| .TH MKIMAGE 1 "2010-05-16" | |
| .SH NAME | |
| mkimage \- Generate image for U-Boot | |
| .SH SYNOPSIS | |
| .B mkimage | |
| .RB "\-l [" "uimage file name" "]" | |
| .B mkimage | |
| .RB [\fIoptions\fP] " \-f [" "image tree source file" "]" " [" "uimage file name" "]" | |
| .B mkimage | |
| .RB [\fIoptions\fP] " \-F [" "uimage file name" "]" | |
| .B mkimage | |
| .RB [\fIoptions\fP] " (legacy mode)" | |
| .SH "DESCRIPTION" | |
| The | |
| .B mkimage | |
| command is used to create images for use with the U-Boot boot loader. | |
| These images can contain the linux kernel, device tree blob, root file | |
| system image, firmware images etc., either separate or combined. | |
| .B mkimage | |
| supports two different formats: | |
| The old | |
| .I 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 | |
| .I FIT (Flattened Image Tree) format | |
| allows for more flexibility in handling images of various types and also | |
| enhances integrity protection of images with stronger checksums. It also | |
| supports verified boot. | |
| .SH "OPTIONS" | |
| .B List image information: | |
| .TP | |
| .BI "\-l [" "uimage file name" "]" | |
| mkimage lists the information contained in the header of an existing U-Boot image. | |
| .P | |
| .B Create old legacy image: | |
| .TP | |
| .BI "\-A [" "architecture" "]" | |
| Set architecture. Pass \-h as the architecture to see the list of supported architectures. | |
| .TP | |
| .BI "\-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. | |
| .TP | |
| .BI "\-T [" "image type" "]" | |
| Set image type. | |
| Pass \-h as the image to see the list of supported image type. | |
| .TP | |
| .BI "\-C [" "compression type" "]" | |
| Set compression type. | |
| Pass \-h as the compression to see the list of supported compression type. | |
| .TP | |
| .BI "\-a [" "load address" "]" | |
| Set load address with a hex number. | |
| .TP | |
| .BI "\-e [" "entry point" "]" | |
| Set entry point with a hex number. | |
| .TP | |
| .BI "\-l" | |
| List the contents of an image. | |
| .TP | |
| .BI "\-n [" "image name" "]" | |
| Set image name to 'image name'. | |
| .TP | |
| .BI "\-d [" "image data file" "]" | |
| Use image data from 'image data file'. | |
| .TP | |
| .BI "\-x" | |
| Set XIP (execute in place) flag. | |
| .P | |
| .B Create FIT image: | |
| .TP | |
| .BI "\-b [" "device tree file" "] | |
| Appends the device tree binary file (.dtb) to the FIT. | |
| .TP | |
| .BI "\-c [" "comment" "]" | |
| Specifies a comment to be added when signing. This is typically a useful | |
| message which describes how the image was signed or some other useful | |
| information. | |
| .TP | |
| .BI "\-D [" "dtc options" "]" | |
| Provide special options to the device tree compiler that is used to | |
| create the image. | |
| .TP | |
| .BI "\-E | |
| After processing, move the image data outside the FIT and store a data offset | |
| in the FIT. Images will be placed one after the other immediately after the | |
| FIT, with each one aligned to a 4-byte boundary. The existing 'data' property | |
| in each image will be replaced with 'data-offset' and 'data-size' properties. | |
| A 'data-offset' of 0 indicates that it starts in the first (4-byte aligned) | |
| byte after the FIT. | |
| .TP | |
| .BI "\-f [" "image tree source file" " | " "auto" "]" | |
| Image tree source file that describes the structure and contents of the | |
| FIT image. | |
| This can be automatically generated for some simple cases. | |
| Use "-f auto" for this. In that case the arguments -d, -A, -O, -T, -C, -a | |
| and -e are used to specify the image to include in the FIT and its attributes. | |
| No .its file is required. | |
| .TP | |
| .BI "\-F" | |
| Indicates that an existing FIT image should be modified. No dtc | |
| compilation is performed and the \-f flag should not be given. | |
| This can be used to sign images with additional keys after initial image | |
| creation. | |
| .TP | |
| .BI "\-k [" "key_directory" "]" | |
| Specifies the directory containing keys to use for signing. This directory | |
| should contain a private key file <name>.key for use with signing and a | |
| certificate <name>.crt (containing the public key) for use with verification. | |
| .TP | |
| .BI "\-K [" "key_destination" "]" | |
| Specifies a compiled device tree binary file (typically .dtb) to write | |
| public key information into. When a private key is used to sign an image, | |
| the corresponding public key is written into this file for for run-time | |
| verification. Typically the file here is the device tree binary used by | |
| CONFIG_OF_CONTROL in U-Boot. | |
| .TP | |
| .BI "\-p [" "external position" "]" | |
| Place external data at a static external position. See \-E. Instead of writing | |
| a 'data-offset' property defining the offset from the end of the FIT, \-p will | |
| use 'data-position' as the absolute position from the base of the FIT. | |
| .TP | |
| .BI "\-r | |
| Specifies that keys used to sign the FIT are required. This means that they | |
| must be verified for the image to boot. Without this option, the verification | |
| will be optional (useful for testing but not for release). | |
| .SH EXAMPLES | |
| List image information: | |
| .nf | |
| .B mkimage -l uImage | |
| .fi | |
| .P | |
| Create legacy image with compressed PowerPC Linux kernel: | |
| .nf | |
| .B mkimage -A powerpc -O linux -T kernel -C gzip \\\\ | |
| .br | |
| .B -a 0 -e 0 -n Linux -d vmlinux.gz uImage | |
| .fi | |
| .P | |
| Create FIT image with compressed PowerPC Linux kernel: | |
| .nf | |
| .B mkimage -f kernel.its kernel.itb | |
| .fi | |
| .P | |
| Create FIT image with compressed kernel and sign it with keys in the | |
| /public/signing-keys directory. Add corresponding public keys into u-boot.dtb, | |
| skipping those for which keys cannot be found. Also add a comment. | |
| .nf | |
| .B mkimage -f kernel.its -k /public/signing-keys -K u-boot.dtb \\\\ | |
| .br | |
| .B -c """Kernel 3.8 image for production devices""" kernel.itb | |
| .fi | |
| .P | |
| Update an existing FIT image, signing it with additional keys. | |
| Add corresponding public keys into u-boot.dtb. This will resign all images | |
| with keys that are available in the new directory. Images that request signing | |
| with unavailable keys are skipped. | |
| .nf | |
| .B mkimage -F -k /secret/signing-keys -K u-boot.dtb \\\\ | |
| .br | |
| .B -c """Kernel 3.8 image for production devices""" kernel.itb | |
| .fi | |
| .P | |
| Create a FIT image containing a kernel, using automatic mode. No .its file | |
| is required. | |
| .nf | |
| .B mkimage -f auto -A arm -O linux -T kernel -C none -a 43e00000 -e 0 \\\\ | |
| .br | |
| .B -c """Kernel 4.4 image for production devices""" -d vmlinuz kernel.itb | |
| .fi | |
| .P | |
| Create a FIT image containing a kernel and some device tree files, using | |
| automatic mode. No .its file is required. | |
| .nf | |
| .B mkimage -f auto -A arm -O linux -T kernel -C none -a 43e00000 -e 0 \\\\ | |
| .br | |
| .B -c """Kernel 4.4 image for production devices""" -d vmlinuz \\\\ | |
| .B -b /path/to/rk3288-firefly.dtb -b /path/to/rk3288-jerry.dtb kernel.itb | |
| .fi | |
| .SH HOMEPAGE | |
| http://www.denx.de/wiki/U-Boot/WebHome | |
| .PP | |
| .SH AUTHOR | |
| This manual page was written by Nobuhiro Iwamatsu <iwamatsu@nigauri.org> | |
| and Wolfgang Denk <wd@denx.de>. It was updated for image signing by | |
| Simon Glass <sjg@chromium.org>. |