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Display

LVDS

VAR-SOM-MX8X supports one dual-channel LVDS interface.
VAR-SOM-MX8X evaluation kit comes with two LVDS connectors, one connector per LVDS channel.
By default Variscite panel is attached to LVDS#A connector.

Adding custom LVDS panel

VAR-SOM-MX8X evaluation kit comes with 800x480 LVDS panel.
VAR-SOM-MX8X DTS file was created with this panel in mind.
To support different LVDS panel, several modifications may be required.

The following code configures LVDS panel in arch/arm64/boot/dts/freescale/fsl-imx8qxp-var-som-common.dtsi under kernel source tree:

&ldb1_phy {
    status = "ok";
};

&ldb1 {
    status = "ok";
    lvds-channel@0 {
        fsl,data-mapping = "jeida";
        fsl,data-width = <24>;
        status = "ok";

        display-timings {
            lvds {
                clock-frequency = <29232000>;
                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>;
                pixelclk-active = <0>;
            };
        };
    };
};

You may need to modify "fsl,data-mapping", "fsl,data-width" and "display-timings" properties to match your panel specification.
For more information see Documentation/devicetree/bindings/display/imx/ldb.txt in the kernel source tree.

Setting Weston Desktop Resolution

The default Weston uses maximum resolution supported by display.
To modify Weston resolution, edit /etc/xdg/weston/weston.ini and set size parameter in shell section.
For example:

[shell]
size=3840x2160

For new settings to take effect restart weston by running

# systemctl restart weston

Rotating the Weston display

To rotate the Weston display, edit /etc/xdg/weston/weston.ini.

For example, rotate the display 90 degrees:

[output]

name=DSI-1
transform=rotate-90
For more information, see the Weston man pages: 
* https://github.com/nxp-imx/weston-imx/blob/weston-imx-12.0.3/man/weston.ini.man#L506