DART-MX8M-MINI Display

From Variscite Wiki
Revision as of 23:11, 17 January 2023 by Nate (talk | contribs)
Warning: This page is designed to be used with a 'release' URL parameter.

This page is using the default release RELEASE_SUMO_V1.0_DART-MX8M-MINI.
To view this page for a specific Variscite SoM and software release, please follow these steps:

  1. Visit variwiki.com
  2. Select your SoM
  3. Select the software release
Display

Introduction

MIPI-DSI and LVDS

SoC supports MIPI-DSI interface.  can be optionally equipped with SN65DSI84 MIPI-DSI to LVDS bridge.
carrier board comes with LVDS connectors, so you can easily connect LVDS display.

Connecting MIPI-DSI display to carrier board requires designing a custom connector.

Adding custom LVDS panel

evaluation kit comes with 800x480 LCD panel.  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

	dsi_lvds_bridge: sn65dsi84@2c {
		compatible = "ti,sn65dsi83";
		reg = <0x2c>;
		ti,dsi-lanes = <1>;
		ti,lvds-format = <1>;
		ti,lvds-bpp = <24>;
		ti,width-mm = <154>;
		ti,height-mm = <87>;
		enable-gpios = <&gpio2 11 GPIO_ACTIVE_HIGH>;
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_lvds>;
		status = "okay";

		display-timings {
			lvds {
				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>;
				pixelclk-active = <0>;
			};
		};
        ...
        };

You should modify the "ti,dsi-lanes", "ti,lvds-format", "ti,lvds-bpp", "ti,width-mm", "ti,height-mm" and "display-timings" properties to match your panel specification and rebuild the DTB file.
To support a dual channel LVDS panel, please add "ti,lvds-channels = <2>".

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=90