Re: [PATCH 2/4] drm/i915/display: Use joined pipes in intel_dp_joiner_needs_dsc

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

On Thu, Sep 12, 2024 at 05:13:28PM +0530, Ankit Nautiyal wrote:
> In preparation of ultrajoiner, use number of joined pipes in the
> intel_dp_joiner_needs_dsc helper, instead of joiner flag.
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c     | 16 ++++++++++++----
>  drivers/gpu/drm/i915/display/intel_dp.h     |  3 ++-
>  drivers/gpu/drm/i915/display/intel_dp_mst.c | 10 ++++++++--
>  3 files changed, 22 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index cb0f6db5f8e7..f6900f1ff36f 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -1318,6 +1318,7 @@ intel_dp_mode_valid(struct drm_connector *_connector,
>  	u8 dsc_slice_count = 0;
>  	enum drm_mode_status status;
>  	bool dsc = false, joiner = false;
> +	int num_joined_pipes;
>  
>  	status = intel_cpu_transcoder_mode_valid(dev_priv, mode);
>  	if (status != MODE_OK)
> @@ -1343,6 +1344,9 @@ intel_dp_mode_valid(struct drm_connector *_connector,
>  		joiner = true;
>  		max_dotclk *= 2;
>  	}
> +
> +	num_joined_pipes = joiner ? 2 : 1;
> +
>  	if (target_clock > max_dotclk)
>  		return MODE_CLOCK_HIGH;
>  
> @@ -1399,7 +1403,7 @@ intel_dp_mode_valid(struct drm_connector *_connector,
>  		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, num_joined_pipes) && !dsc)
>  		return MODE_CLOCK_HIGH;
>  
>  	if (mode_rate > max_rate && !dsc)
> @@ -2513,14 +2517,15 @@ 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,
> +			       int num_joined_pipes)
>  {
>  	/*
>  	 * Pipe joiner needs compression up to display 12 due to bandwidth
>  	 * limitation. DG2 onwards pipe joiner can be enabled without
>  	 * compression.
>  	 */
> -	return DISPLAY_VER(i915) < 13 && use_joiner;
> +	return DISPLAY_VER(i915) < 13 && num_joined_pipes == 2;
>  }
>  
>  static int
> @@ -2538,6 +2543,7 @@ 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;
> +	int num_joined_pipes;
>  	int ret = 0;
>  
>  	if (pipe_config->fec_enable &&
> @@ -2549,7 +2555,9 @@ intel_dp_compute_link_config(struct intel_encoder *encoder,
>  				 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);
> +	num_joined_pipes = pipe_config->joiner_pipes ? 2 : 1;

This could use intel_crtc_num_joined_pipes() already.

> +
> +	joiner_needs_dsc = intel_dp_joiner_needs_dsc(i915, num_joined_pipes);
>  
>  	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 1b9aaddd8c35..3aef57dd463a 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.h
> +++ b/drivers/gpu/drm/i915/display/intel_dp.h
> @@ -123,7 +123,8 @@ 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,
> +			       int num_joined_pipes);
>  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);
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 15541932b809..1868747cfb12 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -568,6 +568,7 @@ static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
>  		&pipe_config->hw.adjusted_mode;
>  	struct link_config_limits limits;
>  	bool dsc_needed, joiner_needs_dsc;
> +	int num_joined_pipes;
>  	int ret = 0;
>  
>  	if (pipe_config->fec_enable &&
> @@ -582,11 +583,13 @@ static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
>  				 adjusted_mode->crtc_clock))
>  		pipe_config->joiner_pipes = GENMASK(crtc->pipe + 1, crtc->pipe);
>  
> +	num_joined_pipes = pipe_config->joiner_pipes ? 2 : 1;

same here

Otherwise lgtm.

> +
>  	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, num_joined_pipes);
>  
>  	dsc_needed = joiner_needs_dsc || intel_dp->force_dsc_en ||
>  		     !intel_dp_mst_compute_config_limits(intel_dp,
> @@ -1426,6 +1429,7 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>  	u16 dsc_max_compressed_bpp = 0;
>  	u8 dsc_slice_count = 0;
>  	int target_clock = mode->clock;
> +	int num_joined_pipes;
>  
>  	if (drm_connector_is_unregistered(connector)) {
>  		*status = MODE_ERROR;
> @@ -1471,6 +1475,8 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>  		max_dotclk *= 2;
>  	}
>  
> +	num_joined_pipes = joiner ? 2 : 1;
> +
>  	ret = drm_modeset_lock(&mgr->base.lock, ctx);
>  	if (ret)
>  		return ret;
> @@ -1508,7 +1514,7 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
>  		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, num_joined_pipes) && !dsc) {
>  		*status = MODE_CLOCK_HIGH;
>  		return 0;
>  	}
> -- 
> 2.45.2

-- 
Ville Syrjälä
Intel