diff options
Diffstat (limited to 'Documentation/gpu')
| -rw-r--r-- | Documentation/gpu/drm-mm.rst | 4 | ||||
| -rw-r--r-- | Documentation/gpu/i915.rst | 6 | ||||
| -rw-r--r-- | Documentation/gpu/todo.rst | 74 | ||||
| -rw-r--r-- | Documentation/gpu/vkms.rst | 99 |
4 files changed, 124 insertions, 59 deletions
diff --git a/Documentation/gpu/drm-mm.rst b/Documentation/gpu/drm-mm.rst index 9abee1589c1e..21be6deadc12 100644 --- a/Documentation/gpu/drm-mm.rst +++ b/Documentation/gpu/drm-mm.rst @@ -182,11 +182,11 @@ acquired and release by calling drm_gem_object_get() and drm_gem_object_put() respectively. When the last reference to a GEM object is released the GEM core calls -the :c:type:`struct drm_driver <drm_driver>` gem_free_object_unlocked +the :c:type:`struct drm_gem_object_funcs <gem_object_funcs>` free operation. That operation is mandatory for GEM-enabled drivers and must free the GEM object and all associated resources. -void (\*gem_free_object) (struct drm_gem_object \*obj); Drivers are +void (\*free) (struct drm_gem_object \*obj); Drivers are responsible for freeing all GEM object resources. This includes the resources created by the GEM core, which need to be released with drm_gem_object_release(). diff --git a/Documentation/gpu/i915.rst b/Documentation/gpu/i915.rst index cff1f154b473..20868f3d0123 100644 --- a/Documentation/gpu/i915.rst +++ b/Documentation/gpu/i915.rst @@ -118,6 +118,12 @@ Atomic Plane Helpers .. kernel-doc:: drivers/gpu/drm/i915/display/intel_atomic_plane.c :internal: +Asynchronous Page Flip +---------------------- + +.. kernel-doc:: drivers/gpu/drm/i915/display/intel_display.c + :doc: asynchronous flip implementation + Output Probing -------------- diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index b0ea17da8ff6..009d8e6c7e3c 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -105,6 +105,10 @@ converted over to the new infrastructure. One issue with the helpers is that they require that drivers handle completion events for atomic commits correctly. But fixing these bugs is good anyway. +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 Level: Advanced @@ -149,7 +153,7 @@ have to keep track of that lock and either call ``unreference`` or ``unreference_locked`` depending upon context. Core GEM doesn't have a need for ``struct_mutex`` any more since kernel 4.8, -and there's a ``gem_free_object_unlocked`` callback for any drivers which are +and there's a GEM object ``free`` callback for any drivers which are entirely ``struct_mutex`` free. For drivers that need ``struct_mutex`` it should be replaced with a driver- @@ -197,13 +201,28 @@ 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. Current generic fbdev emulation -expects the framebuffer in system memory (or system-like memory). +atomic modesetting and GEM vmap support. Historically, generic fbdev emulation +expected the framebuffer in system memory or system-like memory. By employing +struct dma_buf_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 +------------------------------------------------------- + +A number of callback functions in drm_fbdev_fb_ops could benefit from +being rewritten without dependencies on the fbdev module. Some of the +helpers could further benefit from using struct dma_buf_map instead of +raw pointers. + +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Daniel Vetter + +Level: Advanced + + drm_framebuffer_funcs and drm_mode_config_funcs.fb_create cleanup ----------------------------------------------------------------- @@ -273,6 +292,27 @@ Contact: Daniel Vetter, Noralf Tronnes Level: Advanced +Garbage collect fbdev scrolling acceleration +-------------------------------------------- + +Scroll acceleration is disabled in fbcon by hard-wiring p->scrollmode = +SCROLL_REDRAW. There's a ton of code this will allow us to remove: + +- lots of code in fbcon.c + +- a bunch of the hooks in fbcon_ops, maybe the remaining hooks could be called + directly instead of the function table (with a switch on p->rotate) + +- fb_copyarea is unused after this, and can be deleted from all drivers + +Note that not all acceleration code can be deleted, since clearing and cursor +support is still accelerated, which might be good candidates for further +deletion projects. + +Contact: Daniel Vetter + +Level: Intermediate + idr_init_base() --------------- @@ -289,11 +329,8 @@ struct drm_gem_object_funcs --------------------------- GEM objects can now have a function table instead of having the callbacks on the -DRM driver struct. This is now the preferred way and drivers can be moved over. - -We also need a 2nd version of the CMA define that doesn't require the -vmapping to be present (different hook for prime importing). Plus this needs to -be rolled out to all drivers using their own implementations, too. +DRM driver struct. This is now the preferred way. Callbacks in drivers have been +converted, except for struct drm_driver.gem_prime_mmap. Level: Intermediate @@ -449,6 +486,24 @@ Contact: Ville Syrjälä, Daniel Vetter Level: Intermediate +Use struct dma_buf_map throughout codebase +------------------------------------------ + +Pointers to shared device memory are stored in struct dma_buf_map. Each +instance knows whether it refers to system or I/O memory. Most of the DRM-wide +interface have been converted to use struct dma_buf_map, but implementations +often still use raw pointers. + +The task is to use struct dma_buf_map where it makes sense. + +* Memory managers should use struct dma_buf_map for dma-buf-imported buffers. +* TTM might benefit from using struct dma_buf_map internally. +* Framebuffer copying and blitting helpers should operate on struct dma_buf_map. + +Contact: Thomas