On Fri, Jan 26, 2024 at 1:04 AM Simon Glass sjg@chromium.org wrote:
Hi,
On Wed, 17 Jan 2024 at 06:14, Simon Glass sjg@chromium.org wrote:
Hi Masahiro, Tom,
On Tue, 9 Jan 2024 at 07:33, Tom Rini trini@konsulko.com wrote:
On Tue, Jan 09, 2024 at 11:01:42PM +0900, Masahiro Yamada wrote:
Hi Simon,
On Wed, Jan 3, 2024 at 8:47 AM Simon Glass sjg@chromium.org wrote:
Hi Masahiro,
On Wed, Dec 13, 2023 at 5:14 AM Will Deacon will@kernel.org wrote:
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 > $(obj)/image.fit > > While FIT supports a ramdisk / initrd, no attempt is made to support > this here, since it must be built separately from the Linux build. > > Signed-off-by: Simon Glass sjg@chromium.org > --- > > Changes in v9: > - Move the compression control into Makefile.lib > > Changes in v8: > - Drop compatible string in FDT node > - Correct sorting of MAINTAINERS to before ARM64 PORT > - Turn compress part of the make_fit.py comment in to a sentence > - Add two blank lines before parse_args() and setup_fit() > - Use 'image.fit: dtbs' instead of BUILD_DTBS var > - Use '$(<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.
Any thoughts on this request, please?
Regards, Simon
As I mentioned before, I am concerned with having the same "compatible" entries, with different contents, as you use the "compatible" string as an ID to selecting the target config node, right?
$ fdtdump arch/arm64/boot/image.fit
... conf-10 { compatible = "tq,am642-tqma6442l-mbax4xxl","tq,am642-tqma6442l", "ti,am642"; description = "TQ-Systems TQMa64xxL SoM on MBax4xxL carrier board"; fdt = "fdt-10"; kernel = "kernel"; };
... conf-25 { compatible = "tq,am642-tqma6442l-mbax4xxl","tq,am642-tqma6442l", "ti,am642"; description = "TQ-Systems TQMa64xxL SoM on MBax4xxL carrier board"; fdt = "fdt-25"; kernel = "kernel"; };
I had asked Rob a while ago about if having the same compatible for two functionally different machines is a feature, or a bug, and I don't think either of us fully agreed either way. I'd be leaning towards saying the above example is a bug in the dts files, it's just not been a bug people have worried about before due to (sadly) how little the top-level compatible has been used.
Yes I believe this is a bug in the files.
What should the script do in this case? Print a warning, perhaps?
Is there anything I should do here? Would a warning be helpful, or just confusing?
I do not think it is useful. You would almost always get a warning, and there is no way to fix it.
With arm64 defconfig, image.fit will include a thousand DTBs.
The config node of my board was listed 214th. (I found it by fdtdump)
Then, I learned
bootm ${loadaddr}#conf-214
is the correct command to boot my board.
Of course, the "214" will be different in the future.
The node names, conf-*, are useless.
Only the useful way is to enable CONFIG_FIT_BEST_MATCH in U-Boot, but this relies on the uniqueness of a compatible string, which is not true.
(I do not know how to do it in barebox)
I think using the file name as a config node mitigates the issue because a file name is considered unique.
For example, with composite DTBs:
imx8mm-venice-gw72xx-0x-imx219-dtbs := imx8mm-venice-gw72xx-0x.dtb imx8mm-venice-gw72xx-0x-imx219.dtbo imx8mm-venice-gw72xx-0x-rpidsi-dtbs := imx8mm-venice-gw72xx-0x.dtb imx8mm-venice-gw72xx-0x-rpidsi.dtbo
configurations { imx8mm-venice-gw72xx-0x-imx219 { ... };
imx8mm-venice-gw72xx-0x-rpidsi { ... } };
Then, we can distinguish them by node, even if they have the same compatible string. At least we can do
bootm ${loadaddr}#imx8mm-venice-gw72xx-0x-imx219
For the issue including stale DTBs, you can use my patch: [PATCH 1/4] kbuild: create a list of all built DTB files (https://lore.kernel.org/linux-kbuild/CAK7LNASOxi-gzve+_d-sCW9z_eEJ5TMMnzPEvN...)
You can change scripts/make_fit.py to take the DTB files instead of the directory to search.
Optionally, you can support '@' syntax to take command arguments from a file.
scripts/make_fit.py ... @arch/$(SRCARCH)/boot/dts/dtbs-list
For the separate base and overlays support, you can use my patch as a base: [PATCH 3/4] kbuild: create a list of base and overlays for each DTB (https://lore.kernel.org/linux-kbuild/CAK7LNASOxi-gzve+_d-sCW9z_eEJ5TMMnzPEvN...)
Lastly, you do not need to require mkimage for args.external. You can simply concatenate files.
-- Best Regards Masahiro Yamada