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Diffstat (limited to 'Documentation/gpu/todo.rst')
| -rw-r--r-- | Documentation/gpu/todo.rst | 130 |
1 files changed, 77 insertions, 53 deletions
diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index fb9ad120b141..c57777a24e03 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@@ -37,7 +37,7 @@ Audit each individual driver, make sure it'll work with the generic implementation (there's lots of outdated locking leftovers in various implementations), and then remove it.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 +116,7 @@ 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 @@ -169,7 +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 @@ -194,7 +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 @@ -243,19 +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 ------------------------------------------------------- @@ -264,7 +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 @@ -310,7 +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 @@ -342,7 +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 @@ -372,7 +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 @@ -435,7 +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 @@ -454,14 +441,15 @@ Contact: Thomas Zimmermann <tzimmermann@suse.de> Level: Intermediate -Request memory regions in all drivers -------------------------------------- +Request memory regions in all fbdev drivers +-------------------------------------------- -Go through all drivers and add code to request the memory regions that the -driver uses. This requires adding calls to request_mem_region(), +Old/ancient fbdev drivers do not request their memory properly. +Go through these drivers and add code to request the memory regions +that the driver uses. This requires adding calls to request_mem_region(), pci_request_region() or similar functions. Use helpers for managed cleanup -where possible. - +where possible. Problematic areas include hardware that has exclusive ranges +like VGA. VGA16fb does not request the range as it is expected. Drivers are pretty bad at doing this and there used to be conflicts among DRM and fbdev drivers. Still, it's the correct thing to do. @@ -482,30 +470,50 @@ 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 @@ -551,7 +559,7 @@ 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 @@ -580,7 +588,7 @@ 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 @@ -601,7 +609,7 @@ 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 @@ -621,7 +629,7 @@ 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 @@ -702,7 +710,7 @@ 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 @@ -827,6 +835,22 @@ 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 =========== |