drm/rockchip: dw-hdmi: Support hdmi quantization range setting

Adding hdmi quantization range switching function. The current
version use default quant range, subsequent version will keep consistent
with the kernel Setting.

Change-Id: Ibb93f7c08d72322caa15f12b1d6e1f901371b27b
Signed-off-by: Algea Cao <algea.cao@rock-chips.com>

common/edid.c

@@ -2748,6 +2748,24 @@ static void drm_parse_hdmi_forum_vsdb(struct hdmi_edid_data *data,
 	drm_parse_ycbcr420_deep_color_info(data, hf_vsdb);
 }
 
+/**
+ * drm_default_rgb_quant_range - default RGB quantization range
+ * @mode: display mode
+ *
+ * Determine the default RGB quantization range for the mode,
+ * as specified in CEA-861.
+ *
+ * Return: The default RGB quantization range for the mode
+ */
+enum hdmi_quantization_range
+drm_default_rgb_quant_range(struct drm_display_mode *mode)
+{
+	/* All CEA modes other than VIC 1 use limited quantization range. */
+	return drm_match_cea_mode(mode) > 1 ?
+		HDMI_QUANTIZATION_RANGE_LIMITED :
+		HDMI_QUANTIZATION_RANGE_FULL;
+}
+
 static void drm_parse_hdmi_deep_color_info(struct hdmi_edid_data *data,
 					   const u8 *hdmi)
 {
@@ -5157,6 +5175,50 @@ static int hdmi_vendor_infoframe_init(struct hdmi_vendor_infoframe *frame)
 	return 0;
 }
 
+/**
+ * drm_hdmi_avi_infoframe_quant_range() - fill the HDMI AVI infoframe
+ *                                        quantization range information
+ * @frame: HDMI AVI infoframe
+ * @rgb_quant_range: RGB quantization range (Q)
+ * @rgb_quant_range_selectable: Sink support selectable RGB quantization range (QS)
+ */
+void
+drm_hdmi_avi_infoframe_quant_range(struct hdmi_avi_infoframe *frame,
+				   struct drm_display_mode *mode,
+				   enum hdmi_quantization_range rgb_quant_range,
+				   bool rgb_quant_range_selectable)
+{
+	/*
+	 * CEA-861:
+	 * "A Source shall not send a non-zero Q value that does not correspond
+	 *  to the default RGB Quantization Range for the transmitted Picture
+	 *  unless the Sink indicates support for the Q bit in a Video
+	 *  Capabilities Data Block."
+	 *
+	 * HDMI 2.0 recommends sending non-zero Q when it does match the
+	 * default RGB quantization range for the mode, even when QS=0.
+	 */
+	if (rgb_quant_range_selectable ||
+	    rgb_quant_range == drm_default_rgb_quant_range(mode))
+		frame->quantization_range = rgb_quant_range;
+	else
+		frame->quantization_range = HDMI_QUANTIZATION_RANGE_DEFAULT;
+
+	/*
+	 * CEA-861-F:
+	 * "When transmitting any RGB colorimetry, the Source should set the
+	 *  YQ-field to match the RGB Quantization Range being transmitted
+	 *  (e.g., when Limited Range RGB, set YQ=0 or when Full Range RGB,
+	 *  set YQ=1) and the Sink shall ignore the YQ-field."
+	 */
+	if (rgb_quant_range == HDMI_QUANTIZATION_RANGE_LIMITED)
+		frame->ycc_quantization_range =
+			HDMI_YCC_QUANTIZATION_RANGE_LIMITED;
+	else
+		frame->ycc_quantization_range =
+			HDMI_YCC_QUANTIZATION_RANGE_FULL;
+}
+
 static enum hdmi_3d_structure
 s3d_structure_from_display_mode(const struct drm_display_mode *mode)
 {

drivers/video/drm/dw_hdmi.c

@@ -111,6 +111,12 @@ static const u16 csc_coeff_rgb_in_eitu709[3][4] = {
 	{ 0x6756, 0x78ab, 0x2000, 0x0200 }
 };
 
+static const u16 csc_coeff_full_to_limited[3][4] = {
+	{ 0x36f7, 0x0000, 0x0000, 0x0040 },
+	{ 0x0000, 0x36f7, 0x0000, 0x0040 },
+	{ 0x0000, 0x0000, 0x36f7, 0x0040 }
+};
+
 struct hdmi_vmode {
 	bool mdataenablepolarity;
 
@@ -125,6 +131,7 @@ struct hdmi_data_info {
 	unsigned int enc_out_bus_format;
 	unsigned int enc_in_encoding;
 	unsigned int enc_out_encoding;
+	unsigned int quant_range;
 	unsigned int pix_repet_factor;
 	struct hdmi_vmode video_mode;
 };
@@ -327,8 +334,26 @@ static int hdmi_bus_fmt_color_depth(unsigned int bus_format)
 
 static int is_color_space_conversion(struct dw_hdmi *hdmi)
 {
-	return hdmi->hdmi_data.enc_in_bus_format !=
+	struct drm_display_mode *mode =
-	hdmi->hdmi_data.enc_out_bus_format;
+		hdmi->edid_data.preferred_mode;
+	bool is_cea_default;
+
+	is_cea_default = (drm_match_cea_mode(mode) > 1) &&
+			 (hdmi->hdmi_data.quant_range ==
+			  HDMI_QUANTIZATION_RANGE_DEFAULT);
+
+	/*
+	 * When output is rgb limited range or default range with
+	 * cea mode, csc should be enabled.
+	 */
+	if (hdmi->hdmi_data.enc_in_bus_format !=
+	    hdmi->hdmi_data.enc_out_bus_format ||
+	    ((hdmi->hdmi_data.quant_range == HDMI_QUANTIZATION_RANGE_LIMITED ||
+	      is_cea_default) &&
+	     hdmi_bus_fmt_is_rgb(hdmi->hdmi_data.enc_in_bus_format)))
+		return 1;
+
+	return 0;
 }
 
