doc/mkimage.1 - filogic/uboot - Gitiles

 .TH MKIMAGE 1 "2022-02-07"
 .
 .SH NAME
 mkimage \- generate images for U-Boot
 .SH SYNOPSIS
 .SY mkimage
 .OP \-T type
 .BI \-l\~ image-file-name
 .YS
 .
 .SY mkimage
 .RI [ option\~ .\|.\|.\&]
 .OP \-T type
 .I image-file-name
 .YS
 .
 .SY mkimage
 .RI [ option\~ .\|.\|.\&]
 .BI \-f\~ image-tree-source-file\c
 .RB | auto
 .I image-file-name
 .YS
 .
 .SY mkimage
 .RI [ option\~ .\|.\|.\&]
 .BI \-F\~ image-file-name
 .YS
 .
 .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.
 .P
 .B mkimage
 supports many image formats. Some of these formats may be used by embedded boot
 firmware to load U-Boot. Others may be used by U-Boot to load Linux (or some
 other kernel):
 .P
 The legacy image format concatenates the individual parts (for example, kernel
 image, device tree blob and ramdisk image) and adds a 64 byte header containing
 information about the target architecture, operating system, image type,
 compression method, entry points, time stamp, checksums, etc.
 .P
 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
 .
 .SS General options
 .
 .TP
 .B \-h
 Print a help message and exit.
 .
 .TP
 .B \-l
 .B mkimage
 lists the information contained in the header of an existing U-Boot image.
 .
 .TP
 .B \-s
 Don't copy in the image data. Depending on the image type, this may create
 just the header, everything but the image data, or nothing at all.
 .
 .TP
 .BI \-T " image-type"
 Parse image file as
 .IR image-type .
 Pass
 .B list
 as
 .I image-type
 to see the list of supported image types. If this option is absent, then it
 defaults to
 .B kernel
 (legacy image). If this option is absent when
 .B \-l
 is passed, then
 .B mkimage
 will attempt to automatically detect the image type. Not all image types support
 automatic detection, so it may be necessary to pass
 .B \-T
 explicitly.
 .IP
 When creating a FIT image with
 .BR \-f ,
 the image type is always set to
 .BR flat_dt .
 In this case,
 .B \-T
 specifies the image node's \(oqtype\(cq property. If
 .B \-T
 is absent, then the \(oqtype\(cq property will default to
 .BR kernel .
 .
 .TP
 .B \-q
 Quiet. Don't print the image header.
 .
 .TP
 .B \-v
 Verbose. Print file names as they are added to the image.
 .
 .TP
 .B \-V
 Print version information and exit.
 .
 .SS General image-creation options
 .
 .TP
 .BI \-A " architecture"
 Set the architecture. Pass
 .B \-h
 as the architecture to see the list of supported architectures. If
 .B \-A
 is absent, it defaults to
 .BR ppc .
 .
 .TP
 .BI \-O " os"
 Set the operating system. The U-Boot
 .I bootm
 command changes boot method based on the OS type.
 Pass
 .B \-h
 as the
 .I os
 to see the list of supported OSs. If
 .B \-O
 is absent, it defaults to
 .BR linux .
 .
 .TP
 .BI \-C " compression-type"
 Set the compression type. The image data should have already been compressed
 using this compression type.
 .B mkimage
 will not automatically compress image data.
 Pass
 .B \-h
 as the
 .I compression-type
 to see the list of supported compression types. If
 .B \-C
 is absent, it defaults to
 .BR gzip .
 .
 .TP
 .BI \-a " load-address"
 Set the absolute address to load the image data to.
 .I load-address
 will be interpreted as a hexadecimal number.
 .
 .TP
 .BI \-e " entry-point"
 Set the absolute address of the image entry point. The U-Boot
 .I bootm
 command will jump to this address after loading the image.
 .I entry-point
 will be interpreted as a hexadecimal number.
 .
 .TP
 .BI \-n " image-name"
 Set the image name to
 .IR image-name .
 .
 .TP
 .BI \-R " secondary-image-name"
 Some image types support a second image for additional data. For these types,
 use
 .B \-R
 to specify this second image.
 .TS
 allbox;
 lb lbx
 l l.
 Image Type	Secondary Image Description
 pblimage	Additional RCW-style header, typically used for PBI commands.
 zynqimage, zynqmpimage	T{
 Initialization parameters, one per line. Each parameter has the form
 .sp
 .ti 4
 .I address data
 .sp
 where
 .I address
 and
 .I data
 are hexadecimal integers. The boot ROM will write each
 .I data
 to
 .I address
 when loading the image. At most 256 parameters may be specified in this
 manner.
 T}
 .TE
 .
 .TP
 .BI \-d " image-data-file"
 Use image data from
 .IR image-data-file .
 If the
 .I image-type
 is
 .BR multi ,
 then multiple images may be specified, separated by colons:
 .RS
 .IP
 .IR image-data-file [\fB:\fP image-data-file .\|.\|.]
 .RE
 .
 .TP
 .B \-x
 Set the
 .I XIP
 (execute in place) flag. The U-Boot
 .I bootm
 command will not load the image data, and instead will assume it is already
 accessible at the load address (such as via memory-mapped flash).
 .
 .SS Options for creating FIT images
 .
 .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 message which
 describes how the image was signed or some other useful information.
 .
 .TP
 .BI \-D " dtc-options"
 Provide additional options to the device tree compiler when creating the image.
 See
 .BR dtc (1)
 for documentation of possible options. If
 .B \-D
 is absent, it defaults to
 .BR "\-I dts \-O dtb \-p 500" .
 .
 .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 \(oqdata\(cq property
 in each image will be replaced with \(oqdata-offset\(cq and \(oqdata-size\(cq
 properties.  A \(oqdata-offset\(cq of 0 indicates that it starts in the first
 (4-byte-aligned) byte after the FIT.
 .
 .TP
 .BI \-B " alignment"
 The alignment, in hexadecimal, that external data will be aligned to. This
 option only has an effect when \-E is specified.
 .
 .TP
 .BI \-p " external-position"
 Place external data at a static external position. Instead of writing a
 \(oqdata-offset\(cq property defining the offset from the end of the FIT,
 .B \-p
 will use \(oqdata-position\(cq as the absolute position from the base of the
 FIT. See
 .B \-E
 for details on using external data.
 .
 .TP
 \fB\-f \fIimage-tree-source-file\fR | \fBauto
 Image tree source file that describes the structure and contents of the
 FIT image.
 .IP
 In some simple cases, the image tree source can be generated automatically. To
 use this feature, pass
 .BR "\-f auto" .
 The
 .BR \-d ,
 .BR \-A ,
 .BR \-O ,
 .BR \-T ,
 .BR \-C ,
 .BR \-a ,
 and
 .B \-e
 options may be used to specify the image to include in the FIT and its
 attributes. No
 .I image-tree-source-file
 is required.
 .
 .TP
 .B \-F
 Indicates that an existing FIT image should be modified. No dtc compilation will
 be performed and
 .B \-f
 should not be passed. This can be used to sign images with additional keys
 after initial image creation.
 .
 .TP
 .BI \-i " ramdisk-file"
 Append a ramdisk or initramfs file to the image.
 .
 .TP
 .BI \-k " key-directory"
 Specifies the directory containing keys to use for signing. This directory
 should contain a private key file
 .IR name .key
 for use with signing, and a certificate
 .IR name .crt
 (containing the public key) for use with verification. The public key is only
 necessary when embedding it into another device tree using
 .BR \-K .
 .I name
 defaults to the value of the signature node's \(oqkey-name-hint\(cq property,
 but may be overridden using
 .BR \-g .
 .
 .TP
 .BI \-G " key-file"
 Specifies the private key file to use when signing. This option may be used
 instead of \-k.
 .
 .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 \-g " key-name-hint"
 Overrides the signature node's \(oqkey-name-hint\(cq property. This is
 especially useful when signing an image with
 .BR "\-f auto" .
 This is the
 .I name
 part of the key. The directory part is set by
 .BR \-k .
 This option also indicates that the images included in the FIT should be signed.
 If this option is specified, then
 .B \-o
 must be specified as well.
 .
 .TP
 .BI \-o " crypto" , checksum
 Specifies the algorithm to be used for signing a FIT image. The default is
 taken from the signature node's \(oqalgo\(cq property.
 The valid values for
 .I crypto
 are:
 .RS
 .IP
 .TS
 lb.
 rsa2048
 rsa3072
 rsa4096
 ecdsa256
 .TE
 .RE
 .IP
 The valid values for
 .I checksum
 are
 .RS
 .IP
 .TS
 lb.
 sha1
 sha256
 sha384
 sha512
 .TE
 .RE
 .
 .TP
 .B \-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).
 .
 .TP
 .BI \-N " engine"
 The openssl engine to use when signing and verifying the image. For a complete
 list of available engines, refer to
 .BR engine (1).
 .
 .TP
 .B \-t
 Update the timestamp in the FIT.
 .IP
 Normally the FIT timestamp is created the first time mkimage runs,
 when converting the source .its to the binary .fit file. This corresponds to
 using
 .BR -f .
 But if the original input to mkimage is a binary file (already compiled), then
 the timestamp is assumed to have been set previously.
 .
 .SH EXAMPLES
 .\" Reduce the width of the tab stops to something reasonable
 .ta T 1i
 List image information:
 .RS
 .P
 .EX
 \fBmkimage \-l uImage
 .EE
 .RE
 .P
 Create legacy image with compressed PowerPC Linux kernel:
 .RS
 .P
 .EX
 \fBmkimage \-A powerpc \-O linux \-T kernel \-C gzip \\
 	\-a 0 \-e 0 \-n Linux \-d vmlinux.gz uImage
 .EE
 .RE
 .P
 Create FIT image with compressed PowerPC Linux kernel:
 .RS
 .P
 .EX
 \fBmkimage \-f kernel.its kernel.itb
 .EE
 .RE
 .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.
 .RS
 .P
 .EX
 \fBmkimage \-f kernel.its \-k /public/signing\-keys \-K u\-boot.dtb \\
 	\-c \(dqKernel 3.8 image for production devices\(dq kernel.itb
 .EE
 .RE
 .P
 Add public keys to u\-boot.dtb without needing a FIT to sign. This will also
 create a FIT containing an images node with no data named unused.itb.
 .RS
 .P
 .EX
 \fBmkimage \-f auto \-d /dev/null \-k /public/signing\-keys \-g dev \\
 	\-o sha256,rsa2048 \-K u\-boot.dtb unused.itb
 .EE
 .RE
 .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.
 .RS
 .P
 .EX
 \fBmkimage \-F \-k /secret/signing\-keys \-K u\-boot.dtb \\
 	\-c \(dqKernel 3.8 image for production devices\(dq kernel.itb
 .EE
 .RE
 .P
 Create a FIT image containing a kernel, using automatic mode. No .its file
 is required.
 .RS
 .P
 .EX
 \fBmkimage \-f auto \-A arm \-O linux \-T kernel \-C none \-a 43e00000 \-e 0 \\
 	\-c \(dqKernel 4.4 image for production devices\(dq \-d vmlinuz kernel.itb
 .EE
 .RE
 .P
 Create a FIT image containing a kernel and some device tree files, using
 automatic mode. No .its file is required.
 .RS
 .P
 .EX
 \fBmkimage \-f auto \-A arm \-O linux \-T kernel \-C none \-a 43e00000 \-e 0 \\
 	\-c \(dqKernel 4.4 image for production devices\(dq \-d vmlinuz \\
 	\-b /path/to/rk3288\-firefly.dtb \-b /path/to/rk3288\-jerry.dtb kernel.itb
 .EE
 .RE
 .P
 Create a FIT image containing a signed kernel, using automatic mode. No .its
 file is required.
 .RS
 .P
 .EX
 \fBmkimage \-f auto \-A arm \-O linux \-T kernel \-C none \-a 43e00000 \-e 0 \\
 	\-d vmlinuz \-k /secret/signing\-keys \-g dev \-o sha256,rsa2048 kernel.itb
 .EE
 .RE
 .
 .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>.
	.TH MKIMAGE 1 "2022-02-07"
	.
	.SH NAME
	mkimage \- generate images for U-Boot
	.SH SYNOPSIS
	.SY mkimage
	.OP \-T type
	.BI \-l\~ image-file-name
	.YS
	.
	.SY mkimage
	.RI [ option\~ .\\|.\\|.\&]
	.OP \-T type
	.I image-file-name
	.YS
	.
	.SY mkimage
	.RI [ option\~ .\\|.\\|.\&]
	.BI \-f\~ image-tree-source-file\c
	.RB \| auto
	.I image-file-name
	.YS
	.
	.SY mkimage
	.RI [ option\~ .\\|.\\|.\&]
	.BI \-F\~ image-file-name
	.YS
	.
	.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.
	.P
	.B mkimage
	supports many image formats. Some of these formats may be used by embedded boot
	firmware to load U-Boot. Others may be used by U-Boot to load Linux (or some
	other kernel):
	.P
	The legacy image format concatenates the individual parts (for example, kernel
	image, device tree blob and ramdisk image) and adds a 64 byte header containing
	information about the target architecture, operating system, image type,
	compression method, entry points, time stamp, checksums, etc.
	.P
	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
	.
	.SS General options
	.
	.TP
	.B \-h
	Print a help message and exit.
	.
	.TP
	.B \-l
	.B mkimage
	lists the information contained in the header of an existing U-Boot image.
	.
	.TP
	.B \-s
	Don't copy in the image data. Depending on the image type, this may create
	just the header, everything but the image data, or nothing at all.
	.
	.TP
	.BI \-T " image-type"
	Parse image file as
	.IR image-type .
	Pass
	.B list
	as
	.I image-type
	to see the list of supported image types. If this option is absent, then it
	defaults to
	.B kernel
	(legacy image). If this option is absent when
	.B \-l
	is passed, then
	.B mkimage
	will attempt to automatically detect the image type. Not all image types support
	automatic detection, so it may be necessary to pass
	.B \-T
	explicitly.
	.IP
	When creating a FIT image with
	.BR \-f ,
	the image type is always set to
	.BR flat_dt .
	In this case,
	.B \-T
	specifies the image node's \(oqtype\(cq property. If
	.B \-T
	is absent, then the \(oqtype\(cq property will default to
	.BR kernel .
	.
	.TP
	.B \-q
	Quiet. Don't print the image header.
	.
	.TP
	.B \-v
	Verbose. Print file names as they are added to the image.
	.
	.TP
	.B \-V
	Print version information and exit.
	.
	.SS General image-creation options
	.
	.TP
	.BI \-A " architecture"
	Set the architecture. Pass
	.B \-h
	as the architecture to see the list of supported architectures. If
	.B \-A
	is absent, it defaults to
	.BR ppc .
	.
	.TP
	.BI \-O " os"
	Set the operating system. The U-Boot
	.I bootm
	command changes boot method based on the OS type.
	Pass
	.B \-h
	as the
	.I os
	to see the list of supported OSs. If
	.B \-O
	is absent, it defaults to
	.BR linux .
	.
	.TP
	.BI \-C " compression-type"
	Set the compression type. The image data should have already been compressed
	using this compression type.
	.B mkimage
	will not automatically compress image data.
	Pass
	.B \-h
	as the
	.I compression-type
	to see the list of supported compression types. If
	.B \-C
	is absent, it defaults to
	.BR gzip .
	.
	.TP
	.BI \-a " load-address"
	Set the absolute address to load the image data to.
	.I load-address
	will be interpreted as a hexadecimal number.
	.
	.TP
	.BI \-e " entry-point"
	Set the absolute address of the image entry point. The U-Boot
	.I bootm
	command will jump to this address after loading the image.
	.I entry-point
	will be interpreted as a hexadecimal number.
	.
	.TP
	.BI \-n " image-name"
	Set the image name to
	.IR image-name .
	.
	.TP
	.BI \-R " secondary-image-name"
	Some image types support a second image for additional data. For these types,
	use
	.B \-R
	to specify this second image.
	.TS
	allbox;
	lb lbx
	l l.
	Image Type Secondary Image Description
	pblimage Additional RCW-style header, typically used for PBI commands.
	zynqimage, zynqmpimage T{
	Initialization parameters, one per line. Each parameter has the form
	.sp
	.ti 4
	.I address data
	.sp
	where
	.I address
	and
	.I data
	are hexadecimal integers. The boot ROM will write each
	.I data
	to
	.I address
	when loading the image. At most 256 parameters may be specified in this
	manner.
	T}
	.TE
	.
	.TP
	.BI \-d " image-data-file"
	Use image data from
	.IR image-data-file .
	If the
	.I image-type
	is
	.BR multi ,
	then multiple images may be specified, separated by colons:
	.RS
	.IP
	.IR image-data-file [\fB:\fP image-data-file .\\|.\\|.]
	.RE
	.
	.TP
	.B \-x
	Set the
	.I XIP
	(execute in place) flag. The U-Boot
	.I bootm
	command will not load the image data, and instead will assume it is already
	accessible at the load address (such as via memory-mapped flash).
	.
	.SS Options for creating FIT images
	.
	.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 message which
	describes how the image was signed or some other useful information.
	.
	.TP
	.BI \-D " dtc-options"
	Provide additional options to the device tree compiler when creating the image.
	See
	.BR dtc (1)
	for documentation of possible options. If
	.B \-D
	is absent, it defaults to
	.BR "\-I dts \-O dtb \-p 500" .
	.
	.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 \(oqdata\(cq property
	in each image will be replaced with \(oqdata-offset\(cq and \(oqdata-size\(cq
	properties. A \(oqdata-offset\(cq of 0 indicates that it starts in the first
	(4-byte-aligned) byte after the FIT.
	.
	.TP
	.BI \-B " alignment"
	The alignment, in hexadecimal, that external data will be aligned to. This
	option only has an effect when \-E is specified.
	.
	.TP
	.BI \-p " external-position"
	Place external data at a static external position. Instead of writing a
	\(oqdata-offset\(cq property defining the offset from the end of the FIT,
	.B \-p
	will use \(oqdata-position\(cq as the absolute position from the base of the
	FIT. See
	.B \-E
	for details on using external data.
	.
	.TP
	\fB\-f \fIimage-tree-source-file\fR \| \fBauto
	Image tree source file that describes the structure and contents of the
	FIT image.
	.IP
	In some simple cases, the image tree source can be generated automatically. To
	use this feature, pass
	.BR "\-f auto" .
	The
	.BR \-d ,
	.BR \-A ,
	.BR \-O ,
	.BR \-T ,
	.BR \-C ,
	.BR \-a ,
	and
	.B \-e
	options may be used to specify the image to include in the FIT and its
	attributes. No
	.I image-tree-source-file
	is required.
	.
	.TP
	.B \-F
	Indicates that an existing FIT image should be modified. No dtc compilation will
	be performed and
	.B \-f
	should not be passed. This can be used to sign images with additional keys
	after initial image creation.
	.
	.TP
	.BI \-i " ramdisk-file"
	Append a ramdisk or initramfs file to the image.
	.
	.TP
	.BI \-k " key-directory"
	Specifies the directory containing keys to use for signing. This directory
	should contain a private key file
	.IR name .key
	for use with signing, and a certificate
	.IR name .crt
	(containing the public key) for use with verification. The public key is only
	necessary when embedding it into another device tree using
	.BR \-K .
	.I name
	defaults to the value of the signature node's \(oqkey-name-hint\(cq property,
	but may be overridden using
	.BR \-g .
	.
	.TP
	.BI \-G " key-file"
	Specifies the private key file to use when signing. This option may be used
	instead of \-k.
	.
	.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 \-g " key-name-hint"
	Overrides the signature node's \(oqkey-name-hint\(cq property. This is
	especially useful when signing an image with
	.BR "\-f auto" .
	This is the
	.I name
	part of the key. The directory part is set by
	.BR \-k .
	This option also indicates that the images included in the FIT should be signed.
	If this option is specified, then
	.B \-o
	must be specified as well.
	.
	.TP
	.BI \-o " crypto" , checksum
	Specifies the algorithm to be used for signing a FIT image. The default is
	taken from the signature node's \(oqalgo\(cq property.
	The valid values for
	.I crypto
	are:
	.RS
	.IP
	.TS
	lb.
	rsa2048
	rsa3072
	rsa4096
	ecdsa256
	.TE
	.RE
	.IP
	The valid values for
	.I checksum
	are
	.RS
	.IP
	.TS
	lb.
	sha1
	sha256
	sha384
	sha512
	.TE
	.RE
	.
	.TP
	.B \-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).
	.
	.TP
	.BI \-N " engine"
	The openssl engine to use when signing and verifying the image. For a complete
	list of available engines, refer to
	.BR engine (1).
	.
	.TP
	.B \-t
	Update the timestamp in the FIT.
	.IP
	Normally the FIT timestamp is created the first time mkimage runs,
	when converting the source .its to the binary .fit file. This corresponds to
	using
	.BR -f .
	But if the original input to mkimage is a binary file (already compiled), then
	the timestamp is assumed to have been set previously.
	.
	.SH EXAMPLES
	.\" Reduce the width of the tab stops to something reasonable
	.ta T 1i
	List image information:
	.RS
	.P
	.EX
	\fBmkimage \-l uImage
	.EE
	.RE
	.P
	Create legacy image with compressed PowerPC Linux kernel:
	.RS
	.P
	.EX
	\fBmkimage \-A powerpc \-O linux \-T kernel \-C gzip \\
	\-a 0 \-e 0 \-n Linux \-d vmlinux.gz uImage
	.EE
	.RE
	.P
	Create FIT image with compressed PowerPC Linux kernel:
	.RS
	.P
	.EX
	\fBmkimage \-f kernel.its kernel.itb
	.EE
	.RE
	.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.
	.RS
	.P
	.EX
	\fBmkimage \-f kernel.its \-k /public/signing\-keys \-K u\-boot.dtb \\
	\-c \(dqKernel 3.8 image for production devices\(dq kernel.itb
	.EE
	.RE
	.P
	Add public keys to u\-boot.dtb without needing a FIT to sign. This will also
	create a FIT containing an images node with no data named unused.itb.
	.RS
	.P
	.EX
	\fBmkimage \-f auto \-d /dev/null \-k /public/signing\-keys \-g dev \\
	\-o sha256,rsa2048 \-K u\-boot.dtb unused.itb
	.EE
	.RE
	.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.
	.RS
	.P
	.EX
	\fBmkimage \-F \-k /secret/signing\-keys \-K u\-boot.dtb \\
	\-c \(dqKernel 3.8 image for production devices\(dq kernel.itb
	.EE
	.RE
	.P
	Create a FIT image containing a kernel, using automatic mode. No .its file
	is required.
	.RS
	.P
	.EX
	\fBmkimage \-f auto \-A arm \-O linux \-T kernel \-C none \-a 43e00000 \-e 0 \\
	\-c \(dqKernel 4.4 image for production devices\(dq \-d vmlinuz kernel.itb
	.EE
	.RE
	.P
	Create a FIT image containing a kernel and some device tree files, using
	automatic mode. No .its file is required.
	.RS
	.P
	.EX
	\fBmkimage \-f auto \-A arm \-O linux \-T kernel \-C none \-a 43e00000 \-e 0 \\
	\-c \(dqKernel 4.4 image for production devices\(dq \-d vmlinuz \\
	\-b /path/to/rk3288\-firefly.dtb \-b /path/to/rk3288\-jerry.dtb kernel.itb
	.EE
	.RE
	.P
	Create a FIT image containing a signed kernel, using automatic mode. No .its
	file is required.
	.RS
	.P
	.EX
	\fBmkimage \-f auto \-A arm \-O linux \-T kernel \-C none \-a 43e00000 \-e 0 \\
	\-d vmlinuz \-k /secret/signing\-keys \-g dev \-o sha256,rsa2048 kernel.itb
	.EE
	.RE
	.
	.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>.