LVGL ported to AM62L (Texas Instruments)

Overview

This guide provides steps to setup the SK-AM62L and to cross-compile an LVGL application to run it on the target.

Buy

Coming soon.

Benchmark

The default buffering is fbdev.

Check out SK-AM62L in action, running LVGL's benchmark demo:

Frame buffer, 32 bit color depth, 1 thread

Name	Avg. CPU	Avg. FPS	Avg. time	render time	flush time
Empty screen	40%	26	14	4	10
Moving wallpaper	70%	29	25	15	10
Single rectangle	17%	29	0	0	0
Multiple rectangles	23%	29	7	2	5
Multiple RGB images	63%	30	19	9	10
Multiple ARGB images	81%	29	23	13	10
Rotated ARGB images	98%	24	39	29	10
Multiple labels	99%	29	28	18	10
Screen sized text	96%	20	47	37	10
Multiple arcs	93%	29	26	16	10
Containers	90%	23	33	27	6
Containers with overlay	99%	12	71	61	10
Containers with opa	99%	13	58	49	9
Containers with opa_layer	99%	9	87	77	10
Containers with scrolling	99%	14	58	49	9
Widgets demo	31%	25	15	13	2
All scenes avg.	74%	23	34	26	8

Frame buffer, 32 bit color depth, 2 threads

Name	Avg. CPU	Avg. FPS	Avg. time	render time	flush time
Empty screen	39%	26	14	4	10
Moving wallpaper	70%	30	24	14	10
Single rectangle	15%	29	0	0	0
Multiple rectangles	25%	29	8	3	5
Multiple RGB images	63%	29	19	9	10
Multiple ARGB images	80%	29	23	13	10
Rotated ARGB images	85%	29	28	18	10
Multiple labels	90%	29	24	14	10
Screen sized text	94%	28	32	22	10
Multiple arcs	89%	29	25	15	10
Containers	81%	26	24	21	3
Containers with overlay	99%	13	63	53	10
Containers with opa	99%	15	52	42	10
Containers with opa_layer	99%	9	90	80	10
Containers with scrolling	99%	16	53	43	10
Widgets demo	32%	25	15	13	2
All scenes avg.	72%	24	30	22	8

The other configurations are:

• DRM
• Wayland

Any of these buffering strategies can be used with multiple threads to render the frames.

Specification

CPU and memory

• MCU:

  • AM625 with Dual 64-bit Arm Cortex-A53 up to 1.25GHz

• RAM: 2GB DDR4

  • 16-bits data bus
  • Supports speeds up to 1600 MT/s

• Flash: Micro SD Card

• GPU: No GPU

Display

• Screen: HDMI 1920x1080 @ 60fps touchscreen

Connectivity

• 1 Type-A USB 2.0
• 1 Type-C dual-role device (DRD) USB 2.0 supports USB booting
• UART
• USB
• Onboard XDS110 Joint Test Action Group (JTAG) emulator
• 4 universal asynchronous receiver-transmitters (UARTs) via USB 2.0-B
• Ethernet
• Headphone jack

Getting started

Hardware setup

Coming soon.

Software setup

This guide was tested on Ubuntu 20.04 host.

Install docker

• Follow this tutorial (Ubuntu 22.04) (Ubuntu 20.04) to install and setup docker on your system.

• Support to run arm64 docker containers on the host:

  sudo apt-get install qemu-user-static
  docker run --rm --privileged multiarch/qemu-user-static --reset -p yes

Install utilities

sudo apt install picocom nmap

Run the default project

Clone the repository:

git clone --recurse-submodules https://github.com/lvgl/lv_port_texas_sk-am62l.git

IMPORTANT:

• default application from lv_port_linux runs the widget demo. To run the benchmark demo, modify lv_port_linux/main.c :

  /*Create a Demo*/
  // lv_demo_widgets();
  // lv_demo_widgets_start_slideshow();
  lv_demo_benchmark();

• The default lv_conf.h might not be the best configuration for the board. Feel free to replace the default lv_conf.h with one generated from one of the .defaults files in in lv_conf_example folder.

  cd lv_port_linux
  python3 lvgl/scripts/generate_lv_conf.py --defaults ../lv_conf_example/lv_conf_fb_2_threads.defaults

Build the docker image and the lvgl benchmark application:

cd lv_port_texas_sk-am62l
./native_build/scripts/docker_setup.sh --create-image
./native_build/scripts/docker_setup.sh --build-app

Note: Use the same commands ./arm_build/scripts/docker_setup.sh to build the app on an simulated Arm environment. It's required to use DRM or Wayland.

