-
Imre Deak authored
The scaler allocation code depends on a non-zero default value for the crtc scaler_id, so make sure we initialize the scaler state accordingly even if the crtc is off. This fixes at least an initial YUV420 modeset (added in a follow-up patchset by Shashank) when booting with the screen off: after the initial HW readout and modeset which enables the scaler a subsequent modeset will disable the scaler which isn't properly allocated. This results in a funky HW state where the pipe scaler HW registers can't be modified and the normally black screen is grey and shifted to the right or jitters. The problem was revealed by Shashank's YUV420 patchset and first reported by Ville. v2: - In the stable tag also include versions which need backporting (Jani) Cc: Jani Nikula <jani.nikula@intel.com> Cc: Shashank Sharma <shashank.sharma@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chandra Konduru <chandra.konduru@intel.com> Cc: Matt Roper <matthew.d.roper@intel.com> Cc: <stable@vger.kernel.org> # 4.2.x Reported-by:
Ville Syrjälä <ville.syrjala@linux.intel.com> Fixes: a1b2278e ("drm/i915: skylake panel fitting using shared scalers") Signed-off-by:
Imre Deak <imre.deak@intel.com> Reviewed-by:
Mahesh Kumar <mahesh1.kumar@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170720112820.26816-1-imre.deak@intel.comSigned-off-by:
Daniel Vetter <daniel.vetter@ffwll.ch>
5fb9dadf