drm/radeon: Setup HDMI_CONTROL for hdmi deep color gcp's (v2)

Program HDMI_CONTROL to send general control packets
for hdmi deep color mode signalling at every video
frame if bpc > 8.

This is only supported on evergreen / DCE-4 and later.

v2: rebase
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/evergreen_hdmi.c

@@ -298,6 +298,7 @@ void evergreen_hdmi_setmode(struct drm_encoder *encoder, struct drm_display_mode
 	struct hdmi_avi_infoframe frame;
 	uint32_t offset;
 	ssize_t err;
+	uint32_t val;
 	int bpc = 8;
 
 	if (!dig || !dig->afmt)
@@ -330,6 +331,35 @@ void evergreen_hdmi_setmode(struct drm_encoder *encoder, struct drm_display_mode
 
 	WREG32(AFMT_AUDIO_CRC_CONTROL + offset, 0x1000);
 
+	val = RREG32(HDMI_CONTROL + offset);
+	val &= ~HDMI_DEEP_COLOR_ENABLE;
+	val &= ~HDMI_DEEP_COLOR_DEPTH_MASK;
+
+	switch (bpc) {
+		case 0:
+		case 6:
+		case 8:
+		case 16:
+		default:
+			DRM_DEBUG("%s: Disabling hdmi deep color for %d bpc.\n",
+					 drm_get_connector_name(connector), bpc);
+			break;
+		case 10:
+			val |= HDMI_DEEP_COLOR_ENABLE;
+			val |= HDMI_DEEP_COLOR_DEPTH(HDMI_30BIT_DEEP_COLOR);
+			DRM_DEBUG("%s: Enabling hdmi deep color 30 for 10 bpc.\n",
+					 drm_get_connector_name(connector));
+			break;
+		case 12:
+			val |= HDMI_DEEP_COLOR_ENABLE;
+			val |= HDMI_DEEP_COLOR_DEPTH(HDMI_36BIT_DEEP_COLOR);
+			DRM_DEBUG("%s: Enabling hdmi deep color 36 for 12 bpc.\n",
+					 drm_get_connector_name(connector));
+			break;
+	}
+
+	WREG32(HDMI_CONTROL + offset, val);
+
 	WREG32(HDMI_VBI_PACKET_CONTROL + offset,
 	       HDMI_NULL_SEND | /* send null packets when required */
 	       HDMI_GC_SEND | /* send general control packets */

drivers/gpu/drm/radeon/evergreend.h

@@ -517,10 +517,11 @@
 #       define HDMI_ERROR_ACK                (1 << 8)
 #       define HDMI_ERROR_MASK               (1 << 9)
 #       define HDMI_DEEP_COLOR_ENABLE        (1 << 24)
-#       define HDMI_DEEP_COLOR_DEPTH         (((x) & 3) << 28)
+#       define HDMI_DEEP_COLOR_DEPTH(x)      (((x) & 3) << 28)
 #       define HDMI_24BIT_DEEP_COLOR         0
 #       define HDMI_30BIT_DEEP_COLOR         1
 #       define HDMI_36BIT_DEEP_COLOR         2
+#       define HDMI_DEEP_COLOR_DEPTH_MASK    (3 << 28)
 #define HDMI_STATUS                          0x7034
 #       define HDMI_ACTIVE_AVMUTE            (1 << 0)
 #       define HDMI_AUDIO_PACKET_ERROR       (1 << 16)