Re: [PATCH 3/4] drm/i915: Compute config and mode valid changes for ultrajoiner

["Nautiyal, Ankit K" <ankit.k.nautiyal@xxxxxxxxx>]

On 6/26/2024 1:48 PM, Stanislav Lisovskiy wrote:
> Implement required changes for mode validation and compute config,
> to support Ultrajoiner.
> This also includes required DSC changes and checks.
>
> Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
> ---
>   drivers/gpu/drm/i915/display/intel_display.c |   5 +-
>   drivers/gpu/drm/i915/display/intel_display.h |   3 +-
>   drivers/gpu/drm/i915/display/intel_dp.c      | 117 ++++++++++++++-----
>   drivers/gpu/drm/i915/display/intel_dp.h      |  18 ++-
>   drivers/gpu/drm/i915/display/intel_dp_mst.c  |  35 +++---
>   drivers/gpu/drm/i915/display/intel_dsi.c     |   2 +-
>   drivers/gpu/drm/i915/display/intel_hdmi.c    |  14 ++-
>   drivers/gpu/drm/i915/display/intel_vdsc.c    |  25 +++-
>   8 files changed, 164 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index f702ead9b5f3..4c934f07ead7 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -8246,7 +8246,8 @@ enum drm_mode_status intel_cpu_transcoder_mode_valid(struct drm_i915_private *de
>   enum drm_mode_status
>   intel_mode_valid_max_plane_size(struct drm_i915_private *dev_priv,
>   				const struct drm_display_mode *mode,
> -				bool joiner)
> +				bool bigjoiner,
> +				bool ultrajoiner)
>   {
>   	int plane_width_max, plane_height_max;
>   
> @@ -8263,7 +8264,7 @@ intel_mode_valid_max_plane_size(struct drm_i915_private *dev_priv,
>   	 * too big for that.
>   	 */
>   	if (DISPLAY_VER(dev_priv) >= 11) {
> -		plane_width_max = 5120 << joiner;
> +		plane_width_max = (5120 << bigjoiner) << ultrajoiner;
>   		plane_height_max = 4320;
>   	} else {
>   		plane_width_max = 5120;
> diff --git a/drivers/gpu/drm/i915/display/intel_display.h b/drivers/gpu/drm/i915/display/intel_display.h
> index bac81b7ab764..0a51f24af405 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.h
> +++ b/drivers/gpu/drm/i915/display/intel_display.h
> @@ -415,7 +415,8 @@ u32 intel_plane_fb_max_stride(struct drm_i915_private *dev_priv,
>   enum drm_mode_status
>   intel_mode_valid_max_plane_size(struct drm_i915_private *dev_priv,
>   				const struct drm_display_mode *mode,
> -				bool joiner);
> +				bool bigjoiner,
> +				bool ultrajoiner);
>   enum drm_mode_status
>   intel_cpu_transcoder_mode_valid(struct drm_i915_private *i915,
>   				const struct drm_display_mode *mode);
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 3903f6ead6e6..1ea1e89d8f45 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -760,33 +760,41 @@ u32 intel_dp_dsc_nearest_valid_bpp(struct drm_i915_private *i915, u32 bpp, u32 p
>   static
>   u32 get_max_compressed_bpp_with_joiner(struct drm_i915_private *i915,
>   				       u32 mode_clock, u32 mode_hdisplay,
> -				       bool bigjoiner)
> +				       bool bigjoiner, bool ultrajoiner)
>   {
>   	u32 max_bpp_small_joiner_ram;
> +	u32 max_bpp_joiner;
>   
>   	/* Small Joiner Check: output bpp <= joiner RAM (bits) / Horiz. width */
> -	max_bpp_small_joiner_ram = small_joiner_ram_size_bits(i915) / mode_hdisplay;
> +	max_bpp_joiner = max_bpp_small_joiner_ram =
> +		small_joiner_ram_size_bits(i915) / mode_hdisplay;
>   
> -	if (bigjoiner) {
