§2023-08-26

¶ mkimage

• mkimage

The mkimage command is used to create images for use with the U-Boot boot loader. Thes eimages can contain the linux kernel, device tree blob, root file system image, firmware images etc., either separate or combined.

¶1. emerge -av u-boot-tools

(chroot) hc4Gentoo /boot # emerge -av u-boot-tools

 * IMPORTANT: 11 news items need reading for repository 'gentoo'.
 * Use eselect news read to view new items.


These are the packages that would be merged, in order:

Calculating dependencies... done!
Dependency resolution took 5.96 s.

[ebuild  N     ] dev-lang/swig-4.1.1-r1::gentoo  USE="pcre -ccache -doc -test" 8400 KiB
[ebuild  N     ] dev-embedded/u-boot-tools-2023.01::gentoo  USE="-envtools" 18126 KiB

Total: 2 packages (2 new), Size of downloads: 26525 KiB

Would you like to merge these packages? [Yes/No] yes

>>> Verifying ebuild manifests

>>> Emerging (1 of 2) dev-lang/swig-4.1.1-r1::gentoo
 * Fetching files in the background.
 * To view fetch progress, run in another terminal:
 * tail -f /var/log/emerge-fetch.log
....
--- /usr/bin/
>>> /usr/bin/fw_printenv
>>> /usr/bin/dumpimage
>>> /usr/bin/img2srec
>>> /usr/bin/bmp_logo
>>> /usr/bin/gen_eth_addr
>>> /usr/bin/mkenvimage
>>> /usr/bin/fw_setenv -> fw_printenv
>>> /usr/bin/fdtgrep
>>> /usr/bin/mkimage

¶ 2. `mkimage1

(chroot) hc4Gentoo /boot # pwd
/boot
(chroot) hc4Gentoo /boot # mkimage -A arm64 -O linux -T ramdisk -C none -a 0 -e 0 "Initramfs Image" -d initramfs-6.1.46-gentoo.img initramfs-6.1.46-gentoo.uimg
Image Name:   
Created:      Sun Aug 27 11:34:52 2023
Image Type:   AArch64 Linux RAMDisk Image (uncompressed)
Data Size:    5770132 Bytes = 5634.89 KiB = 5.50 MiB
Load Address: 00000000
Entry Point:  00000000
(chroot) hc4Gentoo /boot # ls
'Initramfs Image'   initramfs-6.1.46-gentoo.img

¶Description

The mkimage command is used to create images for use with the U-Boot boot loader. Thes eimages can contain the linux kernel, device tree blob, root file system image, firmware images etc., either separate or combined.

mkimage supports two different formats:

• The old, legacy image format concatenates the individual parts (for example, kernel image, device tree blob and ramdisk image) and adds a 64 bytes header containing information about target architecture, operating system, image type, compression method, entry points, time stamp, checksums, etc.
• The new, FIT (Flattened Image Tree) format allows for more flexibility in handling images of various and also enhances integrity protection of images with stronger checksums.

For Example: mkimage -A arm64 -O linux -T ramdisk -C none -a 0x4080000 -e 0x1080000 -n "Initramfs Image" -d initramfs.img initramfs.img.uimg

-a 0, -e 0 for odroid

Options List image information:

-l [uimage file name] mkimage lists the information contained in the header of an existing U-Boot image. Create old legacy image:

-A [architecture] Set architecture. Pass -A -h as the architecture to see the list of supported architectures. -O [os] Set operating system. bootm command of u-boot changes boot method by os type. Pass -h as the OS to see the list of supported OS. -T [image type] Set image type. Pass -T -h as the image to see the list of supported image type. -C [compression type] Set compression type. Pass -h as the compression to see the list of supported compression type. -a [load addess] Set load address with a hex number. -e [entry point] Set entry point with a hex number. -n [image name] Set image name to 'image name'. -d [image data file] Use image data from 'image data file'. -x Set XIP (execute in place) flag. Create FIT image:

-D dtcoption" Provide special options to the device tree compiler that is used to create the image. -f fit-image.its" Image tree source fine that descbres the structure and contents of the FIT image.

• in my boot.ini

ODROIDC4-UBOOT-CONFIG

# Default Console Device Setting
setenv condev "console=ttyAML0,115200n8"   # on both

# setenv bootlabel
setenv bootlabel "2023-08-26 From Manjaro-arm-installer To Gentoo"

# Boot Args
setenv bootargs "root=PARTUUID=69ed71c7-03 rootwait rw ${condev} ${amlogic} no_console_suspend fsck.repair=yes net.ifnames=0 clk_ignore_unused quiet splash plymouth.ignore-serial-consoles"

# Set load addresses
setenv dtb_loadaddr "0x20000000"
setenv loadaddr "0x1080000"
setenv initrd_loadaddr "0x4080000"

# Load kernel, dtb and initrd
load mmc ${devno}:1 ${loadaddr} /Image
load mmc ${devno}:1 ${dtb_loadaddr} /dtbs/amlogic/meson-sm1-odroid-hc4.dtb
load mmc ${devno}:1 ${initrd_loadaddr} /initramfs-linux.uimg
#fdt addr ${dtb_loadaddr}

# boot
booti ${loadaddr} ${initrd_loadaddr} ${dtb_loadaddr}

And my /boot/Image is my image file, what will be my initramfs.img.uimg for U-boot using mkimage?