On Fri, Dec 01, 2023 at 08:54:42PM -0700, Simon Glass wrote: > Add a script which produces a Flat Image Tree (FIT), a single file > containing the built kernel and associated devicetree files. > Compression defaults to gzip which gives a good balance of size and > performance. > > The files compress from about 86MB to 24MB using this approach. > > The FIT can be used by bootloaders which support it, such as U-Boot > and Linuxboot. It permits automatic selection of the correct > devicetree, matching the compatible string of the running board with > the closest compatible string in the FIT. There is no need for > filenames or other workarounds. > > Add a 'make image.fit' build target for arm64, as well. Use > FIT_COMPRESSION to select a different algorithm. > > The FIT can be examined using 'dumpimage -l'. > > This features requires pylibfdt (use 'pip install libfdt'). It also > requires compression utilities for the algorithm being used. Supported > compression options are the same as the Image.xxx files. For now there > is no way to change the compression other than by editing the rule for > $(obj)/image.fit > > While FIT supports a ramdisk / initrd, no attempt is made to support > this here, since it must be built separately from the Linux build. > > Signed-off-by: Simon Glass <sjg@xxxxxxxxxxxx> > --- > > Changes in v9: > - Move the compression control into Makefile.lib > > Changes in v8: > - Drop compatible string in FDT node > - Correct sorting of MAINTAINERS to before ARM64 PORT > - Turn compress part of the make_fit.py comment in to a sentence > - Add two blank lines before parse_args() and setup_fit() > - Use 'image.fit: dtbs' instead of BUILD_DTBS var > - Use '$(<D)/dts' instead of '$(dir $<)dts' > - Add 'mkimage' details Documentation/process/changes.rst > - Allow changing the compression used > - Tweak cover letter since there is only one clean-up patch > > Changes in v7: > - Add Image as a dependency of image.fit > - Drop kbuild tag > - Add dependency on dtbs > - Drop unnecessary path separator for dtbs > - Rebase to -next > > Changes in v5: > - Drop patch previously applied > - Correct compression rule which was broken in v4 > > Changes in v4: > - Use single quotes for UIMAGE_NAME > > Changes in v3: > - Drop temporary file image.itk > - Drop patch 'Use double quotes for image name' > - Drop double quotes in use of UIMAGE_NAME > - Drop unnecessary CONFIG_EFI_ZBOOT condition for help > - Avoid hard-coding "arm64" for the DT architecture > > Changes in v2: > - Drop patch previously applied > - Add .gitignore file > - Move fit rule to Makefile.lib using an intermediate file > - Drop dependency on CONFIG_EFI_ZBOOT > - Pick up .dtb files separately from the kernel > - Correct pylint too-many-args warning for write_kernel() > - Include the kernel image in the file count > - Add a pointer to the FIT spec and mention of its wide industry usage > - Mention the kernel version in the FIT description > > Documentation/process/changes.rst | 9 + > MAINTAINERS | 7 + > arch/arm64/Makefile | 7 +- > arch/arm64/boot/.gitignore | 1 + > arch/arm64/boot/Makefile | 6 +- > scripts/Makefile.lib | 16 ++ > scripts/make_fit.py | 291 ++++++++++++++++++++++++++++++ > 7 files changed, 334 insertions(+), 3 deletions(-) > create mode 100755 scripts/make_fit.py I'll need Masahiro's Ack on the scripts/ changes before I can take this one. Will
