According to BSpec this is not needed anymore:
"This workaround is no longer needed since NV12
support is dropped for the affected projects.
"
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181031162845.12419-2-rodrigo.vivi@intel.com
                }
        }
 
-       /*
-        * Display WA #826 (SKL:ALL, BXT:ALL) & #1059 (CNL:A)
-        * disable wm level 1-7 on NV12 planes
-        */
-       if (wp->is_planar && level >= 1 &&
-           (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv) ||
-            IS_CNL_REVID(dev_priv, CNL_REVID_A0, CNL_REVID_A0))) {
-               result->plane_en = false;
-               return 0;
-       }
-
        /* The number of lines are ignored for the level 0 watermark. */
        result->plane_res_b = res_blocks;
        result->plane_res_l = res_lines;