[PATCH 18/20] drm/i915: YCBCR 420 support for LSPCON

Shashank Sharma shashank.sharma at intel.com
Mon Jul 10 11:18:46 UTC 2017


LSPCON chips support YCBCR420 outputs. To be able to get
YCBCR420 output from LSPCON chip, the source should:
- Generate YCBCR444 HDMI output
- Set AVI infoframes for a YCBCR420 output.

LSPCON FW gets the information from AVI infoframes, and generates
YCBCR420 output from a YCBCR444 input. This patch adds the necessary
changes to drive YCBCR420 output from LSPCON based HDMI output.

Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Imre Deak <imre.deak at intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 10 +++++++---
 drivers/gpu/drm/i915/intel_dp.c      | 16 +++++++++++++++-
 drivers/gpu/drm/i915/intel_drv.h     | 20 +++++++++++++++++---
 drivers/gpu/drm/i915/intel_hdmi.c    |  7 +++++--
 drivers/gpu/drm/i915/intel_lspcon.c  | 17 +++++++++++++++++
 5 files changed, 61 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index c5ff568..c3c7b31 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8125,9 +8125,11 @@ static void haswell_set_pipemisc(struct drm_crtc *crtc)
 			val |= PIPEMISC_DITHER_ENABLE | PIPEMISC_DITHER_TYPE_SP;
 
 		if (config->ycbcr420) {
-			val |= PIPEMISC_OUTPUT_YCBCR |
-				PIPEMISC_YCBCR420_ENABLE |
-				PIPEMISC_YCBCR420_MODE_BLEND;
+			val |= PIPEMISC_OUTPUT_YCBCR;
+
+			if (!config->lspcon_active)
+				val |= PIPEMISC_YCBCR420_ENABLE |
+					PIPEMISC_YCBCR420_MODE_BLEND;
 		}
 
 		I915_WRITE(PIPEMISC(intel_crtc->pipe), val);
@@ -14205,11 +14207,13 @@ static void intel_setup_outputs(struct drm_i915_private *dev_priv)
 		 * DDI_BUF_CTL_A or SFUSE_STRAP registers, find another way to
 		 * detect the ports.
 		 */
+
 		intel_ddi_init(dev_priv, PORT_A);
 		intel_ddi_init(dev_priv, PORT_B);
 		intel_ddi_init(dev_priv, PORT_C);
 
 		intel_dsi_init(dev_priv);
+
 	} else if (HAS_DDI(dev_priv)) {
 		int found;
 
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 67bc8a7a..1690aa9 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1614,7 +1614,9 @@ intel_dp_compute_config(struct intel_encoder *encoder,
 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
 	struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 	struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
-	enum port port = dp_to_dig_port(intel_dp)->port;
+	struct intel_digital_port *dig_port = enc_to_dig_port(&encoder->base);
+	enum port port = dig_port->port;
+	struct intel_lspcon *lspcon = &dig_port->lspcon;
 	struct intel_crtc *intel_crtc = to_intel_crtc(pipe_config->base.crtc);
 	struct intel_connector *intel_connector = intel_dp->attached_connector;
 	struct intel_digital_connector_state *intel_conn_state =
@@ -1635,6 +1637,18 @@ intel_dp_compute_config(struct intel_encoder *encoder,
 	common_len = intel_dp_common_len_rate_limit(intel_dp,
 						    intel_dp->max_link_rate);
 
+	/* LSPCON needs special handling to drive YCBCR420 outputs */
+	if (lspcon->active) {
+		struct drm_connector *connector = &intel_connector->base;
+		int clock_8bpc = pipe_config->base.adjusted_mode.crtc_clock;
+		int clock_12bpc = clock_8bpc * 3 / 2;
+
+		pipe_config->lspcon_active = true;
+		pipe_config->ycbcr420 = lspcon_ycbcr420_config(connector,
+					     pipe_config, &clock_12bpc,
+					     &clock_8bpc);
+	}
+
 	/* No common link rates between source and sink */
 	WARN_ON(common_len <= 0);
 
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index ed04de9..40d56f2 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -790,6 +790,9 @@ struct intel_crtc_state {
 
 	/* HDMI output type */
 	bool ycbcr420;
+
+	/* LSPCON is active on port */
+	bool lspcon_active;
 };
 
 struct intel_crtc {
@@ -1205,6 +1208,12 @@ static inline struct intel_dp *enc_to_intel_dp(struct drm_encoder *encoder)
 	return &enc_to_dig_port(encoder)->dp;
 }
 
