[Intel-gfx] [PATCH v2 1/6] drm/i915: Update watermark state correctly in sanitize_watermarks

[Maarten Lankhorst]

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 at linux.intel.com>
Fixes: b6b178a77210 ("drm/i915: Calculate ironlake intermediate watermarks correctly, v2.")
Cc: stable at 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:
-- 
2.15.0