> -		int bigjoiner_interface_bits = DISPLAY_VER(i915) >= 14 ? 36 : 24;
> -		/* With bigjoiner multiple dsc engines are used in parallel so PPC is 2 */
> +	/* if ultra joiner is enabled, we have 2 bigjoiners enabled */
> +	if (bigjoiner || ultrajoiner) {
> +		int joiner_interface_bits = DISPLAY_VER(i915) >= 14 ? 36 : 24;
> +		/* With joiner multiple dsc engines are used in parallel so PPC is 2 */
>   		int ppc = 2;
> -		u32 max_bpp_bigjoiner =
> -			i915->display.cdclk.max_cdclk_freq * ppc * bigjoiner_interface_bits /
> +		max_bpp_joiner =
> +			i915->display.cdclk.max_cdclk_freq * ppc * joiner_interface_bits /
>   			intel_dp_mode_to_fec_clock(mode_clock);
>   
>   		max_bpp_small_joiner_ram *= 2;
> +	}
>   
> -		return min(max_bpp_small_joiner_ram, max_bpp_bigjoiner);
> +	if (ultrajoiner) {
> +		/* both get multiplied by 2, because ram bits/ppc now doubled */
> +		max_bpp_small_joiner_ram *= 2;
> +		max_bpp_joiner *= 2;
>   	}
>   
> -	return max_bpp_small_joiner_ram;
> +	return min(max_bpp_small_joiner_ram, max_bpp_joiner);
>   }
>   
>   u16 intel_dp_dsc_get_max_compressed_bpp(struct drm_i915_private *i915,
>   					u32 link_clock, u32 lane_count,
>   					u32 mode_clock, u32 mode_hdisplay,
>   					bool bigjoiner,
> +					bool ultrajoiner,
>   					enum intel_output_format output_format,
>   					u32 pipe_bpp,
>   					u32 timeslots)
> @@ -832,7 +840,7 @@ u16 intel_dp_dsc_get_max_compressed_bpp(struct drm_i915_private *i915,
>   				intel_dp_mode_to_fec_clock(mode_clock));
>   
>   	joiner_max_bpp = get_max_compressed_bpp_with_joiner(i915, mode_clock,
> -							    mode_hdisplay, bigjoiner);
> +							    mode_hdisplay, bigjoiner, ultrajoiner);
>   	bits_per_pixel = min(bits_per_pixel, joiner_max_bpp);
>   
>   	bits_per_pixel = intel_dp_dsc_nearest_valid_bpp(i915, bits_per_pixel, pipe_bpp);
> @@ -842,7 +850,8 @@ u16 intel_dp_dsc_get_max_compressed_bpp(struct drm_i915_private *i915,
>   
>   u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector,
>   				int mode_clock, int mode_hdisplay,
> -				bool bigjoiner)
> +				bool bigjoiner,
> +				bool ultrajoiner)
>   {
>   	struct drm_i915_private *i915 = to_i915(connector->base.dev);
>   	u8 min_slice_count, i;
> @@ -876,7 +885,7 @@ u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector,
>   
>   	/* Find the closest match to the valid slice count values */
>   	for (i = 0; i < ARRAY_SIZE(valid_dsc_slicecount); i++) {
> -		u8 test_slice_count = valid_dsc_slicecount[i] << bigjoiner;
> +		u8 test_slice_count = (valid_dsc_slicecount[i] << bigjoiner) << ultrajoiner;
>   
>   		if (test_slice_count >
>   		    drm_dp_dsc_sink_max_slice_count(connector->dp.dsc_dpcd, false))
> @@ -886,6 +895,10 @@ u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector,
>   		if (bigjoiner && test_slice_count < 4)
>   			continue;
>   
> +		/* ultrajoiner needs 2 bigjoiners to be enabled */
> +		if (ultrajoiner && test_slice_count < 8)
> +			continue;
> +
>   		if (min_slice_count <= test_slice_count)
>   			return test_slice_count;
>   	}
> @@ -1162,9 +1175,9 @@ intel_dp_mode_valid_downstream(struct intel_connector *connector,
>   	return MODE_OK;
>   }
>   
> -bool intel_dp_need_joiner(struct intel_dp *intel_dp,
> -			  struct intel_connector *connector,
> -			  int hdisplay, int clock)
> +bool intel_dp_need_bigjoiner(struct intel_dp *intel_dp,
> +			     struct intel_connector *connector,
> +			     int hdisplay, int clock)
>   {
>   	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
>   
> @@ -1195,6 +1208,35 @@ bool intel_dp_has_dsc(const struct intel_connector *connector)
>   	return true;
>   }
>   
> +static
> +bool intel_can_ultrajoiner(const struct intel_encoder *encoder)
> +{
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> +
> +	return IS_DGFX(i915) && DISPLAY_VER(i915) >= 14;
> +}
> +
> +bool intel_dp_need_ultrajoiner(struct intel_dp *dp, int clock)
> +{
> +	const struct intel_encoder *encoder = &dp_to_dig_port(dp)->base;
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> +
> +	if (!intel_can_ultrajoiner(encoder))
> +		return false;
> +
> +	return clock > (i915->display.cdclk.max_dotclk_freq * 2);
> +}
> +
> +bool intel_is_bigjoiner(const struct intel_crtc_state *pipe_config)
> +{
> +	return hweight8(pipe_config->joiner_pipes) == 2;
> +}
> +
> +bool intel_is_ultrajoiner(const struct intel_crtc_state *pipe_config)
> +{
> +	return hweight8(pipe_config->joiner_pipes) == 4;
> +}
> +
>   static enum drm_mode_status
>   intel_dp_mode_valid(struct drm_connector *_connector,
>   		    struct drm_display_mode *mode)
> @@ -1209,7 +1251,7 @@ intel_dp_mode_valid(struct drm_connector *_connector,
>   	u16 dsc_max_compressed_bpp = 0;
>   	u8 dsc_slice_count = 0;
>   	enum drm_mode_status status;
> -	bool dsc = false, joiner = false;
> +	bool dsc = false, bigjoiner = false, ultrajoiner = false;
>   
>   	status = intel_cpu_transcoder_mode_valid(dev_priv, mode);
>   	if (status != MODE_OK)
> @@ -1230,11 +1272,16 @@ intel_dp_mode_valid(struct drm_connector *_connector,
>   		target_clock = fixed_mode->clock;
>   	}
>   
> -	if (intel_dp_need_joiner(intel_dp, connector,
> -				 mode->hdisplay, target_clock)) {
> -		joiner = true;
> +	if (intel_dp_need_ultrajoiner(intel_dp, target_clock)) {
> +		ultrajoiner = true;
> +		max_dotclk *= 4;
> +	}
> +	else if (intel_dp_need_bigjoiner(intel_dp, connector,
> +				    mode->hdisplay, target_clock)) {
> +		bigjoiner = true;
>   		max_dotclk *= 2;
>   	}
> +
>   	if (target_clock > max_dotclk)
>   		return MODE_CLOCK_HIGH;
>   
> @@ -1278,20 +1325,22 @@ intel_dp_mode_valid(struct drm_connector *_connector,
>   								    max_lanes,
>   								    target_clock,
>   								    mode->hdisplay,
> -								    joiner,
> +								    bigjoiner,
> +								    ultrajoiner,
>   								    output_format,
>   								    pipe_bpp, 64);
>   			dsc_slice_count =
>   				intel_dp_dsc_get_slice_count(connector,
>   							     target_clock,
>   							     mode->hdisplay,
> -							     joiner);
> +							     bigjoiner,
> +							     ultrajoiner);
>   		}
>   
>   		dsc = dsc_max_compressed_bpp && dsc_slice_count;
>   	}
>   
> -	if (intel_dp_joiner_needs_dsc(dev_priv, joiner) && !dsc)
> +	if (intel_dp_joiner_needs_dsc(dev_priv, bigjoiner, ultrajoiner) && !dsc)
>   		return MODE_CLOCK_HIGH;
>   
>   	if (mode_rate > max_rate && !dsc)
> @@ -1301,7 +1350,7 @@ intel_dp_mode_valid(struct drm_connector *_connector,
>   	if (status != MODE_OK)
>   		return status;
>   
> -	return intel_mode_valid_max_plane_size(dev_priv, mode, joiner);