Zimmermann <tzimmermann@suse.de>, Christian König, Daniel Vetter + +Level: Intermediate + Core refactorings ================= @@ -518,9 +573,6 @@ There's a bunch of issues with it: this (together with the drm_minor->drm_device move) would allow us to remove debugfs_init. -- Drop the return code and error checking from all debugfs functions. Greg KH is - working on this already. - Contact: Daniel Vetter Level: Intermediate diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst index 61586fc861bb..13bab1d93bb3 100644 --- a/Documentation/gpu/vkms.rst +++ b/Documentation/gpu/vkms.rst @@ -10,36 +10,24 @@ TODO ==== -CRC API Improvements --------------------- - -- Optimize CRC computation ``compute_crc()`` and plane blending ``blend()`` - -- Use the alpha value to blend vaddr_src with vaddr_dst instead of - overwriting it in ``blend()``. - -- Add igt test to check cleared alpha value for XRGB plane format. - -- Add igt test to check extreme alpha values i.e. fully opaque and fully - transparent (intermediate values are affected by hw-specific rounding modes). - -Runtime Configuration ---------------------- - -We want to be able to reconfigure vkms instance without having to reload the -module. Use/Test-cases: - -- Hotplug/hotremove connectors on the fly (to be able to test DP MST handling of - compositors). +If you want to do any of the items listed below, please share your interest +with VKMS maintainers. -- Configure planes/crtcs/connectors (we'd need some code to have more than 1 of - them first). +IGT better support +------------------ -- Change output configuration: Plug/unplug screens, change EDID, allow changing - the refresh rate. +- Investigate: (1) test cases on kms_plane that are failing due to timeout on + capturing CRC; (2) when running kms_flip test cases in sequence, some + successful individual test cases are failing randomly. -The currently proposed solution is to expose vkms configuration through -configfs. All existing module options should be supported through configfs too. +- VKMS already has support for vblanks simulated via hrtimers, which can be + tested with kms_flip test; in some way, we can say that VKMS already mimics + the real hardware vblank. However, we also have virtual hardware that does + not support vblank interrupt and completes page_flip events right away; in + this case, compositor developers may end up creating a busy loop on virtual + hardware. It would be useful to support Virtual Hardware behavior in VKMS + because this can help compositor developers to test their features in + multiple scenarios. Add Plane Features ------------------ @@ -55,34 +43,50 @@ There's lots of plane features we could add support for: - Additional buffer formats, especially YUV formats for video like NV12. Low/high bpp RGB formats would also be interesting. -- Async updates (currently only possible on cursor plane using the legacy cursor - api). +- Async updates (currently only possible on cursor plane using the legacy + cursor api). + +For all of these, we also want to review the igt test coverage and make sure +all relevant igt testcases work on vkms. + +Prime Buffer Sharing +-------------------- -For all of these, we also want to review the igt test coverage and make sure all -relevant igt testcases work on vkms. +- Syzbot report - WARNING in vkms_gem_free_object: + https://syzkaller.appspot.com/bug?extid=e7ad70d406e74d8fc9d0 + +Runtime Configuration +--------------------- + +We want to be able to reconfigure vkms instance without having to reload the +module. Use/Test-cases: + +- Hotplug/hotremove connectors on the fly (to be able to test DP MST handling + of compositors). + +- Configure planes/crtcs/connectors (we'd need some code to have more than 1 of + them first). + +- Change output configuration: Plug/unplug screens, change EDID, allow changing + the refresh rate. + +The currently proposed solution is to expose vkms configuration through +configfs. All existing module options should be supported through configfs +too. Writeback support ----------------- -Currently vkms only computes a CRC for each frame. Once we have additional plane -features, we could write back the entire composited frame, and expose it as: +- The writeback and CRC capture operations share the use of composer_enabled + boolean to ensure vblanks. Probably, when these operations work together, + composer_enabled needs to refcounting the composer state to proper work. -- Writeback connector. This is useful for testing compositors if you don't have - hardware with writeback support. +- Add support for cloned writeback outputs and related test cases using a + cloned output in the IGT kms_writeback. - As a v4l device. This is useful for debugging compositors on special vkms configurations, so that developers see what's really going on. -Prime Buffer Sharing --------------------- - -We already have vgem, which is a gem driver for testing rendering, similar to -how vkms is for testing the modeset side. Adding buffer sharing support to vkms -allows us to test them together, to test synchronization and lots of other -features. Also, this allows compositors to test whether they work correctly on -SoC chips, where the display and rendering is very often split between 2 -drivers. - Output Features --------------- @@ -93,7 +97,10 @@ Output Features - Add support for link status, so that compositors can validate their runtime fallbacks when e.g. a Display Port link goes bad. -- All the hotplug handling describe under "Runtime Configuration". +CRC API Improvements +-------------------- + +- Optimize CRC computation ``compute_crc()`` and plane blending ``blend()`` Atomic Check using eBPF ----------------------- |