Skip to content

Display

Introduction

MIPI-DSI and LVDS

DART-MX8M SoC supports MIPI-DSI interface. DART-MX8M can be optionally equipped with SN65DSI84 MIPI-DSI to LVDS bridge.
DART-MX8M carrier board comes with LVDS connectors, so you can easily connect LVDS display.
Connecting MIPI-DSI display to DART-MX8M carrier board requires designing a custom connector.

Adding custom LVDS panel

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

Referencing custom panel in the DTS file

The following code references Variscite panel in arch/arm64/boot/dts/freescale/ under kernel source tree

    &panel_lvds {
        compatible = "panel-lvds";
        data-mapping = "jeida-24";
        width-mm = <154>;
        height-mm = <87>;

        panel-timing {
            clock-frequency = <39000000>;
            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 should modify the "data-mapping", "width-mm", "height-mm" and "display-timings" properties to match your panel specification and rebuild the DTB file.

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://man.archlinux.org/man/weston.ini.5.en#transform=
* https://github.com/nxp-imx/weston-imx/blob/weston-imx-12.0.3/man/weston.ini.man#L521