> +	return intel_mode_valid_max_plane_size(dev_priv, mode, bigjoiner, ultrajoiner);
>   }
>   
>   bool intel_dp_source_supports_tps3(struct drm_i915_private *i915)
> @@ -2015,7 +2064,8 @@ static int dsc_compute_compressed_bpp(struct intel_dp *intel_dp,
>   
>   	dsc_joiner_max_bpp = get_max_compressed_bpp_with_joiner(i915, adjusted_mode->clock,
>   								adjusted_mode->hdisplay,
> -								pipe_config->joiner_pipes);
> +								intel_is_bigjoiner(pipe_config),
> +								intel_is_ultrajoiner(pipe_config));
>   	dsc_max_bpp = min(dsc_max_bpp, dsc_joiner_max_bpp);
>   	dsc_max_bpp = min(dsc_max_bpp, to_bpp_int(limits->link.max_bpp_x16));
>   
> @@ -2249,7 +2299,8 @@ int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
>   			intel_dp_dsc_get_slice_count(connector,
>   						     adjusted_mode->crtc_clock,
>   						     adjusted_mode->crtc_hdisplay,
> -						     pipe_config->joiner_pipes);
> +						     intel_is_bigjoiner(pipe_config),
> +						     intel_is_ultrajoiner(pipe_config));
>   		if (!dsc_dp_slice_count) {
>   			drm_dbg_kms(&dev_priv->drm,
>   				    "Compressed Slice Count not supported\n");
> @@ -2399,14 +2450,15 @@ int intel_dp_config_required_rate(const struct intel_crtc_state *crtc_state)
>   	return intel_dp_link_required(adjusted_mode->crtc_clock, bpp);
>   }
>   
> -bool intel_dp_joiner_needs_dsc(struct drm_i915_private *i915, bool use_joiner)
> +bool intel_dp_joiner_needs_dsc(struct drm_i915_private *i915, bool bigjoiner, bool ultrajoiner)
>   {
>   	/*
>   	 * 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 DISPLAY_VER(i915) < 13 && use_joiner;
> +	return (DISPLAY_VER(i915) < 13 && bigjoiner) || ultrajoiner;
>   }
>   
>   static int
> @@ -2424,18 +2476,21 @@ intel_dp_compute_link_config(struct intel_encoder *encoder,
>   	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
>   	struct link_config_limits limits;
>   	bool dsc_needed, joiner_needs_dsc;
> +	bool bigjoiner = false, ultrajoiner = false;
>   	int ret = 0;
>   
>   	if (pipe_config->fec_enable &&
>   	    !intel_dp_supports_fec(intel_dp, connector, pipe_config))
>   		return -EINVAL;
>   
> -	if (intel_dp_need_joiner(intel_dp, connector,
> -				 adjusted_mode->crtc_hdisplay,
> -				 adjusted_mode->crtc_clock))
> +	if (intel_dp_need_ultrajoiner(intel_dp, adjusted_mode->crtc_clock))
> +		pipe_config->joiner_pipes = GENMASK(crtc->pipe + 3, crtc->pipe);
> +	else if (intel_dp_need_bigjoiner(intel_dp, connector,
> +					 adjusted_mode->crtc_hdisplay,
> +					 adjusted_mode->crtc_clock))
>   		pipe_config->joiner_pipes = GENMASK(crtc->pipe + 1, crtc->pipe);
>   
> -	joiner_needs_dsc = intel_dp_joiner_needs_dsc(i915, pipe_config->joiner_pipes);
> +	joiner_needs_dsc = intel_dp_joiner_needs_dsc(i915, bigjoiner, ultrajoiner);
>   
>   	dsc_needed = joiner_needs_dsc || intel_dp->force_dsc_en ||
>   		     !intel_dp_compute_config_limits(intel_dp, pipe_config,
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
> index a0f990a95ecc..6a3615757c95 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.h
> +++ b/drivers/gpu/drm/i915/display/intel_dp.h
> @@ -122,7 +122,7 @@ int intel_dp_effective_data_rate(int pixel_clock, int bpp_x16,
>   				 int bw_overhead);
