DART-MX8M-PLUS Display

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DART-MX8M-PLUS Display

1 HDMI, MIPI-DSI and LVDS

DART-MX8M-PLUS SoC supports LVDS, HDMI and MIPI-DSI interfaces. DART-MX8M-PLUS carrier board comes with LVDS and HDMI connectors, so you can easily connect LVDS and HDMI displays.
Connecting MIPI-DSI display to DART-MX8M-PLUS carrier board requires designing a custom connector.

2 Adding custom LVDS panel

DART-MX8M-PLUS evaluation kit comes with 800x480 LCD panel. DART-MX8M-PLUS DTS file was created with this panel in mind.
To support a custom LVDS panel you should make several modifications.

The following code references Variscite panel in arch/arm64/boot/dts/freescale/imx8mp-var-dart.dtb under kernel source tree

panel {
	compatible = "sgd,gktw70sdae4se", "panel-lvds";
	backlight = <&backlight>;
	width-mm = <153>;
	height-mm = <87>;
	label = "gktw70sdae4se";
	data-mapping = "jeida-24";
	status = "okay";

	panel-timing {
		clock-frequency = <33000000>;
		hactive = <800>;
		vactive = <480>;
		hback-porch = <40>;
		hfront-porch = <40>;
		vback-porch = <29>;
		vfront-porch = <13>;
		hsync-len = <48>;
		vsync-len = <3>;
		hsync-active = <0>;
		vsync-active = <0>;
		de-active = <1>;
	};
...
};

&ldb {
        status = "okay";

        lvds-channel@0 {
                fsl,data-mapping = "jeida";
                fsl,data-width = <24>;
                status = "okay";
...
};

You should modify panel "data-mapping" and "display-timings" properties to match your panel specification.
You should also modify ldb (internal LVDS bridge) "fsl,data-mapping" and "fsl,data-width" properties to match your panel specification.
Supported "data-mapping" values are "jeida-18", "jeida-24" and "vesa-24".
Supported "fsl,data-mapping" values are "jeida", and "spwg".
Supported "fsl,data-width" values are <18>, and <24>.

For dual channel LVDS panels add fsl,dual-channel property to ldb node, as in the example below:

&ldb {
        status = "okay";
        fsl,dual-channel;

        lvds-channel@0 {
                fsl,data-mapping = "jeida";
                fsl,data-width = <24>;
                status = "okay";
...
};