dt-bindings: drm/mediatek: Add Mediatek display subsystem dts binding

Add device tree binding documentation for the display subsystem in
Mediatek MT8173 SoCs.

Signed-off-by: CK Hu <[e-mail]>
Signed-off-by: Philipp Zabel <[e-mail]>
Acked-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/display/mediatek/mediatek,disp.txt

···
+Mediatek display subsystem
+==========================
+
+The Mediatek display subsystem consists of various DISP function blocks in the
+MMSYS register space. The connections between them can be configured by output
+and input selectors in the MMSYS_CONFIG register space. Pixel clock and start
+of frame signal are distributed to the other function blocks by a DISP_MUTEX
+function block.
+
+All DISP device tree nodes must be siblings to the central MMSYS_CONFIG node.
+For a description of the MMSYS_CONFIG binding, see
+Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.txt.
+
+DISP function blocks
+====================
+
+A display stream starts at a source function block that reads pixel data from
+memory and ends with a sink function block that drives pixels on a display
+interface, or writes pixels back to memory. All DISP function blocks have
+their own register space, interrupt, and clock gate. The blocks that can
+access memory additionally have to list the IOMMU and local arbiter they are
+connected to.
+
+For a description of the display interface sink function blocks, see
+Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt and
+Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.txt.
+
+Required properties (all function blocks):
+- compatible: "mediatek,<chip>-disp-<function>", one of
+	"mediatek,<chip>-disp-ovl"   - overlay (4 layers, blending, csc)
+	"mediatek,<chip>-disp-rdma"  - read DMA / line buffer
+	"mediatek,<chip>-disp-wdma"  - write DMA
+	"mediatek,<chip>-disp-color" - color processor
+	"mediatek,<chip>-disp-aal"   - adaptive ambient light controller
+	"mediatek,<chip>-disp-gamma" - gamma correction
+	"mediatek,<chip>-disp-merge" - merge streams from two RDMA sources
+	"mediatek,<chip>-disp-split" - split stream to two encoders
+	"mediatek,<chip>-disp-ufoe"  - data compression engine
+	"mediatek,<chip>-dsi"        - DSI controller, see mediatek,dsi.txt
+	"mediatek,<chip>-dpi"        - DPI controller, see mediatek,dpi.txt
+	"mediatek,<chip>-disp-mutex" - display mutex
+	"mediatek,<chip>-disp-od"    - overdrive
+- reg: Physical base address and length of the function block register space
+- interrupts: The interrupt signal from the function block (required, except for
+  merge and split function blocks).
+- clocks: device clocks
+  See Documentation/devicetree/bindings/clock/clock-bindings.txt for details.
+  For most function blocks this is just a single clock input. Only the DSI and
+  DPI controller nodes have multiple clock inputs. These are documented in
+  mediatek,dsi.txt and mediatek,dpi.txt, respectively.
+
+Required properties (DMA function blocks):
+- compatible: Should be one of
+	"mediatek,<chip>-disp-ovl"
+	"mediatek,<chip>-disp-rdma"
+	"mediatek,<chip>-disp-wdma"
+- larb: Should contain a phandle pointing to the local arbiter device as defined
+  in Documentation/devicetree/bindings/soc/mediatek/mediatek,smi-larb.txt
+- iommus: Should point to the respective IOMMU block with master port as
+  argument, see Documentation/devicetree/bindings/iommu/mediatek,iommu.txt
+  for details.
+
+Examples:
+
+mmsys: clock-controller@14000000 {
+	compatible = "mediatek,mt8173-mmsys", "syscon";