>   int intel_dp_max_link_data_rate(struct intel_dp *intel_dp,
>   				int max_dprx_rate, int max_dprx_lanes);
> -bool intel_dp_joiner_needs_dsc(struct drm_i915_private *i915, bool use_joiner);
> +bool intel_dp_joiner_needs_dsc(struct drm_i915_private *i915, bool use_bigjoiner, bool use_ultrajoiner);
>   bool intel_dp_has_joiner(struct intel_dp *intel_dp);
>   bool intel_dp_needs_vsc_sdp(const struct intel_crtc_state *crtc_state,
>   			    const struct drm_connector_state *conn_state);
> @@ -142,6 +142,7 @@ u16 intel_dp_dsc_get_max_compressed_bpp(struct drm_i915_private *i915,
>   					u32 link_clock, u32 lane_count,
>   					u32 mode_clock, u32 mode_hdisplay,
>   					bool bigjoiner,
> +					bool ultrajoiner,
>   					enum intel_output_format output_format,
>   					u32 pipe_bpp,
>   					u32 timeslots);
> @@ -151,10 +152,17 @@ int intel_dp_dsc_sink_max_compressed_bpp(const struct intel_connector *connector
>   					 int bpc);
>   u8 intel_dp_dsc_get_slice_count(const struct intel_connector *connector,
>   				int mode_clock, int mode_hdisplay,
> -				bool bigjoiner);
> -bool intel_dp_need_joiner(struct intel_dp *intel_dp,
> -			  struct intel_connector *connector,
> -			  int hdisplay, int clock);
> +				bool bigjoiner, bool ultrajoiner);
> +bool intel_dp_need_bigjoiner(struct intel_dp *intel_dp,
> +			     struct intel_connector *connector,
> +			     int hdisplay, int clock);
> +bool intel_dp_need_ultrajoiner(struct intel_dp *intel_dp, int clock);
> +bool intel_is_bigjoiner(const struct intel_crtc_state *pipe_config);
> +bool intel_is_ultrajoiner(const struct intel_crtc_state *pipe_config);
> +bool intel_crtc_is_bigjoiner_slave(const struct intel_crtc_state *crtc_state);
> +bool intel_crtc_is_bigjoiner_master(const struct intel_crtc_state *crtc_state);
> +bool intel_crtc_is_joiner_primary_master(const struct intel_crtc_state *crtc_state);
> +enum pipe intel_crtc_master_pipe(const struct intel_crtc_state *crtc_state);
>   
>   static inline unsigned int intel_dp_unused_lane_mask(int lane_count)
>   {
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 27ce5c3f5951..13828c011d9c 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -105,7 +105,8 @@ static int intel_dp_mst_bw_overhead(const struct intel_crtc_state *crtc_state,
>   		dsc_slice_count = intel_dp_dsc_get_slice_count(connector,
>   							       adjusted_mode->clock,
>   							       adjusted_mode->hdisplay,
> -							       crtc_state->joiner_pipes);
> +							       intel_is_bigjoiner(crtc_state),
> +							       intel_is_ultrajoiner(crtc_state));
>   	}
>   
>   	overhead = drm_dp_bw_overhead(crtc_state->lane_count,
> @@ -576,16 +577,19 @@ static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
>   	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
>   		return -EINVAL;
>   
> -	if (intel_dp_need_joiner(intel_dp, connector,
> -				 adjusted_mode->crtc_hdisplay,
> -				 adjusted_mode->crtc_clock))
> +	if (intel_dp_need_ultrajoiner(intel_dp, adjusted_mode->crtc_clock))
> +		pipe_config->joiner_pipes = GENMASK(crtc->pipe + 3, crtc->pipe);
> +	else if (intel_dp_need_bigjoiner(intel_dp, connector,
> +				    adjusted_mode->crtc_hdisplay,
> +				    adjusted_mode->crtc_clock))
>   		pipe_config->joiner_pipes = GENMASK(crtc->pipe + 1, crtc->pipe);
