On 29.1.2019 14.57, Gwan-gyeong Mun wrote:
Enabling FBC on a plane which has a combination of a 180-degree rotation
with having a Height that isn't divisible by 4 causes FIFO underrun,
so disable FBC on such a config.

Testcase: igt/kms_rotation_crc/multiplane-rotation-cropping-top
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105604

Signed-off-by: Gwan-gyeong Mun <gwan-gyeong....@intel.com>
---
  drivers/gpu/drm/i915/intel_fbc.c | 12 ++++++++++++
  1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c
index ccd5e110a19c..de4b5781922c 100644
--- a/drivers/gpu/drm/i915/intel_fbc.c
+++ b/drivers/gpu/drm/i915/intel_fbc.c
@@ -793,6 +793,18 @@ static bool intel_fbc_can_activate(struct intel_crtc *crtc)
                return false;
        }
+ /*
+        * Work around a problem on GEN9 HW, where enabling FBC on a plane
+        * which has a combination of a 180-degree rotation with having a Height
+        * that isn't divisible by 4 causes FIFO underrun.
+        */
+       if (IS_GEN(dev_priv, 9) &&
+           (cache->plane.rotation == DRM_MODE_ROTATE_180) &&
+           (fbc->state_cache.plane.src_h & 3)) {
+               fbc->no_fbc_reason = "plane has a combination of a 180-degree 
rotation with a misaligned Height";
+               return false;
+       }
+
        return true;
  }

I see there extra parenthesis but it's in line with style used just above this piece of code so I guess it's ok.

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikk...@gmail.com>
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to