[RFC PATCH 0/7] arm64: Add fit images for sc7180-trogdor and google,lga

[Douglas Anderson <dianders@chromium.org>]

The end goal of this series is to move forward on producing a
"universal" Pixel 10 boot image that can boot on a variety of Pixel
10 devices (frankel, blazer, and mustang and eventually multiple
revisions of each). At the moment, this is impossible since the Pixel
10 bootloader:
* Picks the base devicetree based on SoC ID information.
* Picks an overlay devicetree based on Board ID information.
* Needs metadata associated with each overlay to match it up.

Since we don't have per-board overlays and don't have per-board
metadata, that means that today you need to pick exactly one revision
of one board and build a boot image just for that.

How does this series help us?
1. It uses a checked-in .its script to associate metadata with each
   board's devicetree. Other tools can parse this metadata in order to
   craft a package that the Pixel bootloader can understand.
2. It integrates a call to the new `fdtfactor` tool [1], which results
   in a "base dtb + board dtbo" that looks like what the bootloader
   needs, at least as long as all the boards have the same SoC.

What happens if everyone hates this series and it gets dropped on the
floor? Honestly, everything here could just go out of tree and it
would be "fine". IMO it's nice to have the Board ID / SoC ID
information for each devicetree stored in the same repository as the
devicetrees themselves are, but if this has to live somewhere else
then so be it.

NOTE: from reading the above, you might wonder why the sc7180-trogdor
.its script is part of this series. The answer: it's a board I was
previously deeply involved in and it is a convenient way for me to
prove out that the Chromebook use case works well. I did hack up some
changes to the ChromeOS build system to use the provided FIT image and
it worked great, but since I'm not on the ChromeOS team these days
it's not something I personally plan to follow-up with. It sounds
plausible that Chen-Yu may follow-up with it or post a similar change
for some Mediatek Chromebooks.

[1] http://lore.kernel.org/r/20261015182221.2931742-1-dianders@chromium.org


Douglas Anderson (7):
  scripts/dtc: Add fdtget.c and fdtput.c to sync script
  scripts/dtc: Update to upstream version v1.8.1-22-gf3451d12532b
  scripts/dtc: Build fdtget and fdtput host tools
  arm64: boot: Support building image.fit from a specified FIT_ITS
    script
  kbuild: fit: Add opt-in FIT_FACTOR_DTBS support using fdtfactor
  arm64: dts: google: lga: Add lga.its FIT image script
  arm64: dts: qcom: sc7180: Add sc7180-trogdor.its FIT image script

 Makefile                                    |   2 +-
 arch/arm64/Makefile                         |   3 +
 arch/arm64/boot/Makefile                    |   9 +-
 arch/arm64/boot/dts/google/lga.its          |  68 ++
 arch/arm64/boot/dts/qcom/sc7180-trogdor.its | 728 ++++++++++++++++++++
 scripts/Makefile.dtbs                       |  51 +-
 scripts/Makefile.lib                        |  67 +-
 scripts/dtc/.gitignore                      |   2 +
 scripts/dtc/Makefile                        |   6 +-
 scripts/dtc/checks.c                        |   2 +-
 scripts/dtc/fdtget.c                        | 207 +++---
 scripts/dtc/fdtput.c                        | 280 ++++++--
 scripts/dtc/libfdt/fdt_ro.c                 |   2 +
 scripts/dtc/libfdt/fdt_rw.c                 |  41 +-
 scripts/dtc/libfdt/fdt_sw.c                 |   3 +-
 scripts/dtc/libfdt/libfdt.h                 |  70 +-
 scripts/dtc/livetree.c                      |   2 +-
 scripts/dtc/update-dtc-source.sh            |   4 +-
 scripts/dtc/version_gen.h                   |   2 +-
 19 files changed, 1322 insertions(+), 227 deletions(-)
 create mode 100644 arch/arm64/boot/dts/google/lga.its
 create mode 100644 arch/arm64/boot/dts/qcom/sc7180-trogdor.its

-- 
2.56.0.212.g129ede20d9-goog