>   
>   	pipe_config->sink_format = INTEL_OUTPUT_FORMAT_RGB;
>   	pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;
>   	pipe_config->has_pch_encoder = false;
>   
> -	joiner_needs_dsc = intel_dp_joiner_needs_dsc(dev_priv, pipe_config->joiner_pipes);
> +	joiner_needs_dsc = intel_dp_joiner_needs_dsc(dev_priv, intel_is_bigjoiner(pipe_config),
> +						     intel_is_ultrajoiner(pipe_config));
>   
>   	dsc_needed = joiner_needs_dsc || intel_dp->force_dsc_en ||
>   		     !intel_dp_mst_compute_config_limits(intel_dp,
> @@ -1388,7 +1392,7 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>   	int max_dotclk = to_i915(connector->dev)->display.cdclk.max_dotclk_freq;
>   	int max_rate, mode_rate, max_lanes, max_link_clock;
>   	int ret;
> -	bool dsc = false, joiner = false;
> +	bool dsc = false, bigjoiner = false, ultrajoiner = false;
>   	u16 dsc_max_compressed_bpp = 0;
>   	u8 dsc_slice_count = 0;
>   	int target_clock = mode->clock;
> @@ -1431,9 +1435,12 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>   	 *   corresponding link capabilities of the sink) in case the
>   	 *   stream is uncompressed for it by the last branch device.
>   	 */
> -	if (intel_dp_need_joiner(intel_dp, intel_connector,
> -				 mode->hdisplay, target_clock)) {
> -		joiner = true;
> +	if (intel_dp_need_ultrajoiner(intel_dp, target_clock)) {
> +		ultrajoiner = true;
> +		max_dotclk *= 4;
> +	} else if (intel_dp_need_bigjoiner(intel_dp, intel_connector,
> +					   mode->hdisplay, target_clock)) {
> +		bigjoiner = true;
>   		max_dotclk *= 2;
>   	}
>   
> @@ -1461,20 +1468,22 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>   								    max_lanes,
>   								    target_clock,
>   								    mode->hdisplay,
> -								    joiner,
> +								    bigjoiner,
> +								    ultrajoiner,
>   								    INTEL_OUTPUT_FORMAT_RGB,
>   								    pipe_bpp, 64);
>   			dsc_slice_count =
>   				intel_dp_dsc_get_slice_count(intel_connector,
>   							     target_clock,
>   							     mode->hdisplay,
> -							     joiner);
> +							     bigjoiner,
> +							     ultrajoiner);
>   		}
>   
>   		dsc = dsc_max_compressed_bpp && dsc_slice_count;
>   	}
>   
> -	if (intel_dp_joiner_needs_dsc(dev_priv, joiner) && !dsc) {
> +	if (intel_dp_joiner_needs_dsc(dev_priv, bigjoiner, ultrajoiner) && !dsc) {
>   		*status = MODE_CLOCK_HIGH;
>   		return 0;
>   	}
> @@ -1484,7 +1493,7 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>   		return 0;
>   	}
>   
> -	*status = intel_mode_valid_max_plane_size(dev_priv, mode, joiner);
> +	*status = intel_mode_valid_max_plane_size(dev_priv, mode, bigjoiner, ultrajoiner);
>   	return 0;
>   }
>   
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi.c b/drivers/gpu/drm/i915/display/intel_dsi.c
> index bd5888ce4852..1a7e9a56fccd 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsi.c
> @@ -76,7 +76,7 @@ enum drm_mode_status intel_dsi_mode_valid(struct drm_connector *connector,
>   	if (fixed_mode->clock > max_dotclk)
>   		return MODE_CLOCK_HIGH;
>   
> -	return intel_mode_valid_max_plane_size(dev_priv, mode, false);
> +	return intel_mode_valid_max_plane_size(dev_priv, mode, false, false);
>   }
>   
>   struct intel_dsi_host *intel_dsi_host_init(struct intel_dsi *intel_dsi,
> diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c
> index 19498ee455fa..35be89050512 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdmi.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c
> @@ -2048,7 +2048,7 @@ intel_hdmi_mode_valid(struct drm_connector *connector,
>   			return status;
>   	}
>   
> -	return intel_mode_valid_max_plane_size(dev_priv, mode, false);
> +	return intel_mode_valid_max_plane_size(dev_priv, mode, false, false);
>   }
>   
>   bool intel_hdmi_bpc_possible(const struct intel_crtc_state *crtc_state,
> @@ -2341,6 +2341,18 @@ int intel_hdmi_compute_config(struct intel_encoder *encoder,
>   		return ret;
>   	}
>   
> +	if (adjusted_mode->crtc_clock > dev_priv->display.cdclk.max_dotclk_freq ||
> +	    pipe_config->joiner_pipes) {
> +		if (pipe_config->dsc.slice_count < 2) {
> +			drm_dbg_kms(&dev_priv->drm,
> +				    "Cannot split stream to use 2 VDSC instances\n");
> +			return -EINVAL;
> +		}
> +
> +		pipe_config->dsc.dsc_split = true;
> +	}
> +

I think we can skip the HDMI part, since we are not supporting 
bigjoiner/dsc yet.

Regards,

Ankit


> +
>   	if (intel_hdmi_is_ycbcr420(pipe_config)) {
>   		ret = intel_panel_fitting(pipe_config, conn_state);
>   		if (ret)
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 11058bb37d5a..206b3e77e0d5 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -13,6 +13,7 @@
>   #include "intel_crtc.h"
>   #include "intel_de.h"
>   #include "intel_display_types.h"
> +#include "intel_dp.h"
>   #include "intel_dsi.h"
>   #include "intel_qp_tables.h"
>   #include "intel_vdsc.h"
> @@ -379,7 +380,9 @@ int intel_dsc_get_num_vdsc_instances(const struct intel_crtc_state *crtc_state)
>   {
>   	int num_vdsc_instances = intel_dsc_get_vdsc_per_pipe(crtc_state);
>   
> -	if (crtc_state->joiner_pipes)
> +	if (intel_is_ultrajoiner(crtc_state))
> +		num_vdsc_instances *= 4;
> +	else if (intel_is_bigjoiner(crtc_state))
>   		num_vdsc_instances *= 2;
>   
>   	return num_vdsc_instances;
> @@ -770,6 +773,13 @@ void intel_uncompressed_joiner_enable(const struct intel_crtc_state *crtc_state)
>   	}
>   }
>   
> +static bool intel_crtc_ultrajoiner_enable_needed(const struct intel_crtc_state *crtc_state)
> +{
> +	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> +
> +	return intel_is_ultrajoiner(crtc_state) && crtc->pipe != PIPE_D;
> +}
> +
>   void intel_dsc_enable(const struct intel_crtc_state *crtc_state)
>   {
>   	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> @@ -788,8 +798,21 @@ void intel_dsc_enable(const struct intel_crtc_state *crtc_state)
>   		dss_ctl2_val |= RIGHT_BRANCH_VDSC_ENABLE;
>   		dss_ctl1_val |= JOINER_ENABLE;
>   	}
> +
>   	if (crtc_state->joiner_pipes) {
> +		/*
> +		 * This bit doesn't seem to follow master/slave logic or
> +		 * any other logic, so lets just add helper function to
> +		 * at least hide this hassle..
> +		 */
> +		if (intel_crtc_ultrajoiner_enable_needed(crtc_state))
> +			dss_ctl1_val |= ULTRA_JOINER_ENABLE;
> +
> +		if (intel_crtc_is_ultrajoiner_primary(crtc_state))
> +			dss_ctl1_val |= PRIMARY_ULTRA_JOINER_ENABLE;;
> +
>   		dss_ctl1_val |= BIG_JOINER_ENABLE;
> +
>   		if (intel_crtc_is_bigjoiner_primary(crtc_state))
>   			dss_ctl1_val |= PRIMARY_BIG_JOINER_ENABLE;
>   	}