linux.git/include/drm/drm_atomic_helper.h, branch v6.6.13

drm/atomic-helpers: Invoke end_fb_access while owning plane state

2023-12-13T17:45:25+00:00

commit e0f04e41e8eedd4e5a1275f2318df7e1841855f2 upstream.

Invoke drm_plane_helper_funcs.end_fb_access before
drm_atomic_helper_commit_hw_done(). The latter function hands over
ownership of the plane state to the following commit, which might
free it. Releasing resources in end_fb_access then operates on undefined
state. This bug has been observed with non-blocking commits when they
are being queued up quickly.

Here is an example stack trace from the bug report. The plane state has
been free'd already, so the pages for drm_gem_fb_vunmap() are gone.

Unable to handle kernel paging request at virtual address 0000000100000049
[...]
 drm_gem_fb_vunmap+0x18/0x74
 drm_gem_end_shadow_fb_access+0x1c/0x2c
 drm_atomic_helper_cleanup_planes+0x58/0xd8
 drm_atomic_helper_commit_tail+0x90/0xa0
 commit_tail+0x15c/0x188
 commit_work+0x14/0x20

Fix this by running end_fb_access immediately after updating all planes
in drm_atomic_helper_commit_planes(). The existing clean-up helper
drm_atomic_helper_cleanup_planes() now only handles cleanup_fb.

For aborted commits, roll back from drm_atomic_helper_prepare_planes()
in the new helper drm_atomic_helper_unprepare_planes(). This case is
different from regular cleanup, as we have to release the new state;
regular cleanup releases the old state. The new helper also invokes
cleanup_fb for all planes.

The changes mostly involve DRM's atomic helpers. Only two drivers, i915
and nouveau, implement their own commit function. Update them to invoke
drm_atomic_helper_unprepare_planes(). Drivers with custom commit_tail
function do not require changes.

v4:
	* fix documentation (kernel test robot)
v3:
	* add drm_atomic_helper_unprepare_planes() for rolling back
	* use correct state for end_fb_access
v2:
	* fix test in drm_atomic_helper_cleanup_planes()

Reported-by: Alyssa Ross 
Closes: https://lore.kernel.org/dri-devel/87leazm0ya.fsf@alyssa.is/
Suggested-by: Daniel Vetter 
Fixes: 94d879eaf7fb ("drm/atomic-helper: Add {begin,end}_fb_access to plane helpers")
Tested-by: Alyssa Ross 
Reviewed-by: Alyssa Ross 
Signed-off-by: Thomas Zimmermann 
Cc:  # v6.2+
Link: https://patchwork.freedesktop.org/patch/msgid/20231204083247.22006-1-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman

drm/atomic-helper: Add atomic_enable plane-helper callback

2023-02-20T14:19:23+00:00

Add atomic_enable to struct drm_plane_helper_funcs. It enables a
plane independently from updating the plane's content. As such, it is
the inverse of the atomic_disable plane helper. Useful for hardware
where plane enable state is independent from plane content.

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Link: https://patchwork.freedesktop.org/patch/msgid/20230209154107.30680-2-tzimmermann@suse.de

drm/atomic-helper: Replace drm_atomic_helper_check_crtc_state()

2022-10-08T13:26:55+00:00

Rename the atomic helper function drm_atomic_helper_check_crtc_state()
to drm_atomic_helper_check_crtc_primary_plane() and only check for an
attached primary plane. Adapt callers.

Instead of having one big function to check for various CRTC state
conditions, we rather want smaller functions that drivers can pick
individually.

v5:
	* rebase on top of udl changes

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Link: https://patchwork.freedesktop.org/patch/msgid/20221007124338.24152-3-tzimmermann@suse.de

drm: drm_atomic_helper: Add a new helper to deal with the writeback connector validation

2022-09-05T21:12:16+00:00

Add a helper function to validate the connector configuration received in
the encoder atomic_check by the drivers.

So the drivers don't need to do these common validations themselves.

V2: Move the format verification to a new helper at the drm_atomic_helper.c
    (Thomas Zimmermann).
V3: Format check improvements (Leandro Ribeiro).
    Minor improvements(Thomas Zimmermann).
V5: Fix some grammar issues in the commit message (André Almeida).

Reviewed-by: Melissa Wen 
Signed-off-by: Igor Torrente 
Signed-off-by: Melissa Wen 
Link: https://patchwork.freedesktop.org/patch/msgid/20220905190811.25024-4-igormtorrente@gmail.com

drm/atomic-helper: Remove _HELPER_ infix from DRM_PLANE_HELPER_NO_SCALING

2022-07-26T16:42:00+00:00

Rename DRM_PLANE_HELPER_NO_SCALING to DRM_PLANE_NO_SCALING. The constant
is not really a helper, but rather a characteristic of the plane itself.

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20220720083058.15371-4-tzimmermann@suse.de

drm/atomic-helper: Move DRM_PLANE_HELPER_NO_SCALING to atomic helpers

2022-07-26T16:41:56+00:00

The macro DRM_PLANE_HELPER_NO_SCALING is only useful with the interfaces
in drm_atomic_helper.h, but defined in drm_plane_helper.h. So half of
DRM includes the latter header file for using this macro. Move the macro
and remove the include statements.

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20220720083058.15371-3-tzimmermann@suse.de

drm/atomic-helper: Add helper drm_atomic_helper_check_crtc_state()

2022-06-27T09:10:43+00:00

Add drm_atomic_helper_check_crtc_state(), which contains tests common
to many CRTCs. The first added test verifies that an enabled CRTC has
at least one enabled primary plane.

Signed-off-by: Thomas Zimmermann 
Acked-by: Jocelyn Falempe 
Link: https://patchwork.freedesktop.org/patch/msgid/20220617103226.25617-2-tzimmermann@suse.de

drm: automatic legacy gamma support

2020-12-15T13:46:03+00:00

To support legacy gamma ioctls the drivers need to set
drm_crtc_funcs.gamma_set either to a custom implementation or to
drm_atomic_helper_legacy_gamma_set. Most of the atomic drivers do the
latter.

We can simplify this by making the core handle it automatically.

Move the drm_atomic_helper_legacy_gamma_set() functionality into
drm_color_mgmt.c to make drm_mode_gamma_set_ioctl() use
drm_crtc_funcs.gamma_set if set or GAMMA_LUT property if not.

Signed-off-by: Tomi Valkeinen 
Reviewed-by: Laurent Pinchart 
Reviewed-by: Philippe Cornu 
Link: https://patchwork.freedesktop.org/patch/msgid/20201211114237.213288-2-tomi.valkeinen@ti.com

drm: fix some kernel-doc markups

2020-11-16T19:48:20+00:00

Some identifiers have different names between their prototypes
and the kernel-doc markup.

Others need to be fixed, as kernel-doc markups should use this format:
        identifier - description

Signed-off-by: Mauro Carvalho Chehab 
Acked-by: Jani Nikula 
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/12d4ca26f6843618200529ce5445063734d38c04.1605521731.git.mchehab+huawei@kernel.org

drm/atomic-helper: Extract drm_atomic_helper_calc_timestamping_constants()

2020-09-14T19:36:44+00:00

Put the vblank timestamping constants update loop into its own
function. It has no business living inside
drm_atomic_helper_update_legacy_modeset_state() so we'll be wanting
to move it out entirely. As a first step we'll still call it
from drm_atomic_helper_update_legacy_modeset_state().

v2: Drop comment about 'legacy state' in the new function

Signed-off-by: Ville Syrjälä 
Link: https://patchwork.freedesktop.org/patch/msgid/20200907120026.6360-1-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter