drm/i915/display: Compute AS SDP parameters

Add necessary function definitions to compute AS SDP data.
The new intel_dp_compute_as_sdp function computes AS SDP
values based on the display configuration, ensuring proper
handling of Variable Refresh Rate (VRR).

--v2:
- Added DP_SDP_ADAPTIVE_SYNC to infoframe_type_to_idx(). [Ankit]
- Separated patch for intel_read/write_dp_sdp. [Ankit]
- _HSW_VIDEO_DIP_ASYNC_DATA_A should be from ADL onward. [Ankit]
- Fixed indentation issues. [Ankit]

--v3:
- Added VIDEO_DIP_ENABLE_AS_HSW flag to intel_dp_set_infoframes.

--v4:
- Added HAS_VRR check before writing AS SDP.

--v5:
Added missed HAS_VRR check before reading AS SDP.

--v6:
- Used Adaptive Sync sink status as a check for read/write SDP. (Ankit)

--v7:
- Remove as_sdp_enable from crtc_state.
- Add a comment mentioning current support of
  DP_AS_SDP_AVT_FIXED_VTOTAL.
- Add state checker for AS_SDP infoframe enable.

--v8:
- Drop conn_state from intel_dp_compute_as_sdp, as not used.
- Remove fullstop in subject line.

--v9:
- Add vrr.enable instead of is_in_vrr_range.

--v10:
- remove vrefresh and connector, as they are no  longer required.
Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240322031157.3823909-7-mitulkumar.ajitkumar.golani@intel.com

drivers/gpu/drm/i915/display/intel_dp.c

@@ -2619,6 +2619,29 @@ static void intel_dp_compute_vsc_colorimetry(const struct intel_crtc_state *crtc
 	vsc->content_type = DP_CONTENT_TYPE_NOT_DEFINED;
 }
 
+static void intel_dp_compute_as_sdp(struct intel_dp *intel_dp,
+				    struct intel_crtc_state *crtc_state)
+{
+	struct drm_dp_as_sdp *as_sdp = &crtc_state->infoframes.as_sdp;
+	const struct drm_display_mode *adjusted_mode =
+		&crtc_state->hw.adjusted_mode;
+
+	if (!crtc_state->vrr.enable ||
+	    !intel_dp_as_sdp_supported(intel_dp))
+		return;
+
+	crtc_state->infoframes.enable |= intel_hdmi_infoframe_enable(DP_SDP_ADAPTIVE_SYNC);
+
+	/* Currently only DP_AS_SDP_AVT_FIXED_VTOTAL mode supported */
+	as_sdp->sdp_type = DP_SDP_ADAPTIVE_SYNC;
+	as_sdp->length = 0x9;
+	as_sdp->mode = DP_AS_SDP_AVT_FIXED_VTOTAL;
+	as_sdp->vtotal = adjusted_mode->vtotal;
+	as_sdp->target_rr = 0;
+	as_sdp->duration_incr_ms = 0;
+	as_sdp->duration_incr_ms = 0;
+}
+
 static void intel_dp_compute_vsc_sdp(struct intel_dp *intel_dp,
 				     struct intel_crtc_state *crtc_state,
 				     const struct drm_connector_state *conn_state)
@@ -2970,6 +2993,7 @@ intel_dp_compute_config(struct intel_encoder *encoder,
 		g4x_dp_set_clock(encoder, pipe_config);
 
 	intel_vrr_compute_config(pipe_config, conn_state);
+	intel_dp_compute_as_sdp(intel_dp, pipe_config);
 	intel_psr_compute_config(intel_dp, pipe_config, conn_state);
 	intel_dp_drrs_compute_config(connector, pipe_config, link_bpp_x16);
 	intel_dp_compute_vsc_sdp(intel_dp, pipe_config, conn_state);