com> Level: Advanced +Querying errors from drm_syncobj +================================ + +The drm_syncobj container can be used by driver independent code to signal +complection of submission. + +One minor feature still missing is a generic DRM IOCTL to query the error +status of binary and timeline drm_syncobj. + +This should probably be improved by implementing the necessary kernel interface +and adding support for that in the userspace stack. + +Contact: Christian König + +Level: Starter + Outside DRM =========== |