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-rw-r--r--Documentation/gpu/drm-mm.rst4
-rw-r--r--Documentation/gpu/todo.rst16
-rw-r--r--Documentation/gpu/vkms.rst99
3 files changed, 62 insertions, 57 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/todo.rst b/Documentation/gpu/todo.rst
index b0ea17da8ff6..6b224ef14455 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-
@@ -289,11 +293,8 @@ 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
@@ -518,9 +519,6 @@ 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
-----------------------