drm/i915: Fix enabled_planes bitmask

The enabled_planes bitmask was supposed to track logically enabled
planes (ie. fb!=NULL and crtc!=NULL), but instead we end up putting
even disabled planes into the bitmask since
intel_plane_atomic_check_with_state() only takes the early exit
if the plane was disabled and stays disabled. I think I misread
the early said codepath to exit whenever the plane is logically
disabled, which is not true.

So let's fix this up properly and set the bit only when the plane
actually is logically enabled.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Fixes: ee42ec19ca2e ("drm/i915: Track logically enabled planes for hw state")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210305153610.12177-2-ville.syrjala@linux.intel.com
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>

diff --git a/drivers/gpu/drm/i915/display/intel_atomic_plane.c b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
index 4683f98f7e543ab79a5699c1cbe2055693727ee9..c3f2962aa1ebc5507702e7bebafb7c7fa5095b63 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_atomic_plane.c
+++ b/drivers/gpu/drm/i915/display/intel_atomic_plane.c
@@ -317,12 +317,13 @@ int intel_plane_atomic_check_with_state(const struct intel_crtc_state *old_crtc_
        if (!new_plane_state->hw.crtc && !old_plane_state->hw.crtc)
                return 0;
 
-       new_crtc_state->enabled_planes |= BIT(plane->id);
-
        ret = plane->check_plane(new_crtc_state, new_plane_state);
        if (ret)
                return ret;
 
+       if (fb)
+               new_crtc_state->enabled_planes |= BIT(plane->id);
+
        /* FIXME pre-g4x don't work like this */
        if (new_plane_state->uapi.visible)
                new_crtc_state->active_planes |= BIT(plane->id);