Run the executable on the target:

• Get the IP of the target board:

  • Option 1: from the UART, on the board:

    sudo picocom -b 115200 /dev/ttyUSB0
    ## Then inside the console, log as "root", no password required
    ## Then retrieve the ip of the board
    ip a

  • Option 2: Get the IP from your host with nmap

    ## Find the IP of the board. You need to know your ip (ifconfig or ip a)
    ## HOST_IP should be built like this :
    ## If the ip is 192.168.1.86, in the following command HOST_IP = 192.168.1.0/24
    nmap -sn <HOST_IP>/24 | grep am62xx

• Then transfer the executable on the board:

  scp lv_port_linux/bin/lvglsim root@<BOARD_IP>:/root

• Start the application

  ssh root@<BOARD_IP>
  
  export LV_LINUX_FBDEV_DEVICE=/dev/fb1
  
  ./lvglsim

Change configuration

Some configurations are provided in the folder lvgl_conf_example .

The default configuration used is lv_conf_fb_1_thread.defaults. To change the configuration, modify the lv_port_linux/lv_conf.h file with the desired configuration.

You can also edit any of the .defaults files and generate a new lv_conf.h based on it.

cd lv_port_linux
python3 lvgl/scripts/generate_lv_conf.py --defaults ../lv_conf_example/lv_conf_fb_1_thread.defaults

Start with your own application

The folder lv_port_linux is an example of an application using LVGL.

LVGL is integrated as a submodule in the folder. To change the version of the library:

cd lv_port_linux
git checkout <branch_name_or_commit_hash>

The file main.c is the default application provided and is configured to run the benchmark demo provided by LVGL library.

The main steps to create your own application are:

• Modify main.c
• Add any folders and files to extend the functionalities
• Update Dockerfile to add any package
• Modify CMakeLists.txt provided file to ensure all the required files are compiled and linked
• Use the docker scripts provided to build the application for ARM64 architecture.

TroubleShooting

Output folder permissions

If there is any problem with the output folder generated permissions, modify the permissions:

sudo chown -R $(whoami):$(whoami) lv_port_linux/bin

Fbdev example runtime error

This error can be printed when running the application:

[Warn]	(1382.767, +37)	 lv_display_refr_timer: No draw buffer lv_refr.c:374
[Warn]	(1382.804, +37)	 lv_display_refr_timer: No draw buffer lv_refr.c:374
[Warn]	(1382.841, +37)	 lv_display_refr_timer: No draw buffer lv_refr.c:374
[Warn]	(1382.878, +37)	 lv_display_refr_timer: No draw buffer lv_refr.c:374

To fix the issue find the existing fbdev available:

ls /dev/fb*

Export the variable to match the fbdev name:

export LV_LINUX_FBDEV_DEVICE=/dev/fb0

Wayland example runtime error

While running the application, if there is an error about XDG_RUNTIME_DIR, add the following environment variable on the board.

export XDG_RUNTIME_DIR=/run/user/1000

Changing configuration causes errors building the application

CMake may have troubles with CMakeLists.txt changes with some variables setup. If there is any problem building, try to clean the build folder:

rm -rf lv_port_linux/build-arm64* lv_port_linux/bin

Contribution and Support

If you find any issues with the development board feel free to open an Issue in this repository. For LVGL related issues (features, bugs, etc) please use the main lvgl repository.

If you found a bug and found a solution too please send a Pull request. If you are new to Pull requests refer to Our Guide to learn the basics.