Re: [PATCH v3 0/3] drm/i915/fbc: Dirty rectangle bounding and CFB

[Jani Nikula <jani.nikula@linux.intel.com>]

On Wed, 23 Sep 2026, Austin Hu <austin.hu@intel.com> wrote:
> This series updates Intel FBC dirty rectangle handling and refactors plane
> update checks:

Please base your work on drm-tip and send new versions of the series as
standalone threads instead of in-reply-to previous versions.

BR,
Jani.


>
> 1. Moves intel_fbc_can_flip_nuke() higher up in intel_fbc.c to avoid a
>    forward declaration in subsequent FBC checks. (No functional change)
> 2. Clamps FBC dirty rectangle bounds to valid surface limits [y_offset,
>    y_end] and adds logging for out-of-bounds coordinates, including
>    handling for 180-degree plane rotation.
> 3. Tracks plane state attribute changes during atomic commits. When FBC
>    Dirty Rectangle mode is active, partial updates only apply to surface
>    address changes (PLANE_SURF). Modifications to any other plane state
>    parameters require fetching full-plane pixel data from memory to
>    re-compress and update the entire CFB in stolen memory. Once fully
>    re-compressed, subsequent atomic commits can resume selective dirty
>    rectangle updates.
>
> v2 -> v3 changes:
>   - Split function reordering into a separate standalone commit (v3 1/3) to
>     avoid mixing movement and functional changes, per maintainer feedback.
>   - Rebased onto latest drm-tip.
>
> v1 -> v2 changes:
>   - Reused intel_fbc_can_flip_nuke() for plane update state checks as
>     suggested.
>   - Added plane Y-coordinate plane view checking (color_plane[0].y)
>     alongside X.
>
> Austin Hu (2):
>   drm/i915/display/fbc: Move intel_fbc_can_flip_nuke() higher up
>   drm/i915/fbc: nuke CFB if Plane setting (except for surf addr) changes
>
> Charlton Lin (1):
>   drm/i915/fbc: fbc_dirty_rect restrictions and logging
>
>  drivers/gpu/drm/i915/display/intel_fbc.c | 192 +++++++++++++++++------
>  1 file changed, 141 insertions(+), 51 deletions(-)

-- 
Jani Nikula, Intel