(mkimage) is invoked directly. dtc is called from within mkimage and operates
behind the scenes, but needs to be present in the $PATH nevertheless. It is
important that the dtc used has support for binary includes -- refer to
-www.jdl.com for its latest version. mkimage (together with dtc) takes as input
+
+ git://git.kernel.org/pub/scm/utils/dtc/dtc.git
+
+for its latest version. mkimage (together with dtc) takes as input
an image source file, which describes the contents of the image and defines
its various properties used during booting. By convention, image source file
has the ".its" extension, also, the details of its format are given in
-doc/source_file_format.txt. The actual data that is to be included in the
-uImage (kernel, ramdisk, etc.) is specified in the image source file in the
+doc/uImage.FIT/source_file_format.txt. The actual data that is to be included in
+the uImage (kernel, ramdisk, etc.) is specified in the image source file in the
form of paths to appropriate data files. The outcome of the image creation
process is a binary file (by convention with the ".itb" extension) that
contains all the referenced data (kernel, ramdisk, etc.) and other information
image source file mkimage + dtc transfer to target
+ ---------------> image file --------------------> bootm
-image data files(s)
+image data file(s)
+
+SPL usage
+---------
+
+The SPL can make use of the new image format as well, this traditionally
+is used to ship multiple device tree files within one image. Code in the SPL
+will choose the one matching the current board and append this to the
+U-Boot proper binary to be automatically used up by it.
+Aside from U-Boot proper and one device tree blob the SPL can load multiple,
+arbitrary image files as well. These binaries should be specified in their
+own subnode under the /images node, which should then be referenced from one or
+multiple /configurations subnodes. The required images must be enumerated in
+the "loadables" property as a list of strings.
+If a platform specific image source file (.its) is shipped with the U-Boot
+source, it can be specified using the CONFIG_SPL_FIT_SOURCE Kconfig symbol.
+In this case it will be automatically used by U-Boot's Makefile to generate
+the image.
+If a static source file is not flexible enough, CONFIG_SPL_FIT_GENERATOR
+can point to a script which generates this image source file during
+the build process. It gets passed a list of device tree files (taken from the
+CONFIG_OF_LIST symbol).
Example 1 -- old-style (non-FDT) kernel booting
-----------------------------------------------
$ mkimage -l kernel.itb
FIT description: Simple image with single Linux kernel
Created: Tue Mar 11 17:26:15 2008
- Image 0 (kernel@1)
+ Image 0 (kernel)
Description: Vanilla Linux kernel
Type: Kernel Image
Compression: gzip compressed
Hash value: 2ae2bb40
Hash algo: sha1
Hash value: 3c200f34e2c226ddc789240cca0c59fc54a67cf4
- Default Configuration: 'config@1'
- Configuration 0 (config@1)
+ Default Configuration: 'config-1'
+ Configuration 0 (config-1)
Description: Boot Linux kernel
- Kernel: kernel@1
+ Kernel: kernel
The resulting image file kernel.itb can be now transferred to the target,
FIT image found
FIT description: Simple image with single Linux kernel
Created: 2008-03-11 16:26:15 UTC
- Image 0 (kernel@1)
+ Image 0 (kernel)
Description: Vanilla Linux kernel
Type: Kernel Image
Compression: gzip compressed
Hash value: 2ae2bb40
Hash algo: sha1
Hash value: 3c200f34e2c226ddc789240cca0c59fc54a67cf4
- Default Configuration: 'config@1'
- Configuration 0 (config@1)
+ Default Configuration: 'config-1'
+ Configuration 0 (config-1)
Description: Boot Linux kernel
- Kernel: kernel@1
+ Kernel: kernel
=> bootm
## Booting kernel from FIT Image at 00900000 ...
- Using 'config@1' configuration
- Trying 'kernel@1' kernel subimage
+ Using 'config-1' configuration
+ Trying 'kernel' kernel subimage
Description: Vanilla Linux kernel
Type: Kernel Image
Compression: gzip compressed
$ mkimage -l kernel_fdt.itb
FIT description: Simple image with single Linux kernel and FDT blob
Created: Tue Mar 11 16:29:22 2008
- Image 0 (kernel@1)
+ Image 0 (kernel)
Description: Vanilla Linux kernel
Type: Kernel Image
Compression: gzip compressed
Hash value: 2c0cc807
Hash algo: sha1
Hash value: 264b59935470e42c418744f83935d44cdf59a3bb
- Image 1 (fdt@1)
+ Image 1 (fdt-1)
Description: Flattened Device Tree blob
Type: Flat Device Tree
Compression: uncompressed
Hash value: 0d655d71
Hash algo: sha1
Hash value: 25ab4e15cd4b8a5144610394560d9c318ce52def
- Default Configuration: 'conf@1'
- Configuration 0 (conf@1)
+ Default Configuration: 'conf-1'
+ Configuration 0 (conf-1)
Description: Boot Linux kernel with FDT blob
- Kernel: kernel@1
- FDT: fdt@1
+ Kernel: kernel
+ FDT: fdt-1
The resulting image file kernel_fdt.itb can be now transferred to the target,
FIT image found
FIT description: Simple image with single Linux kernel and FDT blob
Created: 2008-03-11 15:29:22 UTC
- Image 0 (kernel@1)
+ Image 0 (kernel)
Description: Vanilla Linux kernel
Type: Kernel Image
Compression: gzip compressed
Hash value: 2c0cc807
Hash algo: sha1
Hash value: 264b59935470e42c418744f83935d44cdf59a3bb
- Image 1 (fdt@1)
+ Image 1 (fdt-1)
Description: Flattened Device Tree blob
Type: Flat Device Tree
Compression: uncompressed
Hash value: 0d655d71
Hash algo: sha1
Hash value: 25ab4e15cd4b8a5144610394560d9c318ce52def
- Default Configuration: 'conf@1'
- Configuration 0 (conf@1)
+ Default Configuration: 'conf-1'
+ Configuration 0 (conf-1)
Description: Boot Linux kernel with FDT blob
- Kernel: kernel@1
- FDT: fdt@1
+ Kernel: kernel
+ FDT: fdt-1
=> bootm
## Booting kernel from FIT Image at 00900000 ...
- Using 'conf@1' configuration
- Trying 'kernel@1' kernel subimage
+ Using 'conf-1' configuration
+ Trying 'kernel' kernel subimage
Description: Vanilla Linux kernel
Type: Kernel Image
Compression: gzip compressed
Verifying Hash Integrity ... crc32+ sha1+ OK
Uncompressing Kernel Image ... OK
## Flattened Device Tree from FIT Image at 00900000
- Using 'conf@1' configuration
- Trying 'fdt@1' FDT blob subimage
+ Using 'conf-1' configuration
+ Trying 'fdt-1' FDT blob subimage
Description: Flattened Device Tree blob
Type: Flat Device Tree
Compression: uncompressed
projects / oweals / u-boot.git / blobdiff