Hi Masahiro,

On Wed, 27 Mar 2024 at 03:39, Masahiro Yamada [off-list ref] wrote:

On Thu, Mar 14, 2024 at 1:28 PM Simon Glass [off-list ref] wrote:

quoted

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.

The FIT can be examined using 'dumpimage -l'.

This uses the 'dtbs-list' file but processes only .dtb files, ignoring
the overlay .dtbo files.

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. Use
FIT_COMPRESSION to select an algorithm other than gzip.

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@chromium.org>
---

Changes in v11:
- Use dtbslist file in image.fit rule
- Update cmd_fit rule as per Masahiro
- Don't mention ignoring files without a .dtb prefix
- Use argparse fromfile_prefix_chars feature
- Add a -v option and use it for output (with make V=1)
- rename srcdir to dtbs
- Use -o for the output file instead of -f

quoted

--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib

@@ -504,6 +504,21 @@ quiet_cmd_uimage = UIMAGE  $@
                        -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
                        -n '$(UIMAGE_NAME)' -d $< $@

+# Flat Image Tree (FIT)
+# This allows for packaging of a kernel and all devicetrees files, using
+# compression.
+# ---------------------------------------------------------------------------
+
+MAKE_FIT := $(srctree)/scripts/make_fit.py
+
+# Use this to override the compression algorithm
+FIT_COMPRESSION ?= gzip
+
+quiet_cmd_fit = FIT     $@
+      cmd_fit = $(MAKE_FIT) -o $@ --arch $(UIMAGE_ARCH) --os linux \
+               --name '$(UIMAGE_NAME)' $(if $(V),-v) \
+               --compress $(FIT_COMPRESSION) -k $< @$(word 2,$^)
+

A nit in your new code.


$(if $(V),-v) does not work for KBUILD_VERBOSE env variable.


It should be

    $(if $(findstring 1,$(KBUILD_VERBOSE)),-v)

OK, thank you. I was assuming that V=0 would not be passed, but this
is better. I will send v12.

Regards,
Simon

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