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+Amlogic specific extensions to the Synopsys Designware HDMI Controller
+======================================================================
+
+The Amlogic Meson Synopsys Designware Integration is composed of :
+- A Synopsys DesignWare HDMI Controller IP
+- A TOP control block controlling the Clocks and PHY
+- A custom HDMI PHY in order to convert video to TMDS signal
+ ___________________________________
+| HDMI TOP |<= HPD
+|___________________________________|
+| | |
+| Synopsys HDMI | HDMI PHY |=> TMDS
+| Controller |________________|
+|___________________________________|<=> DDC
+
+The HDMI TOP block only supports HPD sensing.
+The Synopsys HDMI Controller interrupt is routed through the
+TOP Block interrupt.
+Communication to the TOP Block and the Synopsys HDMI Controller is done
+via a pair of dedicated addr+read/write registers.
+The HDMI PHY is configured by registers in the HHI register block.
+
+Pixel data arrives in 4:4:4 format from the VENC block and the VPU HDMI mux
+selects either the ENCI encoder for the 576i or 480i formats or the ENCP
+encoder for all the other formats including interlaced HD formats.
+
+The VENC uses a DVI encoder on top of the ENCI or ENCP encoders to generate
+DVI timings for the HDMI controller.
+
+Amlogic Meson GXBB, GXL and GXM SoCs families embeds the Synopsys DesignWare
+HDMI TX IP version 2.01a with HDCP and I2C & S/PDIF
+audio source interfaces.
+
+Required properties:
+- compatible: value should be different for each SoC family as :
+ - GXBB (S905) : "amlogic,meson-gxbb-dw-hdmi"
+ - GXL (S905X, S905D) : "amlogic,meson-gxl-dw-hdmi"
+ - GXM (S912) : "amlogic,meson-gxm-dw-hdmi"
+ followed by the common "amlogic,meson-gx-dw-hdmi"
+- reg: Physical base address and length of the controller's registers.
+- interrupts: The HDMI interrupt number
+- clocks, clock-names : must have the phandles to the HDMI iahb and isfr clocks,
+ and the Amlogic Meson venci clocks as described in
+ Documentation/devicetree/bindings/clock/clock-bindings.txt,
+ the clocks are soc specific, the clock-names should be "iahb", "isfr", "venci"
+- resets, resets-names: must have the phandles to the HDMI apb, glue and phy
+ resets as described in :
+ Documentation/devicetree/bindings/reset/reset.txt,
+ the reset-names should be "hdmitx_apb", "hdmitx", "hdmitx_phy"
+
+Required nodes:
+
+The connections to the HDMI ports are modeled using the OF graph
+bindings specified in Documentation/devicetree/bindings/graph.txt.
+
+The following table lists for each supported model the port number
+corresponding to each HDMI output and input.
+
+ Port 0 Port 1
+-----------------------------------------
+ S905 (GXBB) VENC Input TMDS Output
+ S905X (GXL) VENC Input TMDS Output
+ S905D (GXL) VENC Input TMDS Output
+ S912 (GXM) VENC Input TMDS Output
+
+Example:
+
+hdmi-connector {
+ compatible = "hdmi-connector";
+ type = "a";
+
+ port {
+ hdmi_connector_in: endpoint {
+ remote-endpoint = <&hdmi_tx_tmds_out>;
+ };
+ };
+};
+
+hdmi_tx: hdmi-tx@c883a000 {
+ compatible = "amlogic,meson-gxbb-dw-hdmi", "amlogic,meson-gx-dw-hdmi";
+ reg = <0x0 0xc883a000 0x0 0x1c>;
+ interrupts = <GIC_SPI 57 IRQ_TYPE_EDGE_RISING>;
+ resets = <&reset RESET_HDMITX_CAPB3>,
+ <&reset RESET_HDMI_SYSTEM_RESET>,
+ <&reset RESET_HDMI_TX>;
+ reset-names = "hdmitx_apb", "hdmitx", "hdmitx_phy";
+ clocks = <&clkc CLKID_HDMI_PCLK>,
+ <&clkc CLKID_CLK81>,
+ <&clkc CLKID_GCLK_VENCI_INT0>;
+ clock-names = "isfr", "iahb", "venci";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ /* VPU VENC Input */
+ hdmi_tx_venc_port: port@0 {
+ reg = <0>;
+
+ hdmi_tx_in: endpoint {
+ remote-endpoint = <&hdmi_tx_out>;
+ };
+ };
+
+ /* TMDS Output */
+ hdmi_tx_tmds_port: port@1 {
+ reg = <1>;
+
+ hdmi_tx_tmds_out: endpoint {
+ remote-endpoint = <&hdmi_connector_in>;
+ };
+ };
+};