 static int is_color_space_decimation(struct dw_hdmi *hdmi)
@@ -1139,16 +1164,22 @@ static void dw_hdmi_update_csc_coeffs(struct dw_hdmi *hdmi)
 	const u16 (*csc_coeff)[3][4] = &csc_coeff_default;
 	unsigned i;
 	u32 csc_scale = 1;
+	int enc_out_rgb, enc_in_rgb;
+
+	enc_out_rgb = hdmi_bus_fmt_is_rgb(hdmi->hdmi_data.enc_out_bus_format);
+	enc_in_rgb = hdmi_bus_fmt_is_rgb(hdmi->hdmi_data.enc_in_bus_format);
 
 	if (is_color_space_conversion(hdmi)) {
-		if (hdmi_bus_fmt_is_rgb(hdmi->hdmi_data.enc_out_bus_format)) {
+		if (enc_out_rgb == enc_in_rgb) {
+			csc_coeff = &csc_coeff_full_to_limited;
+			csc_scale = 0;
+		} else if (enc_out_rgb) {
 			if (hdmi->hdmi_data.enc_out_encoding ==
 						V4L2_YCBCR_ENC_601)
 				csc_coeff = &csc_coeff_rgb_out_eitu601;
 			else
 				csc_coeff = &csc_coeff_rgb_out_eitu709;
-		} else if (hdmi_bus_fmt_is_rgb(
+		} else if (enc_in_rgb) {
-					hdmi->hdmi_data.enc_in_bus_format)) {
 			if (hdmi->hdmi_data.enc_out_encoding ==
 						V4L2_YCBCR_ENC_601)
 				csc_coeff = &csc_coeff_rgb_in_eitu601;
@@ -1513,6 +1544,8 @@ static void hdmi_config_AVI(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
 	struct hdmi_avi_infoframe frame;
 	u8 val;
 	bool is_hdmi2 = false;
+	enum hdmi_quantization_range rgb_quant_range =
+		hdmi->hdmi_data.quant_range;
 
 	if (hdmi_bus_fmt_is_yuv420(hdmi->hdmi_data.enc_out_bus_format) ||
 	    hdmi->edid_data.display_info.hdmi.scdc.supported)
@@ -1520,6 +1553,12 @@ static void hdmi_config_AVI(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
 	/* Initialise info frame from DRM mode */
 	drm_hdmi_avi_infoframe_from_display_mode(&frame, mode, is_hdmi2);
 
+	/*
+	 * Ignore monitor selectable quantization, use quantization set
+	 * by the user
+	 */
+	drm_hdmi_avi_infoframe_quant_range(&frame, mode, rgb_quant_range,
+					   true);
 	if (hdmi_bus_fmt_is_yuv444(hdmi->hdmi_data.enc_out_bus_format))
 		frame.colorspace = HDMI_COLORSPACE_YUV444;
 	else if (hdmi_bus_fmt_is_yuv422(hdmi->hdmi_data.enc_out_bus_format))
@@ -2034,6 +2073,13 @@ static int dw_hdmi_setup(struct dw_hdmi *hdmi,
 			hdmi->plat_data->input_bus_encoding;
 	else
 		hdmi->hdmi_data.enc_in_encoding = V4L2_YCBCR_ENC_DEFAULT;
+
+	if (hdmi->plat_data->get_quant_range)
+		hdmi->hdmi_data.quant_range =
+			hdmi->plat_data->get_quant_range(data);
+	else
+		hdmi->hdmi_data.quant_range = HDMI_QUANTIZATION_RANGE_DEFAULT;
+
 	/*
 	 * According to the dw-hdmi specification 6.4.2
 	 * vp_pr_cd[3:0]:

include/edid.h

@@ -847,6 +847,8 @@ bool drm_detect_hdmi_monitor(struct edid *edid);
 bool drm_detect_monitor_audio(struct edid *edid);
 int do_cea_modes(struct hdmi_edid_data *data, const u8 *db, u8 len);
 int drm_do_get_edid(struct ddc_adapter *adap, u8 *edid);
+enum hdmi_quantization_range
+drm_default_rgb_quant_range(struct drm_display_mode *mode);
 u8 drm_scdc_readb(struct ddc_adapter *adap, u8 offset,
 		  u8 *value);
 u8 drm_scdc_writeb(struct ddc_adapter *adap, u8 offset,

include/linux/dw_hdmi.h

@@ -163,6 +163,7 @@ struct dw_hdmi_plat_data {
 	unsigned long (*get_output_bus_format)(void *data);
 	unsigned long (*get_enc_in_encoding)(void *data);
 	unsigned long (*get_enc_out_encoding)(void *data);
+	unsigned long (*get_quant_range)(void *data);
 };
 
 #endif /* __IMX_HDMI_H__ */

include/linux/hdmi.h

@@ -322,6 +322,11 @@ int
 drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame,
 					 struct drm_display_mode *mode,
 					 bool is_hdmi2_sink);
+void
+drm_hdmi_avi_infoframe_quant_range(struct hdmi_avi_infoframe *frame,
+				   struct drm_display_mode *mode,
+				   enum hdmi_quantization_range rgb_quant_range,
+				   bool rgb_quant_range_selectable);
 u8 drm_match_cea_mode(struct drm_display_mode *to_match);
 
 #endif /* _DRM_HDMI_H */