+static inline struct intel_lspcon *
+enc_to_intel_lspcon(struct drm_encoder *encoder)
+{
+	return &enc_to_dig_port(encoder)->lspcon;
+}
+
 static inline struct intel_digital_port *
 dp_to_dig_port(struct intel_dp *intel_dp)
 {
@@ -1675,14 +1684,16 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port,
 			       struct intel_connector *intel_connector);
 struct intel_hdmi *enc_to_intel_hdmi(struct drm_encoder *encoder);
 bool intel_hdmi_compute_config(struct intel_encoder *encoder,
-			       struct intel_crtc_state *pipe_config,
-			       struct drm_connector_state *conn_state);
+				struct intel_crtc_state *pipe_config,
+				struct drm_connector_state *conn_state);
 void intel_hdmi_handle_sink_scrambling(struct intel_encoder *intel_encoder,
 				       struct drm_connector *connector,
 				       bool high_tmds_clock_ratio,
 				       bool scrambling);
 void intel_dp_dual_mode_set_tmds_output(struct intel_hdmi *hdmi, bool enable);
-
+bool intel_hdmi_ycbcr420_config(struct drm_connector *connector,
+				struct intel_crtc_state *config,
+				int *clock_12bpc, int *clock_8bpc);
 
 /* intel_lvds.c */
 void intel_lvds_init(struct drm_i915_private *dev_priv);
@@ -2003,6 +2014,9 @@ void intel_color_load_luts(struct drm_crtc_state *crtc_state);
 bool lspcon_init(struct intel_digital_port *intel_dig_port);
 void lspcon_resume(struct intel_lspcon *lspcon);
 void lspcon_wait_pcon_mode(struct intel_lspcon *lspcon);
+bool lspcon_ycbcr420_config(struct drm_connector *connector,
+			    struct intel_crtc_state *config,
+			    int *clock_12bpc, int *clock_8bpc);
 
 /* intel_pipe_crc.c */
 int intel_pipe_crc_create(struct drm_minor *minor);
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index d1b1efc..a08ab99 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -1362,8 +1362,7 @@ static bool hdmi_12bpc_possible(struct intel_crtc_state *crtc_state,
 	return true;
 }
 
-static bool
-intel_hdmi_ycbcr420_config(struct drm_connector *connector,
+bool intel_hdmi_ycbcr420_config(struct drm_connector *connector,
 			       struct intel_crtc_state *config,
 			       int *clock_12bpc, int *clock_8bpc)
 {
@@ -1380,6 +1379,10 @@ intel_hdmi_ycbcr420_config(struct drm_connector *connector,
 	*clock_8bpc /= 2;
 	config->ycbcr420 = true;
 
+	/* LSPCON doesn't need scaler for YCBCR420 output */
+	if (config->lspcon_active)
+		return true;
+
 	/* YCBCR 420 output conversion needs a scaler */
 	if (skl_update_scaler_crtc_420_output(config)) {
 		DRM_ERROR("Scaler allocation for output failed\n");
diff --git a/drivers/gpu/drm/i915/intel_lspcon.c b/drivers/gpu/drm/i915/intel_lspcon.c
index a350d79..f611b6d 100644
--- a/drivers/gpu/drm/i915/intel_lspcon.c
+++ b/drivers/gpu/drm/i915/intel_lspcon.c
@@ -202,6 +202,21 @@ static void lspcon_resume_in_pcon_wa(struct intel_lspcon *lspcon)
 	DRM_DEBUG_KMS("LSPCON DP descriptor mismatch after resume\n");
 }
 
+bool lspcon_ycbcr420_config(struct drm_connector *connector,
+			    struct intel_crtc_state *config,
+			    int *clock_12bpc, int *clock_8bpc)
+{
+	struct drm_display_info *info = &connector->display_info;
+	struct drm_display_mode *mode = &config->base.adjusted_mode;
+
+	if (drm_mode_is_420_only(info, mode)) {
+		return intel_hdmi_ycbcr420_config(connector, config,
+					  clock_12bpc, clock_8bpc);
+	}
+
+	return false;
+}
+
 void lspcon_resume(struct intel_lspcon *lspcon)
 {
 	enum drm_lspcon_mode expected_mode;
@@ -233,6 +248,7 @@ bool lspcon_init(struct intel_digital_port *intel_dig_port)
 	struct intel_lspcon *lspcon = &intel_dig_port->lspcon;
 	struct drm_device *dev = intel_dig_port->base.base.dev;
 	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct drm_connector *connector = &dp->attached_connector->base;
 
 	if (!IS_GEN9(dev_priv)) {
 		DRM_ERROR("LSPCON is supported on GEN9 only\n");
@@ -264,6 +280,7 @@ bool lspcon_init(struct intel_digital_port *intel_dig_port)
 		return false;
 	}
 
+	connector->ycbcr_420_allowed = true;
 	drm_dp_read_desc(&dp->aux, &dp->desc, drm_dp_is_branch(dp->dpcd));
 
 	DRM_DEBUG_KMS("Success: LSPCON init\n");
-- 
2.7.4



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