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products:sbc:vim2:configurations:user-config

VIM2 User Config File

The configuration file is only for Ubuntu system with Linux 4.9 and 5.15 kernel.

Introduction

This documentation will introduce how to use the configuration file of the Ubuntu system.

With kernel 4.9, env.txt is located in the /boot directory and is an environment configuration file used to configure the functions of the Ubuntu system. The system will read this file when it starts to set HDMI, fan, CPU frequency, etc.

With kernel 5.15, uEnv.txt is located in the /boot directory and is an environment configuration file used to configure the user bootargs.

If not mentioned, the configuration applies for both 4.9 and 5.15 Kernel.

HDMI Setting

This configuration is suitable for only the 4.9 kernel.

Auto Detect

The default setting is yes, it will automatically detect HDMI and set the best resolution, if it is set to no, you can set it manually:

# HDMI resolution auto detection
# yes - auto detection
# no  - set HDMI resolution via 'hdmi' node
hdmi_autodetect=yes

Disable auto detect:

hdmi_autodetect=no

HDMI Resolution Setting

In some situations HDMI resolution auto detect will not work, and you can try to setup the HDMI resolution manually.

Only when hdmi_autodetect=no, the changed configuration will take effect, the default is 720p.

Resolution Configuration
480×272 Progressive 60Hz hdmi=480x272p60hz
480×320 Progressive 60Hz hdmi=480x320p60hz
720×480 Progressive 60Hz hdmi=480p60hz
720×576 Progressive 50Hz hdmi=576p50hz
1280×720 Progressive 60Hz hdmi=720p60hz
1280×720 Progressive 50Hz hdmi=720p50hz
1920×1080 Progressive 60Hz hdmi=1080p60hz
1920×1080 Progressive 50Hz hdmi=1080p50hz
1920×1080 Progressive 30Hz hdmi=1080p30hz
1920×1080 Progressive 24Hz hdmi=1080p24hz
1920×1080 Interlaced 60Hz hdmi=1080i60hz
1920×1080 Interlaced 50Hz hdmi=1080i50hz
3840×2160 Progressive 60Hz hdmi=2160p60hz
3840×2160 Progressive 50Hz hdmi=2160p50hz
3840×2160 Progressive 30Hz hdmi=2160p30hz
3840×2160 Progressive 25Hz hdmi=2160p25hz
3840×2160 Progressive 24Hz hdmi=2160p24hz
3840×2160 Progressive 24Hz SMPTE hdmi=smpte24hz
3840×2160 Progressive 60Hz YCbCr 4:2:0 hdmi=2160p60hz420
3840×2160 Progressive 50Hz YCbCr 4:2:0 hdmi=2160p50hz420
640×480 Progressive 60Hz hdmi=640x480p60hz
800×480 Progressive 60Hz hdmi=800x480p60hz
800×600 Progressive 60Hz hdmi=800x600p60hz
1024×600 Progressive 60Hz hdmi=1024x600p60hz
1024×768 Progressive 60Hz hdmi=1024x768p60hz
1280×800 Progressive 60Hz hdmi=1280x800p60hz
1280×1024 Progressive 60Hz hdmi=1280x1024p60hz
1360×768 Progressive 60Hz hdmi=1360x768p60hz
1440×900 Progressive 60Hz hdmi=1440x900p60hz
1600×900 Progressive 60Hz hdmi=1600x900p60hz
1600×1200 Progressive 60Hz hdmi=1600x1200p60hz
1680×1050 Progressive 60Hz hdmi=1680x1050p60hz
1920×1200 Progressive 60Hz hdmi=1920x1200p60hz
2560×1080 Progressive 60Hz hdmi=2560x1080p60hz
2560×1440 Progressive 60Hz hdmi=2560x1440p60hz
2560×1600 Progressive 60Hz hdmi=2560x1600p60hz
3440×1440 Progressive 60Hz hdmi=3440x1440p60hz

Set to 1080p:

hdmi=1080p60hz

Save the file and reboot to take effect.

Fan Setting

Fan Level

  • off : Cooling fan is disabled.
  • low : Cooling fan is working at low speed mode.
  • mid : Cooling fan is working at middle speed mode.
  • high : Cooling fan is working at high speed mode.
  • auto : Cooling fan is working at auto speed mode. By default, the fan speed is determined by CPU temperature.

Change Fan Level

Fan level Configuration
off fan_mode=off
low fan_mode=low
mid fan_mode=mid
high fan_mode=high
auto fan_mode=auto

Set fan level to high:

fan_mode=high

Save the file and reboot to take effect.

Framebuffer Rotate Setting

This configuration is suitable for only the 4.9 kernel.

Check Framebuffer orientation

khadas@Khadas:~$ cat /boot/env.txt | grep "fb_rotate"
fb_rotate=0

Change Setting

Rotation Degrees Configuration
0 fb_rotate=0
90 fb_rotate=1
180 fb_rotate=2
270 fb_rotate=3

Rotate 90 degrees:

fb_rotate=1

Save the file and reboot to take effect.

Linux Kernel bootargs Setting

This configuration is suitable for only the 5.15 kernel.

Check Linux Kernel Bootargs

$ cat /proc/cmdline

Change Linux Kernel Bootargs

You can edit file /boot/uEnv.txt to add the user bootargs.

The default file contents are similar as below:

$ cat /boot/uEnv.txt 
#############################DO NOT TOUCH THIS OPTION#############################
rootdev=root=UUID=a92f7f2f-0d4a-4607-a45a-4549cfe71036
partitiontype=partition_type=generic
#############################DO NOT TOUCH THIS OPTION#############################
## Setup console
consoles=console=ttyS0,115200 console=tty0
 
## Setup FAN mode
fan_mode=auto
 
## Add user args here, spilt with space.
## e.g. Add bootargs 'test1=111 test2=222'
## boot_user_args=test1=111 test2=222
boot_user_args=

Normal Bootargs

You can append your bootargs to the configuration boot_user_args=.

e.g. Add bootargs cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory systemd.unified_cgroup_hierarchy=0, the variable boot_user_args= should be as below:

boot_user_args=cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory systemd.unified_cgroup_hierarchy=0

Console Bootargs

You can change the linux UART pins for normal usage by modifying the configuration console=

UART mode Configuration
Configure the UART for linux debug consoles=console=ttyS0,115200 console=tty0
Configure the UART for general usage consoles=console=tty0

eg. Enable linux UART console should be as below:

consoles=console=ttyS0,115200 console=tty0

Please make sure the bootargs are split with space and don't add quotation marks.

Save the file and reboot to take effect.

Saving the configurations

After edit the file, you need to save the file and reboot the board.

khadas@Khadas:~$ sync
khadas@Khadas:~$ sudo reboot
2022/09/07 02:44 · nick
Last modified: 2022/09/28 08:46 by nick