Re: [Intel-gfx] [PATCH 3/4] drm/i915/mst: Reject modes that require the bigjoiner

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 27 Nov 2023, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> We have no bigjoiner support in the MST code, so .mode_valid()
> pretending otherwise is just going to result black screens for
> users. Reject any mode that needs the joiner.
>
> Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
> Fixes: d51f25eb479a ("drm/i915: Add DSC support to MST path")
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Reviewed-by: Jani Nikula <jani.nikula@intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 0680a42f7d2a..b665fe6ef871 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -1332,6 +1332,10 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>  	if (intel_dp_need_bigjoiner(intel_dp, mode->hdisplay, target_clock)) {
>  		bigjoiner = true;
>  		max_dotclk *= 2;
> +
> +		/* TODO: add support for bigjoiner */
> +		*status = MODE_CLOCK_HIGH;
> +		return 0;
>  	}
>  
>  	if (DISPLAY_VER(dev_priv) >= 10 &&

-- 
Jani Nikula, Intel