We no longer use intel_crtc->wm.active for watermarks any more, which was incorrect. But this uncovered a bug in sanitize_watermarks(), which meant that we wrote the correct watermarks, but the next update would still use the wrong hw watermarks for calculating. This caused all further updates to fail with -EINVAL and the log would reveal an error like the one below:

[ 10.043902] [drm:ilk_validate_wm_level.part.8 [i915]] Sprite WM0 too large 56 (max 0) [ 10.043960] [drm:ilk_validate_pipe_wm [i915]] LP0 watermark invalid [ 10.044030] [drm:intel_crtc_atomic_check [i915]] No valid intermediate pipe watermarks are possible

Signed-off-by: Maarten Lankhorst maarten.lankhorst@linux.intel.com Fixes: b6b178a77210 ("drm/i915: Calculate ironlake intermediate watermarks correctly, v2.") Cc: stable@vger.kernel.org #v4.8+ --- drivers/gpu/drm/i915/intel_display.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 84817ccc5305..17665ee06c9a 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -14442,6 +14442,8 @@ static void sanitize_watermarks(struct drm_device *dev)

cs->wm.need_postvbl_update = true; dev_priv->display.optimize_watermarks(intel_state, cs); + + to_intel_crtc_state(crtc->state)->wm = cs->wm; }

put_state: