Revert "drm/i915: Add DSC support to MST path"

This reverts commit e1a84ba8.

Part of a series where patches were modified while applying to resolve
conflicts, leading to further conflicts between drm-misc-next and
drm-intel-next, resulting in build failures in drm-tip. To be applied
again on a baseline with drm-misc-next and drm-intel-next in sync.
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

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

@@ -116,6 +116,7 @@ bool intel_dp_is_edp(struct intel_dp *intel_dp)
 }
 
 static void intel_dp_unset_edid(struct intel_dp *intel_dp);
+static int intel_dp_dsc_compute_bpp(struct intel_dp *intel_dp, u8 dsc_max_bpc);
 
 /* Is link rate UHBR and thus 128b/132b? */
 bool intel_dp_is_uhbr(const struct intel_crtc_state *crtc_state)
@@ -671,12 +672,11 @@ small_joiner_ram_size_bits(struct drm_i915_private *i915)
 		return 6144 * 8;
 }
 
-u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
-				u32 link_clock, u32 lane_count,
-				u32 mode_clock, u32 mode_hdisplay,
-				bool bigjoiner,
-				u32 pipe_bpp,
-				u32 timeslots)
+static u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
+				       u32 link_clock, u32 lane_count,
+				       u32 mode_clock, u32 mode_hdisplay,
+				       bool bigjoiner,
+				       u32 pipe_bpp)
 {
 	u32 bits_per_pixel, max_bpp_small_joiner_ram;
 	int i;
@@ -687,9 +687,8 @@ u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
 	 * for SST -> TimeSlotsPerMTP is 1,
 	 * for MST -> TimeSlotsPerMTP has to be calculated
 	 */
-	bits_per_pixel = (link_clock * lane_count * 8) * timeslots /
+	bits_per_pixel = (link_clock * lane_count * 8) /
 			 intel_dp_mode_to_fec_clock(mode_clock);
-	drm_dbg_kms(&i915->drm, "Max link bpp: %u\n", bits_per_pixel);
 
 	/* Small Joiner Check: output bpp <= joiner RAM (bits) / Horiz. width */
 	max_bpp_small_joiner_ram = small_joiner_ram_size_bits(i915) /
@@ -738,9 +737,9 @@ u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
 	return bits_per_pixel << 4;
 }
 
-u8 intel_dp_dsc_get_slice_count(struct intel_dp *intel_dp,
-				int mode_clock, int mode_hdisplay,
-				bool bigjoiner)
+static u8 intel_dp_dsc_get_slice_count(struct intel_dp *intel_dp,
+				       int mode_clock, int mode_hdisplay,
+				       bool bigjoiner)
 {
 	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 	u8 min_slice_count, i;
@@ -947,8 +946,8 @@ intel_dp_mode_valid_downstream(struct intel_connector *connector,
 	return MODE_OK;
 }
 
-bool intel_dp_need_bigjoiner(struct intel_dp *intel_dp,
-			     int hdisplay, int clock)
+static bool intel_dp_need_bigjoiner(struct intel_dp *intel_dp,
+				    int hdisplay, int clock)
 {
 	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 
@@ -1035,7 +1034,7 @@ intel_dp_mode_valid(struct drm_connector *_connector,
 							    target_clock,
 							    mode->hdisplay,
 							    bigjoiner,
-							    pipe_bpp, 1) >> 4;
+							    pipe_bpp) >> 4;
 			dsc_slice_count =
 				intel_dp_dsc_get_slice_count(intel_dp,
 							     target_clock,
@@ -1340,7 +1339,7 @@ intel_dp_compute_link_config_wide(struct intel_dp *intel_dp,
 	return -EINVAL;
 }
 
-int intel_dp_dsc_compute_bpp(struct intel_dp *intel_dp, u8 max_req_bpc)
+static int intel_dp_dsc_compute_bpp(struct intel_dp *intel_dp, u8 max_req_bpc)
 {
 	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 	int i, num_bpc;
@@ -1440,11 +1439,10 @@ static int intel_dp_dsc_compute_params(struct intel_encoder *encoder,
 	return drm_dsc_compute_rc_parameters(vdsc_cfg);
 }
 
