Re: [PATCH 14/16] drm/i915: Compute config and mode valid changes for ultrajoiner

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

On Mon, Sep 23, 2024 at 11:43:34PM +0530, Ankit Nautiyal wrote:
> From: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
> 
> Implement required changes for mode validation and compute config,
> to support Ultrajoiner.
> 
> v2:
> -Drop changes for HDMI.
> -Separate out DSC changes into another patch.
> v3: Fix check in can_ultrajoiner. (Ankit)
> v4:
> -Unify helper to check joiner requirement. (Ville)
> -Split patches for ultrajoiner changes for max dsc slices and compressed
> bpp.(Ankit)
> 
> Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 26 +++++++++++++++++++------
>  1 file changed, 20 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 115d8468bb91..8e0cb6c77c64 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -1280,26 +1280,38 @@ intel_dp_mode_valid_downstream(struct intel_connector *connector,
>  }
>  
>  static
> -bool intel_dp_needs_bigjoiner(struct intel_dp *intel_dp,
> -			      struct intel_connector *connector,
> -			      int hdisplay, int clock)
> +bool intel_dp_needs_joiner(struct intel_dp *intel_dp,
> +			   struct intel_connector *connector,
> +			   int hdisplay, int clock,
> +			   int num_joined_pipes)
>  {
>  	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
>  
>  	if (!intel_dp_has_joiner(intel_dp))
>  		return false;
>  
> -	return clock > i915->display.cdclk.max_dotclk_freq || hdisplay > 5120;
> +	num_joined_pipes /= 2;
> +
> +	return clock > num_joined_pipes * i915->display.cdclk.max_dotclk_freq ||
> +	       hdisplay > 5120;

'num_joined_pipes * 5120'

With that
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

>  }
>  
>  int intel_dp_num_joined_pipes(struct intel_dp *intel_dp,
>  			      struct intel_connector *connector,
>  			      int hdisplay, int clock)
>  {
> +	struct intel_display *display = to_intel_display(intel_dp);
> +	struct drm_i915_private *i915 = to_i915(display->drm);
> +
>  	if (connector->force_joined_pipes)
>  		return connector->force_joined_pipes;
>  
> -	if (intel_dp_needs_bigjoiner(intel_dp, connector, hdisplay, clock))
> +	if (HAS_ULTRAJOINER(i915) &&
> +	    intel_dp_needs_joiner(intel_dp, connector, hdisplay, clock, 4))
> +		return 4;
> +
> +	if ((HAS_BIGJOINER(i915) || HAS_UNCOMPRESSED_JOINER(i915)) &&
> +	    intel_dp_needs_joiner(intel_dp, connector, hdisplay, clock, 2))
>  		return 2;
>  
>  	return 1;
> @@ -2505,8 +2517,10 @@ bool intel_dp_joiner_needs_dsc(struct drm_i915_private *i915,
>  	 * Pipe joiner needs compression up to display 12 due to bandwidth
>  	 * limitation. DG2 onwards pipe joiner can be enabled without
>  	 * compression.
> +	 * Ultrajoiner always needs compression.
>  	 */
> -	return !HAS_UNCOMPRESSED_JOINER(i915) && num_joined_pipes == 2;
> +	return (!HAS_UNCOMPRESSED_JOINER(i915) && num_joined_pipes == 2) ||
> +		num_joined_pipes == 4;
>  }
>  
>  static int
> -- 
> 2.45.2

-- 
Ville Syrjälä
Intel