+	reg = <0 0x14000000 0 0x1000>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	#clock-cells = <1>;
+};
+
+ovl0: ovl@1400c000 {
+	compatible = "mediatek,mt8173-disp-ovl";
+	reg = <0 0x1400c000 0 0x1000>;
+	interrupts = <GIC_SPI 180 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_OVL0>;
+	iommus = <&iommu M4U_PORT_DISP_OVL0>;
+	mediatek,larb = <&larb0>;
+};
+
+ovl1: ovl@1400d000 {
+	compatible = "mediatek,mt8173-disp-ovl";
+	reg = <0 0x1400d000 0 0x1000>;
+	interrupts = <GIC_SPI 181 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_OVL1>;
+	iommus = <&iommu M4U_PORT_DISP_OVL1>;
+	mediatek,larb = <&larb4>;
+};
+
+rdma0: rdma@1400e000 {
+	compatible = "mediatek,mt8173-disp-rdma";
+	reg = <0 0x1400e000 0 0x1000>;
+	interrupts = <GIC_SPI 182 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_RDMA0>;
+	iommus = <&iommu M4U_PORT_DISP_RDMA0>;
+	mediatek,larb = <&larb0>;
+};
+
+rdma1: rdma@1400f000 {
+	compatible = "mediatek,mt8173-disp-rdma";
+	reg = <0 0x1400f000 0 0x1000>;
+	interrupts = <GIC_SPI 183 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_RDMA1>;
+	iommus = <&iommu M4U_PORT_DISP_RDMA1>;
+	mediatek,larb = <&larb4>;
+};
+
+rdma2: rdma@14010000 {
+	compatible = "mediatek,mt8173-disp-rdma";
+	reg = <0 0x14010000 0 0x1000>;
+	interrupts = <GIC_SPI 184 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_RDMA2>;
+	iommus = <&iommu M4U_PORT_DISP_RDMA2>;
+	mediatek,larb = <&larb4>;
+};
+
+wdma0: wdma@14011000 {
+	compatible = "mediatek,mt8173-disp-wdma";
+	reg = <0 0x14011000 0 0x1000>;
+	interrupts = <GIC_SPI 185 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_WDMA0>;
+	iommus = <&iommu M4U_PORT_DISP_WDMA0>;
+	mediatek,larb = <&larb0>;
+};
+
+wdma1: wdma@14012000 {
+	compatible = "mediatek,mt8173-disp-wdma";
+	reg = <0 0x14012000 0 0x1000>;
+	interrupts = <GIC_SPI 186 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_WDMA1>;
+	iommus = <&iommu M4U_PORT_DISP_WDMA1>;
+	mediatek,larb = <&larb4>;
+};
+
+color0: color@14013000 {
+	compatible = "mediatek,mt8173-disp-color";
+	reg = <0 0x14013000 0 0x1000>;
+	interrupts = <GIC_SPI 187 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_COLOR0>;
+};
+
+color1: color@14014000 {
+	compatible = "mediatek,mt8173-disp-color";
+	reg = <0 0x14014000 0 0x1000>;
+	interrupts = <GIC_SPI 188 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_COLOR1>;
+};
+
+aal@14015000 {
+	compatible = "mediatek,mt8173-disp-aal";
+	reg = <0 0x14015000 0 0x1000>;
+	interrupts = <GIC_SPI 189 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_AAL>;
+};
+
+gamma@14016000 {
+	compatible = "mediatek,mt8173-disp-gamma";
+	reg = <0 0x14016000 0 0x1000>;
+	interrupts = <GIC_SPI 190 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_GAMMA>;
+};
+
+ufoe@1401a000 {
+	compatible = "mediatek,mt8173-disp-ufoe";
+	reg = <0 0x1401a000 0 0x1000>;
+	interrupts = <GIC_SPI 191 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_UFOE>;
+};
+
+dsi0: dsi@1401b000 {
+	/* See mediatek,dsi.txt for details */
+};
+
+dpi0: dpi@1401d000 {
+	/* See mediatek,dpi.txt for details */
+};
+
+mutex: mutex@14020000 {
+	compatible = "mediatek,mt8173-disp-mutex";
+	reg = <0 0x14020000 0 0x1000>;
+	interrupts = <GIC_SPI 169 IRQ_TYPE_LEVEL_LOW>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_MUTEX_32K>;
+};
+
+od@14023000 {
+	compatible = "mediatek,mt8173-disp-od";
+	reg = <0 0x14023000 0 0x1000>;
+	power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
+	clocks = <&mmsys CLK_MM_DISP_OD>;
+};

Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.txt

···
+Mediatek DPI Device
+===================
+
+The Mediatek DPI function block is a sink of the display subsystem and
+provides 8-bit RGB/YUV444 or 8/10/10-bit YUV422 pixel data on a parallel
+output bus.
+
+Required properties:
+- compatible: "mediatek,<chip>-dpi"
+- reg: Physical base address and length of the controller's registers
+- interrupts: The interrupt signal from the function block.
+- clocks: device clocks
+  See Documentation/devicetree/bindings/clock/clock-bindings.txt for details.
+- clock-names: must contain "pixel", "engine", and "pll"
+- port: Output port node with endpoint definitions as described in
+  Documentation/devicetree/bindings/graph.txt. This port should be connected
+  to the input port of an attached HDMI or LVDS encoder chip.
+
+Example:
+
+dpi0: dpi@1401d000 {
+	compatible = "mediatek,mt8173-dpi";
+	reg = <0 0x1401d000 0 0x1000>;
+	interrupts = <GIC_SPI 194 IRQ_TYPE_LEVEL_LOW>;
+	clocks = <&mmsys CLK_MM_DPI_PIXEL>,
+		 <&mmsys CLK_MM_DPI_ENGINE>,
+		 <&apmixedsys CLK_APMIXED_TVDPLL>;
+	clock-names = "pixel", "engine", "pll";
+
+	port {
+		dpi0_out: endpoint {
+			remote-endpoint = <&hdmi0_in>;
+		};
+	};
+};

Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.txt

···
+Mediatek DSI Device
+===================
+
+The Mediatek DSI function block is a sink of the display subsystem and can
+drive up to 4-lane MIPI DSI output. Two DSIs can be synchronized for dual-
+channel output.
+
+Required properties:
+- compatible: "mediatek,<chip>-dsi"
+- reg: Physical base address and length of the controller's registers
+- interrupts: The interrupt signal from the function block.
+- clocks: device clocks
+  See Documentation/devicetree/bindings/clock/clock-bindings.txt for details.
+- clock-names: must contain "engine", "digital", and "hs"
+- phys: phandle link to the MIPI D-PHY controller.
+- phy-names: must contain "dphy"
+- port: Output port node with endpoint definitions as described in
+  Documentation/devicetree/bindings/graph.txt. This port should be connected
+  to the input port of an attached DSI panel or DSI-to-eDP encoder chip.
+
+MIPI TX Configuration Module
+============================
+
+The MIPI TX configuration module controls the MIPI D-PHY.
+
+Required properties:
+- compatible: "mediatek,<chip>-mipi-tx"
+- reg: Physical base address and length of the controller's registers
+- clocks: PLL reference clock
+- clock-output-names: name of the output clock line to the DSI encoder
+- #clock-cells: must be <0>;
+- #phy-cells: must be <0>.
+
+Example:
+
+mipi_tx0: mipi-dphy@10215000 {
+	compatible = "mediatek,mt8173-mipi-tx";
+	reg = <0 0x10215000 0 0x1000>;
+	clocks = <&clk26m>;
+	clock-output-names = "mipi_tx0_pll";
+	#clock-cells = <0>;
+	#phy-cells = <0>;
+};
+
+dsi0: dsi@1401b000 {
+	compatible = "mediatek,mt8173-dsi";
+	reg = <0 0x1401b000 0 0x1000>;
+	interrupts = <GIC_SPI 192 IRQ_TYPE_LEVEL_LOW>;
+	clocks = <&mmsys MM_DSI0_ENGINE>, <&mmsys MM_DSI0_DIGITAL>,
+		 <&mipi_tx0>;
+	clock-names = "engine", "digital", "hs";
+	phys = <&mipi_tx0>;
+	phy-names = "dphy";
+
+	port {
+		dsi0_out: endpoint {
+			remote-endpoint = <&panel_in>;
+		};
+	};
+};