odroid-m1s:board_support:boot_sequence

Boot sequence

This stage is to fetch the bootloader from the boot medias (eMMC or SD card) and run to initiate the bare minimal peripherals. The firmware loaded in this stage is located at 64 LBA in a boot media. But when this stage is failed, it will switch to USB download mode that works with Rockchip's USB download tool.

  • eMMC : On-board (Supported capacity is listed in the product page)
  • SD card : Removable (UHS-I)
  • USB : Rockchip provide a tool to flash a bootloader to booting media above when RK3568 cannot fetch and run a bootloader.

The second stage is to load and run U-Boot and run boot script in order to start large operating system, and the operating system will be managed by a dedicated boot script. Supported boot scripts are:

This is a very common boot script type of U-Boot, it is a binary format with 64 bytes header at the beginning and its contents are consisted with U-Boot command set in order to run and start an operating system.

This file stores configurations to change a booting procedure or kernel parameters, it's been introduced to reduce the complexity from mixed U-Boot commands and configurations in lengthy boot.ini. Most common uses of this file is to select device tree overlay files.

One may want to add/remove/change a kernel parameter to affect the Linux kernel. Since /boot/boot.scr is a binary format with a certain header, it must not be changed by an editor.

There are two places to apply your changes to a boot script /boot/boot.scr.

/usr/share/flash-kernel/ubootenv.d/vendor

The contents of files in this directory are U-Boot commands and they will be included in /boot/boot.scr, kernel parameter must be added with command set env bootargs “${bootargs} YOUR-KERNEL-PARAMETER”.

/etc/default/flash-kernel

If you have something simple kernel parameter, add it to the line of LINUX_KERNEL_CMDLINE.

/boot/boot.scr will be updated with your change after running sudo update-bootscript and previous boot.scr will be backed up as boot.scr.bak.

U-Boot environment values will be stored in a dedicated area in in eMMC or SD card.

  • odroid-m1s/board_support/boot_sequence.txt
  • Last modified: 2023/11/21 12:20
  • by tobetter