Re: [Intel-gfx] [PATCH] drm/i915/display : Remove support for interlace mode

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Wed, Jun 14, 2023 at 09:37:49AM +0530, Ankit Nautiyal wrote:
> There are multiple panels with which Interlace mode is seen to cause
> flickering (interlacing artifacts) with different platforms.
> 
> The issue is seen with both HDMI, DP with CML, CFL, ICL, EHL with
> different display models from Acer, Benq, Dell etc.
> There are some models where the issue is not seen with same setup.
> 
> Due to this, cases where multiple display are configured in clone mode,
> sometimes interlaced mode gets picked up in one of the displays
> and flickers are seen.
> 
> Since its difficult to pin point if issue is due to the HW or due to
> panels, removing interlace mode for DP and HDMI till this is
> root caused.

I though people already confirmewd the problem on non-Intel hw?
So seems pretty clear that it's the displays themselves that are
garbage.

> 
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8395
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c   | 3 ---
>  drivers/gpu/drm/i915/display/intel_hdmi.c | 3 ---
>  2 files changed, 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index f4192fda1a76..78d8ceb590a3 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -5665,9 +5665,6 @@ intel_dp_init_connector(struct intel_digital_port *dig_port,
>  	drm_connector_init(dev, connector, &intel_dp_connector_funcs, type);
>  	drm_connector_helper_add(connector, &intel_dp_connector_helper_funcs);
>  
> -	if (!HAS_GMCH(dev_priv) && DISPLAY_VER(dev_priv) < 12)
> -		connector->interlace_allowed = true;
> -
>  	intel_connector->polled = DRM_CONNECTOR_POLL_HPD;
>  
>  	intel_dp_aux_init(intel_dp);
> diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c
> index 7ac5e6c5e00d..9b3ea307ef40 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdmi.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c
> @@ -2998,9 +2998,6 @@ void intel_hdmi_init_connector(struct intel_digital_port *dig_port,
>  				    ddc);
>  	drm_connector_helper_add(connector, &intel_hdmi_connector_helper_funcs);
>  
> -	if (DISPLAY_VER(dev_priv) < 12)
> -		connector->interlace_allowed = true;
> -
>  	connector->stereo_allowed = true;
>  
>  	if (DISPLAY_VER(dev_priv) >= 10)
> -- 
> 2.40.1

-- 
Ville Syrjälä
Intel