diff options
Diffstat (limited to 'include/drm/drm_modeset_helper_vtables.h')
-rw-r--r-- | include/drm/drm_modeset_helper_vtables.h | 41 |
1 files changed, 40 insertions, 1 deletions
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h index fafa70ac1337..d9f2254a039a 100644 --- a/include/drm/drm_modeset_helper_vtables.h +++ b/include/drm/drm_modeset_helper_vtables.h @@ -1184,11 +1184,20 @@ struct drm_plane_helper_funcs { * can call drm_gem_plane_helper_prepare_fb() from their @prepare_fb * hook. * + * The resources acquired in @prepare_fb persist after the end of + * the atomic commit. Resources that can be release at the commit's end + * should be acquired in @begin_fb_access and released in @end_fb_access. + * For example, a GEM buffer's pin operation belongs into @prepare_fb to + * keep the buffer pinned after the commit. But a vmap operation for + * shadow-plane helpers belongs into @begin_fb_access, so that atomic + * helpers remove the mapping at the end of the commit. + * * The helpers will call @cleanup_fb with matching arguments for every * successful call to this hook. * * This callback is used by the atomic modeset helpers and by the - * transitional plane helpers, but it is optional. + * transitional plane helpers, but it is optional. See @begin_fb_access + * for preparing per-commit resources. * * RETURNS: * @@ -1212,6 +1221,36 @@ struct drm_plane_helper_funcs { struct drm_plane_state *old_state); /** + * @begin_fb_access: + * + * This hook prepares the plane for access during an atomic commit. + * In contrast to @prepare_fb, resources acquired in @begin_fb_access, + * are released at the end of the atomic commit in @end_fb_access. + * + * For example, with shadow-plane helpers, the GEM buffer's vmap + * operation belongs into @begin_fb_access, so that the buffer's + * memory will be unmapped at the end of the commit in @end_fb_access. + * But a GEM buffer's pin operation belongs into @prepare_fb + * to keep the buffer pinned after the commit. + * + * The callback is used by the atomic modeset helpers, but it is optional. + * See @end_fb_cleanup for undoing the effects of @begin_fb_access and + * @prepare_fb for acquiring resources until the next pageflip. + * + * Returns: + * 0 on success, or a negative errno code otherwise. + */ + int (*begin_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state); + + /** + * @end_fb_access: + * + * This hook cleans up resources allocated by @begin_fb_access. It it called + * at the end of a commit for the new plane state. + */ + void (*end_fb_access)(struct drm_plane *plane, struct drm_plane_state *new_plane_state); + + /** * @atomic_check: * * Drivers should check plane specific constraints in this hook. |