i915 sometimes needs to disable planes in the middle of an atomic commit, and then reenable them later in the same commit. Because of this, we can't make the assumption that the state of the plane actually changed. Since the state of the plane hasn't actually changed, neither have it's watermarks. And if the watermarks hasn't changed then we haven't populated skl_results with anything, which means we'll end up zeroing out a plane's watermarks in the middle of the atomic commit without restoring them later. Signed-off-by: Lyude <cpaul@xxxxxxxxxx> Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> Fixes: 62e0fb880123 ("drm/i915/skl: Update plane watermarks atomically during plane updates") Signed-off-by: Lyude <cpaul@xxxxxxxxxx> --- drivers/gpu/drm/i915/intel_display.c | 8 +++++++- drivers/gpu/drm/i915/intel_sprite.c | 10 ++++++++-- 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index e4e6141..8faf738 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -3448,7 +3448,13 @@ static void skylake_disable_primary_plane(struct drm_plane *primary, struct intel_crtc *intel_crtc = to_intel_crtc(crtc); int pipe = intel_crtc->pipe; - skl_write_plane_wm(intel_crtc, &dev_priv->wm.skl_results, 0); + /* + * We only populate skl_results on watermark updates, and if the + * plane's visiblity isn't actually changing neither is it's + * watermarks. + */ + if (!crtc->primary->state->visible) + skl_write_plane_wm(intel_crtc, &dev_priv->wm.skl_results, 0); I915_WRITE(PLANE_CTL(pipe, 0), 0); I915_WRITE(PLANE_SURF(pipe, 0), 0); diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c index 0df783a..f51a70c 100644 --- a/drivers/gpu/drm/i915/intel_sprite.c +++ b/drivers/gpu/drm/i915/intel_sprite.c @@ -292,8 +292,14 @@ skl_disable_plane(struct drm_plane *dplane, struct drm_crtc *crtc) const int pipe = intel_plane->pipe; const int plane = intel_plane->plane + 1; - skl_write_plane_wm(to_intel_crtc(crtc), &dev_priv->wm.skl_results, - plane); + /* + * We only populate skl_results on watermark updates, and if the + * plane's visiblity isn't actually changing neither is it's + * watermarks. + */ + if (!dplane->state->visible) + skl_write_plane_wm(to_intel_crtc(crtc), + &dev_priv->wm.skl_results, plane); I915_WRITE(PLANE_CTL(pipe, plane), 0); -- 2.7.4 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx