drm/bridge: dw-hdmi: Add Dynamic Range and Mastering InfoFrame support

Add support for configuring Dynamic Range and Mastering InfoFrame from
the hdr_output_metadata connector property.

This patch adds a use_drm_infoframe flag to dw_hdmi_plat_data that platform
drivers use to signal when Dynamic Range and Mastering infoframes is supported.
This flag is needed because Amlogic GXBB and GXL report same DW-HDMI version,
and only GXL support DRM InfoFrame.

These changes were based on work done by Zheng Yang <zhengyang@rock-chips.com>
to support DRM InfoFrame on the Rockchip 4.4 BSP kernel at [1] and [2]

[1] https://github.com/rockchip-linux/kernel/tree/develop-4.4
[2] https://github.com/rockchip-linux/kernel/commit/d1943fde81ff41d7cca87f4a42f03992e90bddd5

Cc: Zheng Yang <zhengyang@rock-chips.com>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/HE1PR06MB4011D7B916CBF8B740ACC45FAC9B0@HE1PR06MB4011.eurprd06.prod.outlook.com

drivers/gpu/drm/bridge/synopsys/dw-hdmi.c

@@ -25,6 +25,7 @@
 #include <uapi/linux/videodev2.h>
 
 #include <drm/bridge/dw_hdmi.h>
+#include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
 #include <drm/drm_edid.h>
@@ -1743,6 +1744,41 @@ static void hdmi_config_vendor_specific_infoframe(struct dw_hdmi *hdmi,
 			HDMI_FC_DATAUTO0_VSD_MASK);
 }
 
+static void hdmi_config_drm_infoframe(struct dw_hdmi *hdmi)
+{
+	const struct drm_connector_state *conn_state = hdmi->connector.state;
+	struct hdmi_drm_infoframe frame;
+	u8 buffer[30];
+	ssize_t err;
+	int i;
+
+	if (!hdmi->plat_data->use_drm_infoframe)
+		return;
+
+	hdmi_modb(hdmi, HDMI_FC_PACKET_TX_EN_DRM_DISABLE,
+		  HDMI_FC_PACKET_TX_EN_DRM_MASK, HDMI_FC_PACKET_TX_EN);
+
+	err = drm_hdmi_infoframe_set_hdr_metadata(&frame, conn_state);
+	if (err < 0)
+		return;
+
+	err = hdmi_drm_infoframe_pack(&frame, buffer, sizeof(buffer));
+	if (err < 0) {
+		dev_err(hdmi->dev, "Failed to pack drm infoframe: %zd\n", err);
+		return;
+	}
+
+	hdmi_writeb(hdmi, frame.version, HDMI_FC_DRM_HB0);
+	hdmi_writeb(hdmi, frame.length, HDMI_FC_DRM_HB1);
+
+	for (i = 0; i < frame.length; i++)
+		hdmi_writeb(hdmi, buffer[4 + i], HDMI_FC_DRM_PB0 + i);
+
+	hdmi_writeb(hdmi, 1, HDMI_FC_DRM_UP);
+	hdmi_modb(hdmi, HDMI_FC_PACKET_TX_EN_DRM_ENABLE,
+		  HDMI_FC_PACKET_TX_EN_DRM_MASK, HDMI_FC_PACKET_TX_EN);
+}
+
 static void hdmi_av_composer(struct dw_hdmi *hdmi,
 			     const struct drm_display_mode *mode)
 {
@@ -2064,6 +2100,7 @@ static int dw_hdmi_setup(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
 		/* HDMI Initialization Step F - Configure AVI InfoFrame */
 		hdmi_config_AVI(hdmi, mode);
 		hdmi_config_vendor_specific_infoframe(hdmi, mode);
+		hdmi_config_drm_infoframe(hdmi);
 	} else {
 		dev_dbg(hdmi->dev, "%s DVI mode\n", __func__);
 	}
@@ -2230,6 +2267,45 @@ static int dw_hdmi_connector_get_modes(struct drm_connector *connector)
 	return ret;
 }
 
+static bool hdr_metadata_equal(const struct drm_connector_state *old_state,
+			       const struct drm_connector_state *new_state)
+{
+	struct drm_property_blob *old_blob = old_state->hdr_output_metadata;
+	struct drm_property_blob *new_blob = new_state->hdr_output_metadata;
+
+	if (!old_blob || !new_blob)
+		return old_blob == new_blob;
+
+	if (old_blob->length != new_blob->length)
+		return false;
+
+	return !memcmp(old_blob->data, new_blob->data, old_blob->length);
+}
+
+static int dw_hdmi_connector_atomic_check(struct drm_connector *connector,
+					  struct drm_atomic_state *state)
+{
+	struct drm_connector_state *old_state =
+		drm_atomic_get_old_connector_state(state, connector);
+	struct drm_connector_state *new_state =
+		drm_atomic_get_new_connector_state(state, connector);
+	struct drm_crtc *crtc = new_state->crtc;
+	struct drm_crtc_state *crtc_state;
+
+	if (!crtc)
+		return 0;
+
+	if (!hdr_metadata_equal(old_state, new_state)) {
+		crtc_state = drm_atomic_get_crtc_state(state, crtc);
+		if (IS_ERR(crtc_state))
+			return PTR_ERR(crtc_state);
+
+		crtc_state->mode_changed = true;
+	}
+
+	return 0;
+}
+
 static void dw_hdmi_connector_force(struct drm_connector *connector)
 {
 	struct dw_hdmi *hdmi = container_of(connector, struct dw_hdmi,
@@ -2254,6 +2330,7 @@ static const struct drm_connector_funcs dw_hdmi_connector_funcs = {
 
 static const struct drm_connector_helper_funcs dw_hdmi_connector_helper_funcs = {
 	.get_modes = dw_hdmi_connector_get_modes,
+	.atomic_check = dw_hdmi_connector_atomic_check,
 };
 
 static int dw_hdmi_bridge_attach(struct drm_bridge *bridge)
@@ -2274,6 +2351,10 @@ static int dw_hdmi_bridge_attach(struct drm_bridge *bridge)
 				    DRM_MODE_CONNECTOR_HDMIA,
 				    hdmi->ddc);
 
+	if (hdmi->version >= 0x200a && hdmi->plat_data->use_drm_infoframe)
+		drm_object_attach_property(&connector->base,
+			connector->dev->mode_config.hdr_output_metadata_property, 0);
+
 	drm_connector_attach_encoder(connector, encoder);
 
 	cec_fill_conn_info_from_drm(&conn_info, connector);

drivers/gpu/drm/bridge/synopsys/dw-hdmi.h

@@ -254,6 +254,7 @@
 #define HDMI_FC_POL2                            0x10DB
 #define HDMI_FC_PRCONF                          0x10E0
 #define HDMI_FC_SCRAMBLER_CTRL                  0x10E1
+#define HDMI_FC_PACKET_TX_EN                    0x10E3
 
 #define HDMI_FC_GMD_STAT                        0x1100
 #define HDMI_FC_GMD_EN                          0x1101
@@ -289,6 +290,37 @@
 #define HDMI_FC_GMD_PB26                        0x111F
 #define HDMI_FC_GMD_PB27                        0x1120
 
+#define HDMI_FC_DRM_UP                          0x1167
+#define HDMI_FC_DRM_HB0                         0x1168
+#define HDMI_FC_DRM_HB1                         0x1169
+#define HDMI_FC_DRM_PB0                         0x116A
+#define HDMI_FC_DRM_PB1                         0x116B
+#define HDMI_FC_DRM_PB2                         0x116C
+#define HDMI_FC_DRM_PB3                         0x116D
+#define HDMI_FC_DRM_PB4                         0x116E
+#define HDMI_FC_DRM_PB5                         0x116F
+#define HDMI_FC_DRM_PB6                         0x1170
+#define HDMI_FC_DRM_PB7                         0x1171
+#define HDMI_FC_DRM_PB8                         0x1172
+#define HDMI_FC_DRM_PB9                         0x1173
+#define HDMI_FC_DRM_PB10                        0x1174
+#define HDMI_FC_DRM_PB11                        0x1175
+#define HDMI_FC_DRM_PB12                        0x1176
+#define HDMI_FC_DRM_PB13                        0x1177
+#define HDMI_FC_DRM_PB14                        0x1178
+#define HDMI_FC_DRM_PB15                        0x1179
+#define HDMI_FC_DRM_PB16                        0x117A
+#define HDMI_FC_DRM_PB17                        0x117B
+#define HDMI_FC_DRM_PB18                        0x117C
+#define HDMI_FC_DRM_PB19                        0x117D
+#define HDMI_FC_DRM_PB20                        0x117E
+#define HDMI_FC_DRM_PB21                        0x117F
+#define HDMI_FC_DRM_PB22                        0x1180
+#define HDMI_FC_DRM_PB23                        0x1181
+#define HDMI_FC_DRM_PB24                        0x1182
+#define HDMI_FC_DRM_PB25                        0x1183
+#define HDMI_FC_DRM_PB26                        0x1184
+
 #define HDMI_FC_DBGFORCE                        0x1200
 #define HDMI_FC_DBGAUD0CH0                      0x1201
 #define HDMI_FC_DBGAUD1CH0                      0x1202
@@ -744,6 +776,11 @@ enum {
 	HDMI_FC_PRCONF_OUTPUT_PR_FACTOR_MASK = 0x0F,
 	HDMI_FC_PRCONF_OUTPUT_PR_FACTOR_OFFSET = 0,
 
+/* FC_PACKET_TX_EN field values */
+	HDMI_FC_PACKET_TX_EN_DRM_MASK = 0x80,
+	HDMI_FC_PACKET_TX_EN_DRM_ENABLE = 0x80,
+	HDMI_FC_PACKET_TX_EN_DRM_DISABLE = 0x00,
+
 /* FC_AVICONF0-FC_AVICONF3 field values */
 	HDMI_FC_AVICONF0_PIX_FMT_MASK = 0x03,
 	HDMI_FC_AVICONF0_PIX_FMT_RGB = 0x00,

include/drm/bridge/dw_hdmi.h

@@ -126,6 +126,7 @@ struct dw_hdmi_plat_data {
 					   const struct drm_display_mode *mode);
 	unsigned long input_bus_format;
 	unsigned long input_bus_encoding;
+	bool use_drm_infoframe;
 
 	/* Vendor PHY support */
 	const struct dw_hdmi_phy_ops *phy_ops;