icl and tgl are still affected by the modulo 4 PLANE_OFFSET.y
underrun issue. Reject such configurations on all gen9+ platforms.

Can be reproduced easily with the following sequence of
hardware poking:
while {
  write FBC_CTL.enable=1
  wait for vblank

  write PLANE_OFFSET .x=0 .y=32
  write PLANE_SURF
  wait for vblank

  # if PLANE_OFFSET.y is multiple of 4 the underrun won't happen
  write PLANE_OFFSET .x=0 .y=31
  write PLANE_SURF
  wait for vblank

  # extra vblank wait is required here presumably
  # to get FBC into the proper state
  wait for vblank

  write FBC_CTL.enable=0
  # underrun happens some time after FBC disable
  wait for vblank
}

Both 8888 and 565 pixel formats and all tilinga formats
seem affected. Reproduced on KBL/GLK/ICL/TGL. BDW confirmed
not affected.

Closes: https://gitlab.freedesktop.org/drm/intel/issues/792Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191213133453.22152-1-ville.syrjala@linux.intel.comReviewed-by: Imre Deak <imre.deak@intel.com>