Hibernation mode (suspend to disk) will be useful for boot time optimization, especially under heavy application usage cases. This article is a quick guide for how to enable hibernation mode in Linux running on i.MX93. Some limitation and pitfalls will also be introduced.   Detail PDF attached.    

Introduction LVGL is a graphics library to run on devices using a limited amount of resources. Previously, we have ran an LVGL demo from the LVGL repository, this contains a couple more demos which all of them are pieces of code included and lends us the opportunity to evaluate the library in a quick and easy way. GUI projects are developed by customers through a lot more options than bare code, there are GUI tools that translate a graphic asset into LVGL code, in this demonstration we will use a tool that's widely used in MCU GUI development and translate the GUI created into LVGL code; SquareLine. NOTE: refer to the appendix for precedent LVGL documents on i.MX series processors. HW set-up i.MX 93 EVK boot over eMMC/uSD to Linux Factory or Ubuntu. Connect power and debug receptables. Connect MX8_DSI_OLED1 to J701 (MIPI DSI) through MiniSAS cable. SquareLine set-up Download the latest version of SquareLine under the following link according to your host system. JosephAtNXP_0-1732571954892.png NOTE: This document is intended for demonstration of templates included within the tool, so it's recommended to download a free trial, for formal development please refer to the appendix of this document. Unzip and execute the installer, this is the windows prompt. JosephAtNXP_1-1732571954893.png   Demo download After setting SquareLine up go to the example section, we will demonstrate the thermostat capabilities with the Thermostat Demo. JosephAtNXP_2-1732571954894.png We can directly export these UI files and they would be graphically ready to be build, click on Export -> Export UI Files and select your preferred destination to save these. JosephAtNXP_3-1732571954894.png   LVGL setup. Option 1 Fresh Environment Clone LVGL and LV_DRIVERS repositories, this is a .gitmodules file that points to the specific branches needed. [submodule "lvgl"] path = lvgl url = https://github.com/lvgl/lvgl.git branch = release/v8.3 [submodule "lv_drivers"] path = lv_drivers url = https://github.com/lvgl/lv_drivers.git branch = release/v8.3 NOTE: If you are using other methods, you should point to these commits, lv_drivers @ 8cdabe8 and lvgl @ f2c1032. Gather the necessary files described below from the LVGL Linux Port example found here. Makefile lv_conf.h lv_drv_conf.h main.c mouse_cursor_icon.c Patch the Makefile. + include $(LVGL_DIR)/thermostat/thermostat.mk Patch the lv_drv_conf.h # define EVDEV_NAME "/dev/input/event10" /*You can use the "evtest" Linux tool to get the list of devices and test them*/ +# define EVDEV_NAME "/dev/input/event<Number>" NOTE: This changes according to the output of # evtest. Patch lv_conf.h -#define LV_FONT_MONTSERRAT_20 0 +#define LV_FONT_MONTSERRAT_20 1 Patch the main.c - disp_drv.hor_res = 800; - disp_drv.ver_res = 480; + disp_drv.hor_res = 1080; + disp_drv.ver_res = 1920; … - /*Create a Demo*/ - lv_demo_widgets(); + /*Create a Squareline Demo*/ + ui_init(); LVGL Setup. Option 2 with LVGL demos already running Gather the necessary files described below from the LVGL Linux Port example found here. Makefile lv_conf.h lv_drv_conf.h main.c mouse_cursor_icon.c Patch the lv_drv_conf.h # define EVDEV_NAME "/dev/input/event10" /*You can use the "evtest" Linux tool to get the list of devices and test them*/ +# define EVDEV_NAME "/dev/input/event<Number>" NOTE: This changes according to the output of # evtest. Patch the main.c - disp_drv.hor_res = 800; - disp_drv.ver_res = 480; + disp_drv.hor_res = 1080; + disp_drv.ver_res = 1920; … - /*Create a Demo*/ - lv_demo_widgets(); + /*Create a Squareline Demo*/ + ui_init(); Run the demo Build the demo with the following command and copy the ./demo output to the i.MX 93 EVK RootFS. # source /opt/path/to/your/toolchain # make clean # make The demo can be ran with the following commands. # systemctl stop weston # For LF $ sudo service gdm3 stop # For Ubuntu # ./demo JosephAtNXP_4-1732572830444.jpeg   Conclusion SquareLine demos can run in prebuilt and basic builds of i.MX processors through FB, which can enable a quick set-up for GUI testing before moving to use a windowing stack without sacrificing any features. Appendix Document: How to run LGVL on iMX using framebuffer Official page for pricing information