-int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
-				struct intel_crtc_state *pipe_config,
-				struct drm_connector_state *conn_state,
-				struct link_config_limits *limits,
-				int timeslots)
+static int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
+				       struct intel_crtc_state *pipe_config,
+				       struct drm_connector_state *conn_state,
+				       struct link_config_limits *limits)
 {
 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
@@ -1495,8 +1493,7 @@ int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
 						    adjusted_mode->crtc_clock,
 						    adjusted_mode->crtc_hdisplay,
 						    pipe_config->bigjoiner_pipes,
-						    pipe_bpp,
-						    timeslots);
+						    pipe_bpp);
 		dsc_dp_slice_count =
 			intel_dp_dsc_get_slice_count(intel_dp,
 						     adjusted_mode->crtc_clock,
@@ -1508,13 +1505,27 @@ int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
 			return -EINVAL;
 		}
 		pipe_config->dsc.compressed_bpp = min_t(u16,
-							dsc_max_output_bpp >> 4,
-							pipe_config->pipe_bpp);
+							       dsc_max_output_bpp >> 4,
+							       pipe_config->pipe_bpp);
 		pipe_config->dsc.slice_count = dsc_dp_slice_count;
-		drm_dbg_kms(&dev_priv->drm, "DSC: compressed bpp %d slice count %d\n",
-			    pipe_config->dsc.compressed_bpp,
-			    pipe_config->dsc.slice_count);
 	}
+
+	/* As of today we support DSC for only RGB */
+	if (intel_dp->force_dsc_bpp) {
+		if (intel_dp->force_dsc_bpp >= 8 &&
+		    intel_dp->force_dsc_bpp < pipe_bpp) {
+			drm_dbg_kms(&dev_priv->drm,
+				    "DSC BPP forced to %d",
+				    intel_dp->force_dsc_bpp);
+			pipe_config->dsc.compressed_bpp =
+						intel_dp->force_dsc_bpp;
+		} else {
+			drm_dbg_kms(&dev_priv->drm,
+				    "Invalid DSC BPP %d",
+				    intel_dp->force_dsc_bpp);
+		}
+	}
+
 	/*
 	 * VDSC engine operates at 1 Pixel per clock, so if peak pixel rate
 	 * is greater than the maximum Cdclock and if slice count is even
@@ -1522,13 +1533,13 @@ int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
 	 */
 	if (adjusted_mode->crtc_clock > dev_priv->display.cdclk.max_cdclk_freq ||
 	    pipe_config->bigjoiner_pipes) {
-		if (pipe_config->dsc.slice_count > 1) {
-			pipe_config->dsc.dsc_split = true;
-		} else {
+		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;
 	}
 
 	ret = intel_dp_dsc_compute_params(&dig_port->base, pipe_config);
@@ -1617,7 +1628,7 @@ intel_dp_compute_link_config(struct intel_encoder *encoder,
 			    str_yes_no(ret), str_yes_no(joiner_needs_dsc),
 			    str_yes_no(intel_dp->force_dsc_en));
 		ret = intel_dp_dsc_compute_config(intel_dp, pipe_config,
-						  conn_state, &limits, 1);
+						  conn_state, &limits);
 		if (ret < 0)
 			return ret;
 	}

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

@@ -56,11 +56,6 @@ void intel_dp_encoder_flush_work(struct drm_encoder *encoder);
 int intel_dp_compute_config(struct intel_encoder *encoder,
 			    struct intel_crtc_state *pipe_config,
 			    struct drm_connector_state *conn_state);
-int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
-				struct intel_crtc_state *pipe_config,
-				struct drm_connector_state *conn_state,
-				struct link_config_limits *limits,
-				int timeslots);
 bool intel_dp_is_edp(struct intel_dp *intel_dp);
 bool intel_dp_is_uhbr(const struct intel_crtc_state *crtc_state);
 bool intel_dp_is_port_edp(struct drm_i915_private *dev_priv, enum port port);
@@ -101,18 +96,6 @@ void intel_read_dp_sdp(struct intel_encoder *encoder,
 		       struct intel_crtc_state *crtc_state,
 		       unsigned int type);
 bool intel_digital_port_connected(struct intel_encoder *encoder);
-int intel_dp_dsc_compute_bpp(struct intel_dp *intel_dp, u8 dsc_max_bpc);
-u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
-				u32 link_clock, u32 lane_count,
-				u32 mode_clock, u32 mode_hdisplay,
-				bool bigjoiner,
-				u32 pipe_bpp,
-				u32 timeslots);
-u8 intel_dp_dsc_get_slice_count(struct intel_dp *intel_dp,
-				int mode_clock, int mode_hdisplay,
-				bool bigjoiner);
-bool intel_dp_need_bigjoiner(struct intel_dp *intel_dp,
-			     int hdisplay, int clock);
 
 static inline unsigned int intel_dp_unused_lane_mask(int lane_count)
 {

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

@@ -139,63 +139,6 @@ static int intel_dp_mst_compute_link_config(struct intel_encoder *encoder,
 	return 0;
 }
 
-static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
-						struct intel_crtc_state *crtc_state,
-						struct drm_connector_state *conn_state,
-						struct link_config_limits *limits)
-{
-	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(encoder);
-	struct intel_dp *intel_dp = &intel_mst->primary->dp;
-	struct intel_connector *connector =
-		to_intel_connector(conn_state->connector);
-	struct drm_i915_private *i915 = to_i915(connector->base.dev);
-	const struct drm_display_mode *adjusted_mode =
-		&crtc_state->hw.adjusted_mode;
-	bool constant_n = drm_dp_has_quirk(&intel_dp->desc,
-					   DP_DPCD_QUIRK_CONSTANT_N);
-	int slots = -EINVAL;
-	int i, num_bpc;
-	u8 dsc_bpc[3] = {0};
-	int min_bpp, max_bpp;
-	u8 dsc_max_bpc;
-
-	/* Max DSC Input BPC for ICL is 10 and for TGL+ is 12 */
-	if (DISPLAY_VER(i915) >= 12)
-		dsc_max_bpc = min_t(u8, 12, conn_state->max_requested_bpc);
-	else
-		dsc_max_bpc = min_t(u8, 10, conn_state->max_requested_bpc);
-
-	max_bpp = min_t(u8, dsc_max_bpc * 3, limits->max_bpp);
-	min_bpp = limits->min_bpp;
-
-	num_bpc = drm_dp_dsc_sink_supported_input_bpcs(intel_dp->dsc_dpcd,
-						       dsc_bpc);
-	for (i = 0; i < num_bpc; i++) {
-		if (max_bpp >= dsc_bpc[i] * 3)
-			if (min_bpp > dsc_bpc[i] * 3)
-				min_bpp = dsc_bpc[i] * 3;
-	}
-
-	drm_dbg_kms(&i915->drm, "DSC Sink supported min bpp %d max bpp %d\n",
-		    min_bpp, max_bpp);
-
-	slots = intel_dp_mst_find_vcpi_slots_for_bpp(encoder, crtc_state, max_bpp,
-						     min_bpp, limits,
-						     conn_state, 2 * 3, true);
-
-	if (slots < 0)
-		return slots;
-
-	intel_link_compute_m_n(crtc_state->pipe_bpp,
-			       crtc_state->lane_count,
-			       adjusted_mode->crtc_clock,
-			       crtc_state->port_clock,
-			       &crtc_state->dp_m_n,
-			       constant_n, crtc_state->fec_enable);
-	crtc_state->dp_m_n.tu = slots;
-
-	return 0;
-}
 static int intel_dp_mst_update_slots(struct intel_encoder *encoder,
 				     struct intel_crtc_state *crtc_state,
 				     struct drm_connector_state *conn_state)
@@ -272,29 +215,6 @@ static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
 
 	ret = intel_dp_mst_compute_link_config(encoder, pipe_config,
 					       conn_state, &limits);
-
-	if (ret == -EDEADLK)
-		return ret;
-
-	/* enable compression if the mode doesn't fit available BW */
-	drm_dbg_kms(&dev_priv->drm, "Force DSC en = %d\n", intel_dp->force_dsc_en);
-	if (ret || intel_dp->force_dsc_en) {
-		/*
-		 * Try to get at least some timeslots and then see, if
-		 * we can fit there with DSC.
-		 */
-		drm_dbg_kms(&dev_priv->drm, "Trying to find VCPI slots in DSC mode\n");
-
-		ret = intel_dp_dsc_mst_compute_link_config(encoder, pipe_config,
-							   conn_state, &limits);
-		if (ret < 0)
-			return ret;
-
-		ret = intel_dp_dsc_compute_config(intel_dp, pipe_config,
-						  conn_state, &limits,
-						  pipe_config->dp_m_n.tu);
-	}
-
 	if (ret)
 		return ret;
 
@@ -833,10 +753,6 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
 	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
 	int max_rate, mode_rate, max_lanes, max_link_clock;
 	int ret;
-	bool dsc = false, bigjoiner = false;
-	u16 dsc_max_output_bpp = 0;
-	u8 dsc_slice_count = 0;
-	int target_clock = mode->clock;
 
 	if (drm_connector_is_unregistered(connector)) {
 		*status = MODE_ERROR;
@@ -874,48 +790,6 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
 		return 0;
 	}
 
-	if (intel_dp_need_bigjoiner(intel_dp, mode->hdisplay, target_clock)) {
-		bigjoiner = true;
-		max_dotclk *= 2;
-	}
-
-	if (DISPLAY_VER(dev_priv) >= 10 &&
-	    drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd)) {
-		/*
-		 * TBD pass the connector BPC,
-		 * for now U8_MAX so that max BPC on that platform would be picked
-		 */
-		int pipe_bpp = intel_dp_dsc_compute_bpp(intel_dp, U8_MAX);
-
-		if (drm_dp_sink_supports_fec(intel_dp->fec_capable)) {
-			dsc_max_output_bpp =
-				intel_dp_dsc_get_output_bpp(dev_priv,
-							    max_link_clock,
-							    max_lanes,
-							    target_clock,
-							    mode->hdisplay,
-							    bigjoiner,
-							    pipe_bpp, 1) >> 4;
-			dsc_slice_count =
-				intel_dp_dsc_get_slice_count(intel_dp,
-							     target_clock,
-							     mode->hdisplay,
-							     bigjoiner);
-		}
-
-		dsc = dsc_max_output_bpp && dsc_slice_count;
-	}
-
-	/*
-	 * Big joiner configuration needs DSC for TGL which is not true for
-	 * XE_LPD where uncompressed joiner is supported.
-	 */
-	if (DISPLAY_VER(dev_priv) < 13 && bigjoiner && !dsc)
-		return MODE_CLOCK_HIGH;
-
-	if (mode_rate > max_rate && !dsc)
-		return MODE_CLOCK_HIGH;
-
 	*status = intel_mode_valid_max_plane_size(dev_priv, mode, false);
 